One can set a cgroup as a default cgroup to be used by all events or
set cgroups with the 'perf stat' and 'perf record' behaviour, i.e.
'-G A' will be the cgroup for events defined so far in the command line.

Here in my main machine, with a kvm instance running a rhel6 guinea pig
I have:

  # ls -la /sys/fs/cgroup/perf_event/ | grep drw
  drwxr-xr-x. 14 root root 360 Mar  6 12:04 ..
  drwxr-xr-x.  3 root root   0 Mar  6 15:05 machine.slice
  #

So I can go ahead and use that cgroup hierarchy, say lets see what
syscalls are being emitted by threads in that 'machine.slice' hierarchy
that are taking more than 100ms:

  # perf trace --duration 100 -G machine.slice
     0.188 (249.850 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
   250.274 (249.743 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
   500.224 (249.755 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
   750.097 (249.934 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
  1000.244 (249.780 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
  1250.197 (249.796 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
  1500.124 (249.859 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
  1750.076 (172.900 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
   902.570 (1021.116 ms): qemu-system-x8/23667 ppoll(ufds: 0x558151e03180, nfds: 74, tsp: 0x7ffc00cd0900, sigsetsize: 8) = 1
  1923.825 (305.133 ms): qemu-system-x8/23667 ppoll(ufds: 0x558151e03180, nfds: 74, tsp: 0x7ffc00cd0900, sigsetsize: 8) = 1
  2000.172 (229.002 ms): CPU 0/KVM/23744 ioctl(fd: 16<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
^C  #

If we look inside that cgroup hierarchy we get:

  # ls -la /sys/fs/cgroup/perf_event/machine.slice/ | grep drw
  drwxr-xr-x. 3 root root 0 Mar  6 15:05 .
  drwxr-xr-x. 2 root root 0 Mar  6 16:16 machine-qemu\x2d2\x2drhel6.sandy.scope
  #

There is just one, but lets say there were more and we would want to see
5 seconds worth of syscall summary for the threads in that cgroup:

  # perf trace --summary -G machine.slice/machine-qemu\\x2d2\\x2drhel6.sandy.scope/ -a sleep 5

   Summary of events:

     qemu-system-x86 (23667), 143858 events, 24.2%

     syscall            calls    total       min       avg       max      stddev
                                 (msec)    (msec)    (msec)    (msec)        (%)
     --------------- -------- --------- --------- --------- ---------     ------
     ppoll              28492  4348.631     0.000     0.153    11.616      1.05%
     futex              19661   140.801     0.001     0.007     2.993      3.20%
     read               18440    68.084     0.001     0.004     1.653      4.33%
     ioctl               5387    24.768     0.002     0.005     0.134      1.62%

     CPU 0/KVM (23744), 449455 events, 75.8%

     syscall            calls    total       min       avg       max      stddev
                               (msec)    (msec)    (msec)    (msec)        (%)
     --------------- -------- --------- --------- --------- ---------     ------
     ioctl             148364  3401.812     0.000     0.023    11.801      1.15%
     futex              36131   404.127     0.001     0.011     7.377      2.63%
     writev             29452   339.688     0.003     0.012     1.740      1.36%
     write              11315    45.992     0.001     0.004     0.105      1.10%

  #

See the documentation about how to set more than one cgroup for
different events in the same command line.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-t126jh4occqvu0xdqlcjygex@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The usual thing is for a constructor to allocate space for its members,
not to require that the caller pass a pre-allocated 'name' and then, at
its destructor, to free something not allocated by it.

Fix it by making cgroup__new() to receive a const char pointer, then
allocate cgroup->name that then can continue to be freed at
cgroup__delete(), balancing the alloc/free operations inside the cgroup
struct methods.

This eases calling evlist__findnew_cgroup() from the custom 'perf trace'
cgroup parser, that will only call parse_cgroups() when the '-G cgroup'
is passed on the command line after '-e event' entries, when it'll
behave just like 'perf stat' and 'perf record', i.e. the previous
parse_cgroup() users that mandate that -G only can come after a -e.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-4leugnuyqi10t98990o3xi1t@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

So that tools like 'perf trace' can allow the user to set a cgroup
to be used for all the evsels still without a crgroup setup by
parse_cgroups(), such as the one to use for the syscalls, vfs_getname
and other events involved in strace like syscall tracing.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-zf9jjsbj661r3lk6qb7g8j70@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Similar to machine__findnew_thread(), etc, i.e. try to find, get a
refcount if found and return it, otherwise return a new cgroup object.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-im1omevlihhyneiic4nl3g24@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

In preparation for adding AUX area sampling support, combine some
auxtrace initialization into a single function.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1520327598-1317-2-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This is to show the real name of thread that created via fork-exec.  See
below example for shortname *A0*.

