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  1. 12 8月, 2015 3 次提交
  3. 06 8月, 2015 2 次提交
    • M
      perf trace: Add total time column to summary. · 834fd46d
      由 Milian Wolff 提交于 
      It is cumbersome to manually calculate the total time spent in a given
syscall by multiplying the average value with the number of calls.

Instead, we now do this directly inside perf trace.

Note that this is also done by 'strace', which even adds a column with
relative numbers - something we could do in the future.

Example:

  perf trace -s find /some/folder > /dev/null

   Summary of events:

   find (19976), 700123 events, 100.0%, 0.000 msec

     syscall            calls    total       min       avg       max      stddev
                                 (msec)    (msec)    (msec)    (msec)        (%)
     --------------- -------- --------- --------- --------- ---------     ------
     read                   4     0.006     0.001     0.002     0.003     27.42%
     write               8046     9.617     0.001     0.001     0.035      0.56%
     open               34196    40.384     0.001     0.001     0.071      0.30%
     close              68375    57.104     0.001     0.001     0.076      0.25%
     stat                   4     0.004     0.001     0.001     0.001      3.14%
     fstat              34189    27.518     0.001     0.001     0.060      0.34%
     mmap                  13     0.029     0.001     0.002     0.003     10.74%
     mprotect               6     0.018     0.002     0.003     0.005     17.04%
     munmap                 3     0.014     0.003     0.005     0.006     24.87%
     brk                   87     0.490     0.001     0.006     0.016      6.50%
     ioctl                  3     0.004     0.001     0.001     0.003     36.39%
     access                 1     0.004     0.004     0.004     0.004      0.00%
     uname                  1     0.001     0.001     0.001     0.001      0.00%
     getdents           68393   143.600     0.001     0.002     0.187      0.95%
     fchdir             68371    56.980     0.001     0.001     0.111      0.39%
     arch_prctl             1     0.001     0.001     0.001     0.001      0.00%
     openat             34184    41.737     0.001     0.001     0.102      0.41%
     newfstatat         34184    41.180     0.001     0.001     0.064      0.34%
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
LPU-Reference: 1438853069-5902-1-git-send-email-milian.wolff@kdab.com
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      834fd46d
    • M
      perf trace: Write to stderr by default · 007d66a0
      由 Milian Wolff 提交于 
      Without this patch, it is cumbersome to read the trace output but
ignoring the normal, potentially verbose, output of the debuggee.  One
common example is doing something like the following:

 perf trace -s find /tmp > /dev/null

Without this patch, the trace summary will be lost. Now, it will still
be printed at the end. This behavior is also applied by strace.

Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/n/tip-tqnks6y2cnvm5f9g2dsfr7zl@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      007d66a0
  5. 05 8月, 2015 5 次提交
    • A
      perf trace: Use vfs_getname syscall arg beautifier in more syscalls · 34221118
      由 Arnaldo Carvalho de Melo 提交于 
      Those were covered and tested in this cset:

 access, chdir, chmod, chown, chroot, creat, getxattr,
 inotify_add_watch, lchown, lgetxattr, listxattr,
 lsetxattr, mkdir, mkdirat, mknod, rmdir, faccessat,
 newfstatat, openat, readlink, readlinkat, removexattr,
 setxattr, statfs, swapon, swapoff, truncate, unlinkat,
 utime, utimes, utimensat.

E.g.:

  # trace -e statfs,access,mkdir mkdir /tmp/bla
   0.285 (0.020 ms): mkdir/2799 access(filename: /etc/ld.so.preload, mode: R         ) = -1 ENOENT No such file or directory
   1.070 (0.032 ms): mkdir/2799 statfs(pathname: /sys/fs/selinux, buf: 0x7ffeafbdc930) = 0
   1.087 (0.013 ms): mkdir/2799 statfs(pathname: /sys/fs/selinux, buf: 0x7ffeafbdc820) = 0
   1.189 (0.014 ms): mkdir/2799 access(filename: /etc/selinux/config                 ) = 0
   1.905 (0.610 ms): mkdir/2799 mkdir(pathname: /tmp/bla, mode: 511                  ) = 0
  #

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@redhat.com>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wbqtnlktquun3wtpjdz3okul@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

  and an empty message aborts the commit.
      34221118
    • A
      perf trace: Deref sys_enter pointer args with contents from probe:vfs_getname · f994592d
      由 Arnaldo Carvalho de Melo 提交于 
      To work like strace and dereference syscall pointer args we need to
insert probes (or tracepoints) right after we copy those bytes from
userspace.

