Commit Graph

3866 Commits

Author SHA1 Message Date
Ravi Bangoria 18d45b11d9 trace_uprobe: Use %lx to display offset
tu->offset is unsigned long, not a pointer, thus %lx should
be used to print it, not the %px.

Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 0e4d819d08 ("trace_uprobe: Display correct offset in uprobe_events")
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:31:07 -04:00
Howard McLauchlan f0a2aa5a2a tracing/uprobe: Add support for overlayfs
uprobes cannot successfully attach to binaries located in a directory
mounted with overlayfs.

To verify, create directories for mounting overlayfs
(upper,lower,work,merge), move some binary into merge/ and use readelf
to obtain some known instruction of the binary. I used /bin/true and the
entry instruction(0x13b0):

	$ mount -t overlay overlay -o lowerdir=lower,upperdir=upper,workdir=work merge
	$ cd /sys/kernel/debug/tracing
	$ echo 'p:true_entry PATH_TO_MERGE/merge/true:0x13b0' > uprobe_events
	$ echo 1 > events/uprobes/true_entry/enable

This returns 'bash: echo: write error: Input/output error' and dmesg
tells us 'event trace: Could not enable event true_entry'

This change makes create_trace_uprobe() look for the real inode of a
dentry. In the case of normal filesystems, this simplifies to just
returning the inode. In the case of overlayfs(and similar fs) we will
obtain the underlying dentry and corresponding inode, upon which uprobes
can successfully register.

Running the example above with the patch applied, we can see that the
uprobe is enabled and will output to trace as expected.

Link: http://lkml.kernel.org/r/20180410231030.2720-1-hmclauchlan@fb.com

Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:31:06 -04:00
Jérémy Lefaure 0a4d0564f0 tracing: Use ARRAY_SIZE() macro instead of open coding it
It is useless to re-invent the ARRAY_SIZE macro so let's use it instead
of DATA_CNT.

Found with Coccinelle with the following semantic patch:
@r depends on (org || report)@
type T;
T[] E;
position p;
@@
(
 (sizeof(E)@p /sizeof(*E))
|
 (sizeof(E)@p /sizeof(E[...]))
|
 (sizeof(E)@p /sizeof(T))
)

Link: http://lkml.kernel.org/r/20171016012250.26453-1-jeremy.lefaure@lse.epita.fr

Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
[ Removed useless include of kernel.h ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11 11:30:33 -04:00
Yonghong Song 3a38bb98d9 bpf/tracing: fix a deadlock in perf_event_detach_bpf_prog
syzbot reported a possible deadlock in perf_event_detach_bpf_prog.
The error details:
  ======================================================
  WARNING: possible circular locking dependency detected
  4.16.0-rc7+ #3 Not tainted
  ------------------------------------------------------
  syz-executor7/24531 is trying to acquire lock:
   (bpf_event_mutex){+.+.}, at: [<000000008a849b07>] perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854

  but task is already holding lock:
   (&mm->mmap_sem){++++}, at: [<0000000038768f87>] vm_mmap_pgoff+0x198/0x280 mm/util.c:353

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #1 (&mm->mmap_sem){++++}:
       __might_fault+0x13a/0x1d0 mm/memory.c:4571
       _copy_to_user+0x2c/0xc0 lib/usercopy.c:25
       copy_to_user include/linux/uaccess.h:155 [inline]
       bpf_prog_array_copy_info+0xf2/0x1c0 kernel/bpf/core.c:1694
       perf_event_query_prog_array+0x1c7/0x2c0 kernel/trace/bpf_trace.c:891
       _perf_ioctl kernel/events/core.c:4750 [inline]
       perf_ioctl+0x3e1/0x1480 kernel/events/core.c:4770
       vfs_ioctl fs/ioctl.c:46 [inline]
       do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

  -> #0 (bpf_event_mutex){+.+.}:
       lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
       __mutex_lock_common kernel/locking/mutex.c:756 [inline]
       __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
       perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854
       perf_event_free_bpf_prog kernel/events/core.c:8147 [inline]
       _free_event+0xbdb/0x10f0 kernel/events/core.c:4116
       put_event+0x24/0x30 kernel/events/core.c:4204
       perf_mmap_close+0x60d/0x1010 kernel/events/core.c:5172
       remove_vma+0xb4/0x1b0 mm/mmap.c:172
       remove_vma_list mm/mmap.c:2490 [inline]
       do_munmap+0x82a/0xdf0 mm/mmap.c:2731
       mmap_region+0x59e/0x15a0 mm/mmap.c:1646
       do_mmap+0x6c0/0xe00 mm/mmap.c:1483
       do_mmap_pgoff include/linux/mm.h:2223 [inline]
       vm_mmap_pgoff+0x1de/0x280 mm/util.c:355
       SYSC_mmap_pgoff mm/mmap.c:1533 [inline]
       SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1491
       SYSC_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
       SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:91
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

  other info that might help us debug this:

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(&mm->mmap_sem);
                                 lock(bpf_event_mutex);
                                 lock(&mm->mmap_sem);
    lock(bpf_event_mutex);

   *** DEADLOCK ***
  ======================================================

The bug is introduced by Commit f371b304f1 ("bpf/tracing: allow
user space to query prog array on the same tp") where copy_to_user,
which requires mm->mmap_sem, is called inside bpf_event_mutex lock.
At the same time, during perf_event file descriptor close,
mm->mmap_sem is held first and then subsequent
perf_event_detach_bpf_prog needs bpf_event_mutex lock.
Such a senario caused a deadlock.

As suggested by Daniel, moving copy_to_user out of the
bpf_event_mutex lock should fix the problem.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: syzbot+dc5ca0e4c9bfafaf2bae@syzkaller.appspotmail.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-11 01:01:40 +02:00
Linus Torvalds 2a56bb596b New features:
- Tom Zanussi's extended histogram work
    This adds the synthetic events to have histograms from multiple event data
    Adds triggers "onmatch" and "onmax" to call the synthetic events
    Several updates to the histogram code from this
 
  - Allow way to nest ring buffer calls in the same context
 
  - Allow absolute time stamps in ring buffer
 
  - Rewrite of filter code parsing based on Al Viro's suggestions
 
  - Setting of trace_clock to global if TSC is unstable (on boot)
 
  - Better OOM handling when allocating large ring buffers
 
  - Added initcall tracepoints (consolidated initcall_debug code with them)
 
 And other various fixes and clean ups
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlrLoCAUHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUks/QwAn/ky8WgfjcRdjKmBYuEwDedvm9iI
 V9G5kpv5JMw5dLz4l1pS3tA3M9Lyuc5z3Shw92FTy36vdU1wxEjQgHa7viB1xk9x
 KsiTyNjTsgrRd7GVHMy/8Be2RRiTRLaXKAsLCoj/c7QWzagV1P8XWlWK5mojYkh/
 DrSXyg9Avkp30+sU1bvcLWnmmZUFqMxs+bWipD9uFc98USMMyeP25nrnhrj0gDTg
 Q93cjXUuyVRC4lJ2YTW0GCSKhMKEw5f/ltEOT1hwScqYkCJj1EubKqS53R/9h21z
 IPUrYcqLnMRu0j2ejR+UAy5Vsy3gJUrPMQb0F6hlu1DwbMd0d/9SGh1c+Sm+zorh
 yftWTdCZsYrXkaOuB6V5M30X+KBwbWO0Xc9VCvgJ/IU5vMlgLSt5itTWbT/Fmfhb
 ll5/RXP7zhSXRv5sdl/BP3/4dd6F8jpyKyaR2Rk2+XjBOGIq5mvqNGr4Vj9AzxW8
 E0nvq7l7e0dbxZNM42gEm3cht1VUg7Zz0Y0+
 =91oN
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "New features:

   - Tom Zanussi's extended histogram work.

     This adds the synthetic events to have histograms from multiple
     event data Adds triggers "onmatch" and "onmax" to call the
     synthetic events Several updates to the histogram code from this

   - Allow way to nest ring buffer calls in the same context

   - Allow absolute time stamps in ring buffer

   - Rewrite of filter code parsing based on Al Viro's suggestions

   - Setting of trace_clock to global if TSC is unstable (on boot)

   - Better OOM handling when allocating large ring buffers

   - Added initcall tracepoints (consolidated initcall_debug code with
     them)

  And other various fixes and clean ups"

* tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (68 commits)
  init: Have initcall_debug still work without CONFIG_TRACEPOINTS
  init, tracing: Have printk come through the trace events for initcall_debug
  init, tracing: instrument security and console initcall trace events
  init, tracing: Add initcall trace events
  tracing: Add rcu dereference annotation for test func that touches filter->prog
  tracing: Add rcu dereference annotation for filter->prog
  tracing: Fixup logic inversion on setting trace_global_clock defaults
  tracing: Hide global trace clock from lockdep
  ring-buffer: Add set/clear_current_oom_origin() during allocations
  ring-buffer: Check if memory is available before allocation
  lockdep: Add print_irqtrace_events() to __warn
  vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK)
  tracing: Uninitialized variable in create_tracing_map_fields()
  tracing: Make sure variable string fields are NULL-terminated
  tracing: Add action comparisons when testing matching hist triggers
  tracing: Don't add flag strings when displaying variable references
  tracing: Fix display of hist trigger expressions containing timestamps
  ftrace: Drop a VLA in module_exists()
  tracing: Mention trace_clock=global when warning about unstable clocks
  tracing: Default to using trace_global_clock if sched_clock is unstable
  ...
2018-04-10 11:27:30 -07:00
Masami Hiramatsu 50268a3d26 tracing/uprobe_event: Fix strncpy corner case
Fix string fetch function to terminate with NUL.
It is OK to drop the rest of string.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org
Cc: 范龙飞 <long7573@126.com>
Fixes: 5baaa59ef0 ("tracing/probes: Implement 'memory' fetch method for uprobes")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-10 20:14:11 +02:00
Song Liu 0eadcc7a7b perf/core: Fix perf_uprobe_init()
Similarly to the uprobe PMU fix in perf_kprobe_init(), fix error
handling in perf_uprobe_init() as well.

Reported-by: 范龙飞 <long7573@126.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-10 07:33:10 +02:00
Masami Hiramatsu 5da13ab8b0 perf/core: Fix perf_kprobe_init()
Fix error handling in perf_kprobe_init():

	==================================================================
	BUG: KASAN: slab-out-of-bounds in strlen+0x8e/0xa0 lib/string.c:482
	Read of size 1 at addr ffff88003f9cc5c0 by task syz-executor2/23095

	CPU: 0 PID: 23095 Comm: syz-executor2 Not tainted 4.16.0+ #24
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
	Call Trace:
	 __dump_stack lib/dump_stack.c:77 [inline]
	 dump_stack+0xca/0x13e lib/dump_stack.c:113
	 print_address_description+0x6e/0x2c0 mm/kasan/report.c:256
	 kasan_report_error mm/kasan/report.c:354 [inline]
	 kasan_report+0x256/0x380 mm/kasan/report.c:412
	 strlen+0x8e/0xa0 lib/string.c:482
	 kstrdup+0x21/0x70 mm/util.c:55
	 alloc_trace_kprobe+0xc8/0x930 kernel/trace/trace_kprobe.c:325
	 create_local_trace_kprobe+0x4f/0x3a0 kernel/trace/trace_kprobe.c:1438
	 perf_kprobe_init+0x149/0x1f0 kernel/trace/trace_event_perf.c:264
	 perf_kprobe_event_init+0xa8/0x120 kernel/events/core.c:8407
	 perf_try_init_event+0xcb/0x2a0 kernel/events/core.c:9719
	 perf_init_event kernel/events/core.c:9750 [inline]
	 perf_event_alloc+0x1367/0x1e20 kernel/events/core.c:10022
	 SYSC_perf_event_open+0x242/0x2330 kernel/events/core.c:10477
	 do_syscall_64+0x198/0x640 arch/x86/entry/common.c:287
	 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Reported-by: 范龙飞 <long7573@126.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-10 07:33:10 +02:00
Steven Rostedt (VMware) 8ec8405f08 tracing: Add rcu dereference annotation for test func that touches filter->prog
A boot up test function update_pred_fn() dereferences filter->prog without
the proper rcu annotation.

To do this, we must also take the event_mutex first. Normally, this isn't
needed because this test function can not race with other use cases that
touch the event filters (it is disabled if any events are enabled).

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:54 -04:00
Steven Rostedt (VMware) 1f3b0faa3e tracing: Add rcu dereference annotation for filter->prog
ftrace_function_set_filter() referenences filter->prog without annotation
and sparse complains about it. It needs a rcu_dereference_protected()
wrapper.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:53 -04:00
Chris Wilson 5125eee4e6 tracing: Fixup logic inversion on setting trace_global_clock defaults
In commit 932066a15335 ("tracing: Default to using trace_global_clock if
sched_clock is unstable"), the logic for deciding to override the
default clock if unstable was reversed from the earlier posting. I was
trying to reduce the width of the message by using an early return
rather than a if-block, but reverted back to using the if-block and
accidentally left the predicate inverted.

Link: http://lkml.kernel.org/r/20180404212450.26646-1-chris@chris-wilson.co.uk

Fixes: 932066a15335 ("tracing: Default to using trace_global_clock if sched_clock is unstable")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:53 -04:00
Steven Rostedt (VMware) f7a1570da9 tracing: Hide global trace clock from lockdep
Function tracing can trace in NMIs and such. If the TSC is determined
to be unstable, the tracing clock will switch to the global clock on
boot up, unless "trace_clock" is specified on the kernel command line.

The global clock disables interrupts to access sched_clock_cpu(), and in
doing so can be done within lockdep internals (because of function
tracing and NMIs). This can trigger false lockdep splats.

The trace_clock_global() is special, best not to trace the irq logic
within it.

Link: http://lkml.kernel.org/r/20180404145015.77bde42d@gandalf.local.home

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:52 -04:00
Steven Rostedt (VMware) 927e56db62 ring-buffer: Add set/clear_current_oom_origin() during allocations
As si_mem_available() can say there is enough memory even though the memory
available is not useable by the ring buffer, it is best to not kill innocent
applications because the ring buffer is taking up all the memory while it is
trying to allocate a great deal of memory.

If the allocator is user space (because kernel threads can also increase the
size of the kernel ring buffer on boot up), then after si_mem_available()
says there is enough memory, set the OOM killer to kill the current task if
an OOM triggers during the allocation.

Link: http://lkml.kernel.org/r/20180404062340.GD6312@dhcp22.suse.cz

Suggested-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:52 -04:00
Steven Rostedt (VMware) 2a872fa4e9 ring-buffer: Check if memory is available before allocation
The ring buffer is made up of a link list of pages. When making the ring
buffer bigger, it will allocate all the pages it needs before adding to the
ring buffer, and if it fails, it frees them and returns an error. This makes
increasing the ring buffer size an all or nothing action. When this was
first created, the pages were allocated with "NORETRY". This was to not
cause any Out-Of-Memory (OOM) actions from allocating the ring buffer. But
NORETRY was too strict, as the ring buffer would fail to expand even when
there's memory available, but was taken up in the page cache.

Commit 848618857d ("tracing/ring_buffer: Try harder to allocate") changed
the allocating from NORETRY to RETRY_MAYFAIL. The RETRY_MAYFAIL would
allocate from the page cache, but if there was no memory available, it would
simple fail the allocation and not trigger an OOM.

This worked fine, but had one problem. As the ring buffer would allocate one
page at a time, it could take up all memory in the system before it failed
to allocate and free that memory. If the allocation is happening and the
ring buffer allocates all memory and then tries to take more than available,
its allocation will not trigger an OOM, but if there's any allocation that
happens someplace else, that could trigger an OOM, even though once the ring
buffer's allocation fails, it would free up all the previous memory it tried
to allocate, and allow other memory allocations to succeed.

Commit d02bd27bd3 ("mm/page_alloc.c: calculate 'available' memory in a
separate function") separated out si_mem_availble() as a separate function
that could be used to see how much memory is available in the system. Using
this function to make sure that the ring buffer could be allocated before it
tries to allocate pages we can avoid allocating all memory in the system and
making it vulnerable to OOMs if other allocations are taking place.

Link: http://lkml.kernel.org/r/1522320104-6573-1-git-send-email-zhaoyang.huang@spreadtrum.com

CC: stable@vger.kernel.org
Cc: linux-mm@kvack.org
Fixes: 848618857d ("tracing/ring_buffer: Try harder to allocate")
Requires: d02bd27bd3 ("mm/page_alloc.c: calculate 'available' memory in a separate function")
Reported-by: Zhaoyang Huang <huangzhaoyang@gmail.com>
Tested-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:52 -04:00
Dan Carpenter b28d7b2dc2 tracing: Uninitialized variable in create_tracing_map_fields()
Smatch complains that idx can be used uninitialized when we check if
(idx < 0).  It has to be the first iteration through the loop and the
HIST_FIELD_FL_STACKTRACE bit has to be clear and the HIST_FIELD_FL_VAR
bit has to be set to reach the bug.

Link: http://lkml.kernel.org/r/20180328114815.GC29050@mwanda

Fixes: 30350d65ac ("tracing: Add variable support to hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:50 -04:00
Tom Zanussi ad452870c6 tracing: Make sure variable string fields are NULL-terminated
The strncpy() currently being used for variable string fields can
result in a lack of termination if the string length is equal to the
field size.  Use the safer strscpy() instead, which will guarantee
termination.

Link: http://lkml.kernel.org/r/fb97c1e518fb358c12a4057d7445ba2c46956cd7.1522256721.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:50 -04:00
Tom Zanussi 48f794731e tracing: Add action comparisons when testing matching hist triggers
Actions also need to be considered when checking for matching triggers
- triggers differing only by action should be allowed, but currently
aren't because the matching check ignores the action and erroneously
returns -EEXIST.

Add and call an actions_match() function to address that.

Here's an example using onmatch() actions.  The first -EEXIST shouldn't
occur because the onmatch() is different in the second wakeup_latency()
param.  The second -EEXIST shouldn't occur because it's a different
action (in this case, it doesn't have an action, so shouldn't be seen
as being the same and therefore rejected).

In the after case, both are correctly accepted (and trying to add one of
them again returns -EEXIST as it should).

before:

  # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events
  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: File exists
  # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: File exists

after:

  # echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events
  # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  # echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

Link: http://lkml.kernel.org/r/a7fd668b87ec10736c8f016ac4279c8480d50c2b.1522256721.git.tom.zanussi@linux.intel.com

Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:49 -04:00
Tom Zanussi 76690945f5 tracing: Don't add flag strings when displaying variable references
Variable references should never have flags appended when displayed -
prevent that from happening.

Before:

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:...

After:

  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0:...

Link: http://lkml.kernel.org/r/913318a5610ef6b24af2522575f671fa6ee19b6b.1522256721.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:49 -04:00
Tom Zanussi 0ae7961e75 tracing: Fix display of hist trigger expressions containing timestamps
When displaying hist triggers, variable references that have the
timestamp field flag set are erroneously displayed as common_timestamp
rather than the variable reference.  Additionally, timestamp
expressions are displayed in the same way.  Fix this by forcing the
timestamp flag handling to follow variable reference and expression
handling.

Before:

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs:...

After:

  # cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
  hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:...

Link: http://lkml.kernel.org/r/92746b06be67499c2a6217bd55395b350ad18fad.1522256721.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:48 -04:00
Salvatore Mesoraca 419e9fe53b ftrace: Drop a VLA in module_exists()
Avoid a VLA by using a real constant expression instead of a variable.
The compiler should be able to optimize the original code and avoid using
an actual VLA. Anyway this change is useful because it will avoid a false
positive with -Wvla, it might also help the compiler generating better
code.

Link: http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Link: http://lkml.kernel.org/r/1522399988-8815-1-git-send-email-s.mesoraca16@gmail.com

Signed-off-by: Salvatore Mesoraca <s.mesoraca16@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:48 -04:00
Chris Wilson 913ea4d0b1 tracing: Mention trace_clock=global when warning about unstable clocks
Mention the alternative of adding trace_clock=global to the kernel
command line when we detect that we've used an unstable clock across a
suspend/resume cycle.

Link: http://lkml.kernel.org/r/20180330150132.16903-2-chris@chris-wilson.co.uk

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:47 -04:00
Chris Wilson 3fd49c9e48 tracing: Default to using trace_global_clock if sched_clock is unstable
Across suspend, we may see a very large drift in timestamps if the sched
clock is unstable, prompting the global trace's ringbuffer code to warn
and suggest switching to the global clock. Preempt this request by
detecting when the sched clock is unstable (determined during
late_initcall) and automatically switching the default clock over to
trace_global_clock.

