Some distros put -fstack-protector-strong in the compiler flags to be
used to build python extensions, but then, the clang version in that
distro doesn't know about that, only gcc does.

Check if that is the case and remove it from the set of options used to
build the python binding with clang.

Case at hand:

oraclelinux:7

  $ head -2 /etc/os-release
  NAME="Oracle Linux Server"
  VERSION="7.6"
  $ grep stack-protector /usr/lib64/python2.7/_sysconfigdata.py | head -1 | cut -c-120
 'CFLAGS': '-fno-strict-aliasing -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --para
  $
  gcc version 4.8.5 20150623 (Red Hat 4.8.5-36.0.1) (GCC)
  clang version 3.4.2 (tags/RELEASE_34/dot2-final)

  clang: error: unknown argument: '-fstack-protector-strong'
  clang: error: unknown argument: '-fstack-protector-strong'
  error: command 'clang' failed with exit status 1
  cp: cannot stat '/tmp/build/perf/python_ext_build/lib/perf*.so': No such file or directory
  make[2]: *** [/tmp/build/perf/python/perf.so] Error 1

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-brmp2415zxpbhz45etkgjoma@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Return NULL instead of null-terminating version char array when fgets
fails due to end-of-file or error.
Signed-off-by: NDonald Yandt <donald.yandt@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Fixes: 30ba5b0e ("perf machine: Null-terminate version char array upon fgets(/proc/version) error")
Link: http://lkml.kernel.org/r/20190528134128.30841-1-donald.yandt@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Bumping it from just 4:

Before:

  $ perf -v
  perf version 5.2.rc1.g80978f
  $

After:

  $ perf -v
  perf version 5.2.rc1.g80978fc864c5
  $
Requested-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-p4yun2nxlo7eeeohyx5v4kw7@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There's no need to display "ksymbol event with" text for the
PERF_RECORD_KSYMBOL event and "bpf event with" test for the
PERF_RECORD_BPF_EVENT event.

Remove it so it also goes along with other side-band events display.

Before:

  # perf script --show-bpf-events
  ...
  swapper     0 [000]     0.000000: PERF_RECORD_KSYMBOL ksymbol event with addr ffffffffc0ef971d len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
  swapper     0 [000]     0.000000: PERF_RECORD_BPF_EVENT bpf event with type 1, flags 0, id 36

After:

  # perf script --show-bpf-events
  ...
  swapper     0 [000]     0.000000: PERF_RECORD_KSYMBOL addr ffffffffc0ef971d len 229 type 1 flags 0x0 name bpf_prog_2a142ef67aaad174
  swapper     0 [000]     0.000000: PERF_RECORD_BPF_EVENT type 1, flags 0, id 36
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-12-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add map_groups__merge_in test to test the map_groups__merge_in function
usage - merging kcore maps into existing eBPF maps.

Committer testing:

  # perf test merge
  59: map_groups__merge_in                                  : Ok
  # perf test -v merge
  59: map_groups__merge_in                                  :
  --- start ---
  test child forked, pid 8349
  test child finished with 0
  ---- end ----
  map_groups__merge_in: Ok
  #
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-10-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Pad the DSO name in --call-trace so we don't have the indent screwed by
different DSO name lengths, as now for kernel there's also BPF code
displayed.

  # perf-with-kcore record pt -e intel_pt//ku -- sleep 1
  # perf-core/perf-with-kcore script pt --call-trace

Before:

   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                      kretprobe_perf_func
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                          trace_call_bpf
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                              __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                                  __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_get_current_pid_tgid
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_ktime_get_ns
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms])                                          __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms])                                              __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806465045: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         __htab_map_lookup_elem
   sleep 3660 [16] 57036.806465366: ([kernel.kallsyms])                                          memcmp
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                          probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                                  check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                          probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                                  check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_get_current_uid_gid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms])                                          from_kgid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms])                                          from_kuid
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                          perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                              perf_prepare_sample
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                                  perf_misc_flags
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                                      __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                                          __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806466328: ([kvm])                                                      kvm_is_in_guest
   sleep 3660 [16] 57036.806466649: ([kernel.kallsyms])                                                  __perf_event_header__init_id.isra.0
   sleep 3660 [16] 57036.806466649: ([kernel.kallsyms])                                              perf_output_begin

After:

