1. 17 9月, 2015 1 次提交
    • S
      perf stat: Fix per-pkg event reporting bug · 02d8dabc
      Stephane Eranian 提交于
      Per-pkg events need to be captured once per processor socket. The code
      in check_per_pkg() ensures only one value per processor package is used.
      However there is a problem with this function in case the first CPU of
      the package does not measure anything for the per-pkg event, but other
      CPUs do.
      
      Consider the following:
      
        $ create cgroup FOO; echo $$ >FOO/tasks; taskset -c 1 noploop &
        $ perf stat -a -I 1000 -e intel_cqm/llc_occupancy/ -G FOO sleep 100
          1.00000 <not counted> Bytes intel_cqm/llc_occupancy/  FOO
      
      The reason for this is that CPU0 in the cgroup has nothing running on it.
      Yet check_per_plg() will mark socket0 as processed and no other event
      value will be considered for the socket.
      
      This patch fixes the problem by having check_per_pkg() only consider
      events which actually ran.
      Signed-off-by: NStephane Eranian <eranian@google.com>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kan Liang <kan.liang@intel.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1441286620-10117-1-git-send-email-eranian@google.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      02d8dabc
  2. 15 9月, 2015 15 次提交
  3. 13 9月, 2015 1 次提交
    • A
      perf header: Fixup reading of HEADER_NRCPUS feature · caa47047
      Arnaldo Carvalho de Melo 提交于
      The original patch introducing this header wrote the number of CPUs available
      and online in one order and then swapped those values when reading, fix it.
      
      Before:
      
        # perf record usleep 1
        # perf report --header-only | grep 'nrcpus \(online\|avail\)'
        # nrcpus online : 4
        # nrcpus avail : 4
        # echo 0 > /sys/devices/system/cpu/cpu2/online
        # perf record usleep 1
        # perf report --header-only | grep 'nrcpus \(online\|avail\)'
        # nrcpus online : 4
        # nrcpus avail : 3
        # echo 0 > /sys/devices/system/cpu/cpu1/online
        # perf record usleep 1
        # perf report --header-only | grep 'nrcpus \(online\|avail\)'
        # nrcpus online : 4
        # nrcpus avail : 2
      
      After the fix, bringing back the CPUs online:
      
        # perf report --header-only | grep 'nrcpus \(online\|avail\)'
        # nrcpus online : 2
        # nrcpus avail : 4
        # echo 1 > /sys/devices/system/cpu/cpu2/online
        # perf record usleep 1
        # perf report --header-only | grep 'nrcpus \(online\|avail\)'
        # nrcpus online : 3
        # nrcpus avail : 4
        # echo 1 > /sys/devices/system/cpu/cpu1/online
        # perf record usleep 1
        # perf report --header-only | grep 'nrcpus \(online\|avail\)'
        # nrcpus online : 4
        # nrcpus avail : 4
      Acked-by: NNamhyung Kim <namhyung@kernel.org>
      Cc: Adrian Hunter <adrian.hunter@intel.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: David Ahern <dsahern@gmail.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Jiri Olsa <jolsa@kernel.org>
      Cc: Kan Liang <kan.liang@intel.com>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Wang Nan <wangnan0@huawei.com>
      Fixes: fbe96f29 ("perf tools: Make perf.data more self-descriptive (v8)")
      Link: http://lkml.kernel.org/r/20150911153323.GP23511@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      caa47047
  4. 03 9月, 2015 1 次提交
    • A
      perf tools: Fix use of wrong event when processing exit events · 53ff6bc3
      Adrian Hunter 提交于
      In a couple of cases the 'comm' member of 'union event' has been used
      instead of the correct member ('fork') when processing exit events.
      
      In the cases where it has been used incorrectly, only the 'pid' and
      'tid' are affected.  The 'pid' value would be correct anyway because it
      is in the same position in 'comm' and 'fork' events, but the 'tid' would
      have been incorrectly assigned from 'ppid'.
      
      However, for exit events, the kernel puts the current task in the 'ppid'
      and 'ttid' which is the same as the exiting task.  That is 'ppid' ==
      'pid' and if the task is not multi-threaded, 'pid' == 'tid' i.e. the
      data goes wrong only when tracing multi-threaded programs.
      