$ sudo ./perf sched map
              *A0   80393.050639 secs A0 => perf:22368
          *.   A0   80393.050748 secs .  => swapper:0
           .  *.    80393.050887 secs
      *B0  .   .    80393.052735 secs B0 => rcu_sched:8
      *.   .   .    80393.052743 secs
       .  *C0  .    80393.056264 secs C0 => kworker/2:1H:287
       .  *A0  .    80393.056270 secs
       .  *D0  .    80393.056769 secs D0 => ksoftirqd/2:22
-      .  *A0  .    80393.056804 secs
+      .  *A0  .    80393.056804 secs A0 => pi:22368
       .  *.   .    80393.056854 secs
      *B0  .   .    80393.060727 secs
      ...
Signed-off-by: Changbin Du <changbin.du@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1520307457-23668-3-git-send-email-changbin.du@intel.com
[ Optimally pack struct thread_runtime when adding the new bool member ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The thread::shortname only used by sched command, so move it to sched
private structure.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1520307457-23668-2-git-send-email-changbin.du@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To follow the namespacing convention in tools/perf.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-jaalyl6bkvvji4r5u8wqw4n4@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To break down complexity in add_cgroup().

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-5yqshcf5hm837n7c86u7lhjf@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The refcount operation counterpart to cgroup__put(), use it when reusing
a cgroup.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-14ynvrl7y2cz8gyuy5q5v41g@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

It is not really closing the cgroup, but instead dropping a reference
count and if it hits zero, then calling delete, which will, among other
cleanup shores, close the cgroup fd.

So it is really dropping a reference to that cgroup, and the method name
for that is "put", so rename close_cgroup() to cgroup__put() to follow
this naming convention.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-sccxpnd7bgwc1llgokt6fcey@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Just to make this code look more like other places in tools/perf.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-j3j72vvn2d5j7tenlghdy195@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

That name isn't used, is shorter, lets switch to it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-e51yphwgvepd1y4f5fjptmjq@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The 'opt' parameter in parse_cgroups() _is_ used. The original patch
used '__used' that was even more confusing :-)

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 023695d9 ("perf tool: Add cgroup support")
Link: https://lkml.kernel.org/n/tip-4jo2puz0empkoou6bbq460tl@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Conflicts:
	tools/perf/perf.h
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'perf-urgent-for-mingo-4.16-20180306' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

- Be more robust when drawing arrows in the annotation TUI, avoiding a
  segfault when jump instructions have as a target addresses in functions
  other that the one currently being annotated. The full fix will come in
  the following days, when jumping to other functions will work as call
  instructions (Arnaldo Carvalho de Melo)

- Prevent auxtrace_queues__process_index() from queuing AUX area data for
  decoding when the --no-itrace option has been used (Adrian Hunter)

- Sync copy of kvm UAPI headers and x86's cpufeatures.h (Arnaldo Carvalho de Melo)

- Fix 'perf stat' CSV output format for non-supported counters (Ilya Pronin)

- Fix crash in 'perf record|perf report' pipe mode (Jiri Olsa)

- Fix annoying 'perf top' overwrite fallback message on older kernels (Kan Liang)

- Fix the usage on the 'perf kallsyms' man page (Sangwon Hong)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

trigger_on() means that the trigger is available but not ready, however
trigger_on() was making it ready. That can segfault if the signal comes
before trigger_ready(). e.g. (USR2 signal delivery not shown)

  $ perf record -e intel_pt//u -S sleep 1
  perf: Segmentation fault
  Obtained 16 stack frames.
  /home/ahunter/bin/perf(sighandler_dump_stack+0x40) [0x4ec550]
  /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
  /home/ahunter/bin/perf(perf_evsel__disable+0x26) [0x4b9dd6]
  /home/ahunter/bin/perf() [0x43a45b]
  /lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
  /lib/x86_64-linux-gnu/libc.so.6(__xstat64+0x15) [0x7fa7641d2cc5]
  /home/ahunter/bin/perf() [0x4ec6c9]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4ec73b]
  /home/ahunter/bin/perf() [0x4eca15]
  /home/ahunter/bin/perf(machine__create_kernel_maps+0x257) [0x4f0b77]
  /home/ahunter/bin/perf(perf_session__new+0xc0) [0x4f86f0]
  /home/ahunter/bin/perf(cmd_record+0x722) [0x43c132]
  /home/ahunter/bin/perf() [0x4a11ae]
  /home/ahunter/bin/perf(main+0x5d4) [0x427fb4]