   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )     kretprobe_perf_func
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )         trace_call_bpf
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )             __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )                 __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_get_current_pid_tgid
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_ktime_get_ns
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms]                      )                         __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms]                      )                             __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806465045: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     __htab_map_lookup_elem
   sleep 3660 [16] 57036.806465366: ([kernel.kallsyms]                      )                         memcmp
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                         probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                                 check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                         probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                                 check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_get_current_uid_gid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms]                      )                         from_kgid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms]                      )                         from_kuid
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                         perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                             perf_prepare_sample
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                                 perf_misc_flags
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                                     __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                                         __x86_indirect_thunk_rax
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-8-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add BPF related code into DSO reading paths to return size (bpf_size)
and read the BPF code (bpf_read).
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-5-jolsa@kernel.org
[ Use uintptr_t when casting from u64 to u8 pointers ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There's no need for the while loop now, also we can connect two (ret >
0) condition legs together.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-4-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Move the file specific code in the dso_cache__read function to a
separate file_read function. I'll add BPF specific code in the following
patches.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-3-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Moving file specific code in dso__data_file_size function into separate
file_size function. I'll add bpf specific code in following patches.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-2-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The namespaces and comm fields of a thread are protected by rwsem and
require write access for it.  So it ended up using a cast to remove
the const qualifier.  Let's get rid of the const then.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Link: http://lkml.kernel.org/r/20190527061149.168640-1-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We need to preserve eBPF maps even if they are covered by kcore, because
we need to access eBPF dso for source data.

Add the map_groups__merge_in function to do that.  It merges a map into
map_groups by splitting the new map within the existing map regions.
Suggested-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-9-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With pgoff set to zero, the map__map_ip function will return BPF
addresses based from 0, which is what we need when we read the data from
a BPF DSO.

Adding BPF symbols with mapped IP addresses as well.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-7-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Commit 4eb06815 ("perf script: Make itrace script default to all
calls") does not work for the case when '--itrace' only is used, because
default_no_sample is not being passed.

Example:

 Before:

  $ perf record -e intel_pt/cyc/u ls
  $ perf script --itrace > cmp1.txt
  $ perf script --itrace=cepwx > cmp2.txt
  $ diff -sq cmp1.txt cmp2.txt
  Files cmp1.txt and cmp2.txt differ

 After:

  $ perf script --itrace > cmp1.txt
  $ perf script --itrace=cepwx > cmp2.txt
  $ diff -sq cmp1.txt cmp2.txt
  Files cmp1.txt and cmp2.txt are identical
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 4eb06815 ("perf script: Make itrace script default to all calls")
Link: http://lkml.kernel.org/r/20190520113728.14389-3-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Commit 4eb06815 ("perf script: Make itrace script default to all
calls") does not work because 'use_browser' is being used to determine
whether to default to periodic sampling (i.e. better for perf report).
The result is that nothing but CBR events display for perf script when
no --itrace option is specified.

Fix by using 'default_no_sample' and 'inject' instead.

Example:

 Before:

  $ perf record -e intel_pt/cyc/u ls
  $ perf script > cmp1.txt
  $ perf script --itrace=cepwx > cmp2.txt
  $ diff -sq cmp1.txt cmp2.txt
  Files cmp1.txt and cmp2.txt differ

 After:

  $ perf script > cmp1.txt
  $ perf script --itrace=cepwx > cmp2.txt
  $ diff -sq cmp1.txt cmp2.txt
  Files cmp1.txt and cmp2.txt are identical
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.20+
Fixes: 90e457f7 ("perf tools: Add Intel PT support")
Link: http://lkml.kernel.org/r/20190520113728.14389-2-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We mark the end of kernel based on the first module, but that could
cover some bpf program maps. Reading _etext symbol if it's present to
get precise kernel map end.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Acked-by: NSong Liu <songliubraving@fb.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-6-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

In case it's recorded in a different arch.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> <hbathini@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Fixes: f3b3614a ("perf tools: Add PERF_RECORD_NAMESPACES to include namespaces related info")
Link: http://lkml.kernel.org/r/20190522053250.207156-3-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It seems that the current code lacks holding the namespace lock in
thread__namespaces().  Otherwise it can see inconsistent results.
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Link: http://lkml.kernel.org/r/20190522053250.207156-2-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This strncat() is safe because the buffer was allocated with zalloc(),
however gcc doesn't know that. Since the string always has 4 non-null
bytes, just use memcpy() here.