Since we're formatting the syscall args at raw_syscalls:sys_enter time,
we need to have a formatter that just stores the position where, later,
when we get the probe:vfs_getname, we can insert the pointer contents.

Now, if a probe:vfs_getname with this format is in place:

 # perf probe -l
  probe:vfs_getname (on getname_flags:72@/home/git/linux/fs/namei.c with pathname)

That was, in this case, put in place with:

 # perf probe 'vfs_getname=getname_flags:72 pathname=filename:string'
 Added new event:
  probe:vfs_getname    (on getname_flags:72 with pathname=filename:string)

 You can now use it in all perf tools, such as:

	perf record -e probe:vfs_getname -aR sleep 1
 #

Then 'perf trace' will notice that and do the pointer -> contents
expansion:

 # trace -e open touch /tmp/bla
  0.165 (0.010 ms): touch/17752 open(filename: /etc/ld.so.cache, flags: CLOEXEC) = 3
  0.195 (0.011 ms): touch/17752 open(filename: /lib64/libc.so.6, flags: CLOEXEC) = 3
  0.512 (0.012 ms): touch/17752 open(filename: /usr/lib/locale/locale-archive, flags: CLOEXEC) = 3
  0.582 (0.012 ms): touch/17752 open(filename: /tmp/bla, flags: CREAT|NOCTTY|NONBLOCK|WRONLY, mode: 438) = 3
 #

Roughly equivalent to strace's output:

 # strace -rT -e open touch /tmp/bla
  0.000000 open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3 <0.000039>
  0.000317 open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3 <0.000102>
  0.001461 open("/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3 <0.000072>
  0.000405 open("/tmp/bla", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3 <0.000055>
  0.000641 +++ exited with 0 +++
 #

Now we need to either look for at all syscalls that are marked as
pointers and have some well known names ("filename", "pathname", etc)
and set the arg formatter to the one used for the "open" syscall in this
patch.

This implementation works for syscalls with just a string being copied
from userspace, for matching syscalls with more than one string being
copied via the same probe/trace point (vfs_getname) we need to extend
the vfs_getname probe spec to include the pointer too, but there are
some problems with that in 'perf probe' or the kernel kprobes code, need
to investigate before considering supporting multiple strings per
syscall.

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@redhat.com>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-xvuwx6nuj8cf389kf9s2ue2s@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      f994592d
    • A
      perf trace: Use a constant for the syscall formatting buffer · e4d44e83
      由 Arnaldo Carvalho de Melo 提交于 
      We were using it as a magic number, 1024, fix that.

Eventually we need to stop doing it per line, and do it per
arg, traversing the args at output time, to avoid the memmove()
calls that will be used in the next cset to replace pointers
present at raw_syscalls:sys_enter time with its contents that
appear at probe:vfs_getname time, before raw_syscalls:sys_exit
time.

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@redhat.com>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-4sz3wid39egay1pp8qmbur4u@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e4d44e83
    • A
      perf trace: Remember if the vfs_getname tracepoint/kprobe is in place · 08c98776
      由 Arnaldo Carvalho de Melo 提交于 
      So that we can later decide if we will store where to expand the
pathname once we are handling vfs_getname or if we should instead
just go on and straight away print the pointer.

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@redhat.com>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-ytxk5s5jpc50wahffmlxgxuw@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      08c98776
    • A
      perf trace: Do not show syscall tracepoint filter in the --no-syscalls case · 2e5e5f87
      由 Arnaldo Carvalho de Melo 提交于 
      We were accessing trace->syscalls.events members even when that struct
wasn't initialized, i.e. --no-syscalls was specified on the command
line, fix it to show that, still in debug mode, when we have an event
qualifier list, i.e. when we actually are doing subset syscall tracing.

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@redhat.com>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: 19867b61 ("perf trace: Use event filters for the event qualifier list")
Link: http://lkml.kernel.org/n/tip-7980ym6vujgh3yiai0cqzc88@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      2e5e5f87
  7. 29 7月, 2015 1 次提交
    • A
      perf python: Remove dependency on 'machine' methods · 959c2199
      由 Arnaldo Carvalho de Melo 提交于 
      The python binding still doesn't provide symbol resolving facilities,
but the recent addition of the trace_event__register_resolver() function
made it add as a dependency the machine__resolve_kernel_addr() method,
that in turn drags all the symbol resolving code.