This should prevent requiring user interaction to resolve warnings such
as:

    Delta way too big! 18446743856563626466 ts=18446744054496180323 write stamp = 197932553857
    If you just came from a suspend/resume,
    please switch to the trace global clock:
    echo global > /sys/kernel/debug/tracing/trace_clock

Link: http://lkml.kernel.org/r/20180330150132.16903-1-chris@chris-wilson.co.uk

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-06 08:56:47 -04:00
Linus Torvalds 672a9c1069 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  kfifo: fix inaccurate comment
  tools/thermal: tmon: fix for segfault
  net: Spelling s/stucture/structure/
  edd: don't spam log if no EDD information is present
  Documentation: Fix early-microcode.txt references after file rename
  tracing: Block comments should align the * on each line
  treewide: Fix typos in printk
  GenWQE: Fix a typo in two comments
  treewide: Align function definition open/close braces
2018-04-05 11:56:35 -07:00
Linus Torvalds 680014d6d1 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull time(r) updates from Thomas Gleixner:
 "A small set of updates for timers and timekeeping:

   - The most interesting change is the consolidation of clock MONOTONIC
     and clock BOOTTIME.

     Clock MONOTONIC behaves now exactly like clock BOOTTIME and does
     not longer ignore the time spent in suspend. A new clock
     MONOTONIC_ACTIVE is provived which behaves like clock MONOTONIC in
     kernels before this change. This allows applications to
     programmatically check for the clock MONOTONIC behaviour.

     As discussed in the review thread, this has the potential of
     breaking user space and we might have to revert this. Knock on wood
     that we can avoid that exercise.

   - Updates to the NTP mechanism to improve accuracy

   - A new kernel internal data structure to aid the ongoing Y2038 work.

   - Cleanups and simplifications of the clocksource code.

   - Make the alarmtimer code play nicely with debugobjects"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  alarmtimer: Init nanosleep alarm timer on stack
  y2038: Introduce struct __kernel_old_timeval
  tracing: Unify the "boot" and "mono" tracing clocks
  hrtimer: Unify MONOTONIC and BOOTTIME clock behavior
  posix-timers: Unify MONOTONIC and BOOTTIME clock behavior
  timekeeping: Remove boot time specific code
  Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior
  timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock
  timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock
  timekeeping/ntp: Determine the multiplier directly from NTP tick length
  timekeeping/ntp: Don't align NTP frequency adjustments to ticks
  clocksource: Use ATTRIBUTE_GROUPS
  clocksource: Use DEVICE_ATTR_RW/RO/WO to define device attributes
  clocksource: Don't walk the clocksource list for empty override
2018-04-04 14:50:29 -07:00
Linus Torvalds 5bb053bef8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Support offloading wireless authentication to userspace via
    NL80211_CMD_EXTERNAL_AUTH, from Srinivas Dasari.

 2) A lot of work on network namespace setup/teardown from Kirill Tkhai.
    Setup and cleanup of namespaces now all run asynchronously and thus
    performance is significantly increased.

 3) Add rx/tx timestamping support to mv88e6xxx driver, from Brandon
    Streiff.

 4) Support zerocopy on RDS sockets, from Sowmini Varadhan.

 5) Use denser instruction encoding in x86 eBPF JIT, from Daniel
    Borkmann.

 6) Support hw offload of vlan filtering in mvpp2 dreiver, from Maxime
    Chevallier.

 7) Support grafting of child qdiscs in mlxsw driver, from Nogah
    Frankel.

 8) Add packet forwarding tests to selftests, from Ido Schimmel.

 9) Deal with sub-optimal GSO packets better in BBR congestion control,
    from Eric Dumazet.

10) Support 5-tuple hashing in ipv6 multipath routing, from David Ahern.

11) Add path MTU tests to selftests, from Stefano Brivio.

12) Various bits of IPSEC offloading support for mlx5, from Aviad
    Yehezkel, Yossi Kuperman, and Saeed Mahameed.

13) Support RSS spreading on ntuple filters in SFC driver, from Edward
    Cree.

14) Lots of sockmap work from John Fastabend. Applications can use eBPF
    to filter sendmsg and sendpage operations.

15) In-kernel receive TLS support, from Dave Watson.

16) Add XDP support to ixgbevf, this is significant because it should
    allow optimized XDP usage in various cloud environments. From Tony
    Nguyen.

17) Add new Intel E800 series "ice" ethernet driver, from Anirudh
    Venkataramanan et al.

18) IP fragmentation match offload support in nfp driver, from Pieter
    Jansen van Vuuren.

19) Support XDP redirect in i40e driver, from Björn Töpel.

20) Add BPF_RAW_TRACEPOINT program type for accessing the arguments of
    tracepoints in their raw form, from Alexei Starovoitov.

21) Lots of striding RQ improvements to mlx5 driver with many
    performance improvements, from Tariq Toukan.

22) Use rhashtable for inet frag reassembly, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1678 commits)
  net: mvneta: improve suspend/resume
  net: mvneta: split rxq/txq init and txq deinit into SW and HW parts
  ipv6: frags: fix /proc/sys/net/ipv6/ip6frag_low_thresh
  net: bgmac: Fix endian access in bgmac_dma_tx_ring_free()
  net: bgmac: Correctly annotate register space
  route: check sysctl_fib_multipath_use_neigh earlier than hash
  fix typo in command value in drivers/net/phy/mdio-bitbang.
  sky2: Increase D3 delay to sky2 stops working after suspend
  net/mlx5e: Set EQE based as default TX interrupt moderation mode
  ibmvnic: Disable irqs before exiting reset from closed state
  net: sched: do not emit messages while holding spinlock
  vlan: also check phy_driver ts_info for vlan's real device
  Bluetooth: Mark expected switch fall-throughs
  Bluetooth: Set HCI_QUIRK_SIMULTANEOUS_DISCOVERY for BTUSB_QCA_ROME
  Bluetooth: btrsi: remove unused including <linux/version.h>
  Bluetooth: hci_bcm: Remove DMI quirk for the MINIX Z83-4
  sh_eth: kill useless check in __sh_eth_get_regs()
  sh_eth: add sh_eth_cpu_data::no_xdfar flag
  ipv6: factorize sk_wmem_alloc updates done by __ip6_append_data()
  ipv4: factorize sk_wmem_alloc updates done by __ip_append_data()
  ...
2018-04-03 14:04:18 -07:00
David S. Miller c0b458a946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:

1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
   MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE

2) In 'net-next' params->log_rq_size is renamed to be
   params->log_rq_mtu_frames.

3) In 'net-next' params->hard_mtu is added.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-01 19:49:34 -04:00
Andrey Ignatov 5e43f899b0 bpf: Check attach type at prog load time
== The problem ==

There are use-cases when a program of some type can be attached to
multiple attach points and those attach points must have different
permissions to access context or to call helpers.

E.g. context structure may have fields for both IPv4 and IPv6 but it
doesn't make sense to read from / write to IPv6 field when attach point
is somewhere in IPv4 stack.

Same applies to BPF-helpers: it may make sense to call some helper from
some attach point, but not from other for same prog type.

== The solution ==

Introduce `expected_attach_type` field in in `struct bpf_attr` for
`BPF_PROG_LOAD` command. If scenario described in "The problem" section
is the case for some prog type, the field will be checked twice:

1) At load time prog type is checked to see if attach type for it must
   be known to validate program permissions correctly. Prog will be
   rejected with EINVAL if it's the case and `expected_attach_type` is
   not specified or has invalid value.

2) At attach time `attach_type` is compared with `expected_attach_type`,
   if prog type requires to have one, and, if they differ, attach will
   be rejected with EINVAL.

The `expected_attach_type` is now available as part of `struct bpf_prog`
in both `bpf_verifier_ops->is_valid_access()` and
`bpf_verifier_ops->get_func_proto()` () and can be used to check context
accesses and calls to helpers correspondingly.

Initially the idea was discussed by Alexei Starovoitov <ast@fb.com> and
Daniel Borkmann <daniel@iogearbox.net> here:
https://marc.info/?l=linux-netdev&m=152107378717201&w=2

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-31 02:14:44 +02:00
Ingo Molnar 2d074918fb Merge branch 'perf/urgent' into perf/core
Conflicts:
	kernel/events/hw_breakpoint.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-29 16:03:48 +02:00
Alexei Starovoitov c4f6699dfc bpf: introduce BPF_RAW_TRACEPOINT
Introduce BPF_PROG_TYPE_RAW_TRACEPOINT bpf program type to access
kernel internal arguments of the tracepoints in their raw form.

>From bpf program point of view the access to the arguments look like:
struct bpf_raw_tracepoint_args {
       __u64 args[0];
};

int bpf_prog(struct bpf_raw_tracepoint_args *ctx)
{
  // program can read args[N] where N depends on tracepoint
  // and statically verified at program load+attach time
}

kprobe+bpf infrastructure allows programs access function arguments.
This feature allows programs access raw tracepoint arguments.

Similar to proposed 'dynamic ftrace events' there are no abi guarantees
to what the tracepoints arguments are and what their meaning is.
The program needs to type cast args properly and use bpf_probe_read()
helper to access struct fields when argument is a pointer.

For every tracepoint __bpf_trace_##call function is prepared.
In assembler it looks like:
(gdb) disassemble __bpf_trace_xdp_exception
Dump of assembler code for function __bpf_trace_xdp_exception:
   0xffffffff81132080 <+0>:     mov    %ecx,%ecx
   0xffffffff81132082 <+2>:     jmpq   0xffffffff811231f0 <bpf_trace_run3>

where

TRACE_EVENT(xdp_exception,
        TP_PROTO(const struct net_device *dev,
                 const struct bpf_prog *xdp, u32 act),

The above assembler snippet is casting 32-bit 'act' field into 'u64'
to pass into bpf_trace_run3(), while 'dev' and 'xdp' args are passed as-is.
All of ~500 of __bpf_trace_*() functions are only 5-10 byte long
and in total this approach adds 7k bytes to .text.

This approach gives the lowest possible overhead
while calling trace_xdp_exception() from kernel C code and
transitioning into bpf land.
Since tracepoint+bpf are used at speeds of 1M+ events per second
this is valuable optimization.

The new BPF_RAW_TRACEPOINT_OPEN sys_bpf command is introduced
that returns anon_inode FD of 'bpf-raw-tracepoint' object.

The user space looks like:
// load bpf prog with BPF_PROG_TYPE_RAW_TRACEPOINT type
prog_fd = bpf_prog_load(...);
// receive anon_inode fd for given bpf_raw_tracepoint with prog attached
raw_tp_fd = bpf_raw_tracepoint_open("xdp_exception", prog_fd);

Ctrl-C of tracing daemon or cmdline tool that uses this feature
will automatically detach bpf program, unload it and
unregister tracepoint probe.

On the kernel side the __bpf_raw_tp_map section of pointers to
tracepoint definition and to __bpf_trace_*() probe function is used
to find a tracepoint with "xdp_exception" name and
corresponding __bpf_trace_xdp_exception() probe function
which are passed to tracepoint_probe_register() to connect probe
with tracepoint.

Addition of bpf_raw_tracepoint doesn't interfere with ftrace and perf
tracepoint mechanisms. perf_event_open() can be used in parallel
on the same tracepoint.
Multiple bpf_raw_tracepoint_open("xdp_exception", prog_fd) are permitted.
Each with its own bpf program. The kernel will execute
all tracepoint probes and all attached bpf programs.

In the future bpf_raw_tracepoints can be extended with
query/introspection logic.

__bpf_raw_tp_map section logic was contributed by Steven Rostedt

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-28 22:55:19 +02:00
Rohit Visavalia 13cf912b2d tracing: Block comments should align the * on each line
Resolved Block comments use * on subsequent lines checkpatch warning.
Issue found by checkpatch.

Signed-off-by: Rohit Visavalia <rohit.visavalia@softnautics.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-27 09:51:23 +02:00
Joe Perches 447a5647c9 treewide: Align function definition open/close braces
Some functions definitions have either the initial open brace and/or
the closing brace outside of column 1.

Move those braces to column 1.

This allows various function analyzers like gnu complexity to work
properly for these modified functions.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-26 11:13:09 +02:00
Linus Torvalds 99fec39e77 The documentation for kprobe events says that symbol offets can
take both a + and - sign to get to befor and after the symbol address.
 But in actuality, the code does not support the minus. This fixes
 that issue, and adds a few more selftests to kprobe events.
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlq1e6IUHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUlA2gv/WJiLQC8NvZhjIuQAmhohoW2ejkf/
 rxW8AWCArcUwtqPxpeXAg+SzDIxqtkpUw2PkuivVkzugV/9cAdM+o4yogV8aV32w
 IYix77NxdaIiFNkMCrPYIBH8Bv7TubKUNEe5j+ChFGv90E98Cy2qFLXLXM8wkapq
 FMQ9PlLr9KumRwGeCSqGx1grVLv3uWlv85XY+pTHdtoeivL/maiemISgg0HE4UVc
 ovdZBMmiQBKjc727VgdRpkXWVA+sCoIhAzlkB5cSdDoYx5pHZi23qi5ZHjvlIIRz
 dD50lI41svFd4Q+WxcKxgMWqSS0NytnjQGfO4rU+3A4ZGYbjjWPtrTGxluX6Tx3C
 vOL6SYmD8FtU9c4WvgRLUsDzUrH2plDZOeL2jJSKFHwmB3USKLhYo7I4M/VYBXII
 K3kq/8ln3vq5NbyCcpQSHC5PuRW9pSKjiLUuXMEEKTlK+Aa+Jmvx7SJWp0l6gY0q
 BSMxInLOk5E+eechCkO/S9bugwlJYw2i7Oiq
 =SWSP
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull kprobe fixes from Steven Rostedt:
 "The documentation for kprobe events says that symbol offets can take
  both a + and - sign to get to befor and after the symbol address.

  But in actuality, the code does not support the minus. This fixes that
  issue, and adds a few more selftests to kprobe events"

* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests: ftrace: Add a testcase for probepoint
  selftests: ftrace: Add a testcase for string type with kprobe_event
  selftests: ftrace: Add probe event argument syntax testcase
  tracing: probeevent: Fix to support minus offset from symbol
2018-03-23 15:34:18 -07:00
Masami Hiramatsu c5d343b6b7 tracing: probeevent: Fix to support minus offset from symbol
In Documentation/trace/kprobetrace.txt, it says

 @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)

However, the parser doesn't parse minus offset correctly, since
commit 2fba0c8867 ("tracing/kprobes: Fix probe offset to be
unsigned") drops minus ("-") offset support for kprobe probe
address usage.

This fixes the traceprobe_split_symbol_offset() to parse minus
offset again with checking the offset range, and add a minus
offset check in kprobe probe address usage.

Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 2fba0c8867 ("tracing/kprobes: Fix probe offset to be unsigned")
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-23 12:02:37 -04:00
David S. Miller 03fe2debbb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Fun set of conflict resolutions here...

For the mac80211 stuff, these were fortunately just parallel
adds.  Trivially resolved.

In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.

In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.

The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.

The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:

====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch.  This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
            drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
            (IB/mlx5: Fix cleanup order on unload) added to for-rc and
            commit b5ca15ad7e (IB/mlx5: Add proper representors support)
            add as part of the devel cycle both needed to modify the
            init/de-init functions used by mlx5.  To support the new
            representors, the new functions added by the cleanup patch
            needed to be made non-static, and the init/de-init list
            added by the representors patch needed to be modified to
            match the init/de-init list changes made by the cleanup
            patch.
    Updates:
            drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
            prototypes added by representors patch to reflect new function
            names as changed by cleanup patch
            drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
            stage list to match new order from cleanup patch
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 11:31:58 -04:00
Dan Carpenter 5e4cf2bf6d tracing: Fix a potential NULL dereference
We forgot to set the error code on this path so we return ERR_PTR(0)
which is NULL.  It results in a NULL dereference in the caller.

Link: http://lkml.kernel.org/r/20180323113735.GC28518@mwanda

Fixes: 100719dcef ("tracing: Add simple expression support to hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-23 11:15:20 -04:00
Yonghong Song f005afede9 trace/bpf: remove helper bpf_perf_prog_read_value from tracepoint type programs
Commit 4bebdc7a85 ("bpf: add helper bpf_perf_prog_read_value")
added helper bpf_perf_prog_read_value so that perf_event type program
can read event counter and enabled/running time.
This commit, however, introduced a bug which allows this helper
for tracepoint type programs. This is incorrect as bpf_perf_prog_read_value
needs to access perf_event through its bpf_perf_event_data_kern type context,
which is not available for tracepoint type program.

This patch fixed the issue by separating bpf_func_proto between tracepoint
and perf_event type programs and removed bpf_perf_prog_read_value
from tracepoint func prototype.

Fixes: 4bebdc7a85 ("bpf: add helper bpf_perf_prog_read_value")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-20 23:08:52 +01:00
Steven Rostedt (VMware) 80765597bc tracing: Rewrite filter logic to be simpler and faster
Al Viro reviewed the filter logic of ftrace trace events and found it to be
very troubling. It creates a binary tree based on the logic operators and
walks it during tracing. He sent myself and Tom Zanussi a long explanation
(and formal proof) of how to do the string parsing better and end up with a
program array that can be simply iterated to come up with the correct
results.

I took his ideas and his pseudo code and rewrote the filter logic based on
them. In doing so, I was able to remove a lot of code, and have a much more
condensed filter logic in the process. I wrote a very long comment
describing the methadology that Al proposed in my own words. For more info
on how this works, read the comment above predicate_parse().

Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-14 12:35:39 -04:00
Steven Rostedt (VMware) 478325f188 tracing: Clean up and document pred_funcs_##type creation and use
The pred_funcs_##type arrays consist of five functions that are assigned
based on the ops. The array must be in the same order of the ops each
function represents. The PRED_FUNC_START macro denotes the op enum that
starts the op that maps to the pred_funcs_##type arrays. This is all very
subtle and prone to bugs if the code is changed.

Add comments describing how PRED_FUNC_START and pred_funcs_##type array is
used, and also a PRED_FUNC_MAX that is the maximum number of functions in
the arrays.

Clean up select_comparison_fn() that assigns the predicates to the
pred_funcs_##type array function as well as add protection in case an op is
passed in that does not map correctly to the array.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-14 12:35:20 -04:00
Steven Rostedt (VMware) e9baef0d86 tracing: Combine enum and arrays into single macro in filter code
Instead of having a separate enum that is the index into another array, like
a string array, make a single macro that combines them into a single list,
and then the two can not get out of sync. This makes it easier to add and
remove items.

The macro trick is:

 #define DOGS				\
  C( JACK,     "Jack Russell")		\
  C( ITALIAN,  "Italian Greyhound")	\
  C( GERMAN,   "German Shepherd")

 #undef C
 #define C(a, b) a

 enum { DOGS };

 #undef C
 #define C(a, b) b

 static char dogs[] = { DOGS };

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-14 12:32:18 -04:00
Thomas Gleixner 92af4dcb4e tracing: Unify the "boot" and "mono" tracing clocks
Unify the "boot" and "mono" tracing clocks and document the new behaviour.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20180301165150.489635255@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-13 07:34:23 +01:00
Steven Rostedt (VMware) 567f6989fd tracing: Embed replace_filter_string() helper function
The replace_filter_string() frees the current string and then copies a given
string. But in the two locations that it was used, the allocation happened
right after the filter was allocated (nothing to replace). There's no need
for this to be a helper function. Embedding the allocation in the two places
where it was called will make changing the code in the future easier.

Also make the variable consistent (always use "filter_string" as the name,
as it was used in one instance as "filter_str")

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:07 -05:00
Steven Rostedt (VMware) 404a3add43 tracing: Only add filter list when needed
replace_system_preds() creates a filter list to free even when it doesn't
really need to have it. Only save filters that require synchronize_sched()
in the filter list to free. This will allow the code to be updated a bit
easier in the future.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:07 -05:00
Steven Rostedt (VMware) c7399708b3 tracing: Remove filter allocator helper
The __alloc_filter() function does nothing more that allocate the filter.
There's no reason to have it as a helper function.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:06 -05:00
Steven Rostedt (VMware) 559d421267 tracing: Use trace_seq instead of open code string appending
The filter code does open code string appending to produce an error message.
Instead it can be simplified by using trace_seq function helpers.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:06 -05:00
Steven Rostedt (VMware) a0ff08fd4e tracing: Remove BUG_ON() from append_filter_string()
There's no reason to BUG if there's a bug in the filtering code. Simply do a
warning and return.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:05 -05:00
Tom Zanussi 89e270c1df tracing: Add inter-event blurb to HIST_TRIGGERS config option
So that users know that inter-event tracing is supported as part of
the HIST_TRIGGERS option, include text to that effect in the help
text.

Link: http://lkml.kernel.org/r/a38e24231d8d980be636b56d35814570acfd167a.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:05 -05:00
Steven Rostedt (VMware) 4708abc6c6 tracing: Use the ring-buffer nesting to allow synthetic events to be traced
Synthetic events can be done within the recording of other events. Notify
the ring buffer via ring_buffer_nest_start() and ring_buffer_nest_end() that
this is intended and not to block it due to its recursion protection.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:04 -05:00
Steven Rostedt (VMware) 8e012066fe ring-buffer: Add nesting for adding events within events
The ring-buffer code has recusion protection in case tracing ends up tracing
itself, the ring-buffer will detect that it was called at the same context
(normal, softirq, interrupt or NMI), and not continue to record the event.

With the histogram synthetic events, they are called while tracing another
event at the same context. The recusion protection triggers because it
detects tracing at the same context and stops it.

