Commit Graph

915446 Commits

Author SHA1 Message Date
Kan Liang
680d125cd5 perf script: Add option to enable the LBR stitching approach
With the LBR stitching approach, the reconstructed LBR call stack can
break the HW limitation. However, it may reconstruct invalid call stacks
in some cases, e.g. exception handing such as setjmp/longjmp.  Also, it
may impact the processing time especially when the number of samples
with stitched LBRs are huge.

Add an option to enable the approach.

Committer testing:

Using the same perf.data as with the latest cset committer testing
section:

  $ perf script --stitch-lbr
  <SNIP>
  tchain_edit 11131 15164.984292:     437491 cycles:u:
                    401106 f43+0x0 (/wb/tchain_edit)
                    40114c f42+0x18 (/wb/tchain_edit)
                    401172 f41+0xe (/wb/tchain_edit)
                    401194 f40+0x0 (/wb/tchain_edit)
                    40119b f39+0x0 (/wb/tchain_edit)
                    4011a2 f38+0x0 (/wb/tchain_edit)
                    4011a9 f37+0x0 (/wb/tchain_edit)
                    4011b0 f36+0x0 (/wb/tchain_edit)
                    4011b7 f35+0x0 (/wb/tchain_edit)
                    4011be f34+0x0 (/wb/tchain_edit)
                    4011c5 f33+0x0 (/wb/tchain_edit)
                    4011cc f32+0x0 (/wb/tchain_edit)
                    401207 f31+0x34 (/wb/tchain_edit)
                    401212 f30+0x0 (/wb/tchain_edit)
                    401219 f29+0x0 (/wb/tchain_edit)
                    401220 f28+0x0 (/wb/tchain_edit)
                    401227 f27+0x0 (/wb/tchain_edit)
                    40122e f26+0x0 (/wb/tchain_edit)
                    401235 f25+0x0 (/wb/tchain_edit)
                    40123c f24+0x0 (/wb/tchain_edit)
                    401243 f23+0x0 (/wb/tchain_edit)
                    40124a f22+0x0 (/wb/tchain_edit)
                    401251 f21+0x0 (/wb/tchain_edit)
                    401258 f20+0x0 (/wb/tchain_edit)
                    40125f f19+0x0 (/wb/tchain_edit)
                    401266 f18+0x0 (/wb/tchain_edit)
                    40126d f17+0x0 (/wb/tchain_edit)
                    401274 f16+0x0 (/wb/tchain_edit)
                    40127b f15+0x0 (/wb/tchain_edit)
                    401282 f14+0x0 (/wb/tchain_edit)
                    401289 f13+0x0 (/wb/tchain_edit)
                    401290 f12+0x0 (/wb/tchain_edit)
                    401297 f11+0x0 (/wb/tchain_edit)
                    40129e f10+0x0 (/wb/tchain_edit)
                    4012a5 f9+0x0 (/wb/tchain_edit)
                    4012ac f8+0x0 (/wb/tchain_edit)
                    4012b3 f7+0x0 (/wb/tchain_edit)
                    4012ba f6+0x0 (/wb/tchain_edit)
                    4012c1 f5+0x0 (/wb/tchain_edit)
                    4012c8 f4+0x0 (/wb/tchain_edit)
                    4012cf f3+0x0 (/wb/tchain_edit)
                    4012d6 f2+0x0 (/wb/tchain_edit)
                    4012dd f1+0x0 (/wb/tchain_edit)
                    4012e4 main+0x0 (/wb/tchain_edit)
              7f41a5016f41 __libc_start_main+0xf1 (/usr/lib64/libc-2.29.so)
  <SNIP>
  $

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-15-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
b1d1429b18 perf report: Add option to enable the LBR stitching approach
With the LBR stitching approach, the reconstructed LBR call stack can
break the HW limitation. However, it may reconstruct invalid call stacks
in some cases, e.g. exception handing such as setjmp/longjmp.  Also, it
may impact the processing time especially when the number of samples
with stitched LBRs are huge.

Add an option to enable the approach.