The problem:

  [root@zoo ~]# perf test -v python
  17: Try 'import perf' in python, checking link problems      :
  --- start ---
  test child forked, pid 6853
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  ImportError: /tmp/build/perf/python/perf.so: undefined symbol: machine__resolve_kernel_addr
  test child finished with -1
  ---- end ----
  Try 'import perf' in python, checking link problems: FAILED!
  [root@zoo ~]#

Fix it by requiring this function to receive the resolver as a
parameter, just like pevent_register_function_resolver(), i.e. do
not explicitely refer to an object file not included in
tools/perf/util/python-ext-sources.

  [root@zoo ~]# perf test python
  17: Try 'import perf' in python, checking link problems      : Ok
  [root@zoo ~]#

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@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: c3168b0d ("perf symbols: Provide libtraceevent callback to resolve kernel symbols")
Link: http://lkml.kernel.org/n/tip-vxlhh95v2em9zdbgj3jm7xi5@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      959c2199
  9. 24 7月, 2015 1 次提交
  11. 21 7月, 2015 1 次提交
    • A
      perf trace: Support 'strace' syscall event groups · 005438a8
      由 Arnaldo Carvalho de Melo 提交于 
      I.e.:

  $ cat ~/share/perf-core/strace/groups/file
  access
  chmod
  creat
  execve
  faccessat
  getcwd
  lstat
  mkdir
  open
  openat
  quotactl
  readlink
  rename
  rmdir
  stat
  statfs
  symlink
  unlink
  $

Then, on a quiet desktop, try running this and then moving your mouse to
see the deluge of mouse related activity:

  # perf probe 'vfs_getname=getname_flags:72 pathname=filename:string'
  Added new event:
    probe:vfs_getname    (on getname_flags:72 with pathname=filename:string)

  You can now use it in all perf tools, such as:

	perf record -e probe:vfs_getname -aR sleep 1
  #
  # trace --ev probe:vfs_getname --filter-pids 2232 -e file
   0.042 (0.042 ms): mousetweaks/2235 open(filename: 0x14e3910, mode: 438                                   ) ...
   0.042 (        ): probe:vfs_getname:(ffffffff812230bc) pathname="/home/acme/.icons/Adwaita/cursors/xterm")
   0.100 (0.100 ms): mousetweaks/2235  ... [continued]: open()) = -1 ENOENT No such file or directory
   0.142 (0.018 ms): mousetweaks/2235 open(filename: 0x14c3c10, mode: 438                                   ) ...
   0.142 (        ): probe:vfs_getname:(ffffffff812230bc) pathname="/home/acme/.icons/Adwaita/index.theme")
   0.192 (0.069 ms): mousetweaks/2235  ... [continued]: open()) = -1 ENOENT No such file or directory
   0.230 (0.017 ms): mousetweaks/2235 open(filename: 0x14c3c10, mode: 438                                   ) ...
   0.230 (        ): probe:vfs_getname:(ffffffff812230bc) pathname="/usr/share/icons/Adwaita/cursors/xterm")
   0.253 (0.041 ms): mousetweaks/2235  ... [continued]: open()) = 14
   0.459 (0.008 ms): mousetweaks/2235 open(filename: 0x14e3910, mode: 438                                   ) ...
   0.459 (        ): probe:vfs_getname:(ffffffff812230bc) pathname="/home/acme/.icons/Adwaita/cursors/left_side")
   0.468 (0.017 ms): mousetweaks/2235  ... [continued]: open()) = -1 ENOENT No such file or directory

Need to combine that raw_syscalls:sys_enter(open) + probe:vfs_getname +
raw_syscalls:sys_exit(open) sequence...

Now, if you're bored, please write some more syscall groups, like the ones
in 'strace' and send it our way :-)

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@redhat.com>
Cc: Milian Wolff <mail@milianw.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-a42xklu59lcbxp7bbnic74a8@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      005438a8
  13. 20 7月, 2015 1 次提交
  15. 06 7月, 2015 4 次提交
    • A
      perf trace: Use event filters for the event qualifier list · 19867b61
      由 Arnaldo Carvalho de Melo 提交于 
      We use raw_syscalls:sys_{enter,exit} events to show the syscalls, but were
using a rather lazy/inneficient way to implement our 'strace -e' equivalent:
filter out after reading the events in the ring buffer.

Deflect more work to the kernel by appending a filter expression for that,
that, together with the pid list, that is always present, if only to filter the
tracer itself, reduces pressure on the ring buffer and otherwise use
infrastructure already in place in the kernel to do early filtering.