    CC       /home/shawn/linux/tools/perf/util/data-convert-bt.o
  In file included from /usr/include/string.h:494,
                   from /home/shawn/linux/tools/lib/traceevent/event-parse.h:27,
                   from util/data-convert-bt.c:22:
  In function ‘strncat’,
      inlined from ‘string_set_value’ at util/data-convert-bt.c:274:4:
  /usr/include/powerpc64le-linux-gnu/bits/string_fortified.h:136:10: error: ‘__builtin_strncat’ output may be truncated copying 4 bytes from a string of length 4 [-Werror=stringop-truncation]
    136 |   return __builtin___strncat_chk (__dest, __src, __len, __bos (__dest));
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: NShawn Landden <shawn@git.icu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
LPU-Reference: 20190518183238.10954-1-shawn@git.icu
Link: https://lkml.kernel.org/n/tip-289f1jice17ta7tr3tstm9jm@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With this patch, we can use the 'percore' event qualifier in perf-stat.

  root@skl:/tmp# perf stat -e cpu/event=0,umask=0x3,percore=1/,cpu/event=0,umask=0x3/ -a -A -I1000
    1.000773050 S0-C0   98,352,832 cpu/event=0,umask=0x3,percore=1/  (50.01%)
    1.000773050 S0-C1  103,763,057 cpu/event=0,umask=0x3,percore=1/  (50.02%)
    1.000773050 S0-C2  196,776,995 cpu/event=0,umask=0x3,percore=1/  (50.02%)
    1.000773050 S0-C3  176,493,779 cpu/event=0,umask=0x3,percore=1/  (50.02%)
    1.000773050 CPU0    47,699,641 cpu/event=0,umask=0x3/            (50.02%)
    1.000773050 CPU1    49,052,451 cpu/event=0,umask=0x3/            (49.98%)
    1.000773050 CPU2   102,771,422 cpu/event=0,umask=0x3/            (49.98%)
    1.000773050 CPU3   100,784,662 cpu/event=0,umask=0x3/            (49.98%)
    1.000773050 CPU4    43,171,342 cpu/event=0,umask=0x3/            (49.98%)
    1.000773050 CPU5    54,152,158 cpu/event=0,umask=0x3/            (49.98%)
    1.000773050 CPU6    93,618,410 cpu/event=0,umask=0x3/            (49.98%)
    1.000773050 CPU7    74,477,589 cpu/event=0,umask=0x3/            (49.99%)

In this example, we count the event 'ref-cycles' per-core and per-CPU in
one perf stat command-line. From the output, we can see:

  S0-C0 = CPU0 + CPU4
  S0-C1 = CPU1 + CPU5
  S0-C2 = CPU2 + CPU6
  S0-C3 = CPU3 + CPU7

So the result is expected (tiny difference is ignored).

Note that, the 'percore' event qualifier needs to use with option '-A'.
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Tested-by: NRavi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1555077590-27664-4-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Move the aggregate counts printing to a new function
print_counter_aggrdata, which will be used in following patches.
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Tested-by: NRavi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1555077590-27664-3-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add a 'percore' event qualifier, like cpu/event=0,umask=0x3,percore=1/,
that sums up the event counts for both hardware threads in a core.

We can already do this with --per-core, but it's often useful to do
this together with other metrics that are collected per hardware thread.
So we need to support this per-core counting on a event level.

This can be implemented in only the user tool, no kernel support needed.

 v4:
 ---
 1. Add Arnaldo's patch which updates the documentation for
    this new qualifier.
 2. Rebase to latest perf/core branch

 v3:
 ---
 Simplify the code according to Jiri's comments.
 Before:
   "return term->val.percore ? true : false;"
 Now:
   "return term->val.percore;"

 v2:
 ---
 Change the qualifier name from 'coresum' to 'percore' according to
 comments from Jiri and Andi.
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Tested-by: NRavi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1555077590-27664-2-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The sample timestamp is updated to ensure that the timestamp represents
the time of the sample and not a branch that the decoder is still
walking towards. The sample timestamp is updated when the decoder
returns, but the decoder does not return for non-taken branches. Update
the sample timestamp then also.

Note that commit 3f04d98e ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 3f04d98e ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-4-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The decoder uses its current timestamp in samples. Usually that is a
timestamp that has already passed, but in some cases it is a timestamp
for a branch that the decoder is walking towards, and consequently
hasn't reached.

The intel_pt_sample_time() function decides which is which, but was not
handling TNT packets exactly correctly.

In the case of TNT, the timestamp applies to the first branch, so the
decoder must first walk to that branch.

That means intel_pt_sample_time() should return true for TNT, and this
patch makes that change. However, if the first branch is a non-taken
branch (i.e. a 'N'), then intel_pt_sample_time() needs to return false
for subsequent taken branches in the same TNT packet.