Note, for testing purposes, this is hard to hit unless you add some sleep()
in builtin-record.c before record__open().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: stable@vger.kernel.org
Fixes: 3dcc4436 ("perf tools: Introduce trigger class")
Link: http://lkml.kernel.org/r/1519807144-30694-1-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Prevent auxtrace_queues__process_index() from queuing AUX area data for
decoding when the --no-itrace option has been used.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1520327598-1317-3-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When printing stats in CSV mode, 'perf stat' appends extra separators
when a counter is not supported:

<not supported>,,L1-dcache-store-misses,mesos/bd442f34-2b4a-47df-b966-9b281f9f56fc,0,100.00,,,,

Which causes a failure when parsing fields. The numbers of separators
should be the same for each line, no matter if the counter is or not
supported.
Signed-off-by: Ilya Pronin <ipronin@twitter.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/20180306064353.31930-1-xiyou.wangcong@gmail.com
Fixes: 92a61f64 ("perf stat: Implement CSV metrics output")
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Merge tag 'perf-core-for-mingo-4.17-20180305' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

- Be more robust when drawing arrows in the annotation TUI, avoiding a
  segfault when jump instructions have as a target addresses in functions
  other that the one currently being annotated. The full fix will come in
  the following days, when jumping to other functions will work as call
  instructions (Arnaldo Carvalho de Melo)

- Allow asking for the maximum allowed sample rate in 'top' and
  'record', i.e. 'perf record -F max' will read the
  kernel.perf_event_max_sample_rate sysctl and use it (Arnaldo Carvalho de Melo)

- When the user specifies a freq above kernel.perf_event_max_sample_rate,
  Throttle it down to that max freq, and warn the user about it, add as
  well --strict-freq so that the previous behaviour of not starting the
  session when the desired freq can't be used can be selected (Arnaldo Carvalho de Melo)

- Find 'call' instruction target symbol at parsing time, used so far in
  the TUI, part of the infrastructure changes that will end up allowing
  for jumps to navigate to other functions, just like 'call'
  instructions. (Arnaldo Carvalho de Melo)

- Use xyarray dimensions to iterate fds in 'perf stat' (Andi Kleen)

- Ignore threads for which the current user hasn't permissions when
  enabling system-wide --per-thread (Jin Yao)

- Fix some backtrace perf test cases to use 'perf record' + 'perf script'
  instead, till 'perf trace' starts using ordered_events or equivalent
  to avoid symbol resolving artifacts due to reordering of
  PERF_RECORD_MMAP events (Jiri Olsa)

- Fix crash in 'perf record' pipe mode, it needs to allocate the ID
  array even for a single event, unlike non-pipe mode (Jiri Olsa)

- Make annoying fallback message on older kernels with newer 'perf top'
  binaries trying to use overwrite mode and that not being present
  in the older kernels (Kan Liang)

- Switch last users of old APIs to the newer perf_mmap__read_event()
  one, then discard those old mmap read forward APIs (Kan Liang)

- Fix the usage on the 'perf kallsyms' man page (Sangwon Hong)

- Simplify cgroup arguments when tracking multiple events (weiping zhang)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

The changes in dd84441a ("x86/speculation: Use IBRS if available
before calling into firmware") don't need any kind of special treatment
in the current tools/perf/ codebase, so just update the copy to get rid
of the perf build warning:

  BUILD:   Doing 'make -j4' parallel build
  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-mzmuxocrf96v922xkerey3ns@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

In 801e459a ("KVM: x86: Add a framework for supporting MSR-based
features") a new ioctl was introduced, which with this sync of the kvm
UAPI headers, makes 'perf trace' know about it:

