Pull user-space probe instrumentation from Ingo Molnar:
"The uprobes code originates from SystemTap and has been used for years
in Fedora and RHEL kernels. This version is much rewritten, reviews
from PeterZ, Oleg and myself shaped the end result.
This tree includes uprobes support in 'perf probe' - but SystemTap
(and other tools) can take advantage of user probe points as well.
Sample usage of uprobes via perf, for example to profile malloc()
calls without modifying user-space binaries.
First boot a new kernel with CONFIG_UPROBE_EVENT=y enabled.
If you don't know which function you want to probe you can pick one
from 'perf top' or can get a list all functions that can be probed
within libc (binaries can be specified as well):
$ perf probe -F -x /lib/libc.so.6
To probe libc's malloc():
$ perf probe -x /lib64/libc.so.6 malloc
Added new event:
probe_libc:malloc (on 0x7eac0)
You can now use it in all perf tools, such as:
perf record -e probe_libc:malloc -aR sleep 1
Make use of it to create a call graph (as the flat profile is going to
look very boring):
$ perf record -e probe_libc:malloc -gR make
[ perf record: Woken up 173 times to write data ]
[ perf record: Captured and wrote 44.190 MB perf.data (~1930712
$ perf report | less
32.03% git libc-2.15.so [.] malloc
|
--- malloc
29.49% cc1 libc-2.15.so [.] malloc
|
--- malloc
|
|--0.95%-- 0x208eb1000000000
|
|--0.63%-- htab_traverse_noresize
11.04% as libc-2.15.so [.] malloc
|
--- malloc
|
7.15% ld libc-2.15.so [.] malloc
|
--- malloc
|
5.07% sh libc-2.15.so [.] malloc
|
--- malloc
|
4.99% python-config libc-2.15.so [.] malloc
|
--- malloc
|
4.54% make libc-2.15.so [.] malloc
|
--- malloc
|
|--7.34%-- glob
| |
| |--93.18%-- 0x41588f
| |
| --6.82%-- glob
| 0x41588f
...
Or:
$ perf report -g flat | less
# Overhead Command Shared Object Symbol
# ........ ............. ............. ..........
#
32.03% git libc-2.15.so [.] malloc
27.19%
malloc
29.49% cc1 libc-2.15.so [.] malloc
24.77%
malloc
11.04% as libc-2.15.so [.] malloc
11.02%
malloc
7.15% ld libc-2.15.so [.] malloc
6.57%
malloc
...
The core uprobes design is fairly straightforward: uprobes probe
points register themselves at (inode:offset) addresses of
libraries/binaries, after which all existing (or new) vmas that map
that address will have a software breakpoint injected at that address.
vmas are COW-ed to preserve original content. The probe points are
kept in an rbtree.
If user-space executes the probed inode:offset instruction address
then an event is generated which can be recovered from the regular
perf event channels and mmap-ed ring-buffer.
Multiple probes at the same address are supported, they create a
dynamic callback list of event consumers.
The basic model is further complicated by the XOL speedup: the
original instruction that is probed is copied (in an architecture
specific fashion) and executed out of line when the probe triggers.
The XOL area is a single vma per process, with a fixed number of
entries (which limits probe execution parallelism).
The API: uprobes are installed/removed via
/sys/kernel/debug/tracing/uprobe_events, the API is integrated to
align with the kprobes interface as much as possible, but is separate
to it.
Injecting a probe point is privileged operation, which can be relaxed
by setting perf_paranoid to -1.
You can use multiple probes as well and mix them with kprobes and
regular PMU events or tracepoints, when instrumenting a task."
Fix up trivial conflicts in mm/memory.c due to previous cleanup of
unmap_single_vma().
* 'perf-uprobes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
perf probe: Detect probe target when m/x options are absent
perf probe: Provide perf interface for uprobes
tracing: Fix kconfig warning due to a typo
tracing: Provide trace events interface for uprobes
tracing: Extract out common code for kprobes/uprobes trace events
tracing: Modify is_delete, is_return from int to bool
uprobes/core: Decrement uprobe count before the pages are unmapped
uprobes/core: Make background page replacement logic account for rss_stat counters
uprobes/core: Optimize probe hits with the help of a counter
uprobes/core: Allocate XOL slots for uprobes use
uprobes/core: Handle breakpoint and singlestep exceptions
uprobes/core: Rename bkpt to swbp
uprobes/core: Make order of function parameters consistent across functions
uprobes/core: Make macro names consistent
uprobes: Update copyright notices
uprobes/core: Move insn to arch specific structure
uprobes/core: Remove uprobe_opcode_sz
uprobes/core: Make instruction tables volatile
uprobes: Move to kernel/events/
uprobes/core: Clean up, refactor and improve the code
...
Pull media updates from Mauro Carvalho Chehab:
- some V4L2 API updates needed by embedded devices
- DVB API extensions for ATSC-MH delivery system, used in US for mobile
TV
- new tuners for fc0011/0012/0013 and tua9001
- a new dvb driver for af9033/9035
- a new ATSC-MH frontend (lg2160)
- new remote controller keymaps
- Removal of a few legacy webcam driver that got replaced by gspca on
several kernel versions ago
- a new driver for Exynos 4/5 webcams(s5pp fimc-lite)
- a new webcam sensor driver (smiapp)
- a new video input driver for embedded (sta2x1xx)
- several improvements, fixes, cleanups, etc inside the drivers.
Manually fix up conflicts due to err() -> dev_err() conversion in
drivers/staging/media/easycap/easycap_main.c
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (484 commits)
[media] saa7134-cards: Remove a PCI entry added by mistake
[media] radio-sf16fmi: add support for SF16-FMD
[media] rc-loopback: remove duplicate line
[media] patch for Asus My Cinema PS3-100 (1043:48cd)
[media] au0828: Move the Kconfig knob under V4L_USB_DRIVERS
[media] em28xx: simple comment fix
[media] [resend] radio-sf16fmr2: add PnP support for SF16-FMD2
[media] smiapp: Use v4l2_ctrl_new_int_menu() instead of v4l2_ctrl_new_custom()
[media] smiapp: Add support for 8-bit uncompressed formats
[media] smiapp: Allow generic quirk registers
[media] smiapp: Use non-binning limits if the binning limit is zero
[media] smiapp: Initialise rval in smiapp_read_nvm()
[media] smiapp: Round minimum pre_pll up rather than down in ip_clk_freq check
[media] smiapp: Use 8-bit reads only before identifying the sensor
[media] smiapp: Quirk for sensors that only do 8-bit reads
[media] smiapp: Pass struct sensor to register writing commands instead of i2c_client
[media] smiapp: Allow using external clock from the clock framework
[media] zl10353: change .read_snr() to report SNR as a 0.1 dB
[media] media: add support to gspca/pac7302.c for 093a:2627 (Genius FaceCam 300)
[media] m88rs2000 - only flip bit 2 on reg 0x70 on 16th try
...
Pull an ftrace ring-buffer fix from Steve Rostedt:
* fix kernel crash when changing the size of the ring-buffer on
boxes where possible_cpus != online_cpus.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
UDP stack needs a minimum hash size value for proper operation and also
uses alloc_large_system_hash() for proper NUMA distribution of its hash
tables and automatic sizing depending on available system memory.
On some low memory situations, udp_table_init() must ignore the
alloc_large_system_hash() result and reallocs a bigger memory area.
As we cannot easily free old hash table, we leak it and kmemleak can
issue a warning.
This patch adds a low limit parameter to alloc_large_system_hash() to
solve this problem.
We then specify UDP_HTABLE_SIZE_MIN for UDP/UDPLite hash table
allocation.
Reported-by: Mark Asselstine <mark.asselstine@windriver.com>
Reported-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kill the no longer used task_struct->replacement_session_keyring, update
copy_creds() and exit_creds().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Smith <dsmith@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
exit_irq_thread() and task->irq_thread are needed to handle the unexpected
(and unlikely) exit of irq-thread.
We can use task_work instead and make this all private to
kernel/irq/manage.c, cleanup plus micro-optimization.
1. rename exit_irq_thread() to irq_thread_dtor(), make it
static, and move it up before irq_thread().
2. change irq_thread() to do task_work_add(irq_thread_dtor)
at the start and task_work_cancel() before return.
tracehook_notify_resume() can never play with kthreads,
only do_exit()->exit_task_work() can call the callback
and this is what we want.
3. remove task_struct->irq_thread and the special hook
in do_exit().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Smith <dsmith@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Provide a simple mechanism that allows running code in the (nonatomic)
context of the arbitrary task.
The caller does task_work_add(task, task_work) and this task executes
task_work->func() either from do_notify_resume() or from do_exit(). The
callback can rely on PF_EXITING to detect the latter case.
"struct task_work" can be embedded in another struct, still it has "void
*data" to handle the most common/simple case.
This allows us to kill the ->replacement_session_keyring hack, and
potentially this can have more users.
Performance-wise, this adds 2 "unlikely(!hlist_empty())" checks into
tracehook_notify_resume() and do_exit(). But at the same time we can
remove the "replacement_session_keyring != NULL" checks from
arch/*/signal.c and exit_creds().
Note: task_work_add/task_work_run abuses ->pi_lock. This is only because
this lock is already used by lookup_pi_state() to synchronize with
do_exit() setting PF_EXITING. Fortunately the scope of this lock in
task_work.c is really tiny, and the code is unlikely anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Smith <dsmith@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull first series of signal handling cleanups from Al Viro:
"This is just the first part of the queue (about a half of it);
assorted fixes all over the place in signal handling.
This one ends with all sigsuspend() implementations switched to
generic one (->saved_sigmask-based).
With this, a bunch of assorted old buglets are fixed and most of the
missing bits of NOTIFY_RESUME hookup are in place. Two more fixes sit
in arm and um trees respectively, and there's a couple of broken ones
that need obvious fixes - parisc and avr32 check TIF_NOTIFY_RESUME
only on one of two codepaths; fixes for that will happen in the next
series"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (55 commits)
unicore32: if there's no handler we need to restore sigmask, syscall or no syscall
xtensa: add handling of TIF_NOTIFY_RESUME
microblaze: drop 'oldset' argument of do_notify_resume()
microblaze: handle TIF_NOTIFY_RESUME
score: add handling of NOTIFY_RESUME to do_notify_resume()
m68k: add TIF_NOTIFY_RESUME and handle it.
sparc: kill ancient comment in sparc_sigaction()
h8300: missing checks of __get_user()/__put_user() return values
frv: missing checks of __get_user()/__put_user() return values
cris: missing checks of __get_user()/__put_user() return values
powerpc: missing checks of __get_user()/__put_user() return values
sh: missing checks of __get_user()/__put_user() return values
sparc: missing checks of __get_user()/__put_user() return values
avr32: struct old_sigaction is never used
m32r: struct old_sigaction is never used
xtensa: xtensa_sigaction doesn't exist
alpha: tidy signal delivery up
score: don't open-code force_sigsegv()
cris: don't open-code force_sigsegv()
blackfin: don't open-code force_sigsegv()
...
Pull user namespace enhancements from Eric Biederman:
"This is a course correction for the user namespace, so that we can
reach an inexpensive, maintainable, and reasonably complete
implementation.
Highlights:
- Config guards make it impossible to enable the user namespace and
code that has not been converted to be user namespace safe.
- Use of the new kuid_t type ensures the if you somehow get past the
config guards the kernel will encounter type errors if you enable
user namespaces and attempt to compile in code whose permission
checks have not been updated to be user namespace safe.
- All uids from child user namespaces are mapped into the initial
user namespace before they are processed. Removing the need to add
an additional check to see if the user namespace of the compared
uids remains the same.
- With the user namespaces compiled out the performance is as good or
better than it is today.
- For most operations absolutely nothing changes performance or
operationally with the user namespace enabled.
- The worst case performance I could come up with was timing 1
billion cache cold stat operations with the user namespace code
enabled. This went from 156s to 164s on my laptop (or 156ns to
164ns per stat operation).
- (uid_t)-1 and (gid_t)-1 are reserved as an internal error value.
Most uid/gid setting system calls treat these value specially
anyway so attempting to use -1 as a uid would likely cause
entertaining failures in userspace.
- If setuid is called with a uid that can not be mapped setuid fails.
I have looked at sendmail, login, ssh and every other program I
could think of that would call setuid and they all check for and
handle the case where setuid fails.
- If stat or a similar system call is called from a context in which
we can not map a uid we lie and return overflowuid. The LFS
experience suggests not lying and returning an error code might be
better, but the historical precedent with uids is different and I
can not think of anything that would break by lying about a uid we
can't map.
- Capabilities are localized to the current user namespace making it
safe to give the initial user in a user namespace all capabilities.
My git tree covers all of the modifications needed to convert the core
kernel and enough changes to make a system bootable to runlevel 1."
Fix up trivial conflicts due to nearby independent changes in fs/stat.c
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
userns: Silence silly gcc warning.
cred: use correct cred accessor with regards to rcu read lock
userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq
userns: Convert cgroup permission checks to use uid_eq
userns: Convert tmpfs to use kuid and kgid where appropriate
userns: Convert sysfs to use kgid/kuid where appropriate
userns: Convert sysctl permission checks to use kuid and kgids.
userns: Convert proc to use kuid/kgid where appropriate
userns: Convert ext4 to user kuid/kgid where appropriate
userns: Convert ext3 to use kuid/kgid where appropriate
userns: Convert ext2 to use kuid/kgid where appropriate.
userns: Convert devpts to use kuid/kgid where appropriate
userns: Convert binary formats to use kuid/kgid where appropriate
userns: Add negative depends on entries to avoid building code that is userns unsafe
userns: signal remove unnecessary map_cred_ns
userns: Teach inode_capable to understand inodes whose uids map to other namespaces.
userns: Fail exec for suid and sgid binaries with ids outside our user namespace.
userns: Convert stat to return values mapped from kuids and kgids
userns: Convert user specfied uids and gids in chown into kuids and kgid
userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs
...
Fortunately David Howells is looking to change this, with his module signing
patchset. But that's for next merge window...
Cheers,
Rusty.
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Merge tag 'module-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
Pull module patches from Rusty Russell, who really sells them:
"Three trivial patches of no real utility. Modules are boring."
But to make things slightly more exciting, he adds:
"Fortunately David Howells is looking to change this, with his module
signing patchset. But that's for next merge window...
Cheers,
Rusty."
* tag 'module-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
Guard check in module loader against integer overflow
modpost: use proper kernel style for autogenerated files
modpost: Stop grab_file() from leaking filedescriptors if fstat() fails
* Implementation of opportunistic suspend (autosleep) and user space interface
for manipulating wakeup sources.
* Hibernate updates from Bojan Smojver and Minho Ban.
* Updates of the runtime PM core and generic PM domains framework related to
PM QoS.
* Assorted fixes.
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Merge tag 'pm-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
- Implementation of opportunistic suspend (autosleep) and user space
interface for manipulating wakeup sources.
