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  1. 22 10月, 2013 1 次提交
  3. 10 10月, 2013 5 次提交
  5. 04 10月, 2013 2 次提交
  7. 23 7月, 2013 1 次提交
  9. 13 7月, 2013 2 次提交
  11. 28 5月, 2013 6 次提交
  13. 01 4月, 2013 3 次提交
  15. 07 2月, 2013 3 次提交
  17. 30 1月, 2013 1 次提交
  19. 25 1月, 2013 7 次提交
  21. 17 10月, 2012 2 次提交
  23. 18 9月, 2012 1 次提交
  25. 11 9月, 2012 1 次提交
    • I
      perf tools: Use __maybe_used for unused variables · 1d037ca1
      由 Irina Tirdea 提交于 
      perf defines both __used and __unused variables to use for marking
unused variables. The variable __used is defined to
__attribute__((__unused__)), which contradicts the kernel definition to
__attribute__((__used__)) for new gcc versions. On Android, __used is
also defined in system headers and this leads to warnings like: warning:
'__used__' attribute ignored

__unused is not defined in the kernel and is not a standard definition.
If __unused is included everywhere instead of __used, this leads to
conflicts with glibc headers, since glibc has a variables with this name
in its headers.

The best approach is to use __maybe_unused, the definition used in the
kernel for __attribute__((unused)). In this way there is only one
definition in perf sources (instead of 2 definitions that point to the
same thing: __used and __unused) and it works on both Linux and Android.
This patch simply replaces all instances of __used and __unused with
__maybe_unused.
Signed-off-by: NIrina Tirdea <irina.tirdea@intel.com>
Acked-by: NPekka Enberg <penberg@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1347315303-29906-7-git-send-email-irina.tirdea@intel.com
[ committer note: fixed up conflict with a116e05d in builtin-sched.c ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      1d037ca1
  27. 08 9月, 2012 1 次提交
  29. 20 6月, 2012 1 次提交
    • A
      perf tools: Add sort by src line/number · 409a8be6
      由 Arnaldo Carvalho de Melo 提交于 
      Using addr2line for now, requires debuginfo, needs more work to support
detached debuginfo, aka foo-debuginfo packages.

Example:

	[root@sandy ~]# perf record -a sleep 3
	[ perf record: Woken up 1 times to write data ]
	[ perf record: Captured and wrote 0.555 MB perf.data (~24236 samples) ]
	[root@sandy ~]# perf report -s dso,srcline 2>&1 | grep -v ^# | head -5
	    22.41%  [kernel.kallsyms]  /home/git/linux/drivers/idle/intel_idle.c:280
	     4.79%  [kernel.kallsyms]  /home/git/linux/drivers/cpuidle/cpuidle.c:148
	     4.78%  [kernel.kallsyms]  /home/git/linux/arch/x86/include/asm/atomic64_64.h:121
	     4.49%  [kernel.kallsyms]  /home/git/linux/kernel/sched/core.c:1690
	     4.30%  [kernel.kallsyms]  /home/git/linux/include/linux/seqlock.h:90
	[root@sandy ~]#

[root@sandy ~]# perf top -U -s dso,symbol,srcline
Samples: 1K of event 'cycles', Event count (approx.): 589617389
 18.66%  [kernel]  [k] copy_user_generic_unrolled   /home/git/linux/arch/x86/lib/copy_user_64.S:143
  7.83%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:39
  6.59%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:38
  3.66%  [kernel]  [k] page_fault                   /home/git/linux/arch/x86/kernel/entry_64.S:1379
  3.25%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:40
  3.12%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:37
  2.74%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:36
  2.39%  [kernel]  [k] clear_page                   /home/git/linux/arch/x86/lib/clear_page_64.S:43
  2.12%  [kernel]  [k] ioread32                     /home/git/linux/lib/iomap.c:90
  1.51%  [kernel]  [k] copy_user_generic_unrolled   /home/git/linux/arch/x86/lib/copy_user_64.S:144
  1.19%  [kernel]  [k] copy_user_generic_unrolled   /home/git/linux/arch/x86/lib/copy_user_64.S:154
Suggested-by: NAndi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-pdmqbng9twz06jzkbgtuwbp8@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      409a8be6
  31. 14 3月, 2012 1 次提交
    • A
      perf tools: Incorrect use of snprintf results in SEGV · b832796c
      由 Anton Blanchard 提交于 
      I have a workload where perf top scribbles over the stack and we SEGV.
What makes it interesting is that an snprintf is causing this.

The workload is a c++ gem that has method names over 3000 characters
long, but snprintf is designed to avoid overrunning buffers. So what
went wrong?

The problem is we assume snprintf returns the number of characters
written:

    ret += repsep_snprintf(bf + ret, size - ret, "[%c] ", self->level);
...
    ret += repsep_snprintf(bf + ret, size - ret, "%s", self->ms.sym->name);

Unfortunately this is not how snprintf works. snprintf returns the
number of characters that would have been written if there was enough
space. In the above case, if the first snprintf returns a value larger
than size, we pass a negative size into the second snprintf and happily
scribble over the stack. If you have 3000 character c++ methods thats a
lot of stack to trample.

This patch fixes repsep_snprintf by clamping the value at size - 1 which
is the maximum snprintf can write before adding the NULL terminator.

I get the sinking feeling that there are a lot of other uses of snprintf
that have this same bug, we should audit them all.

Cc: David Ahern <dsahern@gmail.com>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/20120307114249.44275ca3@krytenSigned-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b832796c
  33. 09 3月, 2012 2 次提交