To handle that, introduce a new state INTEL_PT_STATE_TNT_CONT to
distinguish the cases.

Note that commit 3f04d98e ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: 3f04d98e ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-3-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The timestamp used to determine if an instruction sample is made, is an
estimate based on the number of instructions since the last known
timestamp. A consequence is that it might go backwards, which results in
extra samples. Change it so that a sample is only made when the
timestamp goes forwards.

Note this does not affect a sampling period of 0 or sampling periods
specified as a count of instructions.

Example:

 Before:

 $ perf script --itrace=i10us
 ls 13812 [003] 2167315.222583:       3270 instructions:u:      7fac71e2e494 __GI___tunables_init+0xf4 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:      30902 instructions:u:      7fac71e2da0f _dl_cache_libcmp+0x2f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:         10 instructions:u:      7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:          8 instructions:u:      7fac71e2d9ea _dl_cache_libcmp+0xa (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:         14 instructions:u:      7fac71e2d9ea _dl_cache_libcmp+0xa (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:          6 instructions:u:      7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:         14 instructions:u:      7fac71e2d9ff _dl_cache_libcmp+0x1f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:          4 instructions:u:      7fac71e2dab2 _dl_cache_libcmp+0xd2 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222728:      16423 instructions:u:      7fac71e2477a _dl_map_object_deps+0x1ba (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222734:      12731 instructions:u:      7fac71e27938 _dl_name_match_p+0x68 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ...

 After:
 $ perf script --itrace=i10us
 ls 13812 [003] 2167315.222583:       3270 instructions:u:      7fac71e2e494 __GI___tunables_init+0xf4 (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222667:      30902 instructions:u:      7fac71e2da0f _dl_cache_libcmp+0x2f (/lib/x86_64-linux-gnu/ld-2.28.so)
 ls 13812 [003] 2167315.222728:      16479 instructions:u:      7fac71e2477a _dl_map_object_deps+0x1ba (/lib/x86_64-linux-gnu/ld-2.28.so)
 ...
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Fixes: f4aa0819 ("perf tools: Add Intel PT decoder")
Link: http://lkml.kernel.org/r/20190510124143.27054-2-adrian.hunter@intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There may be different register mask for use with intr or user on some
platforms, e.g. Icelake.

Add weak functions arch__intr_reg_mask() and arch__user_reg_mask() to
return intr and user register mask respectively.

Check mask before printing or comparing the register name.

Generic code always return PERF_REGS_MASK. No functional change.
Suggested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NKan Liang <kan.liang@linux.intel.com>
Tested-by: NRavi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1557865174-56264-2-git-send-email-kan.liang@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The available registers for --int-regs and --user-regs may be different,
e.g. XMM registers.

Split parse_regs into two dedicated functions for --int-regs and
--user-regs respectively.

Modify the warning message. "--user-regs=?" should be applied to show
the available registers for --user-regs.
Signed-off-by: NKan Liang <kan.liang@linux.intel.com>
Tested-by: NRavi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1557865174-56264-1-git-send-email-kan.liang@linux.intel.com
[ Changed docs as suggested by Ravi and agreed by Kan ]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

zstd_init(, comp_level = 0) initializes decompression part of API only
hat now consists of zstd_decompress_stream() function.

The perf.data PERF_RECORD_COMPRESSED records are decompressed using
zstd_decompress_stream() function into a linked list of mmaped memory
regions of mmap_comp_len size (struct decomp).

After decompression of one COMPRESSED record its content is iterated and
fetched for usual processing. The mmaped memory regions with
decompressed events are kept in the linked list till the tool process
termination.

When dumping raw records (e.g., perf report -D --header) file offsets of
events from compressed records are printed as zero.

Committer notes:

Since now we have support for processing PERF_RECORD_COMPRESSED, we see
none, in raw form, like we saw in the previous patch commiter notes,
they were decompressed into the usual PERF_RECORD_{FORK,MMAP,COMM,etc}
records, we only see the stats for those PERF_RECORD_COMPRESSED events,
and since I used the file generated in the commiter notes for the
previous patch, there they are, 2 compressed records:

  $ perf report --header-only | grep cmdline
  # cmdline : /home/acme/bin/perf record -z2 sleep 1
  $ perf report -D | grep COMPRESS
        COMPRESSED events:          2
        COMPRESSED events:          0
  $ perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 15  of event 'cycles:u'
  # Event count (approx.): 962227
  #
  # Overhead  Command  Shared Object     Symbol
  # ........  .......  ................  ...........................
  #
      46.99%  sleep    libc-2.28.so      [.] _dl_addr
      29.24%  sleep    [unknown]         [k] 0xffffffffaea00a67
      16.45%  sleep    libc-2.28.so      [.] __GI__IO_un_link.part.1
       5.92%  sleep    ld-2.28.so        [.] _dl_setup_hash
       1.40%  sleep    libc-2.28.so      [.] __nanosleep
       0.00%  sleep    [unknown]         [k] 0xffffffffaea00163

  #
  # (Tip: To see callchains in a more compact form: perf report -g folded)
  #
  $
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/304b0a59-942c-3fe1-da02-aa749f87108b@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Committer note:

Split from a larger patch, this only dumps PERF_RECORD_COMPRESSED as
unhandled, so that when we introduce the record part in the next patch,
we don't see unhandled events when using 'perf record -D'.

Changed it so that we dump the event if the handler is just a stub, i.e.
for the case where we don't have ZSTD linked but we're processing a
perf.data file generated by a tool with that linked.

Also when failing to decompress we can't just dump the uncompressed
event and return 0, we have to propagate the error.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/304b0a59-942c-3fe1-da02-aa749f87108b@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Compression is implemented using the functions from zstd.c. As the memory
to operate on the compression uses mmap->aio.data[] buffers. If Zstd
streaming compression API fails for some reason the data to be compressed
are just copied into the memory buffers using plain memcpy().

Compressed trace frame consists of an array of PERF_RECORD_COMPRESSED
records. Each element of the array is not longer that PERF_SAMPLE_MAX_SIZE
and consists of perf_event_header followed by the compressed chunk
that is decompressed on the loading stage.

perf_mmap__aio_push() is replaced by perf_mmap__push() which is now used
in the both serial and AIO streaming cases. perf_mmap__push() is extended
with positive return values to signify absence of data ready for
processing.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/77db2b2c-5d03-dbb0-aeac-c4dd92129ab9@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Compression is implemented using the functions from zstd.c. As the
memory to operate on the compression uses mmap->data buffer.

If Zstd streaming compression API fails for some reason the data to be
compressed are just copied into the memory buffers using plain memcpy().

Compressed trace frame consists of an array of PERF_RECORD_COMPRESSED
records. Each element of the array is not longer that
PERF_SAMPLE_MAX_SIZE and consists of perf_event_header followed by the
compressed chunk that is decompressed on the loading stage.

Comitter notes:

Undo some unnecessary line breaks, remove some unnecessary () around
zstd_data to then just get its address, and fix conflicts with
BPF_PROG_INFO/BPF_BTF patchkits.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/744df43f-3932-2594-ddef-1e99a3cad03a@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Implemented functions are based on Zstd streaming compression API.

The functions are used in runtime to compress data that come from mmaped
kernel buffer. zstd_init(), zstd_fini() are used for initialization and
finalization to allocate and deallocate internal zstd objects.
zstd_compress_stream_to_records() is used to convert parts of mmaped
kernel buffer into an array of PERF_RECORD_COMPRESSED records.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/18bf36f3-b85a-1fe2-dd83-10e0c6069568@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Implemented mmap data buffer that is used as the memory to operate
on when compressing data in case of serial trace streaming.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/49b31321-0f70-392b-9a4f-649d3affe090@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Implemented PERF_RECORD_COMPRESSED event, related data types, header
feature and functions to write, read and print feature attributes from
the trace header section.

comp_mmap_len preserves the size of mmaped kernel buffer that was used
during collection. comp_mmap_len size is used on loading stage as the
size of decomp buffer for decompression of COMPRESSED events content.

Committer notes:

Fixed up conflict with BPF_PROG_INFO and BTF_BTF header features.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/ebbaf031-8dda-3864-ebc6-7922d43ee515@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Define 'bytes_transferred' and 'bytes_compressed' metrics to calculate
ratio in the end of the data collection:

	compression ratio = bytes_transferred / bytes_compressed

The 'bytes_transferred' metric accumulates the amount of bytes that was
extracted from the mmaped kernel buffers for compression, while
'bytes_compressed' accumulates the amount of bytes that was received
after applying compression.
Signed-off-by: NAlexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1d4bf499-cb03-26dc-6fc6-f14fec7622ce@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If fgets() fails due to any other error besides end-of-file, the version
char array may not even be null-terminated.
Signed-off-by: NDonald Yandt <donald.yandt@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Fixes: a1645ce1 ("perf: 'perf kvm' tool for monitoring guest performance from host")
Link: http://lkml.kernel.org/r/20190514110100.22019-1-donald.yandt@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Icelake and later platforms support collecting XMM registers with PEBS
event.