  $ cd /tmp/build/perf/trace/beauty/generated/ioctl/
  $ diff -u kvm_ioctl_array.c.old kvm_ioctl_array.c
  --- /tmp/kvm_ioctl_array.c	2018-03-05 11:55:38.409145056 -0300
  +++ /tmp/build/perf/trace/beauty/generated/ioctl/kvm_ioctl_array.c	2018-03-05 11:56:17.456153501 -0300
  @@ -6,6 +6,7 @@
 	[0x04] = "GET_VCPU_MMAP_SIZE",
 	[0x05] = "GET_SUPPORTED_CPUID",
 	[0x09] = "GET_EMULATED_CPUID",
  +	[0x0a] = "GET_MSR_FEATURE_INDEX_LIST",
 	[0x40] = "SET_MEMORY_REGION",
 	[0x41] = "CREATE_VCPU",
 	[0x42] = "GET_DIRTY_LOG",

So when using 'perf trace -e ioctl' that will appear along with the
others, like in this excerpt of a system wide session:

  14.556 ( 0.006 ms): CPU 0/KVM/16077 ioctl(fd: 19<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
  14.565 ( 0.006 ms): CPU 0/KVM/16077 ioctl(fd: 19<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) = 0
  14.573 (         ): CPU 0/KVM/16077 ioctl(fd: 19<anon_inode:kvm-vcpu:0>, cmd: KVM_RUN) ...
  34.075 ( 0.016 ms): gnome-shell/2192 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_BUSY, arg: 0x7ffe4e73e850) = 0
  40.549 ( 0.012 ms): gnome-shell/2192 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_BUSY, arg: 0x7ffe4e73ece0) = 0
  40.625 ( 0.005 ms): gnome-shell/2192 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_BUSY, arg: 0x7ffe4e73e940) = 0
  40.632 ( 0.003 ms): gnome-shell/2192 ioctl(fd: 8</dev/dri/card0>, cmd: DRM_I915_GEM_MADVISE, arg: 0x7ffe4e73e9b0) = 0

This also silences the perf build header copy drift verifier:

  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j4' parallel build
  Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-h31oz5g0mt1dh2s2ajq6o6no@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Currently we can crash perf record when running in pipe mode, like:

  $ perf record ls | perf report
  # To display the perf.data header info, please use --header/--header-only options.
  #
  perf: Segmentation fault
  Error:
  The - file has no samples!

The callstack of the crash is:

    0x0000000000515242 in perf_event__synthesize_event_update_name
  3513            ev = event_update_event__new(len + 1, PERF_EVENT_UPDATE__NAME, evsel->id[0]);
  (gdb) bt
  #0  0x0000000000515242 in perf_event__synthesize_event_update_name
  #1  0x00000000005158a4 in perf_event__synthesize_extra_attr
  #2  0x0000000000443347 in record__synthesize
  #3  0x00000000004438e3 in __cmd_record
  #4  0x000000000044514e in cmd_record
  #5  0x00000000004cbc95 in run_builtin
  #6  0x00000000004cbf02 in handle_internal_command
  #7  0x00000000004cc054 in run_argv
  #8  0x00000000004cc422 in main

The reason of the crash is that the evsel does not have ids array
allocated and the pipe's synthesize code tries to access it.

We don't force evsel ids allocation when we have single event, because
it's not needed. However we need it when we are in pipe mode even for
single event as a key for evsel update event.

Fixing this by forcing evsel ids allocation event for single event, when
we are in pipe mode.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180302161354.30192-1-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This first happened with a gcc function, _cpp_lex_token, that has the
usual jumps:

 │1159e6c: ↓ jne    115aa32 <_cpp_lex_token@@Base+0xf92>

I.e. jumps to a label inside that function (_cpp_lex_token), and those
works, but also this kind:

 │1159e8b: ↓ jne    c469be <cpp_named_operator2name@@Base+0xa72>

I.e. jumps to another function, outside _cpp_lex_token, which are not
being correctly handled generating as a side effect references to
ab->offset[] entries that are set to NULL, so to make this code more
robust, check that here.

A proper fix for will be put in place, looking at the function name
right after the '<' token and probably treating this like a 'call'
instruction.

For now just don't draw the arrow.
Reported-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Link: https://lkml.kernel.org/n/tip-5tzvb875ep2sel03aeefgmud@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

On older (e.g. v4.4) kernels, an annoying fallback message can be
observed in 'perf top':

	┌─Warning:──────────────────────┐
	│fall back to non-overwrite mode│
	│                               │
	│                               │
	│Press any key...               │
	└───────────────────────────────┘

The 'perf top' utility has been changed to overwrite mode since commit
ebebbf08 ("perf top: Switch default mode to overwrite mode").