- Hibernate updates from Bojan Smojver and Minho Ban.
- Updates of the runtime PM core and generic PM domains framework
related to PM QoS.
- Assorted fixes.
* tag 'pm-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits)
epoll: Fix user space breakage related to EPOLLWAKEUP
PM / Domains: Make it possible to add devices to inactive domains
PM / Hibernate: Use get_gendisk to verify partition if resume_file is integer format
PM / Domains: Fix computation of maximum domain off time
PM / Domains: Fix link checking when add subdomain
PM / Sleep: User space wakeup sources garbage collector Kconfig option
PM / Sleep: Make the limit of user space wakeup sources configurable
PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo
PM / Domains: Cache device stop and domain power off governor results, v3
PM / Domains: Make device removal more straightforward
PM / Sleep: Fix a mistake in a conditional in autosleep_store()
epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready
PM / QoS: Create device constraints objects on notifier registration
PM / Runtime: Remove device fields related to suspend time, v2
PM / Domains: Rework default domain power off governor function, v2
PM / Domains: Rework default device stop governor function, v2
PM / Sleep: Add user space interface for manipulating wakeup sources, v3
PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources
PM / Sleep: Implement opportunistic sleep, v2
PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints
...
On some machines the number of possible CPUS is not the same as the
number of CPUs that is on the machine. Ftrace uses possible_cpus to
update the tracing structures but the ring buffer only allocates
per cpu buffers for online CPUs when they come up.
When the wakeup tracer was enabled in such a case, the ftrace code
enabled all possible cpu buffers, but the code in ring_buffer_resize()
did not check to see if the buffer in question was allocated. Since
boot up CPUs did not match possible CPUs it caused the following
crash:
BUG: unable to handle kernel NULL pointer dereference at 00000020
IP: [<c1097851>] ring_buffer_resize+0x16a/0x28d
*pde = 00000000
Oops: 0000 [#1] PREEMPT SMP
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in: [last unloaded: scsi_wait_scan]
Pid: 1387, comm: bash Not tainted 3.4.0-test+ #13 /DG965MQ
EIP: 0060:[<c1097851>] EFLAGS: 00010217 CPU: 0
EIP is at ring_buffer_resize+0x16a/0x28d
EAX: f5a14340 EBX: f6026b80 ECX: 00000ff4 EDX: 00000ff3
ESI: 00000000 EDI: 00000002 EBP: f4275ecc ESP: f4275eb0
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 80050033 CR2: 00000020 CR3: 34396000 CR4: 000007d0
DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
DR6: ffff0ff0 DR7: 00000400
Process bash (pid: 1387, ti=f4274000 task=f4380cb0 task.ti=f4274000)
Stack:
c109cf9a f6026b98 00000162 00160f68 00000006 00160f68 00000002 f4275ef0
c109d013 f4275ee8 c123b72a c1c0bf00 c1cc81dc 00000005 f4275f98 00000007
f4275f70 c109d0c7 7700000e 75656b61 00000070 f5e90900 f5c4e198 00000301
Call Trace:
[<c109cf9a>] ? tracing_set_tracer+0x115/0x1e9
[<c109d013>] tracing_set_tracer+0x18e/0x1e9
[<c123b72a>] ? _copy_from_user+0x30/0x46
[<c109d0c7>] tracing_set_trace_write+0x59/0x7f
[<c10ec01e>] ? fput+0x18/0x1c6
[<c11f8732>] ? security_file_permission+0x27/0x2b
[<c10eaacd>] ? rw_verify_area+0xcf/0xf2
[<c10ec01e>] ? fput+0x18/0x1c6
[<c109d06e>] ? tracing_set_tracer+0x1e9/0x1e9
[<c10ead77>] vfs_write+0x8b/0xe3
[<c10ebead>] ? fget_light+0x30/0x81
[<c10eaf54>] sys_write+0x42/0x63
[<c1834fbf>] sysenter_do_call+0x12/0x28
This happens with the latency tracer as the ftrace code updates the
saved max buffer via its cpumask and not with a global setting.
Adding a check in ring_buffer_resize() to make sure the buffer being resized
exists, fixes the problem.
Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull perf fixes from Ingo Molnar:
- Leftover AMD PMU driver fix fix from the end of the v3.4
stabilization cycle.
- Late tools/perf/ changes that missed the first round:
* endianness fixes
* event parsing improvements
* libtraceevent fixes factored out from trace-cmd
* perl scripting engine fixes related to libtraceevent,
* testcase improvements
* perf inject / pipe mode fixes
* plus a kernel side fix
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Update event scheduling constraints for AMD family 15h models
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "sched, perf: Use a single callback into the scheduler"
perf evlist: Show event attribute details
perf tools: Bump default sample freq to 4 kHz
perf buildid-list: Work better with pipe mode
perf tools: Fix piped mode read code
perf inject: Fix broken perf inject -b
perf tools: rename HEADER_TRACE_INFO to HEADER_TRACING_DATA
perf tools: Add union u64_swap type for swapping u64 data
perf tools: Carry perf_event_attr bitfield throught different endians
perf record: Fix documentation for branch stack sampling
perf target: Add cpu flag to sample_type if target has cpu
perf tools: Always try to build libtraceevent
perf tools: Rename libparsevent to libtraceevent in Makefile
perf script: Rename struct event to struct event_format in perl engine
perf script: Explicitly handle known default print arg type
perf tools: Add hardcoded name term for pmu events
perf tools: Separate 'mem:' event scanner bits
perf tools: Use allocated list for each parsed event
perf tools: Add support for displaying event parser debug info
perf test: Move parse event automated tests to separated object
Pull fpu state cleanups from Ingo Molnar:
"This tree streamlines further aspects of FPU handling by eliminating
the prepare_to_copy() complication and moving that logic to
arch_dup_task_struct().
It also fixes the FPU dumps in threaded core dumps, removes and old
(and now invalid) assumption plus micro-optimizes the exit path by
avoiding an FPU save for dead tasks."
Fixed up trivial add-add conflict in arch/sh/kernel/process.c that came
in because we now do the FPU handling in arch_dup_task_struct() rather
than the legacy (and now gone) prepare_to_copy().
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, fpu: drop the fpu state during thread exit
x86, xsave: remove thread_has_fpu() bug check in __sanitize_i387_state()
coredump: ensure the fpu state is flushed for proper multi-threaded core dump
fork: move the real prepare_to_copy() users to arch_dup_task_struct()
Pull exception table generation updates from Ingo Molnar:
"The biggest change here is to allow the build-time sorting of the
exception table, to speed up booting. This is achieved by the
architecture enabling BUILDTIME_EXTABLE_SORT. This option is enabled
for x86 and MIPS currently.
On x86 a number of fixes and changes were needed to allow build-time
sorting of the exception table, in particular a relocation invariant
exception table format was needed. This required the abstracting out
of exception table protocol and the removal of 20 years of accumulated
assumptions about the x86 exception table format.
While at it, this tree also cleans up various other aspects of
exception handling, such as early(er) exception handling for
rdmsr_safe() et al.
All in one, as the result of these changes the x86 exception code is
now pretty nice and modern. As an added bonus any regressions in this
code will be early and violent crashes, so if you see any of those,
you'll know whom to blame!"
Fix up trivial conflicts in arch/{mips,x86}/Kconfig files due to nearby
modifications of other core architecture options.
* 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
Revert "x86, extable: Disable presorted exception table for now"
scripts/sortextable: Handle relative entries, and other cleanups
x86, extable: Switch to relative exception table entries
x86, extable: Disable presorted exception table for now
x86, extable: Add _ASM_EXTABLE_EX() macro
x86, extable: Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S
x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/xsave.h
x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/kvm_host.h
x86, extable: Remove the now-unused __ASM_EX_SEC macros
x86, extable: Remove open-coded exception table entries in arch/x86/xen/xen-asm_32.S
x86, extable: Remove open-coded exception table entries in arch/x86/um/checksum_32.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c
x86, extable: Remove open-coded exception table entries in arch/x86/lib/putuser.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/getuser.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/csum-copy_64.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S
x86, extable: Remove open-coded exception table entries in arch/x86/lib/checksum_32.S
x86, extable: Remove open-coded exception table entries in arch/x86/kernel/test_rodata.c
x86, extable: Remove open-coded exception table entries in arch/x86/kernel/entry_64.S
...
Pull UML updates from Richard Weinberger:
"Most changes are bug fixes and cleanups"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: missing checks of __put_user()/__get_user() return values
um: stub_rt_sigsuspend isn't needed these days anymore
um/x86: merge (and trim) 32- and 64-bit variants of ptrace.h
irq: Remove irq_chip->release()
um: Remove CONFIG_IRQ_RELEASE_METHOD
um: Remove usage of irq_chip->release()
um: Implement um_free_irq()
um: Fix __swp_type()
um: Implement a custom pte_same() function
um: Add BUG() to do_ops()'s error path
um: Remove unused variables
um: bury unused _TIF_RESTORE_SIGMASK
um: wrong sigmask saved in case of multiple sigframes
um: add TIF_NOTIFY_RESUME
um: ->restart_block.fn needs to be reset on sigreturn
This reverts commit cb04ff9ac4 ("sched, perf: Use a single
callback into the scheduler").
Before this change was introduced, the process switch worked
like this (wrt. to perf event schedule):
schedule (prev, next)
- schedule out all perf events for prev
- switch to next
- schedule in all perf events for current (next)
After the commit, the process switch looks like:
schedule (prev, next)
- schedule out all perf events for prev
- schedule in all perf events for (next)
- switch to next
The problem is, that after we schedule perf events in, the pmu
is enabled and we can receive events even before we make the
switch to next - so "current" still being prev process (event
SAMPLE data are filled based on the value of the "current"
process).
Thats exactly what we see for test__PERF_RECORD test. We receive
SAMPLES with PID of the process that our tracee is scheduled
from.
Discussed with Peter Zijlstra:
> Bah!, yeah I guess reverting is the right thing for now. Sad
> though.
>
> So by having the two hooks we have a black-spot between them
> where we receive no events at all, this black-spot covers the
> hand-over of current and we thus don't receive the 'wrong'
> events.
>
> I rather liked we could do away with both that black-spot and
> clean up the code a little, but apparently people rely on it.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: acme@redhat.com
Cc: paulus@samba.org
Cc: cjashfor@linux.vnet.ibm.com
Cc: fweisbec@gmail.com
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/20120523111302.GC1638@m.brq.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The check:
if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
may not work if there's an overflow in the right-hand side of the condition.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Pull trivial updates from Jiri Kosina:
"As usual, it's mostly typo fixes, redundant code elimination and some
documentation updates."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (57 commits)
edac, mips: don't change code that has been removed in edac/mips tree
xtensa: Change mail addresses of Hannes Weiner and Oskar Schirmer
lib: Change mail address of Oskar Schirmer
net: Change mail address of Oskar Schirmer
arm/m68k: Change mail address of Sebastian Hess
i2c: Change mail address of Oskar Schirmer
net: Fix tcp_build_and_update_options comment in struct tcp_sock
atomic64_32.h: fix parameter naming mismatch
Kconfig: replace "--- help ---" with "---help---"
c2port: fix bogus Kconfig "default no"
edac: Fix spelling errors.
qla1280: Remove redundant NULL check before release_firmware() call
remoteproc: remove redundant NULL check before release_firmware()
qla2xxx: Remove redundant NULL check before release_firmware() call.
aic94xx: Get rid of redundant NULL check before release_firmware() call
tehuti: delete redundant NULL check before release_firmware()
qlogic: get rid of a redundant test for NULL before call to release_firmware()
bna: remove redundant NULL test before release_firmware()
tg3: remove redundant NULL test before release_firmware() call
typhoon: get rid of redundant conditional before all to release_firmware()
...
Pull scheduler changes from Ingo Molnar:
"The biggest change is the cleanup/simplification of the load-balancer:
instead of the current practice of architectures twiddling scheduler
internal data structures and providing the scheduler domains in
colorfully inconsistent ways, we now have generic scheduler code in
kernel/sched/core.c:sched_init_numa() that looks at the architecture's
node_distance() parameters and (while not fully trusting it) deducts a
NUMA topology from it.
This inevitably changes balancing behavior - hopefully for the better.
There are various smaller optimizations, cleanups and fixlets as well"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Taint kernel with TAINT_WARN after sleep-in-atomic bug
sched: Remove stale power aware scheduling remnants and dysfunctional knobs
sched/debug: Fix printing large integers on 32-bit platforms
sched/fair: Improve the ->group_imb logic
sched/nohz: Fix rq->cpu_load[] calculations
sched/numa: Don't scale the imbalance
sched/fair: Revert sched-domain iteration breakage
sched/x86: Rewrite set_cpu_sibling_map()
sched/numa: Fix the new NUMA topology bits
sched/numa: Rewrite the CONFIG_NUMA sched domain support
sched/fair: Propagate 'struct lb_env' usage into find_busiest_group
sched/fair: Add some serialization to the sched_domain load-balance walk
sched/fair: Let minimally loaded cpu balance the group
sched: Change rq->nr_running to unsigned int
x86/numa: Check for nonsensical topologies on real hw as well
x86/numa: Hard partition cpu topology masks on node boundaries
x86/numa: Allow specifying node_distance() for numa=fake
x86/sched: Make mwait_usable() heed to "idle=" kernel parameters properly
sched: Update documentation and comments
sched_rt: Avoid unnecessary dequeue and enqueue of pushable tasks in set_cpus_allowed_rt()
Pull perf changes from Ingo Molnar:
"Lots of changes:
- (much) improved assembly annotation support in perf report, with
jump visualization, searching, navigation, visual output
improvements and more.
- kernel support for AMD IBS PMU hardware features. Notably 'perf
record -e cycles:p' and 'perf top -e cycles:p' should work without
skid now, like PEBS does on the Intel side, because it takes
advantage of IBS transparently.
- the libtracevents library: it is the first step towards unifying
tracing tooling and perf, and it also gives a tracing library for
external tools like powertop to rely on.
- infrastructure: various improvements and refactoring of the UI
modules and related code
- infrastructure: cleanup and simplification of the profiling
targets code (--uid, --pid, --tid, --cpu, --all-cpus, etc.)
- tons of robustness fixes all around
- various ftrace updates: speedups, cleanups, robustness
improvements.
- typing 'make' in tools/ will now give you a menu of projects to
build and a short help text to explain what each does.
- ... and lots of other changes I forgot to list.
The perf record make bzImage + perf report regression you reported
should be fixed."