Add ring_buffer_nest_start() and ring_buffer_nest_end() that will notify the
ring buffer that a trace is about to happen within another trace and that it
is intended, and not to trigger the recursion blocking.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:04 -05:00
Tom Zanussi a4072fe85b tracing: Add a clock attribute for hist triggers
The default clock if timestamps are used in a histogram is "global".
If timestamps aren't used, the clock is irrelevant.

Use the "clock=" param only if you want to override the default
"global" clock for a histogram with timestamps.

Link: http://lkml.kernel.org/r/427bed1389c5d22aa40c3e0683e30cc3d151e260.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:03 -05:00
Tom Zanussi d71bd34d78 tracing: Make tracing_set_clock() non-static
Allow tracing code outside of trace.c to access tracing_set_clock().

Some applications may require a particular clock in order to function
properly, such as latency calculations.

Also, add an accessor returning the current clock string.

Link: http://lkml.kernel.org/r/6d1c53e9ee2163f54e1849f5376573f54f0e6009.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:03 -05:00
Tom Zanussi f404da6e1d tracing: Add 'last error' error facility for hist triggers
With the addition of variables and actions, it's become necessary to
provide more detailed error information to users about syntax errors.

Add a 'last error' facility accessible via the erroring event's 'hist'
file.  Reading the hist file after an error will display more detailed
information about what went wrong, if information is available.  This
extended error information will be available until the next hist
trigger command for that event.

  # echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
  echo: write error: Invalid argument

  # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist

  ERROR: Couldn't yyy: zzz
  Last command: xxx

Also add specific error messages for variable and action errors.

Link: http://lkml.kernel.org/r/64e9c422fc8aeafcc2f7a3b4328c0cffe7969129.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:02 -05:00
Tom Zanussi 7e8b88a30b tracing: Add hist trigger support for variable reference aliases
Add support for alias=$somevar where alias can be used as
onmatch.xxx($alias).

Aliases are a way of creating a new name for an existing variable, for
flexibly in making naming more clear in certain cases.  For example in
the below the user perhaps feels that using $new_lat in the synthetic
event invocation is opaque or doesn't fit well stylistically with
previous triggers, so creates an alias of $new_lat named $latency and
uses that in the call instead:

  # echo 'hist:keys=next_pid:new_lat=common_timestamp.usecs' >
    /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

  # echo 'hist:keys=pid:latency=$new_lat:
    onmatch(sched.sched_switch).wake2($latency,pid)' >
    /sys/kernel/debug/tracing/events/synthetic/wake1/trigger

Link: http://lkml.kernel.org/r/ef20a65d921af3a873a6f1e8c71407c926d5586f.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:01 -05:00
Tom Zanussi 8b7622bf94 tracing: Add cpu field for hist triggers
A common key to use in a histogram is the cpuid - add a new cpu
'synthetic' field named 'cpu' for that purpose.

Link: http://lkml.kernel.org/r/89537645bfc957e0d76e2cacf5f0ada88691a6cc.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:01 -05:00
Tom Zanussi ec5ce09875 tracing: Allow whitespace to surround hist trigger filter
The existing code only allows for one space before and after the 'if'
specifying the filter for a hist trigger.  Add code to make that more
permissive as far as whitespace goes.  Specifically, we want to allow
spaces in the trigger itself now that we have additional syntax
(onmatch/onmax) where spaces are more natural e.g. spaces after commas
in param lists.

Link: http://lkml.kernel.org/r/1053090c3c308d4f431accdeb59dff4b511d4554.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:00 -05:00
Tom Zanussi 50450603ec tracing: Add 'onmax' hist trigger action support
Add an 'onmax(var).save(field,...)' hist trigger action which is
invoked whenever an event exceeds the current maximum.

The end result is that the trace event fields or variables specified
as the onmax.save() params will be saved if 'var' exceeds the current
maximum for that hist trigger entry.  This allows context from the
event that exhibited the new maximum to be saved for later reference.
When the histogram is displayed, additional fields displaying the
saved values will be printed.

As an example the below defines a couple of hist triggers, one for
sched_wakeup and another for sched_switch, keyed on pid.  Whenever a
sched_wakeup occurs, the timestamp is saved in the entry corresponding
to the current pid, and when the scheduler switches back to that pid,
the timestamp difference is calculated.  If the resulting latency
exceeds the current maximum latency, the specified save() values are
saved:

    # echo 'hist:keys=pid:ts0=common_timestamp.usecs \
        if comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger

    # echo 'hist:keys=next_pid:\
      wakeup_lat=common_timestamp.usecs-$ts0:\
      onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm) \
        if next_comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

When the histogram is displayed, the max value and the saved values
corresponding to the max are displayed following the rest of the
fields:

    # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist

      { next_pid:       3728 } hitcount:        199 \
        max:        123  next_comm: cyclictest  prev_pid:          0 \
	prev_prio:        120  prev_comm: swapper/3
      { next_pid:       3730 } hitcount:       1321 \
        max:         15  next_comm: cyclictest  prev_pid:          0 \
	prev_prio:        120  prev_comm: swapper/1
      { next_pid:       3729 } hitcount:       1973\
        max:         25  next_comm: cyclictest  prev_pid:          0  \
	prev_prio:        120  prev_comm: swapper/0

    Totals:
        Hits: 3493
        Entries: 3
	Dropped: 0

Link: http://lkml.kernel.org/r/006907f71b1e839bb059337ec3c496f84fcb71de.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:06:00 -05:00
Tom Zanussi c282a386a3 tracing: Add 'onmatch' hist trigger action support
Add an 'onmatch(matching.event).<synthetic_event_name>(param list)'
hist trigger action which is invoked with the set of variables or
event fields named in the 'param list'.  The result is the generation
of a synthetic event that consists of the values contained in those
variables and/or fields at the time the invoking event was hit.

As an example the below defines a simple synthetic event using a
variable defined on the sched_wakeup_new event, and shows the event
definition with unresolved fields, since the sched_wakeup_new event
with the testpid variable hasn't been defined yet:

    # echo 'wakeup_new_test pid_t pid; int prio' >> \
      /sys/kernel/debug/tracing/synthetic_events

    # cat /sys/kernel/debug/tracing/synthetic_events
      wakeup_new_test pid_t pid; int prio

The following hist trigger both defines a testpid variable and
specifies an onmatch() trace action that uses that variable along with
a non-variable field to generate a wakeup_new_test synthetic event
whenever a sched_wakeup_new event occurs, which because of the 'if
comm == "cyclictest"' filter only happens when the executable is
cyclictest:

    # echo 'hist:testpid=pid:keys=$testpid:\
      onmatch(sched.sched_wakeup_new).wakeup_new_test($testpid, prio) \
        if comm=="cyclictest"' >> \
      /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger

Creating and displaying a histogram based on those events is now just
a matter of using the fields and new synthetic event in the
tracing/events/synthetic directory, as usual:

    # echo 'hist:keys=pid,prio:sort=pid,prio' >> \
      /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger

Link: http://lkml.kernel.org/r/8c2a574bcb7530c876629c901ecd23911b14afe8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:59 -05:00
Tom Zanussi 02205a6752 tracing: Add support for 'field variables'
Users should be able to directly specify event fields in hist trigger
'actions' rather than being forced to explicitly create a variable for
that purpose.

Add support allowing fields to be used directly in actions, which
essentially does just that - creates 'invisible' variables for each
bare field specified in an action.  If a bare field refers to a field
on another (matching) event, it even creates a special histogram for
the purpose (since variables can't be defined on an existing histogram
after histogram creation).

Here's a simple example that demonstrates both.  Basically the
onmatch() action creates a list of variables corresponding to the
parameters of the synthetic event to be generated, and then uses those
values to generate the event.  So for the wakeup_latency synthetic
event 'call' below the first param, $wakeup_lat, is a variable defined
explicitly on sched_switch, where 'next_pid' is just a normal field on
sched_switch, and prio is a normal field on sched_waking.

Since the mechanism works on variables, those two normal fields just
have 'invisible' variables created internally for them.  In the case of
'prio', which is on another event, we actually need to create an
additional hist trigger and define the invisible variable on that, since
once a hist trigger is defined, variables can't be added to it later.

  echo 'wakeup_latency u64 lat; pid_t pid; int prio' >>
       /sys/kernel/debug/tracing/synthetic_events

  echo 'hist:keys=pid:ts0=common_timestamp.usecs >>
       /sys/kernel/debug/tracing/events/sched/sched_waking/trigger

echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:
      onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,prio)
            >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger

Link: http://lkml.kernel.org/r/8e8dcdac1ea180ed7a3689e1caeeccede9dc42b3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:59 -05:00
Tom Zanussi 4b147936fa tracing: Add support for 'synthetic' events
Synthetic events are user-defined events generated from hist trigger
variables saved from one or more other events.

To define a synthetic event, the user writes a simple specification
consisting of the name of the new event along with one or more
variables and their type(s), to the tracing/synthetic_events file.

For instance, the following creates a new event named 'wakeup_latency'
with 3 fields: lat, pid, and prio:

    # echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> \
      /sys/kernel/debug/tracing/synthetic_events

Reading the tracing/synthetic_events file lists all the
currently-defined synthetic events, in this case the event we defined
above:

    # cat /sys/kernel/debug/tracing/synthetic_events
    wakeup_latency u64 lat; pid_t pid; int prio

At this point, the synthetic event is ready to use, and a histogram
can be defined using it:

    # echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \
    /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger

The new event is created under the tracing/events/synthetic/ directory
and looks and behaves just like any other event:

    # ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency
      enable  filter  format  hist  id  trigger

Although a histogram can be defined for it, nothing will happen until
an action tracing that event via the trace_synth() function occurs.
The trace_synth() function is very similar to all the other trace_*
invocations spread throughout the kernel, except in this case the
trace_ function and its corresponding tracepoint isn't statically
generated but defined by the user at run-time.

How this can be automatically hooked up via a hist trigger 'action' is
discussed in a subsequent patch.

Link: http://lkml.kernel.org/r/c68df2284b7d172669daf9be29db62ad49bbc559.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[fix noderef.cocci warnings, sizeof pointer for kcalloc of event->fields]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi 0212e2aa30 tracing: Add hist trigger action hook
Add a hook for executing extra actions whenever a histogram entry is
added or updated.

The default 'action' when a hist entry is added to a histogram is to
update the set of values associated with it.  Some applications may
want to perform additional actions at that point, such as generate
another event, or compare and save a maximum.

Add a simple framework for doing that; specific actions will be
implemented on top of it in later patches.

Link: http://lkml.kernel.org/r/9482ba6a3eaf5ca6e60954314beacd0e25c05b24.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi 067fe038e7 tracing: Add variable reference handling to hist triggers
Add the necessary infrastructure to allow the variables defined on one
event to be referenced in another.  This allows variables set by a
previous event to be referenced and used in expressions combining the
variable values saved by that previous event and the event fields of
the current event.  For example, here's how a latency can be
calculated and saved into yet another variable named 'wakeup_lat':

    # echo 'hist:keys=pid,prio:ts0=common_timestamp ...
    # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ...

In the first event, the event's timetamp is saved into the variable
ts0.  In the next line, ts0 is subtracted from the second event's
timestamp to produce the latency.

Further users of variable references will be described in subsequent
patches, such as for instance how the 'wakeup_lat' variable above can
be displayed in a latency histogram.

Link: http://lkml.kernel.org/r/b1d3e6975374e34d501ff417c20189c3f9b2c7b8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00
Tom Zanussi 19a9facd0f tracing: Add hist_field 'type' field
Future support for synthetic events requires hist_field 'type'
information, so add a field for that.

Also, make other hist_field attribute usage consistent (size,
is_signed, etc).

Link: http://lkml.kernel.org/r/3fd12a2e86316b05151ba0d7c68268e780af2c9d.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:57 -05:00
Tom Zanussi df35d93bbf tracing: Pass tracing_map_elt to hist_field accessor functions
Some accessor functions, such as for variable references, require
access to a corrsponding tracing_map_elt.

Add a tracing_map_elt param to the function signature and update the
accessor functions accordingly.

Link: http://lkml.kernel.org/r/e0f292b068e9e4948da1d5af21b5ae0efa9b5717.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:57 -05:00
Tom Zanussi af6a29bcaf tracing: Generalize per-element hist trigger data
Up until now, hist triggers only needed per-element support for saving
'comm' data, which was saved directly as a private data pointer.

In anticipation of the need to save other data besides 'comm', add a
new hist_elt_data struct for the purpose, and switch the current
'comm'-related code over to that.

Link: http://lkml.kernel.org/r/4502c338c965ddf5fc19fb1ec4764391e001ed4b.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:56 -05:00
Tom Zanussi 100719dcef tracing: Add simple expression support to hist triggers
Add support for simple addition, subtraction, and unary expressions
(-(expr) and expr, where expr = b-a, a+b, a+b+c) to hist triggers, in
order to support a minimal set of useful inter-event calculations.

These operations are needed for calculating latencies between events
(timestamp1-timestamp0) and for combined latencies (latencies over 3
or more events).

In the process, factor out some common code from key and value
parsing.

Link: http://lkml.kernel.org/r/9a9308ead4fe32a433d9c7e95921fb798394f6b2.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[kbuild test robot fix, add static to parse_atom()]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
[ Replaced '//' comments with normal /* */ comments ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:56 -05:00
Tom Zanussi 2ece94fbd2 tracing: Move get_hist_field_flags()
Move get_hist_field_flags() to make it more easily accessible for new
code (and keep the move separate from new functionality).

Link: http://lkml.kernel.org/r/32470f0a7047ec7a6e84ba5ec89d6142cc6ede7d.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:55 -05:00
Tom Zanussi 1a361dfcf2 tracing: Account for variables in named trigger compatibility
Named triggers must also have the same set of variables in order to be
considered compatible - update the trigger match test to account for
that.

The reason for this requirement is that named triggers with variables
are meant to allow one or more events to set the same variable.

Link: http://lkml.kernel.org/r/a17eae6328a99917f9d5c66129c9fcd355279ee9.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:55 -05:00
Tom Zanussi 30350d65ac tracing: Add variable support to hist triggers
Add support for saving the value of a current event's event field by
assigning it to a variable that can be read by a subsequent event.

The basic syntax for saving a variable is to simply prefix a unique
variable name not corresponding to any keyword along with an '=' sign
to any event field.

Both keys and values can be saved and retrieved in this way:

    # echo 'hist:keys=next_pid:vals=$ts0:ts0=common_timestamp ...
    # echo 'hist:timer_pid=common_pid:key=$timer_pid ...'

If a variable isn't a key variable or prefixed with 'vals=', the
associated event field will be saved in a variable but won't be summed
as a value:

    # echo 'hist:keys=next_pid:ts1=common_timestamp:...

Multiple variables can be assigned at the same time:

    # echo 'hist:keys=pid:vals=$ts0,$b,field2:ts0=common_timestamp,b=field1 ...

Multiple (or single) variables can also be assigned at the same time
using separate assignments:

    # echo 'hist:keys=pid:vals=$ts0:ts0=common_timestamp:b=field1:c=field2 ...

Variables set as above can be used by being referenced from another
event, as described in a subsequent patch.

Link: http://lkml.kernel.org/r/fc93c4944d9719dbcb1d0067be627d44e98e2adc.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:54 -05:00
Tom Zanussi 860f9f6b02 tracing: Add usecs modifier for hist trigger timestamps
Appending .usecs onto a common_timestamp field will cause the
timestamp value to be in microseconds instead of the default
nanoseconds.  A typical latency histogram using usecs would look like
this:

   # echo 'hist:keys=pid,prio:ts0=common_timestamp.usecs ...
   # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 ...

This also adds an external trace_clock_in_ns() to trace.c for the
timestamp conversion.

Link: http://lkml.kernel.org/r/4e813705a170b3e13e97dc3135047362fb1a39f3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:54 -05:00
Tom Zanussi b559d003a2 tracing: Add hist_data member to hist_field
Allow hist_data access via hist_field.  Some users of hist_fields
require or will require more access to the associated hist_data.

Link: http://lkml.kernel.org/r/d04cd0768f5228ebb4ac0ba4a847bc4d14d4826f.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:53 -05:00
Tom Zanussi 2734b62952 tracing: Add per-element variable support to tracing_map
In order to allow information to be passed between trace events, add
support for per-element variables to tracing_map.  This provides a
means for histograms to associate a value or values with an entry when
it's saved or updated, and retrieved by a subsequent event occurrences.

Variables can be set using tracing_map_set_var() and read using
tracing_map_read_var().  tracing_map_var_set() returns true or false
depending on whether or not the variable has been set or not, which is
important for event-matching applications.

tracing_map_read_var_once() reads the variable and resets it to the
'unset' state, implementing read-once variables, which are also
important for event-matching uses.

Link: http://lkml.kernel.org/r/7fa001108252556f0c6dd9d63145eabfe3370d1a.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:53 -05:00
Tom Zanussi ad42febe51 tracing: Add hist trigger timestamp support
Add support for a timestamp event field.  This is actually a 'pseudo-'
event field in that it behaves like it's part of the event record, but
is really part of the corresponding ring buffer event.

To make use of the timestamp field, users can specify
"common_timestamp" as a field name for any histogram.  Note that this
doesn't make much sense on its own either as either a key or value,
but needs to be supported even so, since follow-on patches will add
support for making use of this field in time deltas.  The
common_timestamp 'field' is not a bona fide event field - so you won't
find it in the event description - but rather it's a synthetic field
that can be used like a real field.

Note that the use of this field requires the ring buffer be put into
'absolute timestamp' mode, which saves the complete timestamp for each
event rather than an offset.  This mode will be enabled if and only if
a histogram makes use of the "common_timestamp" field.

Link: http://lkml.kernel.org/r/97afbd646ed146e26271f3458b4b33e16d7817c2.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
[kasan use-after-free fix]
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi 9b1ae035c9 tracing: Break out hist trigger assignment parsing
This will make it easier to add variables, and makes the parsing code
cleaner regardless.

Link: http://lkml.kernel.org/r/e574b3291bbe15e35a4dfc87e5395aa715701c98.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi fbd302cbeb tracing: Add ring buffer event param to hist field functions
Some events such as timestamps require access to a ring_buffer_event
struct; add a param so that hist field functions can access that.

Link: http://lkml.kernel.org/r/2ff4af18e72b6002eb86b26b2a7f39cef7d1dfe4.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:52 -05:00
Tom Zanussi 1ac4f51c0e tracing: Give event triggers access to ring_buffer_event
The ring_buffer event can provide a timestamp that may be useful to
various triggers - pass it into the handlers for that purpose.

Link: http://lkml.kernel.org/r/6de592683b59fa70ffa5d43d0109896623fc1367.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:51 -05:00
Tom Zanussi 2c1ea60b19 tracing: Add timestamp_mode trace file
Add a new option flag indicating whether or not the ring buffer is in
'absolute timestamp' mode.

Currently this is only set/unset by hist triggers that make use of a
common_timestamp.  As such, there's no reason to make this writeable
for users - its purpose is only to allow users to determine
unequivocally whether or not the ring buffer is in that mode (although
absolute timestamps can coexist with the normal delta timestamps, when
the ring buffer is in absolute mode, timestamps written while absolute
mode is in effect take up more space in the buffer, and are not as
efficient).

Link: http://lkml.kernel.org/r/e8aa7b1cde1cf15014e66545d06ac6ef2ebba456.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:51 -05:00
Tom Zanussi dc4e2801d4 ring-buffer: Redefine the unimplemented RINGBUF_TYPE_TIME_STAMP
RINGBUF_TYPE_TIME_STAMP is defined but not used, and from what I can
gather was reserved for something like an absolute timestamp feature
for the ring buffer, if not a complete replacement of the current
time_delta scheme.

This code redefines RINGBUF_TYPE_TIME_STAMP to implement absolute time
stamps.  Another way to look at it is that it essentially forces
extended time_deltas for all events.

The motivation for doing this is to enable time_deltas that aren't
dependent on previous events in the ring buffer, making it feasible to
use the ring_buffer_event timetamps in a more random-access way, for
purposes other than serial event printing.

To set/reset this mode, use tracing_set_timestamp_abs() from the
previous interface patch.

Link: http://lkml.kernel.org/r/477b362dba1ce7fab9889a1a8e885a62c472f041.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:50 -05:00
Tom Zanussi 00b4145298 ring-buffer: Add interface for setting absolute time stamps
Define a new function, tracing_set_time_stamp_abs(), which can be used
to enable or disable the use of absolute timestamps rather than time
deltas for a trace array.

Only the interface is added here; a subsequent patch will add the
underlying implementation.

Link: http://lkml.kernel.org/r/ce96119de44c7fe0ee44786d15254e9b493040d3.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:50 -05:00
Vedang Patel c193707dde tracing: Remove code which merges duplicates
We now have the logic to detect and remove duplicates in the
tracing_map hash table. The code which merges duplicates in the
histogram is redundant now. So, modify this code just to detect
duplicates. The duplication detection code is still kept to ensure
that any rare race condition which might cause duplicates does not go
unnoticed.