  # To display the perf.data header info, please use
  # --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 6K of event 'cycles'
  # Event count (approx.): 6492797701
  #
  # Children      Self  Command          Shared Object       Symbol
  # ........  ........  ...............  ..................
  # .................................
  #
    99.99%    99.99%  tchain_edit      tchain_edit        [.] f43
            |
            ---main
               f1
               f2
               f3
               f4
               f5
               f6
               f7
               f8
               f9
               f10
               f11
               f12
               f13
               f14
               f15
               f16
               f17
               f18
               f19
               f20
               f21
               f22
               f23
               f24
               f25
               f26
               f27
               f28
               f29
               f30
               f31
               |
                --99.65%--f32
                          f33
                          f34
                          f35
                          f36
                          f37
                          f38
                          f39
                          f40
                          f41
                          f42
                          f43

Committer testing:

  $ perf record --call-graph lbr /wb/tchain_edit
  [ perf record: Woken up 23 times to write data ]
  [ perf record: Captured and wrote 5.578 MB perf.data (6839 samples) ]
  $ perf report --header-only | egrep 'cpu(desc|.*capabilities)'
  # cpudesc : Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
  # cpu pmu capabilities: branches=32, max_precise=3, pmu_name=skylake
  $

Before:

  $ perf report --no-children --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 6K of event 'cycles:u'
  # Event count (approx.): 6459523879
  #
  # Overhead  Command      Shared Object     Symbol
  # ........  ...........  ................  .......................
  #
      99.95%  tchain_edit  tchain_edit       [.] f43
              |
               --99.92%--f43
                         f42
                         f41
                         f40
                         f39
                         f38
                         f37
                         f36
                         f35
                         f34
                         f33
                         f32
                         f31
                         f30
                         f29
                         f28
                         f27
                         f26
                         f25
                         f24
                         f23
                         f22
                         f21
                         f20
                         f19
                         f18
                         f17
                         f16
                         f15
                         f14
                         f13
                         f12
                         f11

       0.03%  tchain_edit  tchain_edit       [.] f42
       0.01%  tchain_edit  tchain_edit       [.] f41
       0.00%  tchain_edit  tchain_edit       [.] f31
       0.00%  tchain_edit  ld-2.29.so        [.] _dl_relocate_object
       0.00%  tchain_edit  ld-2.29.so        [.] memmove
       0.00%  tchain_edit  [unknown]         [k] 0xffffffff93a00b17

After:

  $ perf report --stitch-lbr --no-children --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 6K of event 'cycles:u'
  # Event count (approx.): 6459496645
  #
  # Overhead  Command      Shared Object     Symbol
  # ........  ...........  ................  ........................
  #
      99.97%  tchain_edit  tchain_edit       [.] f43
              |
               --99.93%--f43
                         f42
                         f41
                         f40
                         f39
                         f38
                         f37
                         f36
                         f35
                         f34
                         f33
                         f32
                         f31
                         f30
                         f29
                         f28
                         f27
                         f26
                         f25
                         f24
                         f23
                         f22
                         f21
                         f20
                         f19
                         f18
                         f17
                         f16
                         f15
                         f14
                         f13
                         f12
                         f11
                         f10
                         f9
                         f8
                         f7
                         f6
                         f5
                         f4
                         f3
                         f2
                         f1
                         main
                         __libc_start_main

       0.02%  tchain_edit  [unknown]         [k] 0xffffffff93a00b17
       0.01%  tchain_edit  tchain_edit       [.] f31
       0.00%  tchain_edit  ld-2.29.so        [.] _dl_important_hwcaps

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-14-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
ff165628d7 perf callchain: Stitch LBR call stack
In LBR call stack mode, the depth of reconstructed LBR call stack limits
to the number of LBR registers.

  For example, on skylake, the depth of reconstructed LBR call stack is
  always <= 32.

  # To display the perf.data header info, please use
  # --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 6K of event 'cycles'
  # Event count (approx.): 6487119731
  #
  # Children      Self  Command          Shared Object       Symbol
  # ........  ........  ...............  ..................
  # ................................

    99.97%    99.97%  tchain_edit      tchain_edit        [.] f43
            |
             --99.64%--f11
                       f12
                       f13
                       f14
                       f15
                       f16
                       f17
                       f18
                       f19
                       f20
                       f21
                       f22
                       f23
                       f24
                       f25
                       f26
                       f27
                       f28
                       f29
                       f30
                       f31
                       f32
                       f33
                       f34
                       f35
                       f36
                       f37
                       f38
                       f39
                       f40
                       f41
                       f42
                       f43

For a call stack which is deeper than LBR limit, HW will overwrite the
LBR register with oldest branch. Only partial call stacks can be
reconstructed.

However, the overwritten LBRs may still be retrieved from previous
sample. At that moment, HW hasn't overwritten the LBR registers yet.
Perf tools can stitch those overwritten LBRs on current call stacks to
get a more complete call stack.

To determine if LBRs can be stitched, perf tools need to compare current
sample with previous sample.

- They should have identical LBR records (Same from, to and flags
  values, and the same physical index of LBR registers).

- The searching starts from the base-of-stack