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (166 commits)
tracing: Remove kernel_lock annotations
tracing: Fix initial buffer_size_kb state
ring-buffer: Merge separate resize loops
perf evsel: Create events initially disabled -- again
perf tools: Split term type into value type and term type
perf hists: Fix callchain ip printf format
perf target: Add uses_mmap field
ftrace: Remove selecting FRAME_POINTER with FUNCTION_TRACER
ftrace/x86: Have x86 ftrace use the ftrace_modify_all_code()
ftrace: Make ftrace_modify_all_code() global for archs to use
ftrace: Return record ip addr for ftrace_location()
ftrace: Consolidate ftrace_location() and ftrace_text_reserved()
ftrace: Speed up search by skipping pages by address
ftrace: Remove extra helper functions
ftrace: Sort all function addresses, not just per page
tracing: change CPU ring buffer state from tracing_cpumask
tracing: Check return value of tracing_dentry_percpu()
ring-buffer: Reset head page before running self test
ring-buffer: Add integrity check at end of iter read
ring-buffer: Make addition of pages in ring buffer atomic
...
Pull cgroup updates from Tejun Heo:
"cgroup file type addition / removal is updated so that file types are
added and removed instead of individual files so that dynamic file
type addition / removal can be implemented by cgroup and used by
controllers. blkio controller changes which will come through block
tree are dependent on this. Other changes include res_counter cleanup
and disallowing kthread / PF_THREAD_BOUND threads to be attached to
non-root cgroups.
There's a reported bug with the file type addition / removal handling
which can lead to oops on cgroup umount. The issue is being looked
into. It shouldn't cause problems for most setups and isn't a
security concern."
Fix up trivial conflict in Documentation/feature-removal-schedule.txt
* 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits)
res_counter: Account max_usage when calling res_counter_charge_nofail()
res_counter: Merge res_counter_charge and res_counter_charge_nofail
cgroups: disallow attaching kthreadd or PF_THREAD_BOUND threads
cgroup: remove cgroup_subsys->populate()
cgroup: get rid of populate for memcg
cgroup: pass struct mem_cgroup instead of struct cgroup to socket memcg
cgroup: make css->refcnt clearing on cgroup removal optional
cgroup: use negative bias on css->refcnt to block css_tryget()
cgroup: implement cgroup_rm_cftypes()
cgroup: introduce struct cfent
cgroup: relocate __d_cgrp() and __d_cft()
cgroup: remove cgroup_add_file[s]()
cgroup: convert memcg controller to the new cftype interface
memcg: always create memsw files if CONFIG_CGROUP_MEM_RES_CTLR_SWAP
cgroup: convert all non-memcg controllers to the new cftype interface
cgroup: relocate cftype and cgroup_subsys definitions in controllers
cgroup: merge cft_release_agent cftype array into the base files array
cgroup: implement cgroup_add_cftypes() and friends
cgroup: build list of all cgroups under a given cgroupfs_root
cgroup: move cgroup_clear_directory() call out of cgroup_populate_dir()
...
Pull workqueue changes from Tejun Heo:
"Nothing exciting. Most are updates to debug stuff and related fixes.
Two not-too-critical bugs are fixed - WARN_ON() triggering spurious
during cpu offlining and unlikely lockdep related oops."
* 'for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
lockdep: fix oops in processing workqueue
workqueue: skip nr_running sanity check in worker_enter_idle() if trustee is active
workqueue: Catch more locking problems with flush_work()
workqueue: change BUG_ON() to WARN_ON()
trace: Remove unused workqueue tracer
Here is the big staging tree pull request for the 3.5-rc1 merge window.
Loads of changes here, and we just narrowly added more lines than we
added:
622 files changed, 28356 insertions(+), 26059 deletions(-)
But, good news is that there is a number of subsystems that moved out of
the staging tree, to their respective "real" portions of the kernel.
Code that moved out was:
- iio core code
- mei driver
- vme core and bridge drivers
There was one broken network driver that moved into staging as a step
before it is removed from the tree (pc300), and there was a few new
drivers added to the tree:
- new iio drivers
- gdm72xx wimax USB driver
- ipack subsystem and 2 drivers
All of the movements around have acks from the various subsystem
maintainers, and all of this has been in the linux-next tree for a
while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging tree changes from Greg Kroah-Hartman:
"Here is the big staging tree pull request for the 3.5-rc1 merge
window.
Loads of changes here, and we just narrowly added more lines than we
added:
622 files changed, 28356 insertions(+), 26059 deletions(-)
But, good news is that there is a number of subsystems that moved out
of the staging tree, to their respective "real" portions of the
kernel.
Code that moved out was:
- iio core code
- mei driver
- vme core and bridge drivers
There was one broken network driver that moved into staging as a step
before it is removed from the tree (pc300), and there was a few new
drivers added to the tree:
- new iio drivers
- gdm72xx wimax USB driver
- ipack subsystem and 2 drivers
All of the movements around have acks from the various subsystem
maintainers, and all of this has been in the linux-next tree for a
while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
Fixed up various trivial conflicts, along with a non-trivial one found
in -next and pointed out by Olof Johanssen: a clean - but incorrect -
merge of the arch/arm/boot/dts/at91sam9g20.dtsi file. Fix up manually
as per Stephen Rothwell.
* tag 'staging-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (536 commits)
Staging: bcm: Remove two unused variables from Adapter.h
Staging: bcm: Removes the volatile type definition from Adapter.h
Staging: bcm: Rename all "INT" to "int" in Adapter.h
Staging: bcm: Fix warning: __packed vs. __attribute__((packed)) in Adapter.h
Staging: bcm: Correctly format all comments in Adapter.h
Staging: bcm: Fix all whitespace issues in Adapter.h
Staging: bcm: Properly format braces in Adapter.h
Staging: ipack/bridges/tpci200: remove unneeded casts
Staging: ipack/bridges/tpci200: remove TPCI200_SHORTNAME constant
Staging: ipack: remove board_name and bus_name fields from struct ipack_device
Staging: ipack: improve the register of a bus and a device in the bus.
staging: comedi: cleanup all the comedi_driver 'detach' functions
staging: comedi: remove all 'default N' in Kconfig
staging: line6/config.h: Delete unused header
staging: gdm72xx depends on NET
staging: gdm72xx: Set up parent link in sysfs for gdm72xx devices
staging: drm/omap: initial dmabuf/prime import support
staging: drm/omap: dmabuf/prime mmap support
pstore/ram: Add ECC support
pstore/ram: Switch to persistent_ram routines
...
Here's the driver core, and other driver subsystems, pull request for
the 3.5-rc1 merge window.
Outside of a few minor driver core changes, we ended up with the
following different subsystem and core changes as well, due to
interdependancies on the driver core:
- hyperv driver updates
- drivers/memory being created and some drivers moved into it
- extcon driver subsystem created out of the old Android staging switch
driver code
- dynamic debug updates
- printk rework, and /dev/kmsg changes
All of this has been tested in the linux-next releases for a few weeks
with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg Kroah-Hartman:
"Here's the driver core, and other driver subsystems, pull request for
the 3.5-rc1 merge window.
Outside of a few minor driver core changes, we ended up with the
following different subsystem and core changes as well, due to
interdependancies on the driver core:
- hyperv driver updates
- drivers/memory being created and some drivers moved into it
- extcon driver subsystem created out of the old Android staging
switch driver code
- dynamic debug updates
- printk rework, and /dev/kmsg changes
All of this has been tested in the linux-next releases for a few weeks
with no reported problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
Fix up conflicts in drivers/extcon/extcon-max8997.c where git noticed
that a patch to the deleted drivers/misc/max8997-muic.c driver needs to
be applied to this one.
* tag 'driver-core-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (90 commits)
uio_pdrv_genirq: get irq through platform resource if not set otherwise
memory: tegra{20,30}-mc: Remove empty *_remove()
printk() - isolate KERN_CONT users from ordinary complete lines
sysfs: get rid of some lockdep false positives
Drivers: hv: util: Properly handle version negotiations.
Drivers: hv: Get rid of an unnecessary check in vmbus_prep_negotiate_resp()
memory: tegra{20,30}-mc: Use dev_err_ratelimited()
driver core: Add dev_*_ratelimited() family
Driver Core: don't oops with unregistered driver in driver_find_device()
printk() - restore prefix/timestamp printing for multi-newline strings
printk: add stub for prepend_timestamp()
ARM: tegra30: Make MC optional in Kconfig
ARM: tegra20: Make MC optional in Kconfig
ARM: tegra30: MC: Remove unnecessary BUG*()
ARM: tegra20: MC: Remove unnecessary BUG*()
printk: correctly align __log_buf
ARM: tegra30: Add Tegra Memory Controller(MC) driver
ARM: tegra20: Add Tegra Memory Controller(MC) driver
printk() - restore timestamp printing at console output
printk() - do not merge continuation lines of different threads
...
guts of saved_sigmask-based sigsuspend/rt_sigsuspend. Takes
kernel sigset_t *.
Open-coded instances replaced with calling it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull core irq changes from Ingo Molnar:
"A collection of small fixes."
By Thomas Gleixner
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hexagon: Remove select of not longer existing Kconfig switches
arm: Select core options instead of redefining them
genirq: Do not consider disabled wakeup irqs
genirq: Allow check_wakeup_irqs to notice level-triggered interrupts
genirq: Be more informative on irq type mismatch
genirq: Reject bogus threaded irq requests
genirq: Streamline irq_action
Pull security subsystem updates from James Morris:
"New notable features:
- The seccomp work from Will Drewry
- PR_{GET,SET}_NO_NEW_PRIVS from Andy Lutomirski
- Longer security labels for Smack from Casey Schaufler
- Additional ptrace restriction modes for Yama by Kees Cook"
Fix up trivial context conflicts in arch/x86/Kconfig and include/linux/filter.h
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
apparmor: fix long path failure due to disconnected path
apparmor: fix profile lookup for unconfined
ima: fix filename hint to reflect script interpreter name
KEYS: Don't check for NULL key pointer in key_validate()
Smack: allow for significantly longer Smack labels v4
gfp flags for security_inode_alloc()?
Smack: recursive tramsmute
Yama: replace capable() with ns_capable()
TOMOYO: Accept manager programs which do not start with / .
KEYS: Add invalidation support
KEYS: Do LRU discard in full keyrings
KEYS: Permit in-place link replacement in keyring list
KEYS: Perform RCU synchronisation on keys prior to key destruction
KEYS: Announce key type (un)registration
KEYS: Reorganise keys Makefile
KEYS: Move the key config into security/keys/Kconfig
KEYS: Use the compat keyctl() syscall wrapper on Sparc64 for Sparc32 compat
Yama: remove an unused variable
samples/seccomp: fix dependencies on arch macros
Yama: add additional ptrace scopes
...
Pull smp hotplug cleanups from Thomas Gleixner:
"This series is merily a cleanup of code copied around in arch/* and
not changing any of the real cpu hotplug horrors yet. I wish I'd had
something more substantial for 3.5, but I underestimated the lurking
horror..."
Fix up trivial conflicts in arch/{arm,sparc,x86}/Kconfig and
arch/sparc/include/asm/thread_info_32.h
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits)
um: Remove leftover declaration of alloc_task_struct_node()
task_allocator: Use config switches instead of magic defines
sparc: Use common threadinfo allocator
score: Use common threadinfo allocator
sh-use-common-threadinfo-allocator
mn10300: Use common threadinfo allocator
powerpc: Use common threadinfo allocator
mips: Use common threadinfo allocator
hexagon: Use common threadinfo allocator
m32r: Use common threadinfo allocator
frv: Use common threadinfo allocator
cris: Use common threadinfo allocator
x86: Use common threadinfo allocator
c6x: Use common threadinfo allocator
fork: Provide kmemcache based thread_info allocator
tile: Use common threadinfo allocator
fork: Provide weak arch_release_[task_struct|thread_info] functions
fork: Move thread info gfp flags to header
fork: Remove the weak insanity
sh: Remove cpu_idle_wait()
...
Pull RCU changes from Ingo Molnar:
"This is the v3.5 RCU tree from Paul E. McKenney:
1) A set of improvements and fixes to the RCU_FAST_NO_HZ feature (with
more on the way for 3.6). Posted to LKML:
https://lkml.org/lkml/2012/4/23/324 (commits 1-3 and 5),
https://lkml.org/lkml/2012/4/16/611 (commit 4),
https://lkml.org/lkml/2012/4/30/390 (commit 6), and
https://lkml.org/lkml/2012/5/4/410 (commit 7, combined with
the other commits for the convenience of the tester).
2) Changes to make rcu_barrier() avoid disrupting execution of CPUs
that have no RCU callbacks. Posted to LKML:
https://lkml.org/lkml/2012/4/23/322.
3) A couple of commits that improve the efficiency of the interaction
between preemptible RCU and the scheduler, these two being all that
survived an abortive attempt to allow preemptible RCU's
__rcu_read_lock() to be inlined. The full set was posted to LKML at
https://lkml.org/lkml/2012/4/14/143, and the first and third patches
of that set remain.
4) Lai Jiangshan's algorithmic implementation of SRCU, which includes
call_srcu() and srcu_barrier(). A major feature of this new
implementation is that synchronize_srcu() no longer disturbs the
execution of other CPUs. This work is based on earlier
implementations by Peter Zijlstra and Paul E. McKenney. Posted to
LKML: https://lkml.org/lkml/2012/2/22/82.
5) A number of miscellaneous bug fixes and improvements which were
posted to LKML at: https://lkml.org/lkml/2012/4/23/353 with
subsequent updates posted to LKML."
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
rcu: Make rcu_barrier() less disruptive
rcu: Explicitly initialize RCU_FAST_NO_HZ per-CPU variables
rcu: Make RCU_FAST_NO_HZ handle timer migration
rcu: Update RCU maintainership
rcu: Make exit_rcu() more precise and consolidate
rcu: Move PREEMPT_RCU preemption to switch_to() invocation
rcu: Ensure that RCU_FAST_NO_HZ timers expire on correct CPU
rcu: Add rcutorture test for call_srcu()
rcu: Implement per-domain single-threaded call_srcu() state machine
rcu: Use single value to handle expedited SRCU grace periods
rcu: Improve srcu_readers_active_idx()'s cache locality
rcu: Remove unused srcu_barrier()
rcu: Implement a variant of Peter's SRCU algorithm
rcu: Improve SRCU's wait_idx() comments
rcu: Flip ->completed only once per SRCU grace period
rcu: Increment upper bit only for srcu_read_lock()
rcu: Remove fast check path from __synchronize_srcu()
rcu: Direct algorithmic SRCU implementation
rcu: Introduce rcutorture testing for rcu_barrier()
timer: Fix mod_timer_pinned() header comment
...
Pull core locking updates from Ingo Molnar:
"This update:
- extends and simplifies x86 NMI callback handling code to enhance
and fix the HP hw-watchdog driver
- simplifies the x86 NMI callback handling code to fix a kmemcheck
bug.
- enhances the hung-task debugger"
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/nmi: Fix the type of the nmiaction.flags field
x86/nmi: Fix page faults by nmiaction if kmemcheck is enabled
x86/nmi: Add new NMI queues to deal with IO_CHK and SERR
watchdog, hpwdt: Remove priority option for NMI callback
hung task debugging: Inject NMI when hung and going to panic
When repeating a UTC time value during a leap second (when the UTC
time should be 23:59:60), the TAI timescale should not stop. The kernel
NTP code increments the TAI offset one second too late. This patch fixes
the issue by incrementing the offset during the leap second itself.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Sigh, I missed to check which architecture Kconfig files actually
include the core Kconfig file. There are a few which did not. So we
broke them.