Link: http://lkml.kernel.org/r/55215cf59e2674391bdaf772fdafc4c393352b03.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:49 -05:00
Vedang Patel cbf4100efb tracing: Add support to detect and avoid duplicates
A duplicate in the tracing_map hash table is when 2 different entries
have the same key and, as a result, the key_hash. This is possible due
to a race condition in the algorithm. This race condition is inherent to
the algorithm and not a bug. This was fine because, until now, we were
only interested in the sum of all the values related to a particular
key (the duplicates are dealt with in tracing_map_sort_entries()). But,
with the inclusion of variables[1], we are interested in individual
values. So, it will not be clear what value to choose when
there are duplicates. So, the duplicates need to be removed.

The duplicates can occur in the code in the following scenarios:

- A thread is in the process of adding a new element. It has
successfully executed cmpxchg() and inserted the key. But, it is still
not done acquiring the trace_map_elt struct, populating it and storing
the pointer to the struct in the value field of tracing_map hash table.
If another thread comes in at this time and wants to add an element with
the same key, it will not see the current element and add a new one.

- There are multiple threads trying to execute cmpxchg at the same time,
one of the threads will succeed and the others will fail. The ones which
fail will go ahead increment 'idx' and add a new element there creating
a duplicate.

This patch detects and avoids the first condition by asking the thread
which detects the duplicate to loop one more time. There is also a
possibility of infinite loop if the thread which is trying to insert
goes to sleep indefinitely and the one which is trying to insert a new
element detects a duplicate. Which is why, the thread loops for
map_size iterations before returning NULL.

The second scenario is avoided by preventing the threads which failed
cmpxchg() from incrementing idx. This way, they will loop
around and check if the thread which succeeded in executing cmpxchg()
had the same key.

[1] http://lkml.kernel.org/r/cover.1498510759.git.tom.zanussi@linux.intel.com

Link: http://lkml.kernel.org/r/e178e89ec399240331d383bd5913d649713110f4.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:49 -05:00
Teng Qin 95da0cdb72 bpf: add support to read sample address in bpf program
This commit adds new field "addr" to bpf_perf_event_data which could be
read and used by bpf programs attached to perf events. The value of the
field is copied from bpf_perf_event_data_kern.addr and contains the
address value recorded by specifying sample_type with PERF_SAMPLE_ADDR
when calling perf_event_open.

Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-08 02:22:34 +01:00
Ingo Molnar 8af31363cd Linux 4.16-rc4
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlqceRweHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG59gH/0CVX4x6EobO/PQu
 CzLVtAoRGFuIghB6Gmbx3Q1Ck4sn4q2SqUKTtkf03yauRGvnJsEmd6wEZ8f2IOHy
 f30nX9s+4irzpQUIum4rH9KP6SMVJfNXlSVSisnamA6MbhPre3/NRcAIBUxdE4cK
 lP81TaT6Nvp5cOySlPjPdWSbN4B1froFQ6rZ/lvG406QzqCvKvlS39h6IYjOF7Ds
 zB/h3RkyuK9YyxFUO338RTEQ583esc0jTiTN4Pzb6nH3x8aTawDqGrwI2B4mkTLw
 vNSPPE2VW9to0cZX+J7TH+uusPNXIlHZCD9tXwqWe5M+sCrE2FuydnmpZIf1A2LY
 aWs0KQs=
 =4nyn
 -----END PGP SIGNATURE-----

Merge tag 'v4.16-rc4' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-06 07:30:22 +01:00
Ingo Molnar 7057bb975d Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-17 11:39:28 +01:00
Daniel Borkmann 9c481b908b bpf: fix bpf_prog_array_copy_to_user warning from perf event prog query
syzkaller tried to perform a prog query in perf_event_query_prog_array()
where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and
thus causing a warning due to failed kcalloc() allocation out of the
bpf_prog_array_copy_to_user() helper. Given we cannot attach more than
64 programs to a perf event, there's no point in allowing huge ids_len.
Therefore, allow a buffer that would fix the maximum number of ids and
also add a __GFP_NOWARN to the temporary ids buffer.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Fixes: 0911287ce3 ("bpf: fix bpf_prog_array_copy_to_user() issues")
Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-14 08:59:37 -08:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Linus Torvalds 8158c2ffa4 Al Viro discovered some breakage with the parsing of the set_ftrace_filter
as well as the removing of function probes.
 
 This fixes the code with Al's suggestions. I also added a few selftests
 to test the broken cases such that they wont happen again.
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlp9/g8UHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUkFaAwAl+BpQOOLY/vdivHZApyX75qc+Ysn
 yzMtz/9FffYsZiWaPp84iKCHpRKXzHIkmcNlZNWmitoHE6DY53+4l/CrlLgEius8
 FApkXnptFkhklfW1EhkXjt9pawcqFJhbYlGld93Bn/jvPOznpIhxDKcLqTJkD2M4
 DUwJLv0p8vh2uUSMUPLrNGDrHb6lu/sO0zEcf1HyWPEMo/6r903aG99cKuCLOnjF
 1jSwQ0DivTz+BjXrt+OVObzm1RFCvBP9SK0WRoPTzsmBx6EWEexCNiwyXxFJfRXn
 GfYRMDllkJ7i5ATCppdDHZyIdoCAF+iFLh5UK/Kl/cG6w8c2FATm3HOBkgr12as6
 LVSS475FfxjaMoT73fYszQdHevc9dI3aIh4GYjThH/mw2KSwBq+1GjRf4Jqa/1pt
 crlDsQMQTXMx9pGN+DOZR7NDkj9xTyFlkXq8oJ9jJDLlB/7rymr751KiQohbvhVA
 EklF4P8zQNtMMhqSPIPlQVo6rdQhawsibpku
 =tVDz
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Al Viro discovered some breakage with the parsing of the
  set_ftrace_filter as well as the removing of function probes.

  This fixes the code with Al's suggestions. I also added a few
  selftests to test the broken cases such that they wont happen
  again"

* tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Add more tests for removing of function probes
  selftests/ftrace: Add some missing glob checks
  selftests/ftrace: Have reset_ftrace_filter handle multiple instances
  selftests/ftrace: Have reset_ftrace_filter handle modules
  tracing: Fix parsing of globs with a wildcard at the beginning
  ftrace: Remove incorrect setting of glob search field
2018-02-09 14:47:09 -08:00
Steven Rostedt (VMware) 0723402141 tracing: Fix parsing of globs with a wildcard at the beginning
Al Viro reported:

    For substring - sure, but what about something like "*a*b" and "a*b"?
    AFAICS, filter_parse_regex() ends up with identical results in both
    cases - MATCH_GLOB and *search = "a*b".  And no way for the caller
    to tell one from another.

Testing this with the following:

 # cd /sys/kernel/tracing
 # echo '*raw*lock' > set_ftrace_filter
 bash: echo: write error: Invalid argument

With this patch:

 # echo '*raw*lock' > set_ftrace_filter
 # cat set_ftrace_filter
_raw_read_trylock
_raw_write_trylock
_raw_read_unlock
_raw_spin_unlock
_raw_write_unlock
_raw_spin_trylock
_raw_spin_lock
_raw_write_lock
_raw_read_lock

Al recommended not setting the search buffer to skip the first '*' unless we
know we are not using MATCH_GLOB. This implements his suggested logic.

Link: http://lkml.kernel.org/r/20180127170748.GF13338@ZenIV.linux.org.uk

Cc: stable@vger.kernel.org
Fixes: 60f1d5e3ba ("ftrace: Support full glob matching")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Suggsted-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-02-08 10:11:47 -05:00
Steven Rostedt (VMware) 7b65865627 ftrace: Remove incorrect setting of glob search field
__unregister_ftrace_function_probe() will incorrectly parse the glob filter
because it resets the search variable that was setup by filter_parse_regex().

Al Viro reported this:

    After that call of filter_parse_regex() we could have func_g.search not
    equal to glob only if glob started with '!' or '*'.  In the former case
    we would've buggered off with -EINVAL (not = 1).  In the latter we
    would've set func_g.search equal to glob + 1, calculated the length of
    that thing in func_g.len and proceeded to reset func_g.search back to
    glob.

    Suppose the glob is e.g. *foo*.  We end up with
	    func_g.type = MATCH_MIDDLE_ONLY;
	    func_g.len = 3;
	    func_g.search = "*foo";
    Feeding that to ftrace_match_record() will not do anything sane - we
    will be looking for names containing "*foo" (->len is ignored for that
    one).

Link: http://lkml.kernel.org/r/20180127031706.GE13338@ZenIV.linux.org.uk

Cc: stable@vger.kernel.org
Fixes: 3ba0092971 ("ftrace: Introduce ftrace_glob structure")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-02-08 10:11:11 -05:00
Song Liu 33ea4b2427 perf/core: Implement the 'perf_uprobe' PMU
This patch adds perf_uprobe support with similar pattern as previous
patch (for kprobe).

Two functions, create_local_trace_uprobe() and
destroy_local_trace_uprobe(), are created so a uprobe can be created
and attached to the file descriptor created by perf_event_open().

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-7-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-06 11:29:28 +01:00
Song Liu e12f03d703 perf/core: Implement the 'perf_kprobe' PMU
A new PMU type, perf_kprobe is added. Based on attr from perf_event_open(),
perf_kprobe creates a kprobe (or kretprobe) for the perf_event. This
kprobe is private to this perf_event, and thus not added to global
lists, and not available in tracefs.

Two functions, create_local_trace_kprobe() and
destroy_local_trace_kprobe()  are added to created and destroy these
local trace_kprobe.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-6-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-06 11:29:26 +01:00
Linus Torvalds 27529c891b Mostly clean ups and small fixes
There's not much changes for the tracing system this release.
 Mostly small clean ups and fixes.
 
 The biggest change is to how bprintf works. bprintf is used by
 trace_printk() to just save the format and args of a printf call,
 and the formatting is done when the trace buffer is read. This is
 done to keep the formatting out of the fast path (this was recommended
 by you). The issue is when arguments are de-referenced.
 
 If a pointer is saved, and the format has something like "%*pbl",
 when the buffer is read, it will de-reference the argument then.
 The problem is if the data no longer exists. This can cause the
 kernel to oops.
 
 The fix for this was to make these de-reference pointes do
 the formatting at the time it is called (the fast path), as
 this guarantees that the data exists (and doesn't change later)
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlpzUWIUHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUk6FQwAqvrOE8AO9cbwB0bxm82aZj7UyYkG
 D9w4goPiykcNR31wxvM2jhrQn6uqG04g2YFCZntZvZMmGFyu6y/tDxGNGe0cHmVR
 1dZkFcst6IAHybY70cIkAcNNJXFFsccTaVcuniidWYwq2K3z2eqK5s3YfA+ZMr0q
 nfUvv0cIgdGTduM4SuoKr0ewxb779I0tHhQXUnMTeLOWG3HQhOh5LcjdBk/N4pTj
 axfXIlx8lkHSPOvvUmpJ/R51v7HzfidibEnUrrx46ng3DV81hFdEhwbVl+GO44fP
 9Wq7vRCvTThvTZVCg8gaYsuo3+CPISmlkpdq373bCqnKuGynGmXzkFNzXjDHl8pL
 GPbji/Gu9kSMZaZoBihleaX4G4UW386nqDC2YlLTe4rx6f8phYLxMOC2/8nZ+A3L
 JKB4PTWKUSSNCfaPgiT6dv/CeaXalcYtgVJ2xM2jFhoOEyM5jwb0f6tdvXsuj5Fn
 ZlFNTuKWPn0siQIng7EZan3LmIFkukM5sfVF
 =bmm/
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "There's not much changes for the tracing system this release. Mostly
  small clean ups and fixes.

  The biggest change is to how bprintf works. bprintf is used by
  trace_printk() to just save the format and args of a printf call, and
  the formatting is done when the trace buffer is read. This is done to
  keep the formatting out of the fast path (this was recommended by
  you). The issue is when arguments are de-referenced.

  If a pointer is saved, and the format has something like "%*pbl", when
  the buffer is read, it will de-reference the argument then. The
  problem is if the data no longer exists. This can cause the kernel to
  oops.

  The fix for this was to make these de-reference pointes do the
  formatting at the time it is called (the fast path), as this
  guarantees that the data exists (and doesn't change later)"

* tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  vsprintf: Do not have bprintf dereference pointers
  ftrace: Mark function tracer test functions noinline/noclone
  trace_uprobe: Display correct offset in uprobe_events
  tracing: Make sure the parsed string always terminates with '\0'
  tracing: Clear parser->idx if only spaces are read
  tracing: Detect the string nul character when parsing user input string
2018-02-01 13:15:23 -08:00
Linus Torvalds b2fe5fa686 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Significantly shrink the core networking routing structures. Result
    of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf

 2) Add netdevsim driver for testing various offloads, from Jakub
    Kicinski.

 3) Support cross-chip FDB operations in DSA, from Vivien Didelot.

 4) Add a 2nd listener hash table for TCP, similar to what was done for
    UDP. From Martin KaFai Lau.

 5) Add eBPF based queue selection to tun, from Jason Wang.

 6) Lockless qdisc support, from John Fastabend.

 7) SCTP stream interleave support, from Xin Long.

 8) Smoother TCP receive autotuning, from Eric Dumazet.

 9) Lots of erspan tunneling enhancements, from William Tu.

10) Add true function call support to BPF, from Alexei Starovoitov.

11) Add explicit support for GRO HW offloading, from Michael Chan.

12) Support extack generation in more netlink subsystems. From Alexander
    Aring, Quentin Monnet, and Jakub Kicinski.

13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From
    Russell King.

14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso.

15) Many improvements and simplifications to the NFP driver bpf JIT,
    from Jakub Kicinski.

16) Support for ipv6 non-equal cost multipath routing, from Ido
    Schimmel.

17) Add resource abstration to devlink, from Arkadi Sharshevsky.

18) Packet scheduler classifier shared filter block support, from Jiri
    Pirko.

19) Avoid locking in act_csum, from Davide Caratti.

20) devinet_ioctl() simplifications from Al viro.

21) More TCP bpf improvements from Lawrence Brakmo.

22) Add support for onlink ipv6 route flag, similar to ipv4, from David
    Ahern.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits)
  tls: Add support for encryption using async offload accelerator
  ip6mr: fix stale iterator
  net/sched: kconfig: Remove blank help texts
  openvswitch: meter: Use 64-bit arithmetic instead of 32-bit
  tcp_nv: fix potential integer overflow in tcpnv_acked
  r8169: fix RTL8168EP take too long to complete driver initialization.
  qmi_wwan: Add support for Quectel EP06
  rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK
  ipmr: Fix ptrdiff_t print formatting
  ibmvnic: Wait for device response when changing MAC
  qlcnic: fix deadlock bug
  tcp: release sk_frag.page in tcp_disconnect
  ipv4: Get the address of interface correctly.
  net_sched: gen_estimator: fix lockdep splat
  net: macb: Handle HRESP error
  net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring
  ipv6: addrconf: break critical section in addrconf_verify_rtnl()
  ipv6: change route cache aging logic
  i40e/i40evf: Update DESC_NEEDED value to reflect larger value
  bnxt_en: cleanup DIM work on device shutdown
  ...
2018-01-31 14:31:10 -08:00
Linus Torvalds 168fe32a07 Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull poll annotations from Al Viro:
 "This introduces a __bitwise type for POLL### bitmap, and propagates
  the annotations through the tree. Most of that stuff is as simple as
  'make ->poll() instances return __poll_t and do the same to local
  variables used to hold the future return value'.

  Some of the obvious brainos found in process are fixed (e.g. POLLIN
  misspelled as POLL_IN). At that point the amount of sparse warnings is
  low and most of them are for genuine bugs - e.g. ->poll() instance
  deciding to return -EINVAL instead of a bitmap. I hadn't touched those
  in this series - it's large enough as it is.

  Another problem it has caught was eventpoll() ABI mess; select.c and
  eventpoll.c assumed that corresponding POLL### and EPOLL### were
  equal. That's true for some, but not all of them - EPOLL### are
  arch-independent, but POLL### are not.

  The last commit in this series separates userland POLL### values from
  the (now arch-independent) kernel-side ones, converting between them
  in the few places where they are copied to/from userland. AFAICS, this
  is the least disruptive fix preserving poll(2) ABI and making epoll()
  work on all architectures.

  As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
  it will trigger only on what would've triggered EPOLLWRBAND on other
  architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
  at all on sparc. With this patch they should work consistently on all
  architectures"

* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  make kernel-side POLL... arch-independent
  eventpoll: no need to mask the result of epi_item_poll() again
  eventpoll: constify struct epoll_event pointers
  debugging printk in sg_poll() uses %x to print POLL... bitmap
  annotate poll(2) guts
  9p: untangle ->poll() mess
  ->si_band gets POLL... bitmap stored into a user-visible long field
  ring_buffer_poll_wait() return value used as return value of ->poll()
  the rest of drivers/*: annotate ->poll() instances
  media: annotate ->poll() instances
  fs: annotate ->poll() instances
  ipc, kernel, mm: annotate ->poll() instances
  net: annotate ->poll() instances
  apparmor: annotate ->poll() instances
  tomoyo: annotate ->poll() instances
  sound: annotate ->poll() instances
  acpi: annotate ->poll() instances
  crypto: annotate ->poll() instances
  block: annotate ->poll() instances
  x86: annotate ->poll() instances
  ...
2018-01-30 17:58:07 -08:00
Linus Torvalds d772794637 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this cycle were:

   - Updates to use cond_resched() instead of cond_resched_rcu_qs()
     where feasible (currently everywhere except in kernel/rcu and in
     kernel/torture.c). Also a couple of fixes to avoid sending IPIs to
     offline CPUs.

   - Updates to simplify RCU's dyntick-idle handling.

   - Updates to remove almost all uses of smp_read_barrier_depends() and
     read_barrier_depends().

   - Torture-test updates.

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
  torture: Save a line in stutter_wait(): while -> for
  torture: Eliminate torture_runnable and perf_runnable
  torture: Make stutter less vulnerable to compilers and races
  locking/locktorture: Fix num reader/writer corner cases
  locking/locktorture: Fix rwsem reader_delay
  torture: Place all torture-test modules in one MAINTAINERS group
  rcutorture/kvm-build.sh: Skip build directory check
  rcutorture: Simplify functions.sh include path
  rcutorture: Simplify logging
  rcutorture/kvm-recheck-*: Improve result directory readability check
  rcutorture/kvm.sh: Support execution from any directory
  rcutorture/kvm.sh: Use consistent help text for --qemu-args
  rcutorture/kvm.sh: Remove unused variable, `alldone`
  rcutorture: Remove unused script, config2frag.sh
  rcutorture/configinit: Fix build directory error message
  rcutorture: Preempt RCU-preempt readers more vigorously
  torture: Reduce #ifdefs for preempt_schedule()
  rcu: Remove have_rcu_nocb_mask from tree_plugin.h
  rcu: Add comment giving debug strategy for double call_rcu()
  tracing, rcu: Hide trace event rcu_nocb_wake when not used
  ...
2018-01-30 10:15:30 -08:00
David S. Miller 955bd1d216 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-24 23:44:15 -05:00
Andi Kleen dd3dad0d71 ftrace: Mark function tracer test functions noinline/noclone
The ftrace function tracer self tests calls some functions to verify
the get traced. This relies on them not being inlined. Previously
this was ensured by putting them into another file, but with LTO
the compiler can inline across files, which makes the tests fail.

Mark these functions as noinline and noclone.

Link: http://lkml.kernel.org/r/20171221233732.31896-1-andi@firstfloor.org

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:29 -05:00
Ravi Bangoria 0e4d819d08 trace_uprobe: Display correct offset in uprobe_events
Recently, how the pointers being printed with %p has been changed
by commit ad67b74d24 ("printk: hash addresses printed with %p").
This is causing a regression while showing offset in the
uprobe_events file. Instead of %p, use %px to display offset.

Before patch:

  # perf probe -vv -x /tmp/a.out main
  Opening /sys/kernel/debug/tracing//uprobe_events write=1
  Writing event: p:probe_a/main /tmp/a.out:0x58c

  # cat /sys/kernel/debug/tracing/uprobe_events
  p:probe_a/main /tmp/a.out:0x0000000049a0f352

After patch:

  # cat /sys/kernel/debug/tracing/uprobe_events
  p:probe_a/main /tmp/a.out:0x000000000000058c

Link: http://lkml.kernel.org/r/20180106054246.15375-1-ravi.bangoria@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:29 -05:00
Changbin Du f4d0706cde tracing: Make sure the parsed string always terminates with '\0'
Always mark the parsed string with a terminated nul '\0' character. This removes
the need for the users to have to append the '\0' before using the parsed string.

Link: http://lkml.kernel.org/r/1516093350-12045-4-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:28 -05:00
Changbin Du 76638d9650 tracing: Clear parser->idx if only spaces are read
If only spaces were read while parsing the next string, then parser->idx should be
cleared in order to make trace_parser_loaded() return false.