If we use it with -v we can see the filter passed to the kernel,
for instance, for this contrieved case:

  # trace -v -e \!open,close,write,poll,recvfrom,select,recvmsg,writev,sendmsg,read,futex,epoll_wait,ioctl,eventfd --filter-pids 2189,2566,1398,2692,4475,4532
<SNIP>
  (common_pid != 2514 && common_pid != 1398 && common_pid != 2189 && common_pid != 2566 && common_pid != 2692 && common_pid != 4475 && common_pid != 4532) && (id != 3 && id != 232 && id != 284 && id != 202 && id != 16 && id != 2 && id != 7 && id != 0 && id != 45 && id != 47 && id != 23 && id != 46 && id != 1 && id != 20)
     0.011 (0.011 ms): caribou/2295 eventfd2(flags: CLOEXEC|NONBLOCK) = 18
    16.946 (0.019 ms): caribou/2295 eventfd2(flags: CLOEXEC|NONBLOCK) = 18
    38.598 (0.167 ms): chronyd/794 socket(family: INET, type: DGRAM ) = 4
    38.603 (0.002 ms): chronyd/794 fcntl(fd: 4<socket:[239307]>, cmd: GETFD) = 0
    38.605 (0.001 ms): chronyd/794 fcntl(fd: 4<socket:[239307]>, cmd: SETFD, arg: 1) = 0
^C
 #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-ti2tg18atproqpguc2moinp6@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      19867b61
    • A
      perf evlist: Make perf_evlist__set_filter use perf_evsel__set_filter · 94ad89bc
      由 Arnaldo Carvalho de Melo 提交于 
      Instead of calling perf_evsel__apply_filter straight away, so that
we can, in the next patches, expand the filter with more conditions
before actually calling the ioctl to pass the end result filter to
the kernel.

Now we need to call perf_evlist__apply_filters() after the filter
is completely setup, i.e. do the ioctl calls.

The perf_evlist__apply_filters() method was already in place, because
that is the model for the other tools that receives filters in the
command line: go on setting then in the evsel->filter and only at
the end, after parsing the whole command line, apply them.

We get, as a bonus, a more expressive message that states which
event, if any, failed to have the filter applied to, with an
error message stating what happened.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-f429pgz75ryz7tpe6v74etre@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      94ad89bc
    • A
      perf trace: Store the syscall ids for the event qualifiers in a table · 8b3ce757
      由 Arnaldo Carvalho de Melo 提交于 
      That we will use to set a filter on raw_syscalls:sys_{enter,exit}
events.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-2acxrcxyu7tlolrfilpty38y@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      8b3ce757
    • A
      perf trace: Remember what are the syscalls tracepoint evsels · c27366f0
      由 Arnaldo Carvalho de Melo 提交于 
      We will need to set filters on then.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-u8hpgjpf3w8o1prnnjnwegwf@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      c27366f0
  17. 26 6月, 2015 1 次提交
    • A
      perf trace: Validate syscall list passed via -e argument · d0cc439b
      由 Arnaldo Carvalho de Melo 提交于 
      The 'trace' tool was accepting any names passed and just looking if
syscalls returned via the raw_syscalls:* tracepoints were in that list,
leading to it accepting perf events and then never finding any, as those
are not valid syscall names, confusing users.

Fix it by checking each entry in the list using audit_name_to_syscall,
telling the user which entries are invalid and suggesting where to look
for valid syscall names.

E.g:

  [root@zoo ~]# trace -e open,foo,bar,close,baz
  Error: Invalid syscall bar, baz, foo
  Hint:	 try 'perf list syscalls:sys_enter_*'
  Hint:	 and: 'man syscalls'
  [root@zoo ~]#
Reported-by: NFlavio Leitner <fbl@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-4g1i3m1z6fzsrznn2umi02wa@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      d0cc439b
  19. 24 6月, 2015 1 次提交
  21. 20 6月, 2015 1 次提交
  23. 12 6月, 2015 1 次提交
    • A
      trace: Beautify perf_event_open syscall · a1c2552d
      由 Arnaldo Carvalho de Melo 提交于 
      Syswide tracing and then running 'stat' and 'trace':