Instead of adding the includes to those, we are better off to move the
include to init/Kconfig like we did already with irqs and others.
This does not change anything for the architectures using the old
style periodic timer mode. It just solves the build wreckage there.
For those architectures which use the clock events infrastructure it
moves the include of the core Kconfig file to "General setup" which is
a way more logical place than having it at random locations specified
by the architecture specific Kconfigs.
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Anna-Maria Gleixner <anna-maria@glx-um.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As it's only user (UML) does no longer need it we can get
rid of it.
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
We really don't want all the arch code defining stuff
over and over.
[ anna-maria: Added missing GENERIC_CMOS_UPDATE switch ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@glx-um.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Link: http://lkml.kernel.org/r/1337529587.3208.2.camel@dionysos
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Fixes for perf/core:
- Rename some perf_target methods to avoid double negation, from Namhyung Kim.
- Revert change to use per task events with inheritance, from Namhyung Kim.
- Events should start disabled till children starts running, from David Ahern.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On 32bit builds gcc says:
kernel/user.c:30:4: warning: this decimal constant is unsigned only in ISO C90 [enabled by default]
kernel/user.c:38:4: warning: this decimal constant is unsigned only in ISO C90 [enabled by default]
Silence gcc by changing the constant 4294967295 to 4294967295U.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Convert to pr_fmt before things start to get out of hand and some
janitors start getting overly excited.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Presently irq_domain_simple_map() isn't labelled as static, but there's
no definition for it in the public irqdomain header either. At present
all in-tree ->map users have meaningful work to do, and all others are
using irq_domain_simple_ops directly. Make it static for now, as it can
always be exported and added to the public API later.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
modules making use of irq domains at the very least need access to the
add/remove/lookup routines, though there's nothing preventing them from
using the remainder of the public API, either.
The current set of exports seem primarily geared at DT-enabled platforms
using DT-backed IRQ domains, where many of the API accesses are hidden
away in OF code. The non-DT cases need to do most of this on their own.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Now that IRQ domains are being used by modules it's necessary to support
removing them, too. This adds a new irq_domain_remove() routine for doing
the bulk of the heavy lifting. It's left as an exercise to the caller to
ensure all mappings have been appropriatey disposed of before attempting
to remove the domain.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Make sure that the state of buffer_size_kb is initialized correctly and
returns actual size of the ring buffer.
Link: http://lkml.kernel.org/r/1336066834-1673-1-git-send-email-vnagarnaik@google.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
There are 2 separate loops to resize cpu buffers that are online and
offline. Merge them to make the code look better.
Also change the name from update_completion to update_done to allow
shorter lines.
Link: http://lkml.kernel.org/r/1337372991-14783-1-git-send-email-vnagarnaik@google.com
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Sometimes resume= parameter comes in integer style (e.g. major:minor)
and then name_to_dev_t can not detect partition properly. (especially
async device like usb, mmc).
This patch calls get_gendisk() if resumewait is true and resume_file
is in integer format to work around this problem.
Signed-off-by: Minho Ban <mhban@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Merge reason: We are going to queue up a dependent patch:
"perf tools: Move parse event automated tests to separated object"
That depends on:
commit e7c72d8
perf tools: Add 'G' and 'H' modifiers to event parsing
Conflicts:
tools/perf/builtin-stat.c
Conflicted with the recent 'perf_target' patches when checking the
result of perf_evsel open routines to see if a retry is needed to cope
with older kernels where the exclude guest/host perf_event_attr bits
were not used.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch moves kmsg_dump(KMSG_DUMP_PANIC) below smp_send_stop(),
to serialize the crash-logging process via smp_send_stop() and to
thus retrieve a more stable crash image of all CPUs stopped.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: dle-develop@lists.sourceforge.net <dle-develop@lists.sourceforge.net>
Cc: Satoru Moriya <satoru.moriya@hds.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: a.p.zijlstra@chello.nl <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/5C4C569E8A4B9B42A84A977CF070A35B2E4D7A5CE2@USINDEVS01.corp.hds.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Usually sleep-in-atomic bugs are followed by dozens other warnings.
This patch should help to figure out original source of problem.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120510122004.4873.12726.stgit@zurg
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit "userns: Convert setting and getting uid and gid system calls to use
kuid and kgid has modified the accessors in wait_task_continued() and
wait_task_stopped() to use __task_cred() instead of task_uid().
__task_cred() assumes that we're inside a rcu read lock, which is untrue
for these two functions.
Modify it to use task_uid() instead.
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Pull perf, x86 and scheduler updates from Ingo Molnar.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tracing: Do not enable function event with enable
perf stat: handle ENXIO error for perf_event_open
perf: Turn off compiler warnings for flex and bison generated files
perf stat: Fix case where guest/host monitoring is not supported by kernel
perf build-id: Fix filename size calculation
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, kvm: KVM paravirt kernels don't check for CPUID being unavailable
x86: Fix section annotation of acpi_map_cpu2node()
x86/microcode: Ensure that module is only loaded on supported Intel CPUs
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix KVM and ia64 boot crash due to sched_groups circular linked list assumption
It's been broken forever (i.e. it's not scheduling in a power
aware fashion), as reported by Suresh and others sending
patches, and nobody cares enough to fix it properly ...
so remove it to make space free for something better.
There's various problems with the code as it stands today, first
and foremost the user interface which is bound to topology
levels and has multiple values per level. This results in a
state explosion which the administrator or distro needs to
master and almost nobody does.
Furthermore large configuration state spaces aren't good, it
means the thing doesn't just work right because it's either
under so many impossibe to meet constraints, or even if
there's an achievable state workloads have to be aware of
it precisely and can never meet it for dynamic workloads.
So pushing this kind of decision to user-space was a bad idea
even with a single knob - it's exponentially worse with knobs
on every node of the topology.
There is a proposal to replace the user interface with a single
3 state knob:
sched_balance_policy := { performance, power, auto }
where 'auto' would be the preferred default which looks at things
like Battery/AC mode and possible cpufreq state or whatever the hw
exposes to show us power use expectations - but there's been no
progress on it in the past many months.
Aside from that, the actual implementation of the various knobs
is known to be broken. There have been sporadic attempts at
fixing things but these always stop short of reaching a mergable
state.
Therefore this wholesale removal with the hopes of spurring
people who care to come forward once again and work on a
coherent replacement.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1326104915.2442.53.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The function tracer will enable the -pg option with gcc, which requires
that frame pointers. When FRAME_POINTER is defined in the kernel config
it adds the gcc option -fno-omit-frame-pointer which causes some problems
on some architectures. For those architectures, the FRAME_POINTER select
was not set.
When FUNCTION_TRACER was selected on these architectures that can not have
-fno-omit-frame-pointer, the -pg option is still set. But when
FRAME_POINTER is not selected, the kernel config would add the gcc option
-fomit-frame-pointer. Adding this option is incompatible with -pg
even on archs that do not need frame pointers with -pg.
The answer to this was to just not add either -fno-omit-frame-pointer
or -fomit-frame-pointer on these archs that want function tracing
but do not set FRAME_POINTER.
As it turns out, for archs that require frame pointers for function
tracing, the same can be used. If gcc requires frame pointers with
-pg, it will simply add it. The best thing to do is not select FRAME_POINTER
when function tracing is selected, and let gcc add it if needed.
Only add the -fno-omit-frame-pointer when something else selects
FRAME_POINTER, but do not add -fomit-frame-pointer if function tracing
is selected.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
To remove duplicate code, have the ftrace arch_ftrace_update_code()
use the generic ftrace_modify_all_code(). This requires that the
default ftrace_replace_code() becomes a weak function so that an
arch may override it.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Rename __ftrace_modify_code() to ftrace_modify_all_code() and make
it global for all archs to use. This will remove the duplication
of code, as archs that can modify code without stop_machine()
can use it directly outside of the stop_machine() call.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
ftrace_location() is passed an addr, and returns 1 if the addr is
on a ftrace nop (or caller to ftrace_caller), and 0 otherwise.
To let kprobes know if it should move a breakpoint or not, it
must return the actual addr that is the start of the ftrace nop.
This way a kprobe placed on the location of a ftrace nop, can
instead be placed on the instruction after the nop. Even if the
probe addr is on the second or later byte of the nop, it can
simply be moved forward.
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Both ftrace_location() and ftrace_text_reserved() do basically the same thing.
They search to see if an address is in the ftace table (contains an address
that may change from nop to call ftrace_caller). The difference is
that ftrace_location() searches a single address, but ftrace_text_reserved()
searches a range.
This also makes the ftrace_text_reserved() faster as it now uses a bsearch()
instead of linearly searching all the addresses within a page.
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
As all records in a page of the ftrace table are sorted, we can
speed up the search algorithm by checking if the address to look for
falls in between the first and last record ip on the page.
This speeds up both the ftrace_location() and ftrace_text_reserved()
algorithms, as it can skip full pages when the search address is
not in them.
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The ftrace_record_ip() and ftrace_alloc_dyn_node() were from the
time of the ftrace daemon. Although they were still used, they
still make things a bit more complex than necessary.
Move the code into the one function that uses it, and remove the
helper functions.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Instead of just sorting the ip's of the functions per ftrace page,
sort the entire list before adding them to the ftrace pages.
This will allow the bsearch algorithm to be sped up as it can
also sort by pages, not just records within a page.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
According to Documentation/trace/ftrace.txt:
tracing_cpumask:
This is a mask that lets the user only trace
on specified CPUS. The format is a hex string
representing the CPUS.
The tracing_cpumask currently doesn't affect the tracing state of
per-CPU ring buffers.
This patch enables/disables CPU recording as its corresponding bit in
tracing_cpumask is set/unset.
Link: http://lkml.kernel.org/r/1336096792-25373-3-git-send-email-vnagarnaik@google.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
If tracing_dentry_percpu() failed, tracing_init_debugfs_percpu()
will try to create each cpu directories on debugfs' root directory
as d_percpu is NULL.
Link: http://lkml.kernel.org/r/1335143517-2285-1-git-send-email-namhyung.kim@lge.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When the ring buffer does its consistency test on itself, it
removes the head page, runs the tests, and then adds it back
to what the "head_page" pointer was. But because the head_page
pointer may lack behind the real head page (held by the link
list pointer). The reset may be incorrect.
Instead, if the head_page exists (it does not on first allocation)
reset it back to the real head page before running the consistency
tests. Then it will be put back to its original location after
the tests are complete.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
There use to be ring buffer integrity checks after updating the
size of the ring buffer. But now that the ring buffer can modify
the size while the system is running, the integrity checks were
removed, as they require the ring buffer to be disabed to perform
the check.
Move the integrity check to the reading of the ring buffer via the
iterator reads (the "trace" file). As reading via an iterator requires
disabling the ring buffer, it is a perfect place to have it.
If the ring buffer happens to be disabled when updating the size,
we still perform the integrity check.
Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Historical prepare_to_copy() is mostly a no-op, duplicated for majority of
the architectures and the rest following the x86 model of flushing the extended
register state like fpu there.
Remove it and use the arch_dup_task_struct() instead.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This patch adds the capability to add new pages to a ring buffer
atomically while write operations are going on. This makes it possible
to expand the ring buffer size without reinitializing the ring buffer.
The new pages are attached between the head page and its previous page.
Link: http://lkml.kernel.org/r/1336096792-25373-2-git-send-email-vnagarnaik@google.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch adds the capability to remove pages from a ring buffer
without destroying any existing data in it.
This is done by removing the pages after the tail page. This makes sure
that first all the empty pages in the ring buffer are removed. If the
head page is one in the list of pages to be removed, then the page after
the removed ones is made the head page. This removes the oldest data
from the ring buffer and keeps the latest data around to be read.
To do this in a non-racey manner, tracing is stopped for a very short
time while the pages to be removed are identified and unlinked from the
ring buffer. The pages are freed after the tracing is restarted to
minimize the time needed to stop tracing.
The context in which the pages from the per-cpu ring buffer are removed
runs on the respective CPU. This minimizes the events not traced to only
NMI trace contexts.
Link: http://lkml.kernel.org/r/1336096792-25373-1-git-send-email-vnagarnaik@google.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Justin Teravest <teravest@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
On gcc 4.5 the function tracing_mark_write() would give a warning
of page2 being uninitialized. This is due to a bug in gcc because
the logic prevents page2 from being used uninitialized, and
gcc 4.6+ does not complain (correctly).
Instead of adding a "unitialized" around page2, which could show
a bug later on, I combined page1 and page2 into an array map_pages[].
This binds the two and the two are modified according to nr_pages
(what gcc 4.5 seems to ignore). This no longer gives a warning with
gcc 4.5 nor with gcc 4.6.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
map_cred_ns is a light wrapper around from_kuid with the order of the arguments
reversed. Replace map_cred_ns with from_kuid and remove map_cred_ns.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Export handle_edge_irq() and irq_to_desc() to modules to allow them to
do things such as
__irq_set_handler_locked(...., handle_edge_irq);
This fixes
ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined!
ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined!
when gpio-pch is being built as a module.
This was introduced by commit df9541a60a ("gpio: pch9: Use proper flow
type handlers") that added
__irq_set_handler_locked(d->irq, handle_edge_irq);
but handle_edge_irq() was not exported for modules (and inlined
__irq_set_handler_locked() requires irq_to_desc() exported as well)
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Under memory load, on x86_64, with lockdep enabled, the workqueue's
process_one_work() has been seen to oops in __lock_acquire(), barfing
on a 0xffffffff00000000 pointer in the lockdep_map's class_cache[].
Because it's permissible to free a work_struct from its callout function,
the map used is an onstack copy of the map given in the work_struct: and
that copy is made without any locking.
Surprisingly, gcc (4.5.1 in Hugh's case) uses "rep movsl" rather than
"rep movsq" for that structure copy: which might race with a workqueue
user's wait_on_work() doing lock_map_acquire() on the source of the
copy, putting a pointer into the class_cache[], but only in time for
the top half of that pointer to be copied to the destination map.
Boom when process_one_work() subsequently does lock_map_acquire()
on its onstack copy of the lockdep_map.
Fix this, and a similar instance in call_timer_fn(), with a
lockdep_copy_map() function which additionally NULLs the class_cache[].
Note: this oops was actually seen on 3.4-next, where flush_work() newly
does the racing lock_map_acquire(); but Tejun points out that 3.4 and
earlier are already vulnerable to the same through wait_on_work().
* Patch orginally from Peter. Hugh modified it a bit and wrote the
description.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Hugh Dickins <hughd@google.com>
LKML-Reference: <alpine.LSU.2.00.1205070951170.1544@eggly.anvils>
Signed-off-by: Tejun Heo <tj@kernel.org>
* linus/master: (805 commits)
tty: Fix LED error return
openvswitch: checking wrong variable in queue_userspace_packet()
bonding: Fix LACPDU rx_dropped commit.