Link: http://lkml.kernel.org/r/1516093350-12045-3-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:28 -05:00
Changbin Du 921a7acd85 tracing: Detect the string nul character when parsing user input string
User space can pass in a C nul character '\0' along with its input. The
function trace_get_user() will try to process it as a normal character,
and that will fail to parse.

open("/sys/kernel/debug/tracing//set_ftrace_pid", O_WRONLY|O_TRUNC) = 3
write(3, " \0", 2)                      = -1 EINVAL (Invalid argument)

while parse can handle spaces, so below works.

$ echo "" > set_ftrace_pid
$ echo " " > set_ftrace_pid
$ echo -n " " > set_ftrace_pid

Have the parser stop on '\0' and cease any further parsing. Only process
the characters up to the nul '\0' character and do not process it.

Link: http://lkml.kernel.org/r/1516093350-12045-2-git-send-email-changbin.du@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:27 -05:00
Steven Rostedt (VMware) 2ee5b92a25 tracing: Update stack trace skipping for ORC unwinder
With the addition of ORC unwinder and FRAME POINTER unwinder, the stack
trace skipping requirements have changed.

I went through the tracing stack trace dumps with ORC and with frame
pointers and recalculated the proper values.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:57:00 -05:00
Steven Rostedt (VMware) 6be7fa3c74 ftrace, orc, x86: Handle ftrace dynamically allocated trampolines
The function tracer can create a dynamically allocated trampoline that is
called by the function mcount or fentry hook that is used to call the
function callback that is registered. The problem is that the orc undwinder
will bail if it encounters one of these trampolines. This breaks the stack
trace of function callbacks, which include the stack tracer and setting the
stack trace for individual functions.

Since these dynamic trampolines are basically copies of the static ftrace
trampolines defined in ftrace_*.S, we do not need to create new orc entries
for the dynamic trampolines. Finding the return address on the stack will be
identical as the functions that were copied to create the dynamic
trampolines. When encountering a ftrace dynamic trampoline, we can just use
the orc entry of the ftrace static function that was copied for that
trampoline.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-23 15:56:55 -05:00
David S. Miller ea9722e265 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2018-01-19

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) bpf array map HW offload, from Jakub.

2) support for bpf_get_next_key() for LPM map, from Yonghong.

3) test_verifier now runs loaded programs, from Alexei.

4) xdp cpumap monitoring, from Jesper.

5) variety of tests, cleanups and small x64 JIT optimization, from Daniel.

6) user space can now retrieve HW JITed program, from Jiong.

Note there is a minor conflict between Russell's arm32 JIT fixes
and removal of bpf_jit_enable variable by Daniel which should
be resolved by keeping Russell's comment and removing that variable.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-20 22:03:46 -05:00
David S. Miller 8565d26bcb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The BPF verifier conflict was some minor contextual issue.

The TUN conflict was less trivial.  Cong Wang fixed a memory leak of
tfile->tx_array in 'net'.  This is an skb_array.  But meanwhile in
net-next tun changed tfile->tx_arry into tfile->tx_ring which is a
ptr_ring.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 22:59:33 -05:00
Steven Rostedt (VMware) 1ebe1eaf2f tracing: Fix converting enum's from the map in trace_event_eval_update()
Since enums do not get converted by the TRACE_EVENT macro into their values,
the event format displaces the enum name and not the value. This breaks
tools like perf and trace-cmd that need to interpret the raw binary data. To
solve this, an enum map was created to convert these enums into their actual
numbers on boot up. This is done by TRACE_EVENTS() adding a
TRACE_DEFINE_ENUM() macro.

Some enums were not being converted. This was caused by an optization that
had a bug in it.

All calls get checked against this enum map to see if it should be converted
or not, and it compares the call's system to the system that the enum map
was created under. If they match, then they call is processed.

To cut down on the number of iterations needed to find the maps with a
matching system, since calls and maps are grouped by system, when a match is
made, the index into the map array is saved, so that the next call, if it
belongs to the same system as the previous call, could start right at that
array index and not have to scan all the previous arrays.

The problem was, the saved index was used as the variable to know if this is
a call in a new system or not. If the index was zero, it was assumed that
the call is in a new system and would keep incrementing the saved index
until it found a matching system. The issue arises when the first matching
system was at index zero. The next map, if it belonged to the same system,
would then think it was the first match and increment the index to one. If
the next call belong to the same system, it would begin its search of the
maps off by one, and miss the first enum that should be converted. This left
a single enum not converted properly.

Also add a comment to describe exactly what that index was for. It took me a
bit too long to figure out what I was thinking when debugging this issue.

Link: http://lkml.kernel.org/r/717BE572-2070-4C1E-9902-9F2E0FEDA4F8@oracle.com

Cc: stable@vger.kernel.org
Fixes: 0c564a538a ("tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values")
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Teste-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-18 15:53:10 -05:00
Steven Rostedt (VMware) 0164e0d7e8 ring-buffer: Fix duplicate results in mapping context to bits in recursive lock
In bringing back the context checks, the code checks first if its normal
(non-interrupt) context, and then for NMI then IRQ then softirq. The final
check is redundant. Since the if branch is only hit if the context is one of
NMI, IRQ, or SOFTIRQ, if it's not NMI or IRQ there's no reason to check if
it is SOFTIRQ. The current code returns the same result even if its not a
SOFTIRQ. Which is confusing.

  pc & SOFTIRQ_OFFSET ? 2 : RB_CTX_SOFTIRQ

Is redundant as RB_CTX_SOFTIRQ *is* 2!

Fixes: a0e3a18f4b ("ring-buffer: Bring back context level recursive checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-18 15:45:48 -05:00
Yonghong Song eefa864a81 bpf: change fake_ip for bpf_trace_printk helper
Currently, for bpf_trace_printk helper, fake ip address 0x1
is used with comments saying that fake ip will not be printed.
This is indeed true for 4.12 and earlier version, but for
4.13 and later version, the ip address will be printed if
it cannot be resolved with kallsym. Running samples/bpf/tracex5
program and you will have the following in the debugfs
trace_pipe output:
  ...
  <...>-1819  [003] ....   443.497877: 0x00000001: mmap
  <...>-1819  [003] ....   443.498289: 0x00000001: syscall=102 (one of get/set uid/pid/gid)
  ...

The kernel commit changed this behavior is:
  commit feaf1283d1
  Author: Steven Rostedt (VMware) <rostedt@goodmis.org>
  Date:   Thu Jun 22 17:04:55 2017 -0400

      tracing: Show address when function names are not found
  ...

This patch changed the comment and also altered the fake ip
address to 0x0 as users may think 0x1 has some special meaning
while it doesn't. The new output:
  ...
  <...>-1799  [002] ....    25.953576: 0: mmap
  <...>-1799  [002] ....    25.953865: 0: read(fd=0, buf=00000000053936b5, size=512)
  ...

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-18 01:51:42 +01:00
David S. Miller c02b3741eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes all over.

The mini-qdisc bits were a little bit tricky, however.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 00:10:42 -05:00
Randy Dunlap 68e76e034b tracing: Prevent PROFILE_ALL_BRANCHES when FORTIFY_SOURCE=y
I regularly get 50 MB - 60 MB files during kernel randconfig builds.
These large files mostly contain (many repeats of; e.g., 124,594):

In file included from ../include/linux/string.h:6:0,
                 from ../include/linux/uuid.h:20,
                 from ../include/linux/mod_devicetable.h:13,
                 from ../scripts/mod/devicetable-offsets.c:3:
../include/linux/compiler.h:64:4: warning: '______f' is static but declared in inline function 'strcpy' which is not static [enabled by default]
    ______f = {     \
    ^
../include/linux/compiler.h:56:23: note: in expansion of macro '__trace_if'
                       ^
../include/linux/string.h:425:2: note: in expansion of macro 'if'
  if (p_size == (size_t)-1 && q_size == (size_t)-1)
  ^

This only happens when CONFIG_FORTIFY_SOURCE=y and
CONFIG_PROFILE_ALL_BRANCHES=y, so prevent PROFILE_ALL_BRANCHES if
FORTIFY_SOURCE=y.

Link: http://lkml.kernel.org/r/9199446b-a141-c0c3-9678-a3f9107f2750@infradead.org

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-15 14:15:31 -05:00
Steven Rostedt (VMware) a0e3a18f4b ring-buffer: Bring back context level recursive checks
Commit 1a149d7d3f ("ring-buffer: Rewrite trace_recursive_(un)lock() to be
simpler") replaced the context level recursion checks with a simple counter.
This would prevent the ring buffer code from recursively calling itself more
than the max number of contexts that exist (Normal, softirq, irq, nmi). But
this change caused a lockup in a specific case, which was during suspend and
resume using a global clock. Adding a stack dump to see where this occurred,
the issue was in the trace global clock itself:

  trace_buffer_lock_reserve+0x1c/0x50
  __trace_graph_entry+0x2d/0x90
  trace_graph_entry+0xe8/0x200
  prepare_ftrace_return+0x69/0xc0
  ftrace_graph_caller+0x78/0xa8
  queued_spin_lock_slowpath+0x5/0x1d0
  trace_clock_global+0xb0/0xc0
  ring_buffer_lock_reserve+0xf9/0x390

The function graph tracer traced queued_spin_lock_slowpath that was called
by trace_clock_global. This pointed out that the trace_clock_global() is not
reentrant, as it takes a spin lock. It depended on the ring buffer recursive
lock from letting that happen.

By removing the context detection and adding just a max number of allowable
recursions, it allowed the trace_clock_global() to be entered again and try
to retake the spinlock it already held, causing a deadlock.

Fixes: 1a149d7d3f ("ring-buffer: Rewrite trace_recursive_(un)lock() to be simpler")
Reported-by: David Weinehall <david.weinehall@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-15 12:28:06 -05:00
Masami Hiramatsu 540adea380 error-injection: Separate error-injection from kprobe
Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.

Some differences has been made:

- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
  ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
  feature. It is automatically enabled if the arch supports
  error injection feature for kprobe or ftrace etc.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:38 -08:00
Masami Hiramatsu 66665ad2f1 tracing/kprobe: bpf: Compare instruction pointer with original one
Compare instruction pointer with original one on the
stack instead using per-cpu bpf_kprobe_override flag.

This patch also consolidates reset_current_kprobe() and
preempt_enable_no_resched() blocks. Those can be done
in one place.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:38 -08:00
Masami Hiramatsu b4da3340ea tracing/kprobe: bpf: Check error injectable event is on function entry
Check whether error injectable event is on function entry or not.
Currently it checks the event is ftrace-based kprobes or not,
but that is wrong. It should check if the event is on the entry
of target function. Since error injection will override a function
to just return with modified return value, that operation must
be done before the target function starts making stackframe.

As a side effect, bpf error injection is no need to depend on
function-tracer. It can work with sw-breakpoint based kprobe
events too.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12 17:33:37 -08:00
Ingo Molnar 475c5ee193 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

- Updates to use cond_resched() instead of cond_resched_rcu_qs()
  where feasible (currently everywhere except in kernel/rcu and
  in kernel/torture.c).  Also a couple of fixes to avoid sending
  IPIs to offline CPUs.

- Updates to simplify RCU's dyntick-idle handling.

- Updates to remove almost all uses of smp_read_barrier_depends()
  and read_barrier_depends().

- Miscellaneous fixes.

- Torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-03 14:14:18 +01:00
David S. Miller 6bb8824732 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/ipv6/ip6_gre.c is a case of parallel adds.

include/trace/events/tcp.h is a little bit more tricky.  The removal
of in-trace-macro ifdefs in 'net' paralleled with moving
show_tcp_state_name and friends over to include/trace/events/sock.h
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-29 15:42:26 -05:00
Steven Rostedt (VMware) 4397f04575 tracing: Fix possible double free on failure of allocating trace buffer
Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@spreadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:27 -05:00
Jing Xia 24f2aaf952 tracing: Fix crash when it fails to alloc ring buffer
Double free of the ring buffer happens when it fails to alloc new
ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured.
The root cause is that the pointer is not set to NULL after the buffer
is freed in allocate_trace_buffers(), and the freeing of the ring
buffer is invoked again later if the pointer is not equal to Null,
as:

instance_mkdir()
    |-allocate_trace_buffers()
        |-allocate_trace_buffer(tr, &tr->trace_buffer...)
	|-allocate_trace_buffer(tr, &tr->max_buffer...)

          // allocate fail(-ENOMEM),first free
          // and the buffer pointer is not set to null
        |-ring_buffer_free(tr->trace_buffer.buffer)

       // out_free_tr
    |-free_trace_buffers()
        |-free_trace_buffer(&tr->trace_buffer);

	      //if trace_buffer is not null, free again
	    |-ring_buffer_free(buf->buffer)
                |-rb_free_cpu_buffer(buffer->buffers[cpu])
                    // ring_buffer_per_cpu is null, and
                    // crash in ring_buffer_per_cpu->pages

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Signed-off-by: Jing Xia <jing.xia@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:16 -05:00
Steven Rostedt (VMware) ae415fa4c5 ring-buffer: Do no reuse reader page if still in use
To free the reader page that is allocated with ring_buffer_alloc_read_page(),
ring_buffer_free_read_page() must be called. For faster performance, this
page can be reused by the ring buffer to avoid having to free and allocate
new pages.

The issue arises when the page is used with a splice pipe into the
networking code. The networking code may up the page counter for the page,
and keep it active while sending it is queued to go to the network. The
incrementing of the page ref does not prevent it from being reused in the
ring buffer, and this can cause the page that is being sent out to the
network to be modified before it is sent by reading new data.

Add a check to the page ref counter, and only reuse the page if it is not
being used anywhere else.

Cc: stable@vger.kernel.org
Fixes: 73a757e631 ("ring-buffer: Return reader page back into existing ring buffer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:09 -05:00
Steven Rostedt (VMware) 6b7e633fe9 tracing: Remove extra zeroing out of the ring buffer page
The ring_buffer_read_page() takes care of zeroing out any extra data in the
page that it returns. There's no need to zero it out again from the
consumer. It was removed from one consumer of this function, but
read_buffers_splice_read() did not remove it, and worse, it contained a
nasty bug because of it.

Cc: stable@vger.kernel.org
Fixes: 2711ca237a ("ring-buffer: Move zeroing out excess in page to ring buffer code")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:20:59 -05:00
Steven Rostedt (VMware) 45d8b80c2a ring-buffer: Mask out the info bits when returning buffer page length
Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.

What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.

Cc: stable@vger.kernel.org
Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:18:10 -05:00
David S. Miller 59436c9ee1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2017-12-18

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Allow arbitrary function calls from one BPF function to another BPF function.
   As of today when writing BPF programs, __always_inline had to be used in
   the BPF C programs for all functions, unnecessarily causing LLVM to inflate
   code size. Handle this more naturally with support for BPF to BPF calls
   such that this __always_inline restriction can be overcome. As a result,
   it allows for better optimized code and finally enables to introduce core
   BPF libraries in the future that can be reused out of different projects.
   x86 and arm64 JIT support was added as well, from Alexei.

2) Add infrastructure for tagging functions as error injectable and allow for
   BPF to return arbitrary error values when BPF is attached via kprobes on
   those. This way of injecting errors generically eases testing and debugging
   without having to recompile or restart the kernel. Tags for opting-in for
   this facility are added with BPF_ALLOW_ERROR_INJECTION(), from Josef.

3) For BPF offload via nfp JIT, add support for bpf_xdp_adjust_head() helper
   call for XDP programs. First part of this work adds handling of BPF
   capabilities included in the firmware, and the later patches add support
   to the nfp verifier part and JIT as well as some small optimizations,
   from Jakub.

4) The bpftool now also gets support for basic cgroup BPF operations such
   as attaching, detaching and listing current BPF programs. As a requirement
   for the attach part, bpftool can now also load object files through
   'bpftool prog load'. This reuses libbpf which we have in the kernel tree
   as well. bpftool-cgroup man page is added along with it, from Roman.

5) Back then commit e87c6bc385 ("bpf: permit multiple bpf attachments for
   a single perf event") added support for attaching multiple BPF programs
   to a single perf event. Given they are configured through perf's ioctl()
   interface, the interface has been extended with a PERF_EVENT_IOC_QUERY_BPF
   command in this work in order to return an array of one or multiple BPF
   prog ids that are currently attached, from Yonghong.

6) Various minor fixes and cleanups to the bpftool's Makefile as well
   as a new 'uninstall' and 'doc-uninstall' target for removing bpftool
   itself or prior installed documentation related to it, from Quentin.

7) Add CONFIG_CGROUP_BPF=y to the BPF kernel selftest config file which is
   required for the test_dev_cgroup test case to run, from Naresh.

8) Fix reporting of XDP prog_flags for nfp driver, from Jakub.

9) Fix libbpf's exit code from the Makefile when libelf was not found in
   the system, also from Jakub.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 10:51:06 -05:00
Josef Bacik 46df3d209d trace: reenable preemption if we modify the ip
Things got moved around between the original bpf_override_return patches
and the final version, and now the ftrace kprobe dispatcher assumes if
you modified the ip that you also enabled preemption.  Make a comment of
this and enable preemption, this fixes the lockdep splat that happened
when using this feature.

Fixes: 9802d86585 ("bpf: add a bpf_override_function helper")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-17 20:47:32 +01:00
Linus Torvalds 7a3c296ae0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Clamp timeouts to INT_MAX in conntrack, from Jay Elliot.

 2) Fix broken UAPI for BPF_PROG_TYPE_PERF_EVENT, from Hendrik
    Brueckner.

 3) Fix locking in ieee80211_sta_tear_down_BA_sessions, from Johannes
    Berg.

 4) Add missing barriers to ptr_ring, from Michael S. Tsirkin.

 5) Don't advertise gigabit in sh_eth when not available, from Thomas
    Petazzoni.

 6) Check network namespace when delivering to netlink taps, from Kevin
    Cernekee.

 7) Kill a race in raw_sendmsg(), from Mohamed Ghannam.

 8) Use correct address in TCP md5 lookups when replying to an incoming
    segment, from Christoph Paasch.

 9) Add schedule points to BPF map alloc/free, from Eric Dumazet.

10) Don't allow silly mtu values to be used in ipv4/ipv6 multicast, also
    from Eric Dumazet.

11) Fix SKB leak in tipc, from Jon Maloy.

12) Disable MAC learning on OVS ports of mlxsw, from Yuval Mintz.

13) SKB leak fix in skB_complete_tx_timestamp(), from Willem de Bruijn.

14) Add some new qmi_wwan device IDs, from Daniele Palmas.

15) Fix static key imbalance in ingress qdisc, from Jiri Pirko.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
  net: qcom/emac: Reduce timeout for mdio read/write
  net: sched: fix static key imbalance in case of ingress/clsact_init error
  net: sched: fix clsact init error path
  ip_gre: fix wrong return value of erspan_rcv
  net: usb: qmi_wwan: add Telit ME910 PID 0x1101 support
  pkt_sched: Remove TC_RED_OFFLOADED from uapi
  net: sched: Move to new offload indication in RED
  net: sched: Add TCA_HW_OFFLOAD
  net: aquantia: Increment driver version
  net: aquantia: Fix typo in ethtool statistics names
  net: aquantia: Update hw counters on hw init
  net: aquantia: Improve link state and statistics check interval callback
  net: aquantia: Fill in multicast counter in ndev stats from hardware
  net: aquantia: Fill ndev stat couters from hardware
  net: aquantia: Extend stat counters to 64bit values
  net: aquantia: Fix hardware DMA stream overload on large MRRS
  net: aquantia: Fix actual speed capabilities reporting
  sock: free skb in skb_complete_tx_timestamp on error
  s390/qeth: update takeover IPs after configuration change
  s390/qeth: lock IP table while applying takeover changes
  ...
2017-12-15 13:08:37 -08:00
Linus Torvalds 0424378781 Various fix ups.
- Comment fixes
  - Build fix
  - Better memory alloction (don't use NR_CPUS)
  - Configuration fix
  - Build warning fix
  - Enhanced callback parameter (to simplify users of trace hooks)
  - Give up on stack tracing when RCU isn't watching (it's a lost cause)
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAlozKm0UHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUmhXwv7BEY923K3Nl3qC6LeYmNyrZ4g1PsD
 nbZ+ZjU3KlMPugGbnJCJbfsS0utUp2Wd9gHT32O4BUf0/Pxjo3utXvkzRQJ3SwHT
 X7QhXROkicAKRFrPxj0BaiLexC+yJR23wGp2YUVHLO4Aa/ptN8BJvH22+eDpsCLc
 f1DWJdvdbyPBUeoHNKevjvccsUYMlnBfe1jhJ9nRWHnq1axGV3bllcd6v4T07LgK
 LO28Krp4/V3tVN9Sq6jBoGTrULf5O1xtuBDVtANeXdha1oMUTYr4TUzTuOQxFgNu
 sCIpUWTKu+PNGmU5bhlryb20C2+PveE4EMK0InVVlqrhYJ/XjXFyRaZYYkM2NAKq
 XmeHVjMfc6Wmrd/nepuaTZvGGrK2kK/pCX/XuQthKKjAU6rO5X+FfGiSGodLPIYB
 1m+QvfX8Re2IJkswm3lS68LKtG7SnjcSB9sY6PhVe6C6oP2ya2O1hthJ+TkrfNbc
 lhE5HzfCJZ9ujSjcQoUGwjrhnIezQX4KnfJZ
 =WdMQ
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Various fix-ups:

   - comment fixes

   - build fix

   - better memory alloction (don't use NR_CPUS)

   - configuration fix

   - build warning fix

   - enhanced callback parameter (to simplify users of trace hooks)

   - give up on stack tracing when RCU isn't watching (it's a lost
     cause)"

* tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have stack trace not record if RCU is not watching
  tracing: Pass export pointer as argument to ->write()
  ring-buffer: Remove unused function __rb_data_page_index()
  tracing: make PREEMPTIRQ_EVENTS depend on TRACING
  tracing: Allocate mask_str buffer dynamically
  tracing: always define trace_{irq,preempt}_{enable_disable}
  tracing: Fix code comments in trace.c
2017-12-14 18:21:33 -08:00
Steven Rostedt (VMware) b00d607bb1 tracing: Have stack trace not record if RCU is not watching
The stack tracer records a stack dump whenever it sees a stack usage that is
more than what it ever saw before. This can happen at any function that is
being traced. If it happens when the CPU is going idle (or other strange
locations), RCU may not be watching, and in this case, the recording of the
stack trace will trigger a warning. There's been lots of efforts to make
hacks to allow stack tracing to proceed even if RCU is not watching, but
this only causes more issues to appear. Simply do not trace a stack if RCU
is not watching. It probably isn't a bad stack anyway.

Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-14 20:48:22 -05:00
Yonghong Song f4e2298e63 bpf/tracing: fix kernel/events/core.c compilation error
Commit f371b304f1 ("bpf/tracing: allow user space to
query prog array on the same tp") introduced a perf
ioctl command to query prog array attached to the
same perf tracepoint. The commit introduced a
compilation error under certain config conditions, e.g.,
  (1). CONFIG_BPF_SYSCALL is not defined, or
  (2). CONFIG_TRACING is defined but neither CONFIG_UPROBE_EVENTS
       nor CONFIG_KPROBE_EVENTS is defined.

Error message:
  kernel/events/core.o: In function `perf_ioctl':
  core.c:(.text+0x98c4): undefined reference to `bpf_event_query_prog_array'

This patch fixed this error by guarding the real definition under
CONFIG_BPF_EVENTS and provided static inline dummy function
if CONFIG_BPF_EVENTS was not defined.
It renamed the function from bpf_event_query_prog_array to
perf_event_query_prog_array and moved the definition from linux/bpf.h
to linux/trace_events.h so the definition is in proximity to
other prog_array related functions.

Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-13 22:44:10 +01:00
Daniel Borkmann 283ca526a9 bpf: fix corruption on concurrent perf_event_output calls
When tracing and networking programs are both attached in the
system and both use event-output helpers that eventually call
into perf_event_output(), then we could end up in a situation
where the tracing attached program runs in user context while
a cls_bpf program is triggered on that same CPU out of softirq
context.

Since both rely on the same per-cpu perf_sample_data, we could
potentially corrupt it. This can only ever happen in a combination
of the two types; all tracing programs use a bpf_prog_active
counter to bail out in case a program is already running on
that CPU out of a different context. XDP and cls_bpf programs
by themselves don't have this issue as they run in the same
context only. Therefore, split both perf_sample_data so they
cannot be accessed from each other.

Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Reported-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:51:12 -08:00
Josef Bacik 9802d86585 bpf: add a bpf_override_function helper
Error injection is sloppy and very ad-hoc.  BPF could fill this niche
perfectly with it's kprobe functionality.  We could make sure errors are
only triggered in specific call chains that we care about with very
specific situations.  Accomplish this with the bpf_override_funciton
helper.  This will modify the probe'd callers return value to the
specified value and set the PC to an override function that simply
returns, bypassing the originally probed function.  This gives us a nice
clean way to implement systematic error injection for all of our code
paths.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:02:34 -08:00
Yonghong Song f371b304f1 bpf/tracing: allow user space to query prog array on the same tp
Commit e87c6bc385 ("bpf: permit multiple bpf attachments
for a single perf event") added support to attach multiple
bpf programs to a single perf event.
Although this provides flexibility, users may want to know
what other bpf programs attached to the same tp interface.
Besides getting visibility for the underlying bpf system,
such information may also help consolidate multiple bpf programs,
understand potential performance issues due to a large array,
and debug (e.g., one bpf program which overwrites return code
may impact subsequent program results).

Commit 2541517c32 ("tracing, perf: Implement BPF programs
attached to kprobes") utilized the existing perf ioctl
interface and added the command PERF_EVENT_IOC_SET_BPF
to attach a bpf program to a tracepoint. This patch adds a new
ioctl command, given a perf event fd, to query the bpf program
array attached to the same perf tracepoint event.

The new uapi ioctl command:
  PERF_EVENT_IOC_QUERY_BPF

The new uapi/linux/perf_event.h structure:
  struct perf_event_query_bpf {
       __u32	ids_len;
       __u32	prog_cnt;
       __u32	ids[0];
  };

User space provides buffer "ids" for kernel to copy to.
When returning from the kernel, the number of available
programs in the array is set in "prog_cnt".

The usage:
  struct perf_event_query_bpf *query =
    malloc(sizeof(*query) + sizeof(u32) * ids_len);
  query.ids_len = ids_len;
  err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query);
  if (err == 0) {
    /* query.prog_cnt is the number of available progs,
     * number of progs in ids: (ids_len == 0) ? 0 : query.prog_cnt
     */
  } else if (errno == ENOSPC) {
    /* query.ids_len number of progs copied,
     * query.prog_cnt is the number of available progs
     */
  } else {
      /* other errors */
  }

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 08:46:40 -08:00
Paul E. McKenney 1dfa55e019 Merge branches 'cond_resched.2017.12.04a', 'dyntick.2017.11.28a', 'fixes.2017.12.11a', 'srbd.2017.12.05a' and 'torture.2017.12.11a' into HEAD
cond_resched.2017.12.04a: Convert cond_resched_rcu_qs() to cond_resched()
dyntick.2017.11.28a: Make RCU dynticks handle interrupts from NMI
fixes.2017.12.11a: Miscellaneous fixes
srbd.2017.12.05a: Remove now-redundant smp_read_barrier_depends()
torture.2017.12.11a: Torture-testing update
2017-12-11 09:21:58 -08:00
Linus Torvalds 236fa078c6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Various TCP control block fixes, including one that crashes with
    SELinux, from David Ahern and Eric Dumazet.

 2) Fix ACK generation in rxrpc, from David Howells.

 3) ipvlan doesn't set the mark properly in the ipv4 route lookup key,
    from Gao Feng.

 4) SIT configuration doesn't take on the frag_off ipv4 field
    configuration properly, fix from Hangbin Liu.

 5) TSO can fail after device down/up on stmmac, fix from Lars Persson.

 6) Various bpftool fixes (mostly in JSON handling) from Quentin Monnet.

 7) Various SKB leak fixes in vhost/tun/tap (mostly observed as
    performance problems). From Wei Xu.

 8) mvpps's TX descriptors were not zero initialized, from Yan Markman.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
  tcp: use IPCB instead of TCP_SKB_CB in inet_exact_dif_match()
  tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()
  rxrpc: Fix the MAINTAINERS record
  rxrpc: Use correct netns source in rxrpc_release_sock()
  liquidio: fix incorrect indentation of assignment statement
  stmmac: reset last TSO segment size after device open
  ipvlan: Add the skb->mark as flow4's member to lookup route
  s390/qeth: build max size GSO skbs on L2 devices
  s390/qeth: fix GSO throughput regression
  s390/qeth: fix thinko in IPv4 multicast address tracking
  tap: free skb if flags error
  tun: free skb in early errors
  vhost: fix skb leak in handle_rx()
  bnxt_en: Fix a variable scoping in bnxt_hwrm_do_send_msg()
  bnxt_en: fix dst/src fid for vxlan encap/decap actions
  bnxt_en: wildcard smac while creating tunnel decap filter
  bnxt_en: Need to unconditionally shut down RoCE in bnxt_shutdown
  phylink: ensure we take the link down when phylink_stop() is called
  sfp: warn about modules requiring address change sequence
  sfp: improve RX_LOS handling
  ...
2017-12-04 11:14:46 -08:00
Paul E. McKenney e31d28b6ab trace: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs().  This
commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
2017-12-04 10:28:58 -08:00
Felipe Balbi a773d41927 tracing: Pass export pointer as argument to ->write()
By passing an export descriptor to the write function, users don't need to
keep a global static pointer and can rely on container_of() to fetch their
own structure.

Link: http://lkml.kernel.org/r/20170602102025.5140-1-felipe.balbi@linux.intel.com

Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:14:30 -05:00
Matthias Kaehlcke c4bfd39d7f ring-buffer: Remove unused function __rb_data_page_index()
This fixes the following warning when building with clang:

kernel/trace/ring_buffer.c:1842:1: error: unused function
    '__rb_data_page_index' [-Werror,-Wunused-function]

Link: http://lkml.kernel.org/r/20170518001415.5223-1-mka@chromium.org

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:04:01 -05:00
Arnd Bergmann 2dde6b0034 tracing: make PREEMPTIRQ_EVENTS depend on TRACING
When CONFIG_TRACING is disabled, the new preemptirq events tracer
produces a build failure:

In file included from kernel/trace/trace_irqsoff.c:17:0:
kernel/trace/trace.h: In function 'trace_test_and_set_recursion':
kernel/trace/trace.h:542:28: error: 'struct task_struct' has no member named 'trace_recursion'

Adding an explicit dependency avoids the broken configuration.

Link: http://lkml.kernel.org/r/20171103104031.270375-1-arnd@arndb.de

Fixes: d59158162e ("tracing: Add support for preempt and irq enable/disable events")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:09 -05:00
Changbin Du 90e406f96f tracing: Allocate mask_str buffer dynamically
The default NR_CPUS can be very large, but actual possible nr_cpu_ids
usually is very small. For my x86 distribution, the NR_CPUS is 8192 and
nr_cpu_ids is 4. About 2 pages are wasted.

Most machines don't have so many CPUs, so define a array with NR_CPUS
just wastes memory. So let's allocate the buffer dynamically when need.

With this change, the mutext tracing_cpumask_update_lock also can be
removed now, which was used to protect mask_str.

Link: http://lkml.kernel.org/r/1512013183-19107-1-git-send-email-changbin.du@intel.com

Fixes: 36dfe9252b ("ftrace: make use of tracing_cpumask")
Cc: stable@vger.kernel.org
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:08 -05:00
Chunyu Hu 5a93bae2c3 tracing: Fix code comments in trace.c
Naming in code comments for tracing_snapshot, tracing_snapshot_alloc
and trace_pid_filter_add_remove_task don't match the real function
names.  And latency_trace has been removed from tracing directory.
Fix them.

Link: http://lkml.kernel.org/r/1508394753-20887-1-git-send-email-chuhu@redhat.com

Fixes: cab5037 ("tracing/ftrace: Enable snapshot function trigger")
Fixes: 886b5b7 ("tracing: remove /debug/tracing/latency_trace")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
[ Replaced /sys/kernel/debug/tracing with /sys/kerne/tracing ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 06:52:07 -05:00
Linus Torvalds 75f64f68af Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A selection of fixes/changes that should make it into this series.
  This contains:

   - NVMe, two merges, containing:
        - pci-e, rdma, and fc fixes
        - Device quirks

   - Fix for a badblocks leak in null_blk

   - bcache fix from Rui Hua for a race condition regression where
     -EINTR was returned to upper layers that didn't expect it.

   - Regression fix for blktrace for a bug introduced in this series.

   - blktrace cleanup for cgroup id.

   - bdi registration error handling.

   - Small series with cleanups for blk-wbt.

   - Various little fixes for typos and the like.

  Nothing earth shattering, most important are the NVMe and bcache fixes"

* 'for-linus' of git://git.kernel.dk/linux-block: (34 commits)
  nvme-pci: fix NULL pointer dereference in nvme_free_host_mem()
  nvme-rdma: fix memory leak during queue allocation
  blktrace: fix trace mutex deadlock
  nvme-rdma: Use mr pool
  nvme-rdma: Check remotely invalidated rkey matches our expected rkey
  nvme-rdma: wait for local invalidation before completing a request
  nvme-rdma: don't complete requests before a send work request has completed
  nvme-rdma: don't suppress send completions
  bcache: check return value of register_shrinker
  bcache: recover data from backing when data is clean
  bcache: Fix building error on MIPS
  bcache: add a comment in journal bucket reading
  nvme-fc: don't use bit masks for set/test_bit() numbers
  blk-wbt: fix comments typo
  blk-wbt: move wbt_clear_stat to common place in wbt_done
  blk-sysfs: remove NULL pointer checking in queue_wb_lat_store
  blk-wbt: remove duplicated setting in wbt_init
  nvme-pci: add quirk for delay before CHK RDY for WDC SN200
  block: remove useless assignment in bio_split
  null_blk: fix dev->badblocks leak
  ...
2017-12-01 08:05:45 -05:00
Yonghong Song c8c088ba0e bpf: set maximum number of attached progs to 64 for a single perf tp
cgropu+bpf prog array has a maximum number of 64 programs.
Let us apply the same limit here.

Fixes: e87c6bc385 ("bpf: permit multiple bpf attachments for a single perf event")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-01 02:56:10 +01:00
Al Viro ecf927000c ring_buffer_poll_wait() return value used as return value of ->poll()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:07:12 -05:00
Al Viro 9dd957485d ipc, kernel, mm: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27 16:20:05 -05:00
Jens Axboe 2967acbb25 blktrace: fix trace mutex deadlock
A previous commit changed the locking around registration/cleanup,
but direct callers of blk_trace_remove() were missed. This means
that if we hit the error path in setup, we will deadlock on
attempting to re-acquire the queue trace mutex.

Fixes: 1f2cac107c ("blktrace: fix unlocked access to init/start-stop/teardown")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-27 12:03:58 -07:00
Paul E. McKenney 844ccdd7dc rcu: Eliminate rcu_irq_enter_disabled()
Now that the irq path uses the rcu_nmi_{enter,exit}() algorithm,
rcu_irq_enter() and rcu_irq_exit() may be used from any context.  There is
thus no need for rcu_irq_enter_disabled() and for the checks using it.
This commit therefore eliminates rcu_irq_enter_disabled().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-11-27 08:42:03 -08:00
Gianluca Borello a60dd35d2e bpf: change bpf_perf_event_output arg5 type to ARG_CONST_SIZE_OR_ZERO
Commit 9fd29c08e5 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
the compiler generates optimized BPF code when checking boundaries of an
argument from C code. A typical example of this optimized code can be
generated using the bpf_perf_event_output helper when operating on variable
memory:

/* len is a generic scalar */
if (len > 0 && len <= 0x7fff)
        bpf_perf_event_output(ctx, &perf_map, 0, buf, len);

110: (79) r5 = *(u64 *)(r10 -40)
111: (bf) r1 = r5
112: (07) r1 += -1
113: (25) if r1 > 0x7ffe goto pc+6
114: (bf) r1 = r6
115: (18) r2 = 0xffff94e5f166c200
117: (b7) r3 = 0
118: (bf) r4 = r7
119: (85) call bpf_perf_event_output#25
R5 min value is negative, either use unsigned or 'var &= const'

With this code, the verifier loses track of the variable.

Replacing arg5 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
avoids this quite common case which leads to usability issues, and the
compiler generates code that the verifier can more easily test:

if (len <= 0x7fff)
        bpf_perf_event_output(ctx, &perf_map, 0, buf, len);

or

bpf_perf_event_output(ctx, &perf_map, 0, buf, len & 0x7fff);

No changes to the bpf_perf_event_output helper are necessary since it can
handle a case where size is 0, and an empty frame is pushed.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello 5c4e120174 bpf: change bpf_probe_read_str arg2 type to ARG_CONST_SIZE_OR_ZERO
Commit 9fd29c08e5 ("bpf: improve verifier ARG_CONST_SIZE_OR_ZERO
semantics") relaxed the treatment of ARG_CONST_SIZE_OR_ZERO due to the way
the compiler generates optimized BPF code when checking boundaries of an
argument from C code. A typical example of this optimized code can be
generated using the bpf_probe_read_str helper when operating on variable
memory:

/* len is a generic scalar */
if (len > 0 && len <= 0x7fff)
        bpf_probe_read_str(p, len, s);

251: (79) r1 = *(u64 *)(r10 -88)
252: (07) r1 += -1
253: (25) if r1 > 0x7ffe goto pc-42
254: (bf) r1 = r7
255: (79) r2 = *(u64 *)(r10 -88)
256: (bf) r8 = r4
257: (85) call bpf_probe_read_str#45
R2 min value is negative, either use unsigned or 'var &= const'

With this code, the verifier loses track of the variable.

Replacing arg2 with ARG_CONST_SIZE_OR_ZERO is thus desirable since it
avoids this quite common case which leads to usability issues, and the
compiler generates code that the verifier can more easily test:

if (len <= 0x7fff)
        bpf_probe_read_str(p, len, s);

or

bpf_probe_read_str(p, len & 0x7fff, s);

No changes to the bpf_probe_read_str helper are necessary since
strncpy_from_unsafe itself immediately returns if the size passed is 0.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Gianluca Borello eb33f2cca4 bpf: remove explicit handling of 0 for arg2 in bpf_probe_read
Commit 9c019e2bc4 ("bpf: change helper bpf_probe_read arg2 type to
ARG_CONST_SIZE_OR_ZERO") changed arg2 type to ARG_CONST_SIZE_OR_ZERO to
simplify writing bpf programs by taking advantage of the new semantics
introduced for ARG_CONST_SIZE_OR_ZERO which allows <!NULL, 0> arguments.

In order to prevent the helper from actually passing a NULL pointer to
probe_kernel_read, which can happen when <NULL, 0> is passed to the helper,
the commit also introduced an explicit check against size == 0.

After the recent introduction of the ARG_PTR_TO_MEM_OR_NULL type,
bpf_probe_read can not receive a pair of <NULL, 0> arguments anymore, thus
the check is not needed anymore and can be removed, since probe_kernel_read
can correctly handle a <!NULL, 0> call. This also fixes the semantics of
the helper before it gets officially released and bpf programs start
relying on this check.

Fixes: 9c019e2bc4 ("bpf: change helper bpf_probe_read arg2 type to ARG_CONST_SIZE_OR_ZERO")
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-22 21:40:54 +01:00
Marcos Paulo de Souza 1690102de5 blktrace: Use blk_trace_bio_get_cgid inside blk_add_trace_bio
We always pass in blk_trace_bio_get_cgid(q, bio) to blk_add_trace_bio().
Since both are readily available in the function already, kill the
argument.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>

Rewrote commit message.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-19 12:37:26 -07:00
Linus Torvalds 2dcd9c71c1 Tracing updates for 4.15:
- Now allow module init functions to be traced
 
  - Clean up some unused or not used by config events (saves space)
 
  - Clean up of trace histogram code
 
  - Add support for preempt and interrupt enabled/disable events
 
  - Other various clean ups
 -----BEGIN PGP SIGNATURE-----
 
 iQHIBAABCgAyFiEEPm6V/WuN2kyArTUe1a05Y9njSUkFAloPGgkUHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQ1a05Y9njSUmfaAwAjge5FWBCBQeby8tVuw4RGAorRgl5
 IFuijFSygcKRMhQFP6B+haHsezeCbNaBBtIncXhoJGDC5XuhUhr9foYf1SChEmYp
 tCOK2o71FgZ8yG539IYCVjG9cJZxPLM0OI7RQ8hcMETAr+eiXPXxHrmrm9kdBtYM
 ZAQERvqI5yu2HWIb87KBc38H0rgYrOJKZt9Rx20as/aqAME7hFvYErFlcnxdmHo+
 LmovJOQBCTicNJ4TXJc418JaUWi9cm/A3uhW3o5aLMoRAxCc/8FD+dq2rg4qlHDH
 tOtK6pwIPHfqRZ3nMLXXWhaa+w+swsxBOnegkvgP2xCyibKjFgh9kzcpaj41w3x1
 0FCfvS7flx9ob//fAB8kxLvJyY5p3Qp3xdvj0+gp2qa3Ga5lSqcMzS419TLY1Yfa
 Jpi2oAagDqP94m0EjAGTkhZMOrsFIDr49g3h7nqz3T3Z54luyXniDoYoO11d+dUF
 vCUiIJz/PsQIE3NVViZiaRtcLVXneLHISmnz
 =h3F2
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from

 - allow module init functions to be traced

 - clean up some unused or not used by config events (saves space)

 - clean up of trace histogram code

 - add support for preempt and interrupt enabled/disable events

 - other various clean ups

* tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits)
  tracing, thermal: Hide cpu cooling trace events when not in use
  tracing, thermal: Hide devfreq trace events when not in use
  ftrace: Kill FTRACE_OPS_FL_PER_CPU
  perf/ftrace: Small cleanup
  perf/ftrace: Fix function trace events
  perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function")
  tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_on
  tracing, memcg, vmscan: Hide trace events when not in use
  tracing/xen: Hide events that are not used when X86_PAE is not defined
  tracing: mark trace_test_buffer as __maybe_unused
  printk: Remove superfluous memory barriers from printk_safe
  ftrace: Clear hashes of stale ips of init memory
  tracing: Add support for preempt and irq enable/disable events
  tracing: Prepare to add preempt and irq trace events
  ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions
  ftrace: Add freeing algorithm to free ftrace_mod_maps
  ftrace: Save module init functions kallsyms symbols for tracing
  ftrace: Allow module init functions to be traced
  ftrace: Add a ftrace_free_mem() function for modules to use
  tracing: Reimplement log2
  ...
2017-11-17 14:58:01 -08:00
Linus Torvalds 7c225c69f8 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...
2017-11-15 19:42:40 -08:00
Levin, Alexander (Sasha Levin) 4950276672 kmemcheck: remove annotations
Patch series "kmemcheck: kill kmemcheck", v2.