 $ perf trace -e perf_event_open
 1034.649 (0.019 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = -1 EINVAL Invalid argument
 1034.670 (0.008 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1) = -1 EINVAL Invalid argument
 1034.681 (0.007 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1) = -1 EINVAL Invalid argument
 1034.692 (0.007 ms): perf/6133 perf_event_open(attr_uptr: 0x36f0360, pid: 16134, cpu: -1, group_fd: -1) = -1 EINVAL Invalid argument
 9986.983 (0.014 ms): trace/6139 perf_event_open(attr_uptr: 0x7ffd9c629320, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.026 (0.016 ms): trace/6139 perf_event_open(attr_uptr: 0x37c7e70, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.041 (0.008 ms): trace/6139 perf_event_open(attr_uptr: 0x37c7e70, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.489 (0.092 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, group_fd: -1, flags: FD_CLOEXEC) = 3
 9987.536 (0.044 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 4
 9987.580 (0.041 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 5
 9987.620 (0.037 ms): trace/6139 perf_event_open(attr_uptr: 0x3795ee0, pid: 16140, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 7
 9987.659 (0.035 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, group_fd: -1, flags: FD_CLOEXEC) = 8
 9987.692 (0.031 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 9
 9987.727 (0.032 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 10
 9987.761 (0.031 ms): trace/6139 perf_event_open(attr_uptr: 0x37975d0, pid: 16140, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 11

Need to intercept perf_copy_attr() with a kprobe or with eBPF...

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@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-njb105hab2i3t5dexym9lskl@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a1c2552d
  25. 15 5月, 2015 1 次提交
  27. 12 5月, 2015 1 次提交
  29. 09 5月, 2015 1 次提交
    • A
      perf machine: Protect the machine->threads with a rwlock · b91fc39f
      由 Arnaldo Carvalho de Melo 提交于 
      In addition to using refcounts for the struct thread lifetime
management, we need to protect access to machine->threads from
concurrent access.

That happens in 'perf top', where a thread processes events, inserting
and deleting entries from that rb_tree while another thread decays
hist_entries, that end up dropping references and ultimately deleting
threads from the rb_tree and releasing its resources when no further
hist_entry (or other data structures, like in 'perf sched') references
it.

So the rule is the same for refcounts + protected trees in the kernel,
get the tree lock, find object, bump the refcount, drop the tree lock,
return, use object, drop the refcount if no more use of it is needed,
keep it if storing it in some other data structure, drop when releasing
that data structure.

I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and
"perf_event__preprocess_sample(&al)" with "addr_location__put(&al)".

The addr_location__put() one is because as we return references to
several data structures, we may end up adding more reference counting
for the other data structures and then we'll drop it at
addr_location__put() time.
Acked-by: NDavid Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b91fc39f
  31. 29 4月, 2015 2 次提交
  33. 24 4月, 2015 2 次提交
    • A
      perf trace: Disable events and drain events when forked workload ends · 02ac5421
      由 Arnaldo Carvalho de Melo 提交于 
      We were not checking in the inner event processing loop if the forked workload
had finished, which, on a busy system, may make it take a long time trying to
drain events, entering a seemingly neverending loop, waiting for the system to
get idle enough to make it drain the buffers.

Fix it by disabling the events when 'done' is true, in the inner loop, to start
draining what is in the buffers.

Now:

[root@ssdandy ~]# time trace --filter-pids 14003 -a sleep 1 | tail
  996.748 ( 0.002 ms): sh/30296 rt_sigprocmask(how: SETMASK, nset: 0x7ffc83418160, sigsetsize: 8) = 0
  996.751 ( 0.002 ms): sh/30296 rt_sigprocmask(how: BLOCK, nset: 0x7ffc834181f0, oset: 0x7ffc83418270, sigsetsize: 8) = 0
  996.755 ( 0.002 ms): sh/30296 rt_sigaction(sig: INT, act: 0x7ffc83417f50, oact: 0x7ffc83417ff0, sigsetsize: 8) = 0
 1004.543 ( 0.362 ms): tail/30198  ... [continued]: read()) = 4096
 1004.548 ( 7.791 ms): sh/30296 wait4(upid: -1, stat_addr: 0x7ffc834181a0) ...
 1004.975 ( 0.427 ms): tail/30198 read(buf: 0x7633f0, count: 8192) = 4096
 1005.390 ( 0.410 ms): tail/30198 read(buf: 0x765410, count: 8192) = 4096
 1005.743 ( 0.348 ms): tail/30198 read(buf: 0x7633f0, count: 8192) = 4096
 1006.197 ( 0.449 ms): tail/30198 read(buf: 0x765410, count: 8192) = 4096
 1006.492 ( 0.290 ms): tail/30198 read(buf: 0x7633f0, count: 8192) = 4096

real	0m1.219s
user	0m0.704s
sys	0m0.331s
[root@ssdandy ~]#
Reported-by: NMichael Petlan <mpetlan@redhat.com>
Suggested-by: NJiri Olsa <jolsa@redhat.com>
Acked-by: NJiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-p6kpn1b26qcbe47pufpw0tex@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      02ac5421
    • A
      perf trace: Enable events when doing system wide tracing and starting a workload · cb24d01d
      由 Arnaldo Carvalho de Melo 提交于 
       commit f7aa222f
 Author: Arnaldo Carvalho de Melo <acme@redhat.com>
 Date:   Tue Feb 3 13:25:39 2015 -0300

    perf trace: No need to enable evsels for workload started from perf

The assumption was that whenever a workload is specified, the
attr.enable_on_exec evsel flag would be set, but that is not happening
when perf_record_opts.system_wide is set, for instance

