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  1. 15 3月, 2014 6 次提交
  3. 14 3月, 2014 1 次提交
    • D
      perf tools: Fix synthesizing mmaps for threads · bfd66cc7
      由 Don Zickus 提交于 
      Currently if a process creates a bunch of threads using pthread_create
and then perf is run in system_wide mode, the mmaps for those threads
are not captured with a synthesized mmap event.

The reason is those threads are not visible when walking the /proc/
directory looking for /proc/<pid>/maps files.  Instead they are
discovered using the /proc/<pid>/tasks file (which the synthesized comm
event uses).

This causes problems when a program is trying to map a data address to a
tid.  Because the tid has no maps, the event is dropped.  Changing the
program to look up using the pid instead of the tid, finds the correct
maps but creates ugly hacks in the program to carry the correct tid
around.

Fix this by moving the walking of the /proc/<pid>/tasks up a level (out
of the comm function) based on Arnaldo's suggestion.

Tweaked things a bit to special case the 'full' bit and 'guest' check.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1393429527-167840-2-git-send-email-dzickus@redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      bfd66cc7
  5. 11 3月, 2014 1 次提交
  7. 10 3月, 2014 2 次提交
  9. 28 2月, 2014 1 次提交
    • J
      perf tools: Fix strict alias issue for find_first_bit · b39c2a57
      由 Jiri Olsa 提交于 
      When compiling perf tool code with gcc 4.4.7 I'm getting
following error:

    CC       util/session.o
  cc1: warnings being treated as errors
  util/session.c: In function ‘perf_session_deliver_event’:
  tools/perf/util/include/linux/bitops.h:109: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  tools/perf/util/include/linux/bitops.h:101: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  util/session.c:697: note: initialized from here
  tools/perf/util/include/linux/bitops.h:101: note: initialized from here
  make[1]: *** [util/session.o] Error 1
  make: *** [util/session.o] Error 2

The aliased types here are u64 and unsigned long pointers, which is safe
for the find_first_bit processing.

This error shows up for me only for gcc 4.4 on 32bit x86, even for
-Wstrict-aliasing=3, while newer gcc are quiet and scream here for
-Wstrict-aliasing={2,1}. Looks like newer gcc changed the rules for
strict alias warnings.

The gcc documentation offers workaround for valid aliasing by using
__may_alias__ attribute:

  http://gcc.gnu.org/onlinedocs/gcc-4.4.0/gcc/Type-Attributes.html

Using this workaround for the find_first_bit function.
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1393434867-20271-1-git-send-email-jolsa@redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b39c2a57
  11. 25 2月, 2014 2 次提交
  13. 24 2月, 2014 3 次提交
  15. 18 2月, 2014 24 次提交