As discussed at LSF/MM, kill kmemcheck.

KASan is a replacement that is able to work without the limitation of
kmemcheck (single CPU, slow).  KASan is already upstream.

We are also not aware of any users of kmemcheck (or users who don't
consider KASan as a suitable replacement).

The only objection was that since KASAN wasn't supported by all GCC
versions provided by distros at that time we should hold off for 2
years, and try again.

Now that 2 years have passed, and all distros provide gcc that supports
KASAN, kill kmemcheck again for the very same reasons.

This patch (of 4):

Remove kmemcheck annotations, and calls to kmemcheck from the kernel.

[alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs]
  Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com
Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Linus Torvalds 5bbcc0f595 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Maintain the TCP retransmit queue using an rbtree, with 1GB
      windows at 100Gb this really has become necessary. From Eric
      Dumazet.

   2) Multi-program support for cgroup+bpf, from Alexei Starovoitov.

   3) Perform broadcast flooding in hardware in mv88e6xxx, from Andrew
      Lunn.

   4) Add meter action support to openvswitch, from Andy Zhou.

   5) Add a data meta pointer for BPF accessible packets, from Daniel
      Borkmann.

   6) Namespace-ify almost all TCP sysctl knobs, from Eric Dumazet.

   7) Turn on Broadcom Tags in b53 driver, from Florian Fainelli.

   8) More work to move the RTNL mutex down, from Florian Westphal.

   9) Add 'bpftool' utility, to help with bpf program introspection.
      From Jakub Kicinski.

  10) Add new 'cpumap' type for XDP_REDIRECT action, from Jesper
      Dangaard Brouer.

  11) Support 'blocks' of transformations in the packet scheduler which
      can span multiple network devices, from Jiri Pirko.

  12) TC flower offload support in cxgb4, from Kumar Sanghvi.

  13) Priority based stream scheduler for SCTP, from Marcelo Ricardo
      Leitner.

  14) Thunderbolt networking driver, from Amir Levy and Mika Westerberg.

  15) Add RED qdisc offloadability, and use it in mlxsw driver. From
      Nogah Frankel.

  16) eBPF based device controller for cgroup v2, from Roman Gushchin.

  17) Add some fundamental tracepoints for TCP, from Song Liu.

  18) Remove garbage collection from ipv6 route layer, this is a
      significant accomplishment. From Wei Wang.

  19) Add multicast route offload support to mlxsw, from Yotam Gigi"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2177 commits)
  tcp: highest_sack fix
  geneve: fix fill_info when link down
  bpf: fix lockdep splat
  net: cdc_ncm: GetNtbFormat endian fix
  openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_start
  netem: remove unnecessary 64 bit modulus
  netem: use 64 bit divide by rate
  tcp: Namespace-ify sysctl_tcp_default_congestion_control
  net: Protect iterations over net::fib_notifier_ops in fib_seq_sum()
  ipv6: set all.accept_dad to 0 by default
  uapi: fix linux/tls.h userspace compilation error
  usbnet: ipheth: prevent TX queue timeouts when device not ready
  vhost_net: conditionally enable tx polling
  uapi: fix linux/rxrpc.h userspace compilation errors
  net: stmmac: fix LPI transitioning for dwmac4
  atm: horizon: Fix irq release error
  net-sysfs: trigger netlink notification on ifalias change via sysfs
  openvswitch: Using kfree_rcu() to simplify the code
  openvswitch: Make local function ovs_nsh_key_attr_size() static
  openvswitch: Fix return value check in ovs_meter_cmd_features()
  ...
2017-11-15 11:56:19 -08:00
Linus Torvalds 9682b3dea2 Merge branch 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual rocket-science from trivial tree for 4.15"

* 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  MAINTAINERS: relinquish kconfig
  MAINTAINERS: Update my email address
  treewide: Fix typos in Kconfig
  kfifo: Fix comments
  init/Kconfig: Fix module signing document location
  misc: ibmasm: Return error on error path
  HID: logitech-hidpp: fix mistake in printk, "feeback" -> "feedback"
  MAINTAINERS: Correct path to uDraw PS3 driver
  tracing: Fix doc mistakes in trace sample
  tracing: Kconfig text fixes for CONFIG_HWLAT_TRACER
  MIPS: Alchemy: Remove reverted CONFIG_NETLINK_MMAP from db1xxx_defconfig
  mm/huge_memory.c: fixup grammar in comment
  lib/xz: Add fall-through comments to a switch statement
2017-11-15 10:14:11 -08:00
Linus Torvalds e2c5923c34 Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block
Pull core block layer updates from Jens Axboe:
 "This is the main pull request for block storage for 4.15-rc1.

  Nothing out of the ordinary in here, and no API changes or anything
  like that. Just various new features for drivers, core changes, etc.
  In particular, this pull request contains:

   - A patch series from Bart, closing the whole on blk/scsi-mq queue
     quescing.

   - A series from Christoph, building towards hidden gendisks (for
     multipath) and ability to move bio chains around.

   - NVMe
        - Support for native multipath for NVMe (Christoph).
        - Userspace notifications for AENs (Keith).
        - Command side-effects support (Keith).
        - SGL support (Chaitanya Kulkarni)
        - FC fixes and improvements (James Smart)
        - Lots of fixes and tweaks (Various)

   - bcache
        - New maintainer (Michael Lyle)
        - Writeback control improvements (Michael)
        - Various fixes (Coly, Elena, Eric, Liang, et al)

   - lightnvm updates, mostly centered around the pblk interface
     (Javier, Hans, and Rakesh).

   - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)

   - Writeback series that fix the much discussed hundreds of millions
     of sync-all units. This goes all the way, as discussed previously
     (me).

   - Fix for missing wakeup on writeback timer adjustments (Yafang
     Shao).

   - Fix laptop mode on blk-mq (me).

   - {mq,name} tupple lookup for IO schedulers, allowing us to have
     alias names. This means you can use 'deadline' on both !mq and on
     mq (where it's called mq-deadline). (me).

   - blktrace race fix, oopsing on sg load (me).

   - blk-mq optimizations (me).

   - Obscure waitqueue race fix for kyber (Omar).

   - NBD fixes (Josef).

   - Disable writeback throttling by default on bfq, like we do on cfq
     (Luca Miccio).

   - Series from Ming that enable us to treat flush requests on blk-mq
     like any other request. This is a really nice cleanup.

   - Series from Ming that improves merging on blk-mq with schedulers,
     getting us closer to flipping the switch on scsi-mq again.

   - BFQ updates (Paolo).

   - blk-mq atomic flags memory ordering fixes (Peter Z).

   - Loop cgroup support (Shaohua).

   - Lots of minor fixes from lots of different folks, both for core and
     driver code"

* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
  nvme: fix visibility of "uuid" ns attribute
  blk-mq: fixup some comment typos and lengths
  ide: ide-atapi: fix compile error with defining macro DEBUG
  blk-mq: improve tag waiting setup for non-shared tags
  brd: remove unused brd_mutex
  blk-mq: only run the hardware queue if IO is pending
  block: avoid null pointer dereference on null disk
  fs: guard_bio_eod() needs to consider partitions
  xtensa/simdisk: fix compile error
  nvme: expose subsys attribute to sysfs
  nvme: create 'slaves' and 'holders' entries for hidden controllers
  block: create 'slaves' and 'holders' entries for hidden gendisks
  nvme: also expose the namespace identification sysfs files for mpath nodes
  nvme: implement multipath access to nvme subsystems
  nvme: track shared namespaces
  nvme: introduce a nvme_ns_ids structure
  nvme: track subsystems
  block, nvme: Introduce blk_mq_req_flags_t
  block, scsi: Make SCSI quiesce and resume work reliably
  block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
  ...
2017-11-14 15:32:19 -08:00
Yonghong Song 9c019e2bc4 bpf: change helper bpf_probe_read arg2 type to ARG_CONST_SIZE_OR_ZERO
The helper bpf_probe_read arg2 type is changed
from ARG_CONST_SIZE to ARG_CONST_SIZE_OR_ZERO to permit
size-0 buffer. Together with newer ARG_CONST_SIZE_OR_ZERO
semantics which allows non-NULL buffer with size 0,
this allows simpler bpf programs with verifier acceptance.
The previous commit which changes ARG_CONST_SIZE_OR_ZERO semantics
has details on examples.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14 16:20:03 +09:00
Linus Torvalds 3e2014637c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main updates in this cycle were:

   - Group balancing enhancements and cleanups (Brendan Jackman)

   - Move CPU isolation related functionality into its separate
     kernel/sched/isolation.c file, with related 'housekeeping_*()'
     namespace and nomenclature et al. (Frederic Weisbecker)

   - Improve the interactive/cpu-intense fairness calculation (Josef
     Bacik)

   - Improve the PELT code and related cleanups (Peter Zijlstra)

   - Improve the logic of pick_next_task_fair() (Uladzislau Rezki)

   - Improve the RT IPI based balancing logic (Steven Rostedt)

   - Various micro-optimizations:

   - better !CONFIG_SCHED_DEBUG optimizations (Patrick Bellasi)

   - better idle loop (Cheng Jian)

   - ... plus misc fixes, cleanups and updates"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  sched/core: Optimize sched_feat() for !CONFIG_SCHED_DEBUG builds
  sched/sysctl: Fix attributes of some extern declarations
  sched/isolation: Document isolcpus= boot parameter flags, mark it deprecated
  sched/isolation: Add basic isolcpus flags
  sched/isolation: Move isolcpus= handling to the housekeeping code
  sched/isolation: Handle the nohz_full= parameter
  sched/isolation: Introduce housekeeping flags
  sched/isolation: Split out new CONFIG_CPU_ISOLATION=y config from CONFIG_NO_HZ_FULL
  sched/isolation: Rename is_housekeeping_cpu() to housekeeping_cpu()
  sched/isolation: Use its own static key
  sched/isolation: Make the housekeeping cpumask private
  sched/isolation: Provide a dynamic off-case to housekeeping_any_cpu()
  sched/isolation, watchdog: Use housekeeping_cpumask() instead of ad-hoc version
  sched/isolation: Move housekeeping related code to its own file
  sched/idle: Micro-optimize the idle loop
  sched/isolcpus: Fix "isolcpus=" boot parameter handling when !CONFIG_CPUMASK_OFFSTACK
  x86/tsc: Append the 'tsc=' description for the 'tsc=unstable' boot parameter
  sched/rt: Simplify the IPI based RT balancing logic
  block/ioprio: Use a helper to check for RT prio
  sched/rt: Add a helper to test for a RT task
  ...
2017-11-13 13:37:52 -08:00
Linus Torvalds 31486372a1 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main changes in this cycle were:

  Kernel:

   - kprobes updates: use better W^X patterns for code modifications,
     improve optprobes, remove jprobes. (Masami Hiramatsu, Kees Cook)

   - core fixes: event timekeeping (enabled/running times statistics)
     fixes, perf_event_read() locking fixes and cleanups, etc. (Peter
     Zijlstra)

   - Extend x86 Intel free-running PEBS support and support x86
     user-register sampling in perf record and perf script. (Andi Kleen)

  Tooling:

   - Completely rework the way inline frames are handled. Instead of
     querying for the inline nodes on-demand in the individual tools, we
     now create proper callchain nodes for inlined frames. (Milian
     Wolff)

   - 'perf trace' updates (Arnaldo Carvalho de Melo)

   - Implement a way to print formatted output to per-event files in
     'perf script' to facilitate generate flamegraphs, elliminating the
     need to write scripts to do that separation (yuzhoujian, Arnaldo
     Carvalho de Melo)

   - Update vendor events JSON metrics for Intel's Broadwell, Broadwell
     Server, Haswell, Haswell Server, IvyBridge, IvyTown, JakeTown,
     Sandy Bridge, Skylake, SkyLake Server - and Goldmont Plus V1 (Andi
     Kleen, Kan Liang)

   - Multithread the synthesizing of PERF_RECORD_ events for
     pre-existing threads in 'perf top', speeding up that phase, greatly
     improving the user experience in systems such as Intel's Knights
     Mill (Kan Liang)

   - Introduce the concept of weak groups in 'perf stat': try to set up
     a group, but if it's not schedulable fallback to not using a group.
     That gives us the best of both worlds: groups if they work, but
     still a usable fallback if they don't. E.g: (Andi Kleen)

   - perf sched timehist enhancements (David Ahern)

   - ... various other enhancements, updates, cleanups and fixes"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (139 commits)
  kprobes: Don't spam the build log with deprecation warnings
  arm/kprobes: Remove jprobe test case
  arm/kprobes: Fix kretprobe test to check correct counter
  perf srcline: Show correct function name for srcline of callchains
  perf srcline: Fix memory leak in addr2inlines()
  perf trace beauty kcmp: Beautify arguments
  perf trace beauty: Implement pid_fd beautifier
  tools include uapi: Grab a copy of linux/kcmp.h
  perf callchain: Fix double mapping al->addr for children without self period
  perf stat: Make --per-thread update shadow stats to show metrics
  perf stat: Move the shadow stats scale computation in perf_stat__update_shadow_stats
  perf tools: Add perf_data_file__write function
  perf tools: Add struct perf_data_file
  perf tools: Rename struct perf_data_file to perf_data
  perf script: Print information about per-event-dump files
  perf trace beauty prctl: Generate 'option' string table from kernel headers
  tools include uapi: Grab a copy of linux/prctl.h
  perf script: Allow creating per-event dump files
  perf evsel: Restore evsel->priv as a tool private area
  perf script: Use event_format__fprintf()
  ...
2017-11-13 13:05:08 -08:00
David S. Miller f3edacbd69 bpf: Revert bpf_overrid_function() helper changes.
NACK'd by x86 maintainer.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11 18:24:55 +09:00
Josef Bacik dd0bb688ea bpf: add a bpf_override_function helper
Error injection is sloppy and very ad-hoc.  BPF could fill this niche
perfectly with it's kprobe functionality.  We could make sure errors are
only triggered in specific call chains that we care about with very
specific situations.  Accomplish this with the bpf_override_funciton
helper.  This will modify the probe'd callers return value to the
specified value and set the PC to an override function that simply
returns, bypassing the originally probed function.  This gives us a nice
clean way to implement systematic error injection for all of our code
paths.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11 12:18:05 +09:00
Jens Axboe a6da0024ff blktrace: fix unlocked registration of tracepoints
We need to ensure that tracepoints are registered and unregistered
with the users of them. The existing atomic count isn't enough for
that. Add a lock around the tracepoints, so we serialize access
to them.

This fixes cases where we have multiple users setting up and
tearing down tracepoints, like this:

CPU: 0 PID: 2995 Comm: syzkaller857118 Not tainted
4.14.0-rc5-next-20171018+ #36
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:16 [inline]
  dump_stack+0x194/0x257 lib/dump_stack.c:52
  panic+0x1e4/0x41c kernel/panic.c:183
  __warn+0x1c4/0x1e0 kernel/panic.c:546
  report_bug+0x211/0x2d0 lib/bug.c:183
  fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:177
  do_trap_no_signal arch/x86/kernel/traps.c:211 [inline]
  do_trap+0x260/0x390 arch/x86/kernel/traps.c:260
  do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:297
  do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:310
  invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:tracepoint_add_func kernel/tracepoint.c:210 [inline]
RIP: 0010:tracepoint_probe_register_prio+0x397/0x9a0 kernel/tracepoint.c:283
RSP: 0018:ffff8801d1d1f6c0 EFLAGS: 00010293
RAX: ffff8801d22e8540 RBX: 00000000ffffffef RCX: ffffffff81710f07
RDX: 0000000000000000 RSI: ffffffff85b679c0 RDI: ffff8801d5f19818
RBP: ffff8801d1d1f7c8 R08: ffffffff81710c10 R09: 0000000000000004
R10: ffff8801d1d1f6b0 R11: 0000000000000003 R12: ffffffff817597f0
R13: 0000000000000000 R14: 00000000ffffffff R15: ffff8801d1d1f7a0
  tracepoint_probe_register+0x2a/0x40 kernel/tracepoint.c:304
  register_trace_block_rq_insert include/trace/events/block.h:191 [inline]
  blk_register_tracepoints+0x1e/0x2f0 kernel/trace/blktrace.c:1043
  do_blk_trace_setup+0xa10/0xcf0 kernel/trace/blktrace.c:542
  blk_trace_setup+0xbd/0x180 kernel/trace/blktrace.c:564
  sg_ioctl+0xc71/0x2d90 drivers/scsi/sg.c:1089
  vfs_ioctl fs/ioctl.c:45 [inline]
  do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
  SYSC_ioctl fs/ioctl.c:700 [inline]
  SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
  entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x444339
RSP: 002b:00007ffe05bb5b18 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006d66c0 RCX: 0000000000444339
RDX: 000000002084cf90 RSI: 00000000c0481273 RDI: 0000000000000009
RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffffff
R13: 00000000c0481273 R14: 0000000000000000 R15: 0000000000000000

since we can now run these in parallel. Ensure that the exported helpers
for doing this are grabbing the queue trace mutex.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Jens Axboe 1f2cac107c blktrace: fix unlocked access to init/start-stop/teardown
sg.c calls into the blktrace functions without holding the proper queue
mutex for doing setup, start/stop, or teardown.

Add internal unlocked variants, and export the ones that do the proper
locking.

Fixes: 6da127ad09 ("blktrace: Add blktrace ioctls to SCSI generic devices")
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Ingo Molnar 8a103df440 Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-08 10:17:15 +01:00
Ingo Molnar 8c5db92a70 Merge branch 'linus' into locking/core, to resolve conflicts
Conflicts:
	include/linux/compiler-clang.h
	include/linux/compiler-gcc.h
	include/linux/compiler-intel.h
	include/uapi/linux/stddef.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:32:44 +01:00
Ingo Molnar 15bcdc9477 Merge branch 'linus' into perf/core, to fix conflicts
Conflicts:
	tools/perf/arch/arm/annotate/instructions.c
	tools/perf/arch/arm64/annotate/instructions.c
	tools/perf/arch/powerpc/annotate/instructions.c
	tools/perf/arch/s390/annotate/instructions.c
	tools/perf/arch/x86/tests/intel-cqm.c
	tools/perf/ui/tui/progress.c
	tools/perf/util/zlib.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:30:18 +01:00
David S. Miller 2a171788ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 09:26:51 +09:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Yonghong Song 07c41a295c bpf: avoid rcu_dereference inside bpf_event_mutex lock region
During perf event attaching/detaching bpf programs,
the tp_event->prog_array change is protected by the
bpf_event_mutex lock in both attaching and deteching
functions. Although tp_event->prog_array is a rcu
pointer, rcu_derefrence is not needed to access it
since mutex lock will guarantee ordering.

Verified through "make C=2" that sparse
locking check still happy with the new change.

Also change the label name in perf_event_{attach,detach}_bpf_prog
from "out" to "unlock" to reflect the code action after the label.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01 12:35:48 +09:00
Gianluca Borello 035226b964 bpf: remove tail_call and get_stackid helper declarations from bpf.h
commit afdb09c720 ("security: bpf: Add LSM hooks for bpf object related
syscall") included linux/bpf.h in linux/security.h. As a result, bpf
programs including bpf_helpers.h and some other header that ends up
pulling in also security.h, such as several examples under samples/bpf,
fail to compile because bpf_tail_call and bpf_get_stackid are now
"redefined as different kind of symbol".

>From bpf.h:

u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5);
u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);

Whereas in bpf_helpers.h they are:

static void (*bpf_tail_call)(void *ctx, void *map, int index);
static int (*bpf_get_stackid)(void *ctx, void *map, int flags);

Fix this by removing the unused declaration of bpf_tail_call and moving
the declaration of bpf_get_stackid in bpf_trace.c, which is the only
place where it's needed.

Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-27 22:14:22 +09:00
Yonghong Song 7d9285e82d perf/bpf: Extend the perf_event_read_local() interface, a.k.a. "bpf: perf event change needed for subsequent bpf helpers"
eBPF programs would like access to the (perf) event enabled and
running times along with the event value, such that they can deal with
event multiplexing (among other things).

This patch extends the interface; a future eBPF patch will utilize
the new functionality.