For older kernels which don't have overwrite mode support, 'perf top'
will fall back to non-overwrite mode and print out the fallback message
using ui__warning(), which needs user's input to close.

The fallback message is not critical for end users. Turning it to debug
message which is printed when running with -vv.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Fixes: ebebbf08 ("perf top: Switch default mode to overwrite mode")
Link: http://lkml.kernel.org/r/1519669030-176549-1-git-send-email-kan.liang@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

First, all man pages highlight only perf and subcommands except 'perf
kallsyms', which includes the full usage. Fix it for commands to
monopolize underlines.

Second, options can be ommited when executing 'perf kallsyms', so add
square brackets between <option>.
Signed-off-by: Sangwon Hong <qpakzk@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/r/1518377864-20353-1-git-send-email-qpakzk@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Discards legacy interfaces perf_evlist__mmap_read_forward(),
perf_evlist__mmap_read() and perf_evlist__mmap_consume().

No tools use them.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-14-git-send-email-kan.liang@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'task-exit' still use the legacy interface.

No functional change.

Committer notes:

Testing it:

  # perf test exit
  21: Number of exit events of a simple workload            : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-13-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'switch-tracking' still use the legacy interface.

No functional change.

Committer testing:

  # perf test switch
  32: Track with sched_switch                               : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-12-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'sw-clock' still use the legacy interface.

No functional change.

Committer testing:

  # perf test clock
  22: Software clock events period values                   : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-11-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'time-to-tsc' still use the legacy interface.

No functional change.

Commiter notes:

Testing it:

  # perf test tsc
  57: Convert perf time to TSC                              : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-10-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'perf-record' still use the legacy interface.

No functional change.

Committer notes:

Testing it:

  # perf test PERF_RECORD
   8: PERF_RECORD_* events & perf_sample fields             : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-9-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'syscalls:sys_enter_openat event fields' still use the
legacy interface.

No functional change.

Committer notes:

Testing it:

  # perf test sys_enter_openat
  15: syscalls:sys_enter_openat event fields                : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-8-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'mmap-basic' still use the legacy interface.

No functional change.

Committer notes:

Testing it:

  # perf test "mmap interface"
   4: Read samples using the mmap interface                 : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-7-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'keep tracking' still use the legacy interface.

No functional change.

Committer testing:

  # perf test tracking
  25: Use a dummy software event to keep tracking           : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-6-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'object code reading' still use the legacy interface.

No functional change.

Committer notes:

Testing:

  # perf test reading
  23: Object code reading: Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-5-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf test 'bpf' still use the legacy interface.

No functional change.

Committer notes:

Tested with:

  # perf test bpf
  39: BPF filter                                            :
  39.1: Basic BPF filtering                                 : Ok
  39.2: BPF pinning                                         : Ok
  39.3: BPF prologue generation                             : Ok
  39.4: BPF relocation checker                              : Ok
  #
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-4-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The perf python binding still use the legacy interface.

No functional change.

Committer notes:

Tested before and after with:

  [root@jouet perf]# export PYTHONPATH=/tmp/build/perf/python
  [root@jouet perf]# tools/perf/python/twatch.py
  cpu: 0, pid: 1183, tid: 6293 { type: exit, pid: 1183, ppid: 1183, tid: 6293, ptid: 6293, time: 17886646588257}
  cpu: 2, pid: 13820, tid: 13820 { type: fork, pid: 13820, ppid: 13820, tid: 6306, ptid: 13820, time: 17886869099529}
  cpu: 1, pid: 13820, tid: 6306 { type: comm, pid: 13820, tid: 6306, comm: TaskSchedulerFo }
  ^CTraceback (most recent call last):
    File "tools/perf/python/twatch.py", line 68, in <module>
      main()
    File "tools/perf/python/twatch.py", line 40, in main
      evlist.poll(timeout = -1)
  KeyboardInterrupt
  [root@jouet perf]#

No problems found.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-3-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The 'perf trace' utility still use the legacy interface.

Switch to the new perf_mmap__read_event() interface.

No functional change.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1519945751-37786-2-git-send-email-kan.liang@linux.intel.com
[ Changed bool parameters from 0 to 'false', as per Jiri comment ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>