Commit Graph

16 Commits

Author SHA1 Message Date
Steven Rostedt (Red Hat) d2b0191a38 tracing/probes: Do not use return value of trace_seq_printf()
The functions trace_seq_printf() and friends will soon not have a return
value and will only be a void function. Use trace_seq_has_overflowed()
instead to know if the trace_seq operations succeeded or not.

Link: http://lkml.kernel.org/r/20141114011411.530216306@goodmis.org

Reviewed-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-19 15:25:44 -05:00
Masami Hiramatsu 3da0f18007 kprobes, ftrace: Use NOKPROBE_SYMBOL macro in ftrace
Use NOKPROBE_SYMBOL macro to protect functions from
kprobes instead of __kprobes annotation in ftrace.
This applies nokprobe_inline annotation for some cases,
because NOKPROBE_SYMBOL() will inhibit inlining by
referring the symbol address.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140417081828.26341.55152.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:26:39 +02:00
Masami Hiramatsu fbc1963d2c kprobes, ftrace: Allow probing on some functions
There is no need to prohibit probing on the functions
used for preparation and uprobe only fetch functions.
Those are safely probed because those are not invoked
from kprobe's breakpoint/fault/debug handlers. So there
is no chance to cause recursive exceptions.

Following functions are now removed from the kprobes blacklist:

	update_bitfield_fetch_param
	free_bitfield_fetch_param
	kprobe_register
	FETCH_FUNC_NAME(stack, type) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, type) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, string) in trace_uprobe.c
	FETCH_FUNC_NAME(memory, string_size) in trace_uprobe.c
	FETCH_FUNC_NAME(file_offset, type) in trace_uprobe.c

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140417081800.26341.56504.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:03:02 +02:00
Namhyung Kim b7e0bf341f tracing/uprobes: Add @+file_offset fetch method
Enable to fetch data from a file offset.  Currently it only supports
fetching from same binary uprobe set.  It'll translate the file offset
to a proper virtual address in the process.

The syntax is "@+OFFSET" as it does similar to normal memory fetching
(@ADDR) which does no address translation.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 20:57:05 -05:00
Namhyung Kim b079d374fd tracing/uprobes: Add support for full argument access methods
Enable to fetch other types of argument for the uprobes.  IOW, we can
access stack, memory, deref, bitfield and retval from uprobes now.

The format for the argument types are same as kprobes (but @SYMBOL
type is not supported for uprobes), i.e:

  @ADDR   : Fetch memory at ADDR
  $stackN : Fetch Nth entry of stack (N >= 0)
  $stack  : Fetch stack address
  $retval : Fetch return value
  +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address

Note that the retval only can be used with uretprobes.

Original-patch-by: Hyeoncheol Lee <cheol.lee@lge.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Hyeoncheol Lee <cheol.lee@lge.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 20:56:21 -05:00
Namhyung Kim 5baaa59ef0 tracing/probes: Implement 'memory' fetch method for uprobes
Use separate method to fetch from memory.  Move existing functions to
trace_kprobe.c and make them static.  Also add new memory fetch
implementation for uprobes.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:43 -05:00
Hyeoncheol Lee 3925f4a5af tracing/probes: Add fetch{,_size} member into deref fetch method
The deref fetch methods access a memory region but it assumes that
it's a kernel memory since uprobes does not support them.

Add ->fetch and ->fetch_size member in order to provide a proper
access methods for supporting uprobes.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Hyeoncheol Lee <cheol.lee@lge.com>
[namhyung@kernel.org: Split original patch into pieces as requested]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:42 -05:00
Namhyung Kim 1301a44e77 tracing/probes: Move 'symbol' fetch method to kprobes
Move existing functions to trace_kprobe.c and add NULL entries to the
uprobes fetch type table.  I don't make them static since some generic
routines like update/free_XXX_fetch_param() require pointers to the
functions.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:41 -05:00
Namhyung Kim 3fd996a295 tracing/probes: Implement 'stack' fetch method for uprobes
Use separate method to fetch from stack.  Move existing functions to
trace_kprobe.c and make them static.  Also add new stack fetch
implementation for uprobes.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:40 -05:00
Namhyung Kim 34fee3a104 tracing/probes: Split [ku]probes_fetch_type_table
Use separate fetch_type_table for kprobes and uprobes.  It currently
shares all fetch methods but some of them will be implemented
differently later.

This is not to break build if [ku]probes is configured alone (like
!CONFIG_KPROBE_EVENT and CONFIG_UPROBE_EVENT).  So I added '__weak'
to the table declaration so that it can be safely omitted when it
configured out.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:39 -05:00
Namhyung Kim b26c74e116 tracing/probes: Move fetch function helpers to trace_probe.h
Move fetch function helper macros/functions to the header file and
make them external.  This is preparation of supporting uprobe fetch
table in next patch.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:38 -05:00
Namhyung Kim 5bf652aaf4 tracing/probes: Integrate duplicate set_print_fmt()
The set_print_fmt() functions are implemented almost same for
[ku]probes.  Move it to a common place and get rid of the duplication.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:38 -05:00
Namhyung Kim 50eb2672ce tracing/probes: Fix basic print type functions
The print format of s32 type was "ld" and it's casted to "long".  So
it turned out to print 4294967295 for "-1" on 64-bit systems.  Not
sure whether it worked well on 32-bit systems.

Anyway, it doesn't need to have cast argument at all since it already
casted using type pointer - just get rid of it.  Thanks to Oleg for
pointing that out.

And print 0x prefix for unsigned type as it shows hex numbers.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2014-01-02 16:17:24 -05:00
Daniel Walter bcd83ea6cb tracing: Replace strict_strto* with kstrto*
* remove old string conversions with kstrto*

Link: http://lkml.kernel.org/r/20120926200838.GC1244@0x90.at

Signed-off-by: Daniel Walter <sahne@0x90.at>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-10-31 16:45:23 -04:00
Srikar Dronamraju f3f096cfed tracing: Provide trace events interface for uprobes
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>
2012-05-07 14:30:17 +02:00
Srikar Dronamraju 8ab83f5647 tracing: Extract out common code for kprobes/uprobes trace events
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>
2012-05-07 14:29:57 +02:00