Linux 3.4-rc7
ARM: EXYNOS: fix ctrlbit for exynos5_clk_pdma1
ARM: EXYNOS: use s5p-timer for UniversalC210 board
ARM / mach-shmobile: Invalidate caches when booting secondary cores
ARM / mach-shmobile: sh73a0 SMP TWD boot regression fix
ARM / mach-shmobile: r8a7779 SMP TWD boot regression fix
ARM: mach-shmobile: convert ag5evm to use the generic MMC GPIO hotplug helper
ARM: mach-shmobile: convert mackerel to use the generic MMC GPIO hotplug helper
MAINTAINERS: Add myself as the cpufreq maintainer
dm mpath: check if scsi_dh module already loaded before trying to load
dm thin: correct module description
dm thin: fix unprotected use of prepared_discards list
dm thin: reinstate missing mempool_free in cell_release_singleton
gpio/exynos: Fix compiler warnings when non-exynos machines are selected
gpio: pch9: Use proper flow type handlers
powerpc/irq: Fix another case of lazy IRQ state getting out of sync
ks8851: Update link status during link change interrupt
...
Conflicts:
drivers/media/common/tuners/xc5000.c
drivers/media/common/tuners/xc5000.h
drivers/usb/gadget/uvc_queue.c
worker_enter_idle() has WARN_ON_ONCE() which triggers if nr_running
isn't zero when every worker is idle. This can trigger spuriously
while a cpu is going down due to the way trustee sets %WORKER_ROGUE
and zaps nr_running.
It first sets %WORKER_ROGUE on all workers without updating
nr_running, releases gcwq->lock, schedules, regrabs gcwq->lock and
then zaps nr_running. If the last running worker enters idle
inbetween, it would see stale nr_running which hasn't been zapped yet
and trigger the WARN_ON_ONCE().
Fix it by performing the sanity check iff the trustee is idle.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Arrange the continuation printk() buffering to be fully separated from the
ordinary full line users.
Limit the exposure to races and wrong printk() line merges to users of
continuation only. Ordinary full line users racing against continuation
users will no longer affect each other.
Multiple continuation users from different threads, racing against each
other will not wrongly be merged into a single line, but printed as
separate lines.
Test output of a kernel module which starts two separate threads which
race against each other, one of them printing a single full terminated
line:
printk("(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)\n");
The other one printing the line, every character separate in a
continuation loop:
printk("(C");
for (i = 0; i < 58; i++)
printk(KERN_CONT "C");
printk(KERN_CONT "C)\n");
Behavior of single and non-thread-aware printk() buffer:
# modprobe printk-race
printk test init
(CC(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
C(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
CC(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
C(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
CC(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
C(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
C(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
CC(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
C(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
C(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC)
(CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC)
New behavior with separate and thread-aware continuation buffer:
# modprobe printk-race
printk test init
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC)
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA)
(CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC)
(CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC)
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some numbers like nr_running and nr_uninterruptible are fundamentally
unsigned since its impossible to have a negative amount of tasks, yet
we still print them as signed to easily recognise the underflow
condition.
rq->nr_uninterruptible has 'special' accounting and can in fact very
easily become negative on a per-cpu basis.
It was noted that since the P() macro assumes things are long long and
the promotion of unsigned 'int/long' to long long on 32bit doesn't
sign extend we print silly large numbers instead of the easier to read
signed numbers.
Therefore extend the P() macro to not require the sign extention.
Reported-by: Diwakar Tundlam <dtundlam@nvidia.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-gk5tm8t2n4ix2vkpns42uqqp@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Group imbalance is meant to deal with situations where affinity masks
and sched domains don't align well, such as 3 cpus from one group and
6 from another. In this case the domain based balancer will want to
put an equal amount of tasks on each side even though they don't have
equal cpus.
Currently group_imb is set whenever two cpus of a group have a weight
difference of at least one avg task and the heaviest cpu has at least
two tasks. A group with imbalance set will always be picked as busiest
and a balance pass will be forced.
The problem is that even if there are no affinity masks this stuff can
trigger and cause weird balancing decisions, eg. the observed
behaviour was that of 6 cpus, 5 had 2 and 1 had 3 tasks, due to the
difference of 1 avg load (they all had the same weight) and nr_running
being >1 the group_imbalance logic triggered and did the weird thing
of pulling more load instead of trying to move the 1 excess task to
the other domain of 6 cpus that had 5 cpu with 2 tasks and 1 cpu with
1 task.
Curb the group_imbalance stuff by making the nr_running condition
weaker by also tracking the min_nr_running and using the difference in
nr_running over the set instead of the absolute max nr_running.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-9s7dedozxo8kjsb9kqlrukkf@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While investigating why the load-balancer did funny I found that the
rq->cpu_load[] tables were completely screwy.. a bit more digging
revealed that the updates that got through were missing ticks followed
by a catchup of 2 ticks.
The catchup assumes the cpu was idle during that time (since only nohz
can cause missed ticks and the machine is idle etc..) this means that
esp. the higher indices were significantly lower than they ought to
be.
The reason for this is that its not correct to compare against jiffies
on every jiffy on any other cpu than the cpu that updates jiffies.
This patch cludges around it by only doing the catch-up stuff from
nohz_idle_balance() and doing the regular stuff unconditionally from
the tick.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: pjt@google.com
Cc: Venkatesh Pallipadi <venki@google.com>
Link: http://lkml.kernel.org/n/tip-tp4kj18xdd5aj4vvj0qg55s2@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It's far too easy to get ridiculously large imbalance pct when you
scale it like that. Use a fixed 125% for now.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-zsriaft1dv7hhboyrpvqjy6s@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Patches c22402a2f ("sched/fair: Let minimally loaded cpu balance the
group") and 0ce90475 ("sched/fair: Add some serialization to the
sched_domain load-balance walk") are horribly broken so revert them.
The problem is that while it sounds good to have the minimally loaded
cpu do the pulling of more load, the way we walk the domains there is
absolutely no guarantee this cpu will actually get to the domain. In
fact its very likely it wont. Therefore the higher up the tree we get,
the less likely it is we'll balance at all.
The first of mask always walks up, while sucky in that it accumulates
load on the first cpu and needs extra passes to spread it out at least
guarantees a cpu gets up that far and load-balancing happens at all.
Since its now always the first and idle cpus should always be able to
balance so they get a task as fast as possible we can also do away
with the added serialization.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-rpuhs5s56aiv1aw7khv9zkw6@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's no need to convert a node number to a node number by
pretending its a cpu number..
Reported-by: Yinghai Lu <yinghai@kernel.org>
Reported-and-Tested-by: Greg Pearson <greg.pearson@hp.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-0sqhrht34phowgclj12dgk8h@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull the v3.5 RCU tree from Paul E. McKenney:
1) A set of improvements and fixes to the RCU_FAST_NO_HZ feature
(with more on the way for 3.6). Posted to LKML:
https://lkml.org/lkml/2012/4/23/324 (commits 1-3 and 5),
https://lkml.org/lkml/2012/4/16/611 (commit 4),
https://lkml.org/lkml/2012/4/30/390 (commit 6), and
https://lkml.org/lkml/2012/5/4/410 (commit 7, combined with
the other commits for the convenience of the tester).
2) Changes to make rcu_barrier() avoid disrupting execution of CPUs
that have no RCU callbacks. Posted to LKML:
https://lkml.org/lkml/2012/4/23/322.
3) A couple of commits that improve the efficiency of the interaction
between preemptible RCU and the scheduler, these two being all
that survived an abortive attempt to allow preemptible RCU's
__rcu_read_lock() to be inlined. The full set was posted to
LKML at https://lkml.org/lkml/2012/4/14/143, and the first and
third patches of that set remain.
4) Lai Jiangshan's algorithmic implementation of SRCU, which includes
call_srcu() and srcu_barrier(). A major feature of this new
implementation is that synchronize_srcu() no longer disturbs
the execution of other CPUs. This work is based on earlier
implementations by Peter Zijlstra and Paul E. McKenney. Posted to
LKML: https://lkml.org/lkml/2012/2/22/82.
5) A number of miscellaneous bug fixes and improvements which were
posted to LKML at: https://lkml.org/lkml/2012/4/23/353 with
subsequent updates posted to LKML.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a stub for prepend_timestamp() when CONFIG_PRINTK is not
enabled. Fixes this build error:
kernel/printk.c:1770:3: error: implicit declaration of function 'prepend_timestamp'
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make it possible to configure out the user space wakeup sources
garbage collector for debugging and default Android builds.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Arve Hjønnevåg <arve@android.com>
Make it possible to configure out the check against the limit of
user space wakeup sources for debugging and default Android builds.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Arve Hjønnevåg <arve@android.com>
barrier: Reduce the amount of disturbance by rcu_barrier() to the rest of
the system. This branch also includes improvements to
RCU_FAST_NO_HZ, which are included here due to conflicts.
fixes: Miscellaneous fixes.
inline: Remaining changes from an abortive attempt to inline
preemptible RCU's __rcu_read_lock(). These are (1) making
exit_rcu() avoid unnecessary work and (2) avoiding having
preemptible RCU record a blocked thread when the scheduler
declines to do a context switch.
srcu: Lai Jiangshan's algorithmic implementation of SRCU, including
call_srcu().
__log_buf must be aligned, because a 64-bit value is written directly
to it as part of struct log. Alignment of the log entries is typically
handled by log_store(), but this only triggers for subsequent entries,
not the very first (or wrapped) entries.
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fork() failure post namespace creation for a child cloned with
CLONE_NEWPID leaks pid_namespace/mnt_cache due to proc being mounted
during creation, but not unmounted during cleanup. Call
pid_ns_release_proc() during cleanup.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Louis Rilling <louis.rilling@kerlabs.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the adding of function tracing event to perf, it caused a
side effect that produces the following warning when enabling all
events in ftrace:
# echo 1 > /sys/kernel/debug/tracing/events/enable
[console]
event trace: Could not enable event function
This is because when enabling all events via the debugfs system
it ignores events that do not have a ->reg() function assigned.
This was to skip over the ftrace internal events (as they are
not TRACE_EVENTs). But as the ftrace function event now has
a ->reg() function attached to it for use with perf, it is no
longer ignored.
Worse yet, this ->reg() function is being called when it should
not be. It returns an error and causes the above warning to
be printed.
By adding a new event_call flag (TRACE_EVENT_FL_IGNORE_ENABLE)
and have all ftrace internel event structures have it set,
setting the events/enable will no longe try to incorrectly enable
the function event and does not warn.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
compat_sys_sigprocmask reads a smaller signal mask from userspace than
sigprogmask accepts for setting. So the high word of blocked.sig[0]
will be cleared, releasing any potentially blocked RT signal.
This was discovered via userspace code that relies on get/setcontext.
glibc's i386 versions of those functions use sigprogmask instead of
rt_sigprogmask to save/restore signal mask and caused RT signal
unblocking this way.
As suggested by Linus, this replaces the sys_sigprocmask based compat
version with one that open-codes the required logic, including the merge
of the existing blocked set with the new one provided on SIG_SETMASK.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The output of the timestamps got lost with the conversion of the
kmsg buffer to records; restore the old behavior.
Document, that CONFIG_PRINTK_TIME now only controls the output of
the timestamps in the syslog() system call and on the console, and
not the recording of the timestamps.
Cc: Joe Perches <joe@perches.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Sasha Levin <levinsasha928@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Reported-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This prevents the merging of printk() continuation lines of different
threads, in the case they race against each other.
It should properly isolate "atomic" single-line printk() users from
continuation users, to make sure the single-line users will never be
merged with the racy continuation ones.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The rcu_barrier() primitive interrupts each and every CPU, registering
a callback on every CPU. Once all of these callbacks have been invoked,
rcu_barrier() knows that every callback that was registered before
the call to rcu_barrier() has also been invoked.
However, there is no point in registering a callback on a CPU that
currently has no callbacks, most especially if that CPU is in a
deep idle state. This commit therefore makes rcu_barrier() avoid
interrupting CPUs that have no callbacks. Doing this requires reworking
the handling of orphaned callbacks, otherwise callbacks could slip through
rcu_barrier()'s net by being orphaned from a CPU that rcu_barrier() had
not yet interrupted to a CPU that rcu_barrier() had already interrupted.
This reworking was needed anyway to take a first step towards weaning
RCU from the CPU_DYING notifier's use of stop_cpu().
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current initialization of the RCU_FAST_NO_HZ per-CPU variables makes
needless and fragile assumptions about the initial value of things like
the jiffies counter. This commit therefore explicitly initializes all of
them that are better started with a non-zero value. It also adds some
comments describing the per-CPU state variables.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current RCU_FAST_NO_HZ assumes that timers do not migrate unless a
CPU goes offline, in which case it assumes that the CPU will have to come
out of dyntick-idle mode (cancelling the timer) in order to go offline.
This is important because when RCU_FAST_NO_HZ permits a CPU to enter
dyntick-idle mode despite having RCU callbacks pending, it posts a timer
on that CPU to force a wakeup on that CPU. This wakeup ensures that the
CPU will eventually handle the end of the grace period, including invoking
its RCU callbacks.
However, Pascal Chapperon's test setup shows that the timer handler
rcu_idle_gp_timer_func() really does get invoked in some cases. This is
problematic because this can cause the CPU that entered dyntick-idle
mode despite still having RCU callbacks pending to remain in
dyntick-idle mode indefinitely, which means that its RCU callbacks might
never be invoked. This situation can result in grace-period delays or
even system hangs, which matches Pascal's observations of slow boot-up
and shutdown (https://lkml.org/lkml/2012/4/5/142). See also the bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=806548
This commit therefore causes the "should never be invoked" timer handler
rcu_idle_gp_timer_func() to use smp_call_function_single() to wake up
the CPU for which the timer was intended, allowing that CPU to invoke
its RCU callbacks in a timely manner.
Reported-by: Pascal Chapperon <pascal.chapperon@wanadoo.fr>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
We can easily use a single callback for both sched-in and sched-out. This
reduces the code footprint in the scheduler path as well as removes
the PMU black spot otherwise present between the out and in callback.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-o56ajxp1edwqg6x9d31wb805@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We always need to pass the last sample period to
perf_sample_data_init(), otherwise the event distribution will be
wrong. Thus, modifiyng the function interface with the required period
as argument. So basically a pattern like this:
perf_sample_data_init(&data, ~0ULL);
data.period = event->hw.last_period;
will now be like that:
perf_sample_data_init(&data, ~0ULL, event->hw.last_period);
Avoids unininitialized data.period and simplifies code.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1333390758-10893-3-git-send-email-robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current code groups up to 16 nodes in a level and then puts an
ALLNODES domain spanning the entire tree on top of that. This doesn't
reflect the numa topology and esp for the smaller not-fully-connected
machines out there today this might make a difference.
Therefore, build a proper numa topology based on node_distance().