That resulted in both perf_evlist__enable() and attr.enable_on_exec
being not called/set, which made the events to remain disabled while the
workload runs, producing no output.

Fix it,  by calling perf_evlist__enable() in the 'trace' tool
when forking and not targetting a workload started from trace

v2: Test against !target__none(), as suggested by Namhyung Kim, that is
what is used in perf_evsel__config() when deciding if the
attr.enable_on_exec flag to be set. More work is needed to cover other
cases such as opts->initial_delay.
Acked-by: NJiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-27z7169pvfxgj8upic636syv@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      cb24d01d
  35. 03 4月, 2015 1 次提交
    • Y
      perf trace: Support using -f to override perf.data file ownership · e366a6d8
      由 Yunlong Song 提交于 
      Enable perf trace to use perf.data when it is not owned by current user
or root.

Example:

 # perf trace record ls
 # chown Yunlong.Song:Yunlong.Song perf.data
 # ls -al perf.data
 -rw------- 1 Yunlong.Song Yunlong.Song 4153101 Apr  2 15:28 perf.data
 # id
 uid=0(root) gid=0(root) groups=0(root),64(pkcs11)

Before this patch:

 # perf trace -i perf.data
 File perf.data not owned by current user or root (use -f to override)
 # perf trace -i perf.data -f
   Error: unknown switch `f'

  usage: perf trace [<options>] [<command>]
     or: perf trace [<options>] -- <command> [<options>]
     or: perf trace record [<options>] [<command>]
     or: perf trace record [<options>] -- <command> [<options>]

         --event <event>   event selector. use 'perf list' to list
 						  available events
         --comm            show the thread COMM next to its id
         --tool_stats      show tool stats
     -e, --expr <expr>     list of events to trace
     -o, --output <file>   output file name
     -i, --input <file>    Analyze events in file
     -p, --pid <pid>       trace events on existing process id
     -t, --tid <tid>       trace events on existing thread id
         --filter-pids <float>
  ...

As shown above, the -f option does not work at all.

After this patch:

 # perf trace -i perf.data
 File perf.data not owned by current user or root (use -f to override)
 # perf trace -i perf.data -f
 0.056 ( 0.002 ms): ls/47325 brk(                                 ...
 0.108 ( 0.018 ms): ls/47325 mmap(len: 4096, prot: READ|WRITE,    ...
 0.145 ( 0.013 ms): ls/47325 access(filename: 0x7f31259a0eb0,     ...
 0.172 ( 0.008 ms): ls/47325 open(filename: 0x7fffeb9a0d00,       ...
 0.180 ( 0.004 ms): ls/47325 stat(filename: 0x7fffeb9a0d00,       ...
 0.185 ( 0.004 ms): ls/47325 open(filename: 0x7fffeb9a0d00,       ...
 0.189 ( 0.003 ms): ls/47325 stat(filename: 0x7fffeb9a0d00,       ...
 0.195 ( 0.004 ms): ls/47325 open(filename: 0x7fffeb9a0d00,       ...
 0.199 ( 0.002 ms): ls/47325 stat(filename: 0x7fffeb9a0d00,       ...
 0.205 ( 0.004 ms): ls/47325 open(filename: 0x7fffeb9a0d00,       ...
 0.211 ( 0.004 ms): ls/47325 stat(filename: 0x7fffeb9a0d00,       ...
 0.220 ( 0.007 ms): ls/47325 open(filename: 0x7f312599e8ff,       ...
 ...
 ...

As shown above, the -f option really works now.
Signed-off-by: NYunlong Song <yunlong.song@huawei.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1427982439-27388-10-git-send-email-yunlong.song@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      e366a6d8
  37. 26 3月, 2015 1 次提交
    • A
      perf trace: Fix syscall enter formatting bug · 6ebad5c1
      由 Arnaldo Carvalho de Melo 提交于 
       commit e596663e
 Author: Arnaldo Carvalho de Melo <acme@redhat.com>
 Date:   Fri Feb 13 13:22:21 2015 -0300

    perf trace: Handle multiple threads better wrt syscalls being intermixed

Introduced a bug where it considered the number of bytes output directly
to the output file when formatting the syscall entry buffer that is
stored to be finally printed at syscall exit, ending up leaving garbage
at the start of syscalls that appeared while another syscall was being
processed, in another thread. Fix it.