      It is hard to find an example of how this would produce an error in
      practice.  There are 3 occurences of the fix:
      
      1. perf script is only affected if !sample_id_all which only happens on
        old kernels.
      
      2. intel_pt is only affected when decoding without timestamps
         and would probably still decode correctly - the exit event is
         only used to flush out data which anyway gets flushed at the
         end of the session
      
      3. intel_bts also uses the exit event to flush data which
         would probably not cause errors as it would get flushed at
         the end of the session instead
      Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Link: http://lkml.kernel.org/r/1439888825-27708-1-git-send-email-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      53ff6bc3
  5. 02 9月, 2015 3 次提交
  6. 01 9月, 2015 7 次提交
  7. 29 8月, 2015 8 次提交
  8. 28 8月, 2015 3 次提交
  9. 26 8月, 2015 1 次提交
    • W
      perf probe: Support probing at absolute address · da15bd9d
      Wang Nan 提交于
      It should be useful to allow 'perf probe' probe at absolute offset of a
      target. For example, when (u)probing at a instruction of a shared object
      in a embedded system where debuginfo is not avaliable but we know the
      offset of that instruction by manually digging.
      
      This patch enables following perf probe command syntax:
      
        # perf probe 0xffffffff811e6615
      
      And
      
        # perf probe /lib/x86_64-linux-gnu/libc-2.19.so 0xeb860
      
      In the above example, we don't need a anchor symbol, so it is possible
      to compute absolute addresses using other methods and then use 'perf
      probe' to create the probing points.
      
      v1 -> v2:
        Drop the leading '+' in cmdline;
        Allow uprobing at offset 0x0;
        Improve 'perf probe -l' result when uprobe at area without debuginfo.
      
      v2 -> v3:
        Split bugfix to a separated patch.
      
      Test result:
      
        # perf probe 0xffffffff8119d175 %ax
        # perf probe sys_write %ax
        # perf probe /lib64/libc-2.18.so 0x0 %ax
        # perf probe /lib64/libc-2.18.so 0x5 %ax
        # perf probe /lib64/libc-2.18.so 0xd8e40 %ax
        # perf probe /lib64/libc-2.18.so __write %ax
        # perf probe /lib64/libc-2.18.so 0xd8e49 %ax
        # cat /sys/kernel/debug/tracing/uprobe_events
      
        p:probe_libc/abs_0 /lib64/libc-2.18.so:0x          (null) arg1=%ax
        p:probe_libc/abs_5 /lib64/libc-2.18.so:0x0000000000000005 arg1=%ax
        p:probe_libc/abs_d8e40 /lib64/libc-2.18.so:0x00000000000d8e40 arg1=%ax
        p:probe_libc/__write /lib64/libc-2.18.so:0x00000000000d8e40 arg1=%ax
        p:probe_libc/abs_d8e49 /lib64/libc-2.18.so:0x00000000000d8e49 arg1=%ax
      
        # cat /sys/kernel/debug/tracing/kprobe_events
      
        p:probe/abs_ffffffff8119d175 0xffffffff8119d175 arg1=%ax
        p:probe/sys_write _text+1692016 arg1=%ax
      
        # perf probe -l
      
        Failed to find debug information for address 5
          probe:abs_ffffffff8119d175 (on sys_write+5 with arg1)
          probe:sys_write      (on sys_write with arg1)
          probe_libc:__write   (on @unix/syscall-template.S:81 in /lib64/libc-2.18.so with arg1)
          probe_libc:abs_0     (on 0x0 in /lib64/libc-2.18.so with arg1)
          probe_libc:abs_5     (on 0x5 in /lib64/libc-2.18.so with arg1)
          probe_libc:abs_d8e40 (on @unix/syscall-template.S:81 in /lib64/libc-2.18.so with arg1)
          probe_libc:abs_d8e49 (on __GI___libc_write+9 in /lib64/libc-2.18.so with arg1)
      Signed-off-by: NWang Nan <wangnan0@huawei.com>
      Acked-by: NMasami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Zefan Li <lizefan@huawei.com>
      Cc: pi3orama@163.com
      Link: http://lkml.kernel.org/r/1440586666-235233-7-git-send-email-wangnan0@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      da15bd9d