Since there's no fixed numa layers anymore, the static SD_NODE_INIT
and SD_ALLNODES_INIT aren't usable anymore, the new code tries to
construct something similar and scales some values either on the
number of cpus in the domain and/or the node_distance() ratio.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: linux-alpha@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-sh@vger.kernel.org
Cc: Matt Turner <mattst88@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: sparclinux@vger.kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86@kernel.org
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Greg Pearson <greg.pearson@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: bob.picco@oracle.com
Cc: chris.mason@oracle.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-r74n3n8hhuc2ynbrnp3vt954@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the sched_domain walk is completely unserialized (!SD_SERIALIZE)
it is possible that multiple cpus in the group get elected to do the
next level. Avoid this by adding some serialization.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-vqh9ai6s0ewmeakjz80w4qz6@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently we let the leftmost (or first idle) cpu ascend the
sched_domain tree and perform load-balancing. The result is that the
busiest cpu in the group might be performing this function and pull
more load to itself. The next load balance pass will then try to
equalize this again.
Change this to pick the least loaded cpu to perform higher domain
balancing.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-v8zlrmgmkne3bkcy9dej1fvm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since there's a PID space limit of 30bits (see
futex.h:FUTEX_TID_MASK) and allocating that many tasks (assuming a
lower bound of 2 pages per task) would still take 8T of memory it
seems reasonable to say that unsigned int is sufficient for
rq->nr_running.
When we do get anywhere near that amount of tasks I suspect other
things would go funny, load-balancer load computations would really
need to be hoisted to 128bit etc.
So save a few bytes and convert rq->nr_running and friends to
unsigned int.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-y3tvyszjdmbibade5bw8zl81@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we have one cpu that failed to boot and boot cpu gave up on
waiting for it and then another cpu is being booted, kernel
might crash with following OOPS:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
IP: [<ffffffff812c3630>] __bitmap_weight+0x30/0x80
Call Trace:
[<ffffffff8108b9b6>] build_sched_domains+0x7b6/0xa50
The crash happens in init_sched_groups_power() that expects
sched_groups to be circular linked list. However it is not
always true, since sched_groups preallocated in __sdt_alloc are
initialized in build_sched_groups and it may exit early
if (cpu != cpumask_first(sched_domain_span(sd)))
return 0;
without initializing sd->groups->next field.
Fix bug by initializing next field right after sched_group was
allocated.
Also-Reported-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Cc: a.p.zijlstra@chello.nl
Cc: pjt@google.com
Cc: seto.hidetoshi@jp.fujitsu.com
Link: http://lkml.kernel.org/r/1336559908-32533-1-git-send-email-imammedo@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The ftrace_disable_cpu() and ftrace_enable_cpu() functions were
needed back before the ring buffer was lockless. Now that the
ring buffer is lockless (and has been for some time), these functions
serve no purpose, and unnecessarily slow down operations of the tracer.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
It's appropriate to use __seq_open_private interface to open
some of trace seq files, because it covers all steps we are
duplicating in tracing code - zallocating the iterator and
setting it as seq_file's private.
Using this for following files:
trace
available_filter_functions
enabled_functions
Link: http://lkml.kernel.org/r/1335342219-2782-5-git-send-email-jolsa@redhat.com
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
[
Fixed warnings for:
kernel/trace/trace.c: In function '__tracing_open':
kernel/trace/trace.c:2418:11: warning: unused variable 'ret' [-Wunused-variable]
kernel/trace/trace.c:2417:19: warning: unused variable 'm' [-Wunused-variable]
]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
On Tue, May 8, 2012 at 10:02 AM, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> kernel/built-in.o: In function `devkmsg_read':
> printk.c:(.text+0x27e8): undefined reference to `__udivdi3'
> Most probably the "msg->ts_nsec / 1000" since
> ts_nsec is a u64 and this is a 32 bit build ...
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace __HAVE_ARCH_TASK_ALLOCATOR and __HAVE_ARCH_THREAD_ALLOCATOR
with proper config switches.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20120505150142.371309416@linutronix.de
Several architectures have their own kmemcache based thread allocator
because THREAD_SIZE is smaller than PAGE_SIZE. Add it to the core code
conditionally on THREAD_SIZE < PAGE_SIZE so the private copies can go.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120505150141.491002124@linutronix.de
These flags can be useful for extra allocations outside of the core
code.
Add __GFP_NOTRACK to them, so the archs which have kmemcheck do
not have to provide extra allocators just for that reason.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120505150141.428211694@linutronix.de
We error out when compiling with gcc4.1.[01] as it miscompiles
__weak. The workaround with magic defines is not longer
necessary. Make it __weak again.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120505150141.306358267@linutronix.de
Will replace the misnomed cpu_idle_wait() function which is copied a
gazillion times all over arch/*
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120507175652.049316594@linutronix.de
Support for multiple concurrent readers of /dev/kmsg, with read(),
seek(), poll() support. Output of message sequence numbers, to allow
userspace log consumers to reliably reconnect and reconstruct their
state at any given time. After open("/dev/kmsg"), read() always
returns *all* buffered records. If only future messages should be
read, SEEK_END can be used. In case records get overwritten while
/dev/kmsg is held open, or records get faster overwritten than they
are read, the next read() will return -EPIPE and the current reading
position gets updated to the next available record. The passed
sequence numbers allow the log consumer to calculate the amount of
lost messages.
[root@mop ~]# cat /dev/kmsg
5,0,0;Linux version 3.4.0-rc1+ (kay@mop) (gcc version 4.7.0 20120315 ...
6,159,423091;ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
7,160,424069;pci_root PNP0A03:00: host bridge window [io 0x0000-0x0cf7] (ignored)
SUBSYSTEM=acpi
DEVICE=+acpi:PNP0A03:00
6,339,5140900;NET: Registered protocol family 10
30,340,5690716;udevd[80]: starting version 181
6,341,6081421;FDC 0 is a S82078B
6,345,6154686;microcode: CPU0 sig=0x623, pf=0x0, revision=0x0
7,346,6156968;sr 1:0:0:0: Attached scsi CD-ROM sr0
SUBSYSTEM=scsi
DEVICE=+scsi:1:0:0:0
6,347,6289375;microcode: CPU1 sig=0x623, pf=0x0, revision=0x0
Cc: Karel Zak <kzak@redhat.com>
Tested-by: William Douglas <william.douglas@intel.com>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Record-based stream instead of the traditional byte stream
buffer. All records carry a 64 bit timestamp, the syslog facility
and priority in the record header.
- Records consume almost the same amount, sometimes less memory than
the traditional byte stream buffer (if printk_time is enabled). The record
header is 16 bytes long, plus some padding bytes at the end if needed.
The byte-stream buffer needed 3 chars for the syslog prefix, 15 char for
the timestamp and a newline.
- Buffer management is based on message sequence numbers. When records
need to be discarded, the reading heads move on to the next full
record. Unlike the byte-stream buffer, no old logged lines get
truncated or partly overwritten by new ones. Sequence numbers also
allow consumers of the log stream to get notified if any message in
the stream they are about to read gets discarded during the time
of reading.
- Better buffered IO support for KERN_CONT continuation lines, when printk()
is called multiple times for a single line. The use of KERN_CONT is now
mandatory to use continuation; a few places in the kernel need trivial fixes
here. The buffering could possibly be extended to per-cpu variables to allow
better thread-safety for multiple printk() invocations for a single line.
- Full-featured syslog facility value support. Different facilities
can tag their messages. All userspace-injected messages enforce a
facility value > 0 now, to be able to reliably distinguish them from
the kernel-generated messages. Independent subsystems like a
baseband processor running its own firmware, or a kernel-related
userspace process can use their own unique facility values. Multiple
independent log streams can co-exist that way in the same
buffer. All share the same global sequence number counter to ensure
proper ordering (and interleaving) and to allow the consumers of the
log to reliably correlate the events from different facilities.
Tested-by: William Douglas <william.douglas@intel.com>
Signed-off-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several distros set this by default by patching panic_on_oops.
It seems to fit with the BOOTPARAM_{HARD,SOFT}_PANIC options
though, so let's add a Kconfig entry and reduce some more
upstream delta.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120411121529.GH26688@redacted.bos.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implements trace_event support for uprobes. In its current form
it can be used to put probes at a specified offset in a file and
dump the required registers when the code flow reaches the
probed address.
The following example shows how to dump the instruction pointer
and %ax a register at the probed text address. Here we are
trying to probe zfree in /bin/zsh:
# cd /sys/kernel/debug/tracing/
# cat /proc/`pgrep zsh`/maps | grep /bin/zsh | grep r-xp
00400000-0048a000 r-xp 00000000 08:03 130904 /bin/zsh
# objdump -T /bin/zsh | grep -w zfree
0000000000446420 g DF .text 0000000000000012 Base
zfree # echo 'p /bin/zsh:0x46420 %ip %ax' > uprobe_events
# cat uprobe_events
p:uprobes/p_zsh_0x46420 /bin/zsh:0x0000000000046420
# echo 1 > events/uprobes/enable
# sleep 20
# echo 0 > events/uprobes/enable
# cat trace
# tracer: nop
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
zsh-24842 [006] 258544.995456: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79
zsh-24842 [007] 258545.000270: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79
zsh-24842 [002] 258545.043929: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79
zsh-24842 [004] 258547.046129: p_zsh_0x46420: (0x446420) arg1=446421 arg2=79
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120411103043.GB29437@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move parts of trace_kprobe.c that can be shared with upcoming
trace_uprobe.c. Common code to kernel/trace/trace_probe.h and
kernel/trace/trace_probe.c. There are no functional changes.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120409091144.8343.76218.sendpatchset@srdronam.in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
is_delete and is_return can take utmost 2 values and are better
of being a boolean than a int. There are no functional changes.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Anton Arapov <anton@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120409091133.8343.65289.sendpatchset@srdronam.in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The condition check in autosleep_store() is incorrect and prevents
/sys/power/autosleep from working as advertised. Fix that.
[rjw: Added the changelog.]
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
All archs define init_task in the same way (except ia64, but there is
no particular reason why ia64 cannot use the common version). Create a
generic instance so all archs can be converted over.
The config switch is temporary and will be removed when all archs are
converted over.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20120503085034.092585287@linutronix.de
I left 1 printk which uses __FILE__, __LINE__ explicitly, which should
not be subject to generic preferences expressed via pr_fmt().
+ tweaks suggested by Joe Perches:
- add doing to irq-enabled warning, like others. It wont happen often..
- change sysfs failure crit, not just err, make it 1 line in logs.
- coalese 2 format fragments into 1 >80 char line
cc: Joe Perches <joe@perches.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit 9fb48c744: "params: add 3rd arg to option handler callback
signature", the if-guard added to the pr_debug was overzealous; no
callers pass NULL, and existing code above and below the guard assumes
as much. Change the if-guard to match, and silence the Smack
complaint.
CC: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If an wakeup interrupt has been disabled before the suspend code
disables all interrupts then we have to ignore the pending flag.
Otherwise we would abort suspend over and over as nothing clears the
pending flag because the interrupt is disabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: NeilBrown <neilb@suse.de>
Level triggered interrupts do not cause IRQS_PENDING to be set when
they fire while "disabled" as the 'pending' state is always present in
the level - they automatically refire where re-enabled.
However the IRQS_PENDING flag is also used to abort a suspend cycle -
if any 'is_wakeup_set' interrupt is PENDING, check_wakeup_irqs() will
cause suspend to abort. Without IRQS_PENDING, suspend won't abort.
Consequently, level-triggered interrupts that fire during the 'noirq'
phase of suspend do not currently abort suspend.
So set IRQS_PENDING even for level triggered interrupts, and make sure
to clear the flag in check_irq_resend.
[ Changelog by courtesy of Neil ]
Tested-by: NeilBrown <neilb@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Merge tag 'v3.4-rc5' into next
Linux 3.4-rc5
Merge to pull in prerequisite change for Smack:
86812bb0de
Requested by Casey.
percpu areas are already allocated during boot for each possible cpu.
percpu idle threads can be considered as an extension of the percpu areas,
and allocate them for each possible cpu during boot.
This will eliminate the need for workqueue based idle thread allocation.
In future we can move the idle thread area into the percpu area too.
[ tglx: Moved the loop into smpboot.c and added an error check when
the init code failed to allocate an idle thread for a cpu which
should be onlined ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: venki@google.com
Link: http://lkml.kernel.org/r/1334966930.28674.245.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Update the permission checks to use the new uid_eq and gid_eq helpers
and remove the now unnecessary user_ns equality comparison.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Convert setregid, setgid, setreuid, setuid,
setresuid, getresuid, setresgid, getresgid, setfsuid, setfsgid,
getuid, geteuid, getgid, getegid,
waitpid, waitid, wait4.
Convert userspace uids and gids into kuids and kgids before
being placed on struct cred. Convert struct cred kuids and
kgids into userspace uids and gids when returning them.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
- Compare kuids with uid_eq
- kuid are uniuqe across all user namespaces so there is no longer the
need for a user_namespace comparison.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
These function are no longer needed replace them with their more useful equivalents.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
cred.h and a few trivial users of struct cred are changed. The rest of the users
of struct cred are left for other patches as there are too many changes to make
in one go and leave the change reviewable. If the user namespace is disabled and
CONFIG_UIDGID_STRICT_TYPE_CHECKS are disabled the code will contiue to compile
and behave correctly.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
As a first step to converting struct cred to be all kuid_t and kgid_t
values convert the group values stored in group_info to always be
kgid_t values. Unless user namespaces are used this change should
have no effect.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
When running preemptible RCU, if a task exits in an RCU read-side
critical section having blocked within that same RCU read-side critical
section, the task must be removed from the list of tasks blocking a
grace period (perhaps the current grace period, perhaps the next grace
period, depending on timing). The exit() path invokes exit_rcu() to
do this cleanup.
However, the current implementation of exit_rcu() needlessly does the
cleanup even if the task did not block within the current RCU read-side
critical section, which wastes time and needlessly increases the size
of the state space. Fix this by only doing the cleanup if the current
task is actually on the list of tasks blocking some grace period.
While we are at it, consolidate the two identical exit_rcu() functions
into a single function.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts:
kernel/rcupdate.c
Currently, PREEMPT_RCU readers are enqueued upon entry to the scheduler.
This is inefficient because enqueuing is required only if there is a
context switch, and entry to the scheduler does not guarantee a context
switch.
The commit therefore moves the enqueuing to immediately precede the
call to switch_to() from the scheduler.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
This was done to resolve a merge issue with the init/main.c file.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Android allows user space to manipulate wakelocks using two
sysfs file located in /sys/power/, wake_lock and wake_unlock.
Writing a wakelock name and optionally a timeout to the wake_lock
file causes the wakelock whose name was written to be acquired (it
is created before is necessary), optionally with the given timeout.
Writing the name of a wakelock to wake_unlock causes that wakelock
to be released.
Implement an analogous interface for user space using wakeup sources.