Example of garbage in the output before this patch:

 4280.102 (  0.000 ms): lsmd/763  ... [continued]: select()) = 0 Timeout
 4280.107 (275.250 ms): tuned/852 select(tvp: 0x7f41f7ffde50        ) ...
 4280.109 (  0.002 ms): lsmd/763 Xl��                                ) = -10
 4639.197 (  0.000 ms): systemd-journa/542  ... [continued]: epoll_wait()) = 1
 4639.202 (359.088 ms): lsmd/763 select(n: 6, inp: 0x7ffff21daad0, tvp: 0x7ffff21daac0) ...
 4639.207 (  0.005 ms): systemd-journa/542 Hn��                      ) = 106
 4639.221 (  0.002 ms): systemd-journa/542 uname(name: 0x7ffdbaed8e00) = 0
 4639.271 (  0.008 ms): systemd-journa/542 ftruncate(fd: 11</run/log/journal/60cd52417cf440a4a80107518bbd3c20/system.journal>, length: 50331648) = 0

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-9ckfe8mvsedgkg6y80gz1ul8@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      6ebad5c1
  39. 22 3月, 2015 2 次提交
  41. 20 3月, 2015 1 次提交
  43. 11 3月, 2015 1 次提交
  45. 03 3月, 2015 1 次提交
    • A
      perf tools: Reference count struct thread · f3b623b8
      由 Arnaldo Carvalho de Melo 提交于 
      We need to do that to stop accumulating entries in the dead_threads
linked list, i.e. we were keeping references to threads in struct hists
that continue to exist even after a thread exited and was removed from
the machine threads rbtree.

We still keep the dead_threads list, but just for debugging, allowing us
to iterate at any given point over the threads that still are referenced
by things like struct hist_entry.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-3ejvfyed0r7ue61dkurzjux4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      f3b623b8
  47. 26 2月, 2015 1 次提交
    • D
      perf trace: Fix SIGBUS failures due to misaligned accesses · 55d43bca
      由 David Ahern 提交于 
      On Sparc64 perf-trace is failing in many spots due to extended load
instructions being used on misaligned accesses.

(gdb) run trace ls
Starting program: /tmp/perf/perf trace ls
[Thread debugging using libthread_db enabled]
Detaching after fork from child process 169460.

<ls output removed>

Program received signal SIGBUS, Bus error.
0x000000000014f4dc in tp_field__u64 (field=0x4cc700, sample=0x7feffffa098) at builtin-trace.c:61
warning: Source file is more recent than executable.
61      TP_UINT_FIELD(64);

(gdb) bt
 0  0x000000000014f4dc in tp_field__u64 (field=0x4cc700, sample=0x7feffffa098) at builtin-trace.c:61
 1  0x0000000000156ad4 in trace__sys_exit (trace=0x7feffffc268, evsel=0x4cc580, event=0xfffffc0104912000,
    sample=0x7feffffa098) at builtin-trace.c:1701
 2  0x0000000000158c14 in trace__run (trace=0x7feffffc268, argc=1, argv=0x7fefffff360) at builtin-trace.c:2160
 3  0x000000000015b78c in cmd_trace (argc=1, argv=0x7fefffff360, prefix=0x0) at builtin-trace.c:2609
 4  0x0000000000107d94 in run_builtin (p=0x4549c8, argc=2, argv=0x7fefffff360) at perf.c:341
 5  0x0000000000108140 in handle_internal_command (argc=2, argv=0x7fefffff360) at perf.c:400
 6  0x0000000000108308 in run_argv (argcp=0x7feffffef2c, argv=0x7feffffef20) at perf.c:444
 7  0x0000000000108728 in main (argc=2, argv=0x7fefffff360) at perf.c:559