[ Note, there's a same-content commit with a poor changelog and a meaningless
  title in the networking tree as well - but we need this change for subsequent
  perf work, so apply it here as well, with a proper changelog. Hopefully Git
  will be able to sort out this somewhat messy workflow, if there are no other,
  conflicting changes to these files. ]

Signed-off-by: Yonghong Song <yhs@fb.com>
[ Rewrote the changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <ast@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David S. Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20171005161923.332790-2-yhs@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-27 10:31:56 +02:00
Mark Rutland 6aa7de0591 locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25 11:01:08 +02:00
Yonghong Song e87c6bc385 bpf: permit multiple bpf attachments for a single perf event
This patch enables multiple bpf attachments for a
kprobe/uprobe/tracepoint single trace event.
Each trace_event keeps a list of attached perf events.
When an event happens, all attached bpf programs will
be executed based on the order of attachment.

A global bpf_event_mutex lock is introduced to protect
prog_array attaching and detaching. An alternative will
be introduce a mutex lock in every trace_event_call
structure, but it takes a lot of extra memory.
So a global bpf_event_mutex lock is a good compromise.

The bpf prog detachment involves allocation of memory.
If the allocation fails, a dummy do-nothing program
will replace to-be-detached program in-place.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-25 10:47:47 +09:00
Jakub Kicinski 7de16e3a35 bpf: split verifier and program ops
struct bpf_verifier_ops contains both verifier ops and operations
used later during program's lifetime (test_run).  Split the runtime
ops into a different structure.

BPF_PROG_TYPE() will now append ## _prog_ops or ## _verifier_ops
to the names.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-18 14:17:10 +01:00
Peter Zijlstra b3a88803ac ftrace: Kill FTRACE_OPS_FL_PER_CPU
The one and only user of FTRACE_OPS_FL_PER_CPU is gone, remove the
lot.

Link: http://lkml.kernel.org/r/20171011080224.372422809@infradead.org

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-16 18:13:38 -04:00
Peter Zijlstra 1dd311e6dc perf/ftrace: Small cleanup
ops->flags _should_ be 0 at this point, so setting the flag using
bitwise or is a bit daft.

Link: http://lkml.kernel.org/r/20171011080224.315585202@infradead.org

Requested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-16 18:13:28 -04:00
Peter Zijlstra 466c81c45b perf/ftrace: Fix function trace events
The function-trace <-> perf interface is a tad messed up. Where all
the other trace <-> perf interfaces use a single trace hook
registration and use per-cpu RCU based hlist to iterate the events,
function-trace actually needs multiple hook registrations in order to
minimize function entry patching when filters are present.

The end result is that we iterate events both on the trace hook and on
the hlist, which results in reporting events multiple times.

Since function-trace cannot use the regular scheme, fix it the other
way around, use singleton hlists.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-16 18:12:21 -04:00
Peter Zijlstra 8fd0fbbe88 perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function")
Revert commit:

  75e8387685 ("perf/ftrace: Fix double traces of perf on ftrace:function")

The reason I instantly stumbled on that patch is that it only addresses the
ftrace situation and doesn't mention the other _5_ places that use this
interface. It doesn't explain why those don't have the problem and if not, why
their solution doesn't work for ftrace.

It doesn't, but this is just putting more duct tape on.

Link: http://lkml.kernel.org/r/20171011080224.200565770@infradead.org

Cc: Zhou Chengming <zhouchengming1@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-16 18:11:02 -04:00
Arnd Bergmann c3b5b6ed1e tracing: mark trace_test_buffer as __maybe_unused
After trace_selftest_startup_sched_switch is removed, trace_test_buffer()
is only used sometimes, leading to this warning:

kernel/trace/trace_selftest.c:62:12: error: 'trace_test_buffer' defined but not used [-Werror=unused-function]

There is no simple #ifdef condition that captures well whether the
function is in fact used or not, so marking it as __maybe_unused is
probably the best way to shut up the warning. The function will then
be silently dropped when there is no user.

Link: http://lkml.kernel.org/r/20171013142227.1273469-1-arnd@arndb.de

Fixes: d8c4deee6d ("tracing: Remove obsolete sched_switch tracer selftest")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-13 11:08:01 -04:00
Jesper Dangaard Brouer c5c1ea75a3 tracing: Kconfig text fixes for CONFIG_HWLAT_TRACER
Trivial spelling fixes for Kconfig help text of config HWLAT_TRACER.

Fixes: e7c15cd8a1 ("tracing: Added hardware latency tracer")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-10-12 15:28:23 +02:00
Joel Fernandes 8715b108cd ftrace: Clear hashes of stale ips of init memory
Filters should be cleared of init functions during freeing of init
memory when the ftrace dyn records are released. However in current
code, the filters are left as is. This patch clears the hashes of the
saved init functions when the init memory is freed. This fixes the
following issue reproducible with the following sequence of commands for
a test module:
================================================

void bar(void)
{
    printk(KERN_INFO "bar!\n");
}

void foo(void)
{
    printk(KERN_INFO "foo!\n");
    bar();
}

static int __init hello_init(void)
{
    printk(KERN_INFO "Hello world!\n");
    foo();
    return 0;
}

static void __exit hello_cleanup(void)
{
    printk(KERN_INFO "Cleaning up module.\n");
}

module_init(hello_init);
module_exit(hello_cleanup);
================================================

Commands:
echo '*:mod:test' > /d/tracing/set_ftrace_filter
echo function > /d/tracing/current_tracer
modprobe test
rmmod test
sleep 1
modprobe test
cat /d/tracing/set_ftrace_filter

Behavior without patch: Init function is still in the filter
Expected behavior: Shouldn't have any of the filters set

Link: http://lkml.kernel.org/r/20171009192931.56401-1-joelaf@google.com

Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-10 18:59:16 -04:00
Joel Fernandes d59158162e tracing: Add support for preempt and irq enable/disable events
Preempt and irq trace events can be used for tracing the start and
end of an atomic section which can be used by a trace viewer like
systrace to graphically view the start and end of an atomic section and
correlate them with latencies and scheduling issues.

This also serves as a prelude to using synthetic events or probes to
rewrite the preempt and irqsoff tracers, along with numerous benefits of
using trace events features for these events.
Link: http://lkml.kernel.org/r/20171006005432.14244-3-joelaf@google.com
Link: http://lkml.kernel.org/r/20171010225137.17370-1-joelaf@google.com

Cc: Peter Zilstra <peterz@infradead.org>
Cc: kernel-team@android.com
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-10 18:58:43 -04:00
Peter Zijlstra 1d48b080bc sched/debug: Rename task-state printing helpers
Steve requested better names for the new task-state helper functions.

So introduce the concept of task-state index for the printing and
rename __get_task_state() to task_state_index() and
__task_state_to_char() to task_index_to_char().

Requested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170929115016.pzlqc7ss3ccystyg@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-10 11:43:29 +02:00
Yonghong Song 4bebdc7a85 bpf: add helper bpf_perf_prog_read_value
This patch adds helper bpf_perf_prog_read_cvalue for perf event based bpf
programs, to read event counter and enabled/running time.
The enabled/running time is accumulated since the perf event open.

The typical use case for perf event based bpf program is to attach itself
to a single event. In such cases, if it is desirable to get scaling factor
between two bpf invocations, users can can save the time values in a map,
and use the value from the map and the current value to calculate
the scaling factor.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 23:05:57 +01:00
Yonghong Song 908432ca84 bpf: add helper bpf_perf_event_read_value for perf event array map
Hardware pmu counters are limited resources. When there are more
pmu based perf events opened than available counters, kernel will
multiplex these events so each event gets certain percentage
(but not 100%) of the pmu time. In case that multiplexing happens,
the number of samples or counter value will not reflect the
case compared to no multiplexing. This makes comparison between
different runs difficult.

Typically, the number of samples or counter value should be
normalized before comparing to other experiments. The typical
normalization is done like:
  normalized_num_samples = num_samples * time_enabled / time_running
  normalized_counter_value = counter_value * time_enabled / time_running
where time_enabled is the time enabled for event and time_running is
the time running for event since last normalization.

This patch adds helper bpf_perf_event_read_value for kprobed based perf
event array map, to read perf counter and enabled/running time.
The enabled/running time is accumulated since the perf event open.
To achieve scaling factor between two bpf invocations, users
can can use cpu_id as the key (which is typical for perf array usage model)
to remember the previous value and do the calculation inside the
bpf program.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 23:05:57 +01:00
Yonghong Song 97562633bc bpf: perf event change needed for subsequent bpf helpers
This patch does not impact existing functionalities.
It contains the changes in perf event area needed for
subsequent bpf_perf_event_read_value and
bpf_perf_prog_read_value helpers.

Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 23:05:57 +01:00
Joel Fernandes aaecaa0b5f tracing: Prepare to add preempt and irq trace events
In preparation of adding irqsoff and preemptsoff enable and disable trace
events, move required functions and code to make it easier to add these events
in a later patch. This patch is just code movement and no functional change.
Link: http://lkml.kernel.org/r/20171006005432.14244-2-joelaf@google.com

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@android.com
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-06 15:10:55 -04:00
Steven Rostedt (VMware) 6171a0310a ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions
If a module is loaded while tracing is enabled, then there's a possibility
that the module init functions were traced. These functions have their name
and address stored by ftrace such that it can translate the function address
that is written into the buffer into a human readable function name.

As userspace tools may be doing the same, they need a way to map function
names to their address as well. This is done through reading /proc/kallsyms.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-05 23:10:42 -04:00
Steven Rostedt (VMware) 6aa69784b4 ftrace: Add freeing algorithm to free ftrace_mod_maps
The ftrace_mod_map is a descriptor to save module init function names in
case they were traced, and the trace output needs to reference the function
name from the function address. But after the function is unloaded, it
the maps should be freed, as the rest of the function names are as well.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-05 17:57:34 -04:00
Steven Rostedt (VMware) aba4b5c22c ftrace: Save module init functions kallsyms symbols for tracing
If function tracing is active when the module init functions are freed, then
store them to be referenced by kallsyms. As module init functions can now be
traced on module load, they were useless:

 ># echo ':mod:snd_seq' > set_ftrace_filter
 ># echo function > current_tracer
 ># modprobe snd_seq
 ># cat trace
 # tracer: function
 #
 #                              _-----=> irqs-off
 #                             / _----=> need-resched
 #                            | / _---=> hardirq/softirq
 #                            || / _--=> preempt-depth
 #                            ||| /     delay
 #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
 #              | |       |   ||||       |         |
         modprobe-2786  [000] ....  3189.037874: 0xffffffffa0860000 <-do_one_initcall
         modprobe-2786  [000] ....  3189.037876: 0xffffffffa086004d <-0xffffffffa086000f
         modprobe-2786  [000] ....  3189.037876: 0xffffffffa086010d <-0xffffffffa0860018
         modprobe-2786  [000] ....  3189.037877: 0xffffffffa086011a <-0xffffffffa0860021
         modprobe-2786  [000] ....  3189.037877: 0xffffffffa0860080 <-0xffffffffa086002a
         modprobe-2786  [000] ....  3189.039523: 0xffffffffa0860400 <-0xffffffffa0860033
         modprobe-2786  [000] ....  3189.039523: 0xffffffffa086038a <-0xffffffffa086041c
         modprobe-2786  [000] ....  3189.039591: 0xffffffffa086038a <-0xffffffffa0860436
         modprobe-2786  [000] ....  3189.039657: 0xffffffffa086038a <-0xffffffffa0860450
         modprobe-2786  [000] ....  3189.039719: 0xffffffffa0860127 <-0xffffffffa086003c
         modprobe-2786  [000] ....  3189.039742: snd_seq_create_kernel_client <-0xffffffffa08601f6

When the output is shown, the kallsyms for the module init functions have
already been freed, and the output of the trace can not convert them to
their function names.

Now this looks like this:

 # tracer: function
 #
 #                              _-----=> irqs-off
 #                             / _----=> need-resched
 #                            | / _---=> hardirq/softirq
 #                            || / _--=> preempt-depth
 #                            ||| /     delay
 #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
 #              | |       |   ||||       |         |
         modprobe-2463  [002] ....   174.243237: alsa_seq_init <-do_one_initcall
         modprobe-2463  [002] ....   174.243239: client_init_data <-alsa_seq_init
         modprobe-2463  [002] ....   174.243240: snd_sequencer_memory_init <-alsa_seq_init
         modprobe-2463  [002] ....   174.243240: snd_seq_queues_init <-alsa_seq_init
         modprobe-2463  [002] ....   174.243240: snd_sequencer_device_init <-alsa_seq_init
         modprobe-2463  [002] ....   174.244860: snd_seq_info_init <-alsa_seq_init
         modprobe-2463  [002] ....   174.244861: create_info_entry <-snd_seq_info_init
         modprobe-2463  [002] ....   174.244936: create_info_entry <-snd_seq_info_init
         modprobe-2463  [002] ....   174.245003: create_info_entry <-snd_seq_info_init
         modprobe-2463  [002] ....   174.245072: snd_seq_system_client_init <-alsa_seq_init
         modprobe-2463  [002] ....   174.245094: snd_seq_create_kernel_client <-snd_seq_system_client_init

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-05 17:57:33 -04:00
Steven Rostedt (VMware) 3e234289f8 ftrace: Allow module init functions to be traced
Allow for module init sections to be traced as well as core kernel init
sections. Now that filtering modules functions can be stored, for when they
are loaded, it makes sense to be able to trace them.

Cc: Jessica Yu <jeyu@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-05 17:57:30 -04:00
Steven Rostedt (VMware) 6cafbe1594 ftrace: Add a ftrace_free_mem() function for modules to use
In order to be able to trace module init functions, the module code needs to
tell ftrace what is being freed when the init sections are freed. Use the
code that the main init calls to tell ftrace to free the main init sections.
This requires passing in a start and end address to free.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 14:20:52 -04:00
Tom Zanussi 5819eaddf3 tracing: Reimplement log2
log2 as currently implemented applies only to u64 trace_event_field
derived fields, and assumes that anything it's applied to is a u64
field.

To prepare for synthetic fields like latencies, log2 should be
applicable to those as well, so take the opportunity now to fix the
current problems as well as expand to more general uses.

log2 should be thought of as a chaining function rather than a field
type.  To enable this as well as possible future function
implementations, add a hist_field operand array into the hist_field
definition for this purpose, and make use of it to implement the log2
'function'.

Link: http://lkml.kernel.org/r/b47f93fc0b87b36eccf716b0c018f3a71e1f1111.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:10:39 -04:00
Tom Zanussi 85013256cf tracing: Add hist_field_name() accessor
In preparation for hist_fields that won't be strictly based on
trace_event_fields, add a new hist_field_name() accessor to allow that
flexibility and update associated users.

Link: http://lkml.kernel.org/r/5b5a2d36dde067cbbe2434b10f06daac27b7dbd5.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:09:09 -04:00
Tom Zanussi 0d7a8325bf tracing: Clean up hist_field_flags enum
As we add more flags, specifying explicit integers for the flag values
becomes more unwieldy and error-prone - switch them over to left-shift
values.

Link: http://lkml.kernel.org/r/e644e4fb7665aec015f4a2d84a2f990d3dd5b8a1.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:06:56 -04:00
Tom Zanussi 7e465baa80 tracing: Make traceprobe parsing code reusable
traceprobe_probes_write() and traceprobe_command() actually contain
nothing that ties them to kprobes - the code is generically useful for
similar types of parsing elsewhere, so separate it out and move it to
trace.c/trace.h.

Other than moving it, the only change is in naming:
traceprobe_probes_write() becomes trace_parse_run_command() and
traceprobe_command() becomes trace_run_command().

Link: http://lkml.kernel.org/r/ae5c26ea40c196a8986854d921eb6e713ede7e3f.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:06:44 -04:00
Tom Zanussi 4f36c2d85c tracing: Increase tracing map KEYS_MAX size
The current default for the number of subkeys in a compound key is 2,
which is too restrictive.  Increase it to a more realistic value of 3.

Link: http://lkml.kernel.org/r/b6952cca06d1f912eba33804a6fd6069b3847d44.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:06:25 -04:00
Tom Zanussi 83c07ecc42 tracing: Remove lookups from tracing_map hitcount
Lookups inflate the hitcount, making it essentially useless.  Only
inserts and updates should really affect the hitcount anyway, so
explicitly filter lookups out.

Link: http://lkml.kernel.org/r/c8d9dc39d269a8abf88bf4102d0dfc65deb0fc7f.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:05:42 -04:00
Tom Zanussi a15f7fc203 tracing: Exclude 'generic fields' from histograms
There are a small number of 'generic fields' (comm/COMM/cpu/CPU) that
are found by trace_find_event_field() but are only meant for
filtering.  Specifically, they unlike normal fields, they have a size
of 0 and thus wreak havoc when used as a histogram key.

Exclude these (return -EINVAL) when used as histogram keys.

Link: http://lkml.kernel.org/r/956154cbc3e8a4f0633d619b886c97f0f0edf7b4.1506105045.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 13:05:08 -04:00
Steven Rostedt (VMware) 1a149d7d3f ring-buffer: Rewrite trace_recursive_(un)lock() to be simpler
The current method to prevent the ring buffer from entering into a recursize
loop is to use a bitmask and set the bit that maps to the current context
(normal, softirq, irq or NMI), and if that bit was already set, it is
considered a recursive loop.

New code is being added that may require the ring buffer to be entered a
second time in the current context. The recursive locking prevents that from
happening. Instead of mapping a bitmask to the current context, just allow 4
levels of nesting in the ring buffer. This matches the 4 context levels that
it can already nest. It is highly unlikely to have more than two levels,
thus it should be fine when we add the second entry into the ring buffer. If
that proves to be a problem, we can always up the number to 8.

An added benefit is that reading preempt_count() to get the current level
adds a very slight but noticeable overhead. This removes that need.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 11:36:58 -04:00
Steven Rostedt (VMware) 12ecef0cb1 tracing: Reverse the order of trace_types_lock and event_mutex
In order to make future changes where we need to call
tracing_set_clock() from within an event command, the order of
trace_types_lock and event_mutex must be reversed, as the event command
will hold event_mutex and the trace_types_lock is taken from within
tracing_set_clock().

Link: http://lkml.kernel.org/r/20170921162249.0dde3dca@gandalf.local.home

Requested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 11:36:56 -04:00
Colin Ian King 6e7a239811 tracing: Remove redundant unread variable ret
Integer ret is being assigned but never used and hence it is
redundant. Remove it, fixes clang warning:

trace_events_hist.c:1077:3: warning: Value stored to 'ret' is never read

Link: http://lkml.kernel.org/r/20170823112309.19383-1-colin.king@canonical.com

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 11:36:55 -04:00
Joel Fernandes d8c4deee6d tracing: Remove obsolete sched_switch tracer selftest
Since commit 87d80de280 ("tracing: Remove
obsolete sched_switch tracer"), the sched_switch tracer selftest is no longer
used.  This patch removes the same.

Link: http://lkml.kernel.org/r/20170909065517.22262-1-joelaf@google.com

Cc: Ingo Molnar <mingo@redhat.com>
Cc: kernel-team@android.com
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04 11:36:54 -04:00
Linus Torvalds 013a8ee628 Two updates.
- A memory fix with left over code from spliting out ftrace_ops
    and function graph tracer, where the function graph tracer could
    reset the trampoline pointer, leaving the old trampoline not to
    be freed (memory leak).
 
  - The update to Paul's patch that added the unnecessary READ_ONCE().
    This removes the unnecessary READ_ONCE() instead of having to rebase
    the branch to update the patch that added it.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEEQEw9Eu0DdyUUkuUUybkF8mrZjcsFAlnU++sUHHJvc3RlZHRA
 Z29vZG1pcy5vcmcACgkQybkF8mrZjcujzgf/ebIzGKe5vQKNrL4ITAcIz0T7Hvzl
 pWw4uJp8kqO9x9EHMnztAkltQigvjvgDKZozJpUGgtNsFLuvdgQSBMK24YV8vLHs
 UmXEnQ2tSB/2Sg2ccEnpjVXaMzL9aqlbeTmACbdd9UgZnvPiUYPejq2jFfECFQjb
 k/gZT911ukBtx4mXYKzGFbTEZHdc/YUs6Y/wzB1ox5BBIUh71ZDZXxQTUHfXHlwS
 Cst69/9dKl4nBEGDGas6/95iR+ORVv85osI/pqPtjSj4EkRnWfVRotaH1kNuSQil
 gDIHSoy35NfXJx77/5IFHfrjFBAkr0IYRNL/jZaWazwM7rdqfAN8TwMQuA==
 =4CtF
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.14-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixlets from Steven Rostedt:
 "Two updates:

   - A memory fix with left over code from spliting out ftrace_ops and
     function graph tracer, where the function graph tracer could reset
     the trampoline pointer, leaving the old trampoline not to be freed
     (memory leak).

   - The update to Paul's patch that added the unnecessary READ_ONCE().
     This removes the unnecessary READ_ONCE() instead of having to
     rebase the branch to update the patch that added it"

* tag 'trace-v4.14-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  rcu: Remove extraneous READ_ONCE()s from rcu_irq_{enter,exit}()
  ftrace: Fix kmemleak in unregister_ftrace_graph
2017-10-04 08:34:01 -07:00