Add the /sys/power/wake_lock and /sys/power/wake_unlock files
allowing user space to create, activate and deactivate wakeup
sources, such that writing a name and optionally a timeout to
wake_lock causes the wakeup source of that name to be activated,
optionally with the given timeout. If that wakeup source doesn't
exist, it will be created and then activated. Writing a name to
wake_unlock causes the wakeup source of that name, if there is one,
to be deactivated. Wakeup sources created with the help of
wake_lock that haven't been used for more than 5 minutes are garbage
collected and destroyed. Moreover, there can be only WL_NUMBER_LIMIT
wakeup sources created with the help of wake_lock present at a time.
The data type used to track wakeup sources created by user space is
called "struct wakelock" to indicate the origins of this feature.
This version of the patch includes an rbtree manipulation fix from John Stultz.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Android uses one wakelock statistics that is only necessary for
opportunistic sleep. Namely, the prevent_suspend_time field
accumulates the total time the given wakelock has been locked
while "automatic suspend" was enabled. Add an analogous field,
prevent_sleep_time, to wakeup sources and make it behave in a similar
way.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introduce a mechanism by which the kernel can trigger global
transitions to a sleep state chosen by user space if there are no
active wakeup sources.
It consists of a new sysfs attribute, /sys/power/autosleep, that
can be written one of the strings returned by reads from
/sys/power/state, an ordered workqueue and a work item carrying out
the "suspend" operations. If a string representing the system's
sleep state is written to /sys/power/autosleep, the work item
triggering transitions to that state is queued up and it requeues
itself after every execution until user space writes "off" to
/sys/power/autosleep.
That work item enables the detection of wakeup events using the
functions already defined in drivers/base/power/wakeup.c (with one
small modification) and calls either pm_suspend(), or hibernate() to
put the system into a sleep state. If a wakeup event is reported
while the transition is in progress, it will abort the transition and
the "system suspend" work item will be queued up again.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NeilBrown <neilb@suse.de>
1. Do not allocate memory for buffers from emergency pools, unless
absolutely required. Do not warn about and do not retry non-essential
failed allocations.
2. Do not check the amount of free pages left on every single page
write, but wait until one map is completely populated and then check.
3. Set maximum number of pages for read buffering consistently, instead
of inadvertently depending on the size of the sector type.
4. Fix copyright line, which I missed when I submitted the hibernation
threading patch.
5. Dispense with bit shifting arithmetic to improve readability.
6. Really recalculate the number of pages required to be free after all
allocations have been done.
7. Fix calculation of pages required for read buffering. Only count in
pages that do not belong to high memory.
Signed-off-by: Bojan Smojver <bojan@rexursive.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Timers are subject to migration, which can lead to the following
system-hang scenario when CONFIG_RCU_FAST_NO_HZ=y:
1. CPU 0 executes synchronize_rcu(), which posts an RCU callback.
2. CPU 0 then goes idle. It cannot immediately invoke the callback,
but there is nothing RCU needs from ti, so it enters dyntick-idle
mode after posting a timer.
3. The timer gets migrated to CPU 1.
4. CPU 0 never wakes up, so the synchronize_rcu() never returns, so
the system hangs.
This commit fixes this problem by using mod_timer_pinned(), as suggested
by Peter Zijlstra, to ensure that the timer is actually posted on the
running CPU.
Reported-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
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Merge tag 'v3.4-rc5' into for-3.5/core
The core branch is behind driver commits that we want to build
on for 3.5, hence I'm pulling in a later -rc.
Linux 3.4-rc5
Conflicts:
Documentation/feature-removal-schedule.txt
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This introduces a fake module param $module.dyndbg. Its based upon
Thomas Renninger's $module.ddebug boot-time debugging patch from
https://lkml.org/lkml/2010/9/15/397
The 'fake' module parameter is provided for all modules, whether or
not they need it. It is not explicitly added to each module, but is
implemented in callbacks invoked from parse_args.
For builtin modules, dynamic_debug_init() now directly calls
parse_args(..., &ddebug_dyndbg_boot_params_cb), to process the params
undeclared in the modules, just after the ddebug tables are processed.
While its slightly weird to reprocess the boot params, parse_args() is
already called repeatedly by do_initcall_levels(). More importantly,
the dyndbg queries (given in ddebug_query or dyndbg params) cannot be
activated until after the ddebug tables are ready, and reusing
parse_args is cleaner than doing an ad-hoc parse. This reparse would
break options like inc_verbosity, but they probably should be params,
like verbosity=3.
ddebug_dyndbg_boot_params_cb() handles both bare dyndbg (aka:
ddebug_query) and module-prefixed dyndbg params, and ignores all other
parameters. For example, the following will enable pr_debug()s in 4
builtin modules, in the order given:
dyndbg="module params +p; module aio +p" module.dyndbg=+p pci.dyndbg
For loadable modules, parse_args() in load_module() calls
ddebug_dyndbg_module_params_cb(). This handles bare dyndbg params as
passed from modprobe, and errors on other unknown params.
Note that modprobe reads /proc/cmdline, so "modprobe foo" grabs all
foo.params, strips the "foo.", and passes these to the kernel.
ddebug_dyndbg_module_params_cb() is again called for the unknown
params; it handles dyndbg, and errors on others. The "doing" arg
added previously contains the module name.
For non CONFIG_DYNAMIC_DEBUG builds, the stub function accepts
and ignores $module.dyndbg params, other unknowns get -ENOENT.
If no param value is given (as in pci.dyndbg example above), "+p" is
assumed, which enables all pr_debug callsites in the module.
The dyndbg fake parameter is not shown in /sys/module/*/parameters,
thus it does not use any resources. Changes to it are made via the
control file.
Also change pr_info in ddebug_exec_queries to vpr_info,
no need to see it all the time.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
CC: Thomas Renninger <trenn@suse.de>
CC: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a 3rd arg, named "doing", to unknown-options callbacks invoked
from parse_args(). The arg is passed as:
"Booting kernel" from start_kernel(),
initcall_level_names[i] from do_initcall_level(),
mod->name from load_module(), via parse_args(), parse_one()
parse_args() already has the "name" parameter, which is renamed to
"doing" to better reflect current uses 1,2 above. parse_args() passes
it to an altered parse_one(), which now passes it down into the
unknown option handler callbacks.
The mod->name will be needed to handle dyndbg for loadable modules,
since params passed by modprobe are not qualified (they do not have a
"$modname." prefix), and by the time the unknown-param callback is
called, the module name is not otherwise available.
Minor tweaks:
Add param-name to parse_one's pr_debug(), current message doesnt
identify the param being handled, add it.
Add a pr_info to print current level and level_name of the initcall,
and number of registered initcalls at that level. This adds 7 lines
to dmesg output, like:
initlevel:6=device, 172 registered initcalls
Drop "parameters" from initcall_level_names[], its unhelpful in the
pr_info() added above. This array is passed into parse_args() by
do_initcall_level().
CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add srcu_torture_deferred_free() for srcu_ops so as to test the new
call_srcu(). Rename the original srcu_ops to srcu_sync_ops.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit implements an SRCU state machine in support of call_srcu().
The state machine is preemptible, light-weight, and single-threaded,
minimizing synchronization overhead. In particular, there is no longer
any need for synchronize_srcu() to be guarded by a mutex.
Expedited processing is handled, at least in the absence of concurrent
grace-period operations on that same srcu_struct structure, by having
the synchronize_srcu_expedited() thread take on the role of the
workqueue thread for one iteration.
There is a reasonable probability that a given SRCU callback will
be invoked on the same CPU that registered it, however, there is no
guarantee. Concurrent SRCU grace-period primitives can cause callbacks
to be executed elsewhere, even in absence of CPU-hotplug operations.
Callbacks execute in process context, but under the influence of
local_bh_disable(), so it is illegal to sleep in an SRCU callback
function.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The earlier algorithm used an "expedited" flag combined with a "trycount"
counter to differentiate between normal and expedited SRCU grace periods.
However, the difference can be encoded into a single counter with a cutoff
value and different initial values for expedited and normal SRCU grace
periods. This commit makes that change.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Conflicts:
kernel/srcu.c
Expand the calls to srcu_readers_active_idx() from srcu_readers_active()
inline. This change improves cache locality by interating over the CPUs
once rather than twice.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit implements a variant of Peter's algorithm, which may be found
at https://lkml.org/lkml/2012/2/1/119.
o Make the checking lock-free to enable parallel checking.
Parallel checking is required when (1) the original checking
task is preempted for a long time, (2) sychronize_srcu_expedited()
starts during an ongoing SRCU grace period, or (3) we wish to
avoid acquiring a lock.
o Since the checking is lock-free, we avoid a mutex in state machine
for call_srcu().
o Remove the SRCU_REF_MASK and remove the coupling with the flipping.
This might allow us to remove the preempt_disable() in future
versions, though such removal will need great care because it
rescinds the one-old-reader-per-CPU guarantee.
o Remove a smp_mb(), simplify the comments and make the smp_mb() pairs
more intuitive.
Inspired-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The safety of SRCU is provided byy wait_idx() rather than flipping.
The flipping actually prevents starvation.
This commit therefore updates the comments to more accurately and
precisely describe what is going on.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This is an optimization of the SRCU grace period. To guard against
preempted readers with old values of the counter, it suffices to scan the
old counters once more, then flip ->completed only one time. The reason
this works is that the old readers must have incremented the old set of
counters (if they have not yet incremented, then their critical section
starts after this grace period, so they may be safely ignored).
This commit therefore optimizes the second flip out in favor of a simple
rescan.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The purpose of the upper bit of SRCU's per-CPU counters is to guarantee
that no reasonable series of srcu_read_lock() and srcu_read_unlock()
operations can return the value of the counter to its original value.
This guarantee is require only after the index has been switched to
the other set of counters, so at most one srcu_read_lock() can affect
a given CPU's counter. The number of srcu_read_unlock() operations
on a given counter is limited to the number of tasks in the system,
which given the Linux kernel's current structure is limited to far less
than 2^30 on 32-bit systems and far less than 2^62 on 64-bit systems.
(Something about a limited number of bytes in the kernel's address space.)
Therefore, if srcu_read_lock() increments the upper bits, then
srcu_read_unlock() need not do so. In this case, an srcu_read_lock() and
an srcu_read_unlock() will flip the lower bit of the upper field of the
counter. An unreasonably large additional number of srcu_read_unlock()
operations would be required to return the counter to its initial value,
thus preserving the guarantee.
This commit takes this approach, which further allows it to shrink
the size of the upper field to one bit, making the number of
srcu_read_unlock() operations required to return the counter to its
initial value even more unreasonable than before.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The fastpath in __synchronize_srcu() is designed to handle cases where
there are a large number of concurrent calls for the same srcu_struct
structure. However, the Linux kernel currently does not use SRCU in
this manner, so remove the fastpath checks for simplicity.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The current implementation of synchronize_srcu_expedited() can cause
severe OS jitter due to its use of synchronize_sched(), which in turn
invokes try_stop_cpus(), which causes each CPU to be sent an IPI.
This can result in severe performance degradation for real-time workloads
and especially for short-interation-length HPC workloads. Furthermore,
because only one instance of try_stop_cpus() can be making forward progress
at a given time, only one instance of synchronize_srcu_expedited() can
make forward progress at a time, even if they are all operating on
distinct srcu_struct structures.
This commit, inspired by an earlier implementation by Peter Zijlstra
(https://lkml.org/lkml/2012/1/31/211) and by further offline discussions,
takes a strictly algorithmic bits-in-memory approach. This has the
disadvantage of requiring one explicit memory-barrier instruction in
each of srcu_read_lock() and srcu_read_unlock(), but on the other hand
completely dispenses with OS jitter and furthermore allows SRCU to be
used freely by CPUs that RCU believes to be idle or offline.
The update-side implementation handles the single read-side memory
barrier by rechecking the per-CPU counters after summing them and
by running through the update-side state machine twice.
This implementation has passed moderate rcutorture testing on both
x86 and Power. Also updated to use this_cpu_ptr() instead of per_cpu_ptr(),
as suggested by Peter Zijlstra.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Although rcutorture does invoke rcu_barrier() and friends, it cannot
really be called a torture test given that it invokes them only once
at the end of the test. This commit therefore introduces heavy-duty
rcutorture testing for rcu_barrier(), which may be carried out
concurrently with normal rcutorture testing.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Fix for an issue causing hibernation to hang on systems with highmem (that
practically means i386) due to broken memory management (bug introduced in 3.2,
so -stable material) and PM documentation update making the freezer
documentation follow the code again after some recent updates.
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Merge tag 'pm-for-3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael J. Wysocki:
"Fix for an issue causing hibernation to hang on systems with highmem
(that practically means i386) due to broken memory management (bug
introduced in 3.2, so -stable material) and PM documentation update
making the freezer documentation follow the code again after some
recent updates."
* tag 'pm-for-3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / Freezer / Docs: Update documentation about freezing of tasks
PM / Hibernate: fix the number of pages used for hibernate/thaw buffering
Pull perf fixes from Ingo Molnar.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix perf_event_for_each() to use sibling
perf symbols: Read plt symbols from proper symtab_type binary
tracing: Fix stacktrace of latency tracers (irqsoff and friends)
perf tools: Add 'G' and 'H' modifiers to event parsing
tracing: Fix regression with tracing_on
perf tools: Drop CROSS_COMPILE from flex and bison calls
perf report: Fix crash showing warning related to kernel maps
tracing: Fix build breakage without CONFIG_PERF_EVENTS (again)
Pull build fixes for less mainstream architectures from Paul Gortmaker:
"These are fixes for frv(1), blackfin(2), powerpc(1) and xtensa(4).
Fortunately the touches are nearly all specific to files just used by
the arch in question. The two touches to shared/common files
[kernel/irq/debug.h and drivers/pci/Makefile] are trivial to assess as
no risk to anyone.
Half of them relate to xtensa directly. It was only when I fixed the
last xtensa issue that I realized that the arch has been broken for a
significant time, and isn't a specific v3.4 regression. So if you
wanted, we could leave xtensa lying bleeding in the street for a
couple more weeks and queue those for 3.5. But given they are no risk
to anyone outside of xtensa, I figured to just leave them in.
If you are OK with taking the xtensa fixes, then please pull to get:
- one last implicit include uncovered by system.h that is in a file
specific to just one powerpc defconfig. (I'd sync'd with BenH).
- fix an oversight in the PCI makefile where shared code wasn't being
compiled for ARCH=frv
- fix a missing include for GPIO in blackfin framebuffer.
- audit and tag endif in blackfin ezkit board file, in order to find
and fix the misplaced endif masking a block of code.
- fix irq/debug.h choice of temporary macro names to be more internal
so they don't conflict with names used by xtensa.