(gdb) p *sample
$1 = {ip = 4391276, pid = 169472, tid = 169472, time = 6303014583281250, addr = 0, id = 72082,
  stream_id = 18446744073709551615, period = 1, weight = 0, transaction = 0, cpu = 73, raw_size = 36,
  data_src = 84410401, flags = 0, insn_len = 0, raw_data = 0xfffffc010491203c, callchain = 0x0,
  branch_stack = 0x0, user_regs = {abi = 0, mask = 0, regs = 0x0, cache_regs = 0x7feffffa098, cache_mask = 0},
  intr_regs = {abi = 0, mask = 0, regs = 0x0, cache_regs = 0x7feffffa098, cache_mask = 0}, user_stack = {
    offset = 0, size = 0, data = 0x0}, read = {time_enabled = 0, time_running = 0, {group = {nr = 0,
        values = 0x0}, one = {value = 0, id = 0}}}}
(gdb) p *field
$2 = {offset = 16, {integer = 0x14f4a8 <tp_field__u64>, pointer = 0x14f4a8 <tp_field__u64>}}

sample->raw_data is guaranteed to not be 8-byte aligned because it is preceded
by the size as a u3. So accessing raw data with an extended load instruction causes
the SIGBUS. Resolve by using memcpy to a temporary variable of appropriate size.
Signed-off-by: NDavid Ahern <david.ahern@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1424376022-140608-1-git-send-email-david.ahern@oracle.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      55d43bca
  49. 25 2月, 2015 1 次提交
    • A
      perf trace: Dump stack on segfaults · 4d08cb80
      由 Arnaldo Carvalho de Melo 提交于 
        [root@ssdandy ~]# perf trace --filter-pids 16348
     0.000 ( 0.000 ms): tuned/1027  ... [continued]: select()) = 0 Timeout
   793.770 ( 0.000 ms): lsmd/895  ... [continued]: select()) = 0 Timeout
   793.775 (793.724 ms): tuned/1027 select(tvp: 0x7f7655556e50) ...
  perf: Segmentation fault
  Obtained 15 stack frames.
  perf(dump_stack+0x2e) [0x4ed330]
  perf(sighandler_dump_stack+0x2e) [0x4ed40f]
  /lib64/libc.so.6(+0x35640) [0x7fa2d5b69640]
  perf() [0x4c2d35]
  perf(machine__findnew_thread+0x39) [0x4c2ed6]
  perf() [0x454a4d]
  perf() [0x455f87]
  perf() [0x456556]
  perf(cmd_trace+0xa7e) [0x4580af]
  perf() [0x4867bd]
  perf() [0x486a1c]
  perf() [0x486b68]
  perf(main+0x23b) [0x486ec9]
  /lib64/libc.so.6(__libc_start_main+0xf5) [0x7fa2d5b55af5]
  perf() [0x41bd91]
[  root@ssdandy ~]#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-v38cbxcnm2yf5qn9u4y4n9ab@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      4d08cb80
  51. 23 2月, 2015 2 次提交
    • A
      perf trace: Separate routine that handles an event from the one that reads it · ddbb1b13
      由 Arnaldo Carvalho de Melo 提交于 
      Because we need to use ordered_events in some cases, so we will need to
first have them in a queue, order that queue, and then process the
event.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-cmkw9zgoh0z4r218957ftp1a@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      ddbb1b13
    • A
      perf trace: Introduce --filter-pids · f078c385
      由 Arnaldo Carvalho de Melo 提交于 
      When tracing in X we get event loops due to the tracing activity, i.e.
updates to a gnome-terminal that generate syscalls for X.org, etc.

To get a more useful view of what is happening, syscall wise, system
wide, we need to filter those, like in:

 # ps ax|egrep '981|2296|1519' | grep -v egrep
   981 tty1 Ss+ 5:40 /usr/bin/Xorg :0 -background none ...
  1519 ?    Sl  2:22 /usr/bin/gnome-shell
  2296 ?    Sl  4:16 /usr/libexec/gnome-terminal-server
 #

 # trace -e write --filter-pids 981,2296,1519
    0.385 ( 0.021 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 136) = 136
    0.922 ( 0.014 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 140) = 140
 5006.525 ( 0.029 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 136) = 136
 5007.235 ( 0.023 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 140) = 140
 5177.646 ( 0.018 ms): rtkit-daemon/782 write(fd: 5<anon_inode:[eventfd]>, buf: 0x7f7eea70be88, count: 8) = 8
 8314.497 ( 0.004 ms): gsd-locate-poi/2084 write(fd: 5<anon_inode:[eventfd]>, buf: 0x7fffe96af7b0, count: 8) = 8
 8314.518 ( 0.002 ms): gsd-locate-poi/2084 write(fd: 5<anon_inode:[eventfd]>, buf: 0x7fffe96af0e0, count: 8) = 8
 ^C#

When this option is used the tracer pid is also filtered.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
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: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-f5qmiyy7c0uxdm21ncatpeek@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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