1. 26 9月, 2014 1 次提交
    • A
      perf evlist: Introduce perf_evlist__filter_pollfd method · 1ddec7f0
      Arnaldo Carvalho de Melo 提交于
      To remove all entries in evlist->pollfd[] that have revents matching at
      least one of the bits in the specified mask.
      
      It'll adjust evlist->nr_fds to the number of unfiltered fds and will
      return this value, as a convenience and to avoid requiring direct access
      to internal state of perf_evlist objects.
      
      This will be used after polling the evlist fds so that we remove fds
      that were closed by the kernel.
      Acked-by: NJiri Olsa <jolsa@kernel.org>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Don Zickus <dzickus@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Namhyung Kim <namhyung@kernel.org>
      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-y2sca7z3wicvvy40a50lozwm@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      1ddec7f0
  2. 14 8月, 2014 2 次提交
  3. 13 1月, 2014 3 次提交
  4. 20 12月, 2013 1 次提交
  5. 13 12月, 2013 2 次提交
  6. 13 11月, 2013 1 次提交
  7. 06 11月, 2013 3 次提交
  8. 29 10月, 2013 1 次提交
  9. 18 10月, 2013 2 次提交
    • A
      perf trace: Improve messages related to /proc/sys/kernel/perf_event_paranoid · a8f23d8f
      Arnaldo Carvalho de Melo 提交于
      kernel/events/core.c has:
      
        /*
         * perf event paranoia level:
         *  -1 - not paranoid at all
         *   0 - disallow raw tracepoint access for unpriv
         *   1 - disallow cpu events for unpriv
         *   2 - disallow kernel profiling for unpriv
         */
        int sysctl_perf_event_paranoid __read_mostly = 1;
      
      So, with the default being 1, a non-root user can trace his stuff:
      
        [acme@zoo ~]$ cat /proc/sys/kernel/perf_event_paranoid
        1
        [acme@zoo ~]$ yes > /dev/null &
        [1] 15338
        [acme@zoo ~]$ trace -p 15338 | head -5
             0.005 ( 0.005 ms): write(fd: 1</dev/null>, buf: 0x7fe6db765000, count: 4096 ) = 4096
             0.045 ( 0.001 ms): write(fd: 1</dev/null>, buf: 0x7fe6db765000, count: 4096 ) = 4096
             0.085 ( 0.001 ms): write(fd: 1</dev/null>, buf: 0x7fe6db765000, count: 4096 ) = 4096
             0.125 ( 0.001 ms): write(fd: 1</dev/null>, buf: 0x7fe6db765000, count: 4096 ) = 4096
             0.165 ( 0.001 ms): write(fd: 1</dev/null>, buf: 0x7fe6db765000, count: 4096 ) = 4096
        [acme@zoo ~]$
        [acme@zoo ~]$ trace --duration 1 sleep 1
          1002.148 (1001.218 ms): nanosleep(rqtp: 0x7fff46c79250                           ) = 0
        [acme@zoo ~]$
        [acme@zoo ~]$ trace -- usleep 1 | tail -5
             0.905 ( 0.002 ms): brk(                                                     ) = 0x1c82000
             0.910 ( 0.003 ms): brk(brk: 0x1ca3000                                       ) = 0x1ca3000
             0.913 ( 0.001 ms): brk(                                                     ) = 0x1ca3000
             0.990 ( 0.059 ms): nanosleep(rqtp: 0x7fffe31a3280                           ) = 0
             0.995 ( 0.000 ms): exit_group(
        [acme@zoo ~]$
      
      But can't do system wide tracing:
      
        [acme@zoo ~]$ trace
        Error:	Operation not permitted.
        Hint:	Check /proc/sys/kernel/perf_event_paranoid setting.
        Hint:	For system wide tracing it needs to be set to -1.
        Hint:	The current value is 1.
        [acme@zoo ~]$
      
        [acme@zoo ~]$ trace --cpu 0
        Error:	Operation not permitted.
        Hint:	Check /proc/sys/kernel/perf_event_paranoid setting.
        Hint:	For system wide tracing it needs to be set to -1.
        Hint:	The current value is 1.
        [acme@zoo ~]$
      
      If the paranoid level is >= 2, i.e. turn this perf stuff off for !root users:
      
        [acme@zoo ~]$ sudo sh -c 'echo 2 > /proc/sys/kernel/perf_event_paranoid'
        [acme@zoo ~]$ cat /proc/sys/kernel/perf_event_paranoid
        2
        [acme@zoo ~]$
        [acme@zoo ~]$ trace usleep 1
        Error:	Permission denied.
        Hint:	Check /proc/sys/kernel/perf_event_paranoid setting.
        Hint:	For your workloads it needs to be <= 1
        Hint:	For system wide tracing it needs to be set to -1.
        Hint:	The current value is 2.
        [acme@zoo ~]$
        [acme@zoo ~]$ trace
        Error:	Permission denied.
        Hint:	Check /proc/sys/kernel/perf_event_paranoid setting.
        Hint:	For your workloads it needs to be <= 1
        Hint:	For system wide tracing it needs to be set to -1.
        Hint:	The current value is 2.
        [acme@zoo ~]$
        [acme@zoo ~]$ trace --cpu 1
        Error:	Permission denied.
        Hint:	Check /proc/sys/kernel/perf_event_paranoid setting.
        Hint:	For your workloads it needs to be <= 1
        Hint:	For system wide tracing it needs to be set to -1.
        Hint:	The current value is 2.
        [acme@zoo ~]$
      
      If the user manages to get what he/she wants, convincing root not
      to be paranoid at all...
      