Add support for 'perf script' to dump them, and support for the register
parser in 'perf record -I=' ... to configure them.

For now they are just printed in hex, we could potentially later add
other formats too.

Committer testing:

Before:

  # perf record -IXMM0
  Warning:
  unknown register XMM0, check man page or run 'perf record -I?'

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

  #
  # perf record -I?
  available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11 R12 R13 R14 R15

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]
  #

After:

  # perf record -IXMM0
  Error:
  The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (cycles).
  /bin/dmesg | grep -i perf may provide additional information.

  #
  # perf record -I?
  available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11 R12 R13 R14 R15 XMM0 XMM1 XMM2 XMM3 XMM4 XMM5 XMM6 XMM7 XMM8 XMM9 XMM10 XMM11 XMM12 XMM13 XMM14 XMM15

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -I, --intr-regs[=<any register>]
                            sample selected machine registers on interrupt, use -I ? to list register names
  #

More work is needed to, when faced with such error, warn the user that
that register is not available on the running platform.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190506141926.13659-1-kan.liang@linux.intel.comSigned-off-by: NKan Liang <kan.liang@linux.intel.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add quotes around the register name and suggest using 'perf record -I?'
to get the list of available registers.

Before:

  # perf record -Idi,xmm20,xmm1
  Warning:
  unknown register xmm20, check man page

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -I, --intr-regs[=<any register>]
                            sample selected machine registers on interrupt, use -I ? to list register names
  #
  # perf record -Idi,xmm20,xmm1
  Warning:
  unknown register "xmm20", check man page or run "perf record -I?"

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -I, --intr-regs[=<any register>]
                            sample selected machine registers on interrupt, use -I ? to list register names
  #

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lkml.kernel.org/n/tip-9a9hyuum8c0oggg86xd3sxc5@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When compiled with libunwind, perf does some preparatory work when
processing side-band events. This is not needed when report actually
don't unwind dwarf callchains, so it's disabled with
dwarf_callchain_users bool.

However we could move that check to higher level and shield more
unwanted code for normal report processing, giving us following speed up
on kernel build profile:

Before:

  $ perf record make -j40
  ...
  $ ll ../../perf.data
  -rw-------. 1 jolsa jolsa 461783932 Apr 26 09:11 perf.data
  $ perf stat -e cycles:u,instructions:u perf report -i perf.data > out

   Performance counter stats for 'perf report -i perf.data':

    78,669,920,155      cycles:u
    99,076,431,951      instructions:u            #    1.26  insn per cycle

      55.382823668 seconds time elapsed

      27.512341000 seconds user
      27.712871000 seconds sys

After:

  $ perf stat -e cycles:u,instructions:u perf report -i perf.data > out

   Performance counter stats for 'perf report -i perf.data':

    59,626,798,904      cycles:u
    88,583,575,849      instructions:u            #    1.49  insn per cycle

      21.296935559 seconds time elapsed

      20.010191000 seconds user
       1.202935000 seconds sys

The speed is higher with profile having many side-band events,
because these trigger libunwind preparatory code.

This does not apply for perf compiled with libdw for dwarf unwind,
only for build with libunwind.
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190426073804.17238-1-jolsa@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The hist__account_cycles() function is executed when the
hist_iter__branch_callback() is called.

But it looks it's not necessary.  In hist__account_cycles, it already
walks on all branch entries.

This patch moves the hist__account_cycles out of callback, now the data
processing is much faster than before.

Previous code has an issue that the ch[offset].num++ (in
__symbol__account_cycles) is executed repeatedly since
hist__account_cycles is called in each hist_iter__branch_callback, so
the counting of ch[offset].num is not correct (too big).

With this patch, the issue is fixed. And we don't need the code of
"ch->reset >= ch->num / 2" to check if there are too many overlaps (in
annotation__count_and_fill), otherwise some data would be hidden.

Now, we can try, for example:

  perf record -b ...
  perf annotate or perf report -s symbol

The before/after output should be no change.

 v3:
 ---
 Fix the crash in stdio mode.
 Like previous code, it needs the checking of ui__has_annotation()
 before hist__account_cycles()

 v2:
 ---
 1. Cover the similar perf report
 2. Remove the checking code "ch->reset >= ch->num / 2"
Signed-off-by: NJin Yao <yao.jin@linux.intel.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1552684577-29041-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>