- fix a reference to an undeclared local var in xtensa's signal.c
- fix an implicit bug.h usage in xtensa's asm/io.h uncovered by my
removing bug.h from kernel.h
- fix xtensa to properly indicate it is using asm-generic/hardirq.h
in order to resolve the link error - undefined ack_bad_irq
The xtensa still fails final link as my latest binutils does something
evil when ld forward-relocates unlikely() blocks, but in theory people
who have older/valid toolchains could now use the thing."
* 'for-v3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
xtensa: fix build fail on undefined ack_bad_irq
blackfin: fix ifdef fustercluck in mach-bf538/boards/ezkit.c
blackfin: fix compile error in bfin-lq035q1-fb.c
pci: frv architecture needs generic setup-bus infrastructure
irq: hide debug macros so they don't collide with others.
xtensa: fix build error in xtensa/include/asm/io.h
xtensa: fix build failure in xtensa/kernel/signal.c
powerpc: fix system.h fallout in sysdev/scom.c [chroma_defconfig]
Updating max_usage is something one would expect when we reach
a new maximum usage value even when we do this by forcing through
the limit with res_counter_charge_nofail().
(Whether we want to account failcnt when we force through the limit
is another debate).
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Glauber Costa <glommer@parallels.com>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Li Zefan <lizefan@huawei.com>
These two functions do almost the same thing and duplicate some code.
Merge their implementation into a single common function.
res_counter_charge_locked() takes one more parameter but it doesn't seem
to be used outside res_counter.c yet anyway.
There is no (intended) change in the behaviour.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Glauber Costa <glommer@parallels.com>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Li Zefan <lizefan@huawei.com>
The mod_timer_pinned() header comment states that it prevents timers
from being migrated to a different CPU. This is not the case, instead,
it ensures that the timer is posted to the current CPU, but does nothing
to prevent CPU-hotplug operations from migrating the timer.
This commit therefore brings the comment header into alignment with
reality.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
RCU_FAST_NO_HZ uses a timer to limit the time that a CPU with callbacks
can remain in dyntick-idle mode. This timer is cancelled when the CPU
exits idle, and therefore should never fire. However, if the timer
were migrated to some other CPU for whatever reason (1) the timer could
actually fire and (2) firing on some other CPU would fail to wake up the
CPU with callbacks, possibly resulting in sluggishness or a system hang.
This commit therfore adds a WARN_ON_ONCE() to the timer handler in order
to detect this condition.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
In perf_event_for_each() we call a function on an event, and then
iterate over the siblings of the event.
However we don't call the function on the siblings, we call it
repeatedly on the original event - it seems "obvious" that we should
be calling it with sibling as the argument.
It looks like this broke in commit 75f937f24b ("Fix ctx->mutex
vs counter->mutex inversion").
The only effect of the bug is that the PERF_IOC_FLAG_GROUP parameter
to the ioctls doesn't work.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1334109253-31329-1-git-send-email-michael@ellerman.id.au
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Under extreme memory used up situations, percpu allocation
might fail. We hit it when system goes to suspend-to-ram,
causing a kworker panic:
EIP: [<c124411a>] build_sched_domains+0x23a/0xad0
Kernel panic - not syncing: Fatal exception
Pid: 3026, comm: kworker/u:3
3.0.8-137473-gf42fbef #1
Call Trace:
[<c18cc4f2>] panic+0x66/0x16c
[...]
[<c1244c37>] partition_sched_domains+0x287/0x4b0
[<c12a77be>] cpuset_update_active_cpus+0x1fe/0x210
[<c123712d>] cpuset_cpu_inactive+0x1d/0x30
[...]
With this fix applied build_sched_domains() will return -ENOMEM and
the suspend attempt fails.
Signed-off-by: he, bo <bo.he@intel.com>
Reviewed-by: Zhang, Yanmin <yanmin.zhang@intel.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1335355161.5892.17.camel@hebo
[ So, we fail to deallocate a CPU because we cannot allocate RAM :-/
I don't like that kind of sad behavior but nevertheless it should
not crash under high memory load. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commits 367456c756 ("sched: Ditch per cgroup task lists for
load-balancing") and 5d6523ebd ("sched: Fix load-balance wreckage")
left some more wreckage.
By setting loop_max unconditionally to ->nr_running load-balancing
could take a lot of time on very long runqueues (hackbench!). So keep
the sysctl as max limit of the amount of tasks we'll iterate.
Furthermore, the min load filter for migration completely fails with
cgroups since inequality in per-cpu state can easily lead to such
small loads :/
Furthermore the change to add new tasks to the tail of the queue
instead of the head seems to have some effect.. not quite sure I
understand why.
Combined these fixes solve the huge hackbench regression reported by
Tim when hackbench is ran in a cgroup.
Reported-by: Tim Chen <tim.c.chen@linux.intel.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1335365763.28150.267.camel@twins
[ got rid of the CONFIG_PREEMPT tuning and made small readability edits ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
All SMP architectures have magic to fork the idle task and to store it
for reusage when cpu hotplug is enabled. Provide a generic
infrastructure for it.
Create/reinit the idle thread for the cpu which is brought up in the
generic code and hand the thread pointer to the architecture code via
__cpu_up().
Note, that fork_idle() is called via a workqueue, because this
guarantees that the idle thread does not get a reference to a user
space VM. This can happen when the boot process did not bring up all
possible cpus and a later cpu_up() is initiated via the sysfs
interface. In that case fork_idle() would be called in the context of
the user space task and take a reference on the user space VM.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Acked-by: Venkatesh Pallipadi <venki@google.com>
Link: http://lkml.kernel.org/r/20120420124557.102478630@linutronix.de
Start a new file, which will hold SMP and CPU hotplug related generic
infrastructure.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124557.035417523@linutronix.de
Preparatory patch to make the idle thread allocation for secondary
cpus generic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
- Convert the old uid mapping functions into compatibility wrappers
- Add a uid/gid mapping layer from user space uid and gids to kernel
internal uids and gids that is extent based for simplicty and speed.
* Working with number space after mapping uids/gids into their kernel
internal version adds only mapping complexity over what we have today,
leaving the kernel code easy to understand and test.
- Add proc files /proc/self/uid_map /proc/self/gid_map
These files display the mapping and allow a mapping to be added
if a mapping does not exist.
- Allow entering the user namespace without a uid or gid mapping.
Since we are starting with an existing user our uids and gids
still have global mappings so are still valid and useful they just don't
have local mappings. The requirement for things to work are global uid
and gid so it is odd but perfectly fine not to have a local uid
and gid mapping.
Not requiring global uid and gid mappings greatly simplifies
the logic of setting up the uid and gid mappings by allowing
the mappings to be set after the namespace is created which makes the
slight weirdness worth it.
- Make the mappings in the initial user namespace to the global
uid/gid space explicit. Today it is an identity mapping
but in the future we may want to twist this for debugging, similar
to what we do with jiffies.
- Document the memory ordering requirements of setting the uid and
gid mappings. We only allow the mappings to be set once
and there are no pointers involved so the requirments are
trivial but a little atypical.
Performance:
In this scheme for the permission checks the performance is expected to
stay the same as the actuall machine instructions should remain the same.
The worst case I could think of is ls -l on a large directory where
all of the stat results need to be translated with from kuids and
kgids to uids and gids. So I benchmarked that case on my laptop
with a dual core hyperthread Intel i5-2520M cpu with 3M of cpu cache.
My benchmark consisted of going to single user mode where nothing else
was running. On an ext4 filesystem opening 1,000,000 files and looping
through all of the files 1000 times and calling fstat on the
individuals files. This was to ensure I was benchmarking stat times
where the inodes were in the kernels cache, but the inode values were
not in the processors cache. My results:
v3.4-rc1: ~= 156ns (unmodified v3.4-rc1 with user namespace support disabled)
v3.4-rc1-userns-: ~= 155ns (v3.4-rc1 with my user namespace patches and user namespace support disabled)
v3.4-rc1-userns+: ~= 164ns (v3.4-rc1 with my user namespace patches and user namespace support enabled)
All of the configurations ran in roughly 120ns when I performed tests
that ran in the cpu cache.
So in summary the performance impact is:
1ns improvement in the worst case with user namespace support compiled out.
8ns aka 5% slowdown in the worst case with user namespace support compiled in.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
- Transform userns->creator from a user_struct reference to a simple
kuid_t, kgid_t pair.
In cap_capable this allows the check to see if we are the creator of
a namespace to become the classic suser style euid permission check.
This allows us to remove the need for a struct cred in the mapping
functions and still be able to dispaly the user namespace creators
uid and gid as 0.
- Remove the now unnecessary delayed_work in free_user_ns.
All that is left for free_user_ns to do is to call kmem_cache_free
and put_user_ns. Those functions can be called in any context
so call them directly from free_user_ns removing the need for delayed work.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Send an NMI to all CPUs when a hung task is detected and the hung
task code is configured to panic. This gives us a fairly uptodate
snapshot of all CPUs in the system.
This lets us get stack trace of all CPUs which makes life easier
trying to debug a deadlock, and the NMI doesn't change anything
since the next step is a kernel panic.
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1331848040-1676-1-git-send-email-levinsasha928@gmail.com
[ extended the changelog a bit ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The rcutorture initialization code ignored the error returns from
rcu_torture_onoff_init() and rcu_torture_stall_init(). The rcutorture
cleanup code failed to NULL out a number of pointers. These bugs will
normally have no effect, but this commit fixes them nevertheless.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Both Steven Rostedt's new idle-capable trace macros and the RCU_NONIDLE()
macro can cause RCU to momentarily pause out of idle without the rest
of the system being involved. This can cause rcu_prepare_for_idle()
to run through its state machine too quickly, which can in turn result
in needless scheduling-clock interrupts.
This commit therefore adds code to enable rcu_prepare_for_idle() to
distinguish between an initial entry to idle on the one hand (which needs
to advance the rcu_prepare_for_idle() state machine) and an idle reentry
due to idle-capable trace macros and RCU_NONIDLE() on the other hand
(which should avoid advancing the rcu_prepare_for_idle() state machine).
Additional state is maintained to allow the timer to be correctly reposted
when returning after a momentary pause out of idle, and even more state
is maintained to detect when new non-lazy callbacks have been enqueued
(which may require re-evaluation of the approach to idleness).
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The RCU_FAST_NO_HZ facility uses an hrtimer to wake up a CPU when
it is allowed to go into dyntick-idle mode, which is almost always
cancelled soon after. This is not what hrtimers are good at, so
this commit switches to the timer wheel.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Traces of rcu_prep_idle events can be confusing because
rcu_cleanup_after_idle() does no tracing. This commit therefore adds
this tracing.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcu_blocking_is_gp() function tests to see if there is only one
online CPU, and if so, synchronize_sched() and friends become no-ops.
However, for larger systems, num_online_cpus() scans a large vector,
and might be preempted while doing so. While preempted, any number
of CPUs might come online and go offline, potentially resulting in
num_online_cpus() returning 1 when there never had only been one
CPU online. This could result in a too-short RCU grace period, which
could in turn result in total failure, except that the only way that
the grace period is too short is if there is an RCU read-side critical
section spanning it. For RCU-sched and RCU-bh (which are the only
cases using rcu_blocking_is_gp()), RCU read-side critical sections
have either preemption or bh disabled, which prevents CPUs from going
offline. This in turn prevents actual failures from occurring.
This commit therefore adds a large block comment to rcu_blocking_is_gp()
documenting why it is safe. This commit also moves rcu_blocking_is_gp()
into kernel/rcutree.c, which should help prevent unwary developers from
mistaking it for a generally useful function.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Commit #0209f649 (rcu: limit rcu_node leaf-level fanout) set an upper
limit of 16 on the leaf-level fanout for the rcu_node tree. This was
needed to reduce lock contention that was induced by the synchronization
of scheduling-clock interrupts, which was in turn needed to improve
energy efficiency for moderate-sized lightly loaded servers.
However, reducing the leaf-level fanout means that there are more
leaf-level rcu_node structures in the tree, which in turn means that
RCU's grace-period initialization incurs more cache misses. This is
not a problem on moderate-sized servers with only a few tens of CPUs,
but becomes a major source of real-time latency spikes on systems with
many hundreds of CPUs. In addition, the workloads running on these large
systems tend to be CPU-bound, which eliminates the energy-efficiency
advantages of synchronizing scheduling-clock interrupts. Therefore,
these systems need maximal values for the rcu_node leaf-level fanout.
This commit addresses this problem by introducing a new kernel parameter
named RCU_FANOUT_LEAF that directly controls the leaf-level fanout.
This parameter defaults to 16 to handle the common case of a moderate
sized lightly loaded servers, but may be set higher on larger systems.
Reported-by: Mike Galbraith <efault@gmx.de>
Reported-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Hibernation regression fix, since 3.2.
Calculate the number of required free pages based on non-high memory
pages only, because that is where the buffers will come from.
Commit 081a9d043c introduced a new buffer
page allocation logic during hibernation, in order to improve the
performance. The amount of pages allocated was calculated based on total
amount of pages available, although only non-high memory pages are
usable for this purpose. This caused hibernation code to attempt to over
allocate pages on platforms that have high memory, which led to hangs.
Signed-off-by: Bojan Smojver <bojan@rexursive.com>
Signed-off-by: Rafael J. Wysocki <rjw@suse.de>
Add a debugfs entry under per_cpu/ folder for each cpu called
buffer_size_kb to control the ring buffer size for each CPU
independently.
If the global file buffer_size_kb is used to set size, the individual
ring buffers will be adjusted to the given size. The buffer_size_kb will
report the common size to maintain backward compatibility.
If the buffer_size_kb file under the per_cpu/ directory is used to
change buffer size for a specific CPU, only the size of the respective
ring buffer is updated. When tracing/buffer_size_kb is read, it reports
'X' to indicate that sizes of per_cpu ring buffers are not equivalent.
Link: http://lkml.kernel.org/r/1328212844-11889-1-git-send-email-vnagarnaik@google.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: Justin Teravest <teravest@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Linus Torvalds
Ingo Molnar
Tim Bird
Oleg Nesterov
Steven Rostedt
Jiri Olsa
David Howells
Thomas Gleixner
Al Viro
Richard Cochran
Richard Weinberger
Eric W. Biederman
Mark Brown
Paul Mundt
Vaibhav Nagarnaik
Minho Ban
Arnaldo Carvalho de Melo
Seiji Aguchi
Konstantin Khlebnikov
Sasha Levin
Peter Zijlstra
Namhyung Kim
Suresh Siddha
Jiri Kosina
Mauro Carvalho Chehab
Tejun Heo
Kay Sievers
Peter Zijlstra
Randy Dunlap
Rafael J. Wysocki
Paul E. McKenney
Stephen Warren
Mike Galbraith
Jan Kiszka
Paul E. McKenney
Robert Richter
Igor Mammedov
Hiroshi Shimamoto
Kyle McMartin
Srikar Dronamraju
Arve Hjønnevåg
Jim Cromie
James Morris
Greg Kroah-Hartman
Bojan Smojver
Jens Axboe
Lai Jiangshan
Frederic Weisbecker
Michael Ellerman
he, bo