        [root@zoo ~]# echo -1 > /proc/sys/kernel/perf_event_paranoid
        [root@zoo ~]# cat /proc/sys/kernel/perf_event_paranoid
        -1
        [root@zoo ~]#
      
        [acme@zoo ~]$ ps -eo user,pid,comm | grep Xorg
        root       729 Xorg
        [acme@zoo ~]$
        [acme@zoo ~]$ trace -a --duration 0.001 -e \!select,ioctl,writev | grep Xorg  | head -5
            23.143 ( 0.003 ms): Xorg/729 setitimer(which: REAL, value: 0x7fffaadf16e0 ) = 0
            23.152 ( 0.004 ms): Xorg/729 read(fd: 31, buf: 0x2544af0, count: 4096     ) = 8
            23.161 ( 0.002 ms): Xorg/729 read(fd: 31, buf: 0x2544af0, count: 4096     ) = -1 EAGAIN Resource temporarily unavailable
            23.175 ( 0.002 ms): Xorg/729 setitimer(which: REAL, value: 0x7fffaadf16e0 ) = 0
            23.235 ( 0.002 ms): Xorg/729 setitimer(which: REAL, value: 0x7fffaadf16e0 ) = 0
        [acme@zoo ~]$
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mike Galbraith <efault@gmx.de>
      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-di28olfwd28rvkox7v3hqhu1@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a8f23d8f
    • A
      perf evlist: Introduce perf_evlist__strerror_tp method · 6ef068cb
      Arnaldo Carvalho de Melo 提交于
      Out of 'perf trace', should be used by other tools that uses
      tracepoints.
      
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ramkumar Ramachandra <artagnon@gmail.com>
      Cc: Stephane Eranian <eranian@google.com>
      Link: http://lkml.kernel.org/n/tip-lyvtxhchz4ga8fwht15x8wou@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      6ef068cb
  10. 11 10月, 2013 1 次提交
    • J
      perf evlist: Fix perf_evlist__mmap_read event overflow · a65cb4b9
      Jiri Olsa 提交于
      The perf_evlist__mmap_read used 'union perf_event' as a placeholder for
      event crossing the mmap boundary.
      
      This is ok for sample shorter than ~PATH_MAX. However we could grow up
      to the maximum sample size which is 16 bits max.
      
      I hit this overflow issue when using 'perf top -G dwarf' which produces
      sample with the size around 8192 bytes.  We could configure any valid
      sample size here using: '-G dwarf,size'.
      
      Using array with sample max size instead for the event placeholder. Also
      adding another safe check for the dynamic size of the user stack.
      
      TODO: The 'struct perf_mmap' is quite big now, maybe we could use some
      lazy allocation for event_copy size.
      Signed-off-by: NJiri Olsa <jolsa@redhat.com>
      Acked-by: NDavid Ahern <dsahern@gmail.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/1380721599-24285-1-git-send-email-jolsa@redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a65cb4b9
  11. 09 10月, 2013 2 次提交
  12. 03 9月, 2013 1 次提交
  13. 30 8月, 2013 2 次提交
  14. 08 8月, 2013 2 次提交
  15. 16 3月, 2013 5 次提交
  16. 07 2月, 2013 1 次提交
    • D
      perf evlist: Make event_copy local to mmaps · 0479b8b9
      David Ahern 提交于
      I am getting segfaults *after* the time sorting of perf samples where
      the event type is off the charts:
      
      (gdb) bt
      \#0  0x0807b1b2 in hists__inc_nr_events (hists=0x80a99c4, type=1163281902) at util/hist.c:1225
      \#1  0x08070795 in perf_session_deliver_event (session=0x80a9b90, event=0xf7a6aff8, sample=0xffffc318, tool=0xffffc520,
          file_offset=0) at util/session.c:884
      \#2  0x0806f9b9 in flush_sample_queue (s=0x80a9b90, tool=0xffffc520) at util/session.c:555
      \#3  0x0806fc53 in process_finished_round (tool=0xffffc520, event=0x0, session=0x80a9b90) at util/session.c:645
      
      This is bizarre because the event has already been processed once --
      before it was added to the samples queue -- and the event was found to
      be sane at that time.
      
      There seem to be 2 causes:
      
      1. perf_evlist__mmap_read updates the read location even though there
      are outstanding references to events sitting in the mmap buffers via the
      ordered samples queue.
      
      2. There is a single evlist->event_copy for all evlist entries.
      event_copy is used to handle an event wrapping at the mmap buffer
      boundary.
      
      This patch addresses the second problem - making event_copy local to
      each perf_mmap. With this change my highly repeatable use case no longer
      fails.
      
      The first problem is much more complicated and will be the subject of a
      future patch.
      Signed-off-by: NDavid Ahern <dsahern@gmail.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1360098762-61827-1-git-send-email-dsahern@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      0479b8b9
  17. 01 2月, 2013 1 次提交
  18. 12 12月, 2012 1 次提交
  19. 03 10月, 2012 2 次提交
  20. 27 9月, 2012 2 次提交
  21. 26 9月, 2012 1 次提交
  22. 07 9月, 2012 1 次提交
  23. 15 8月, 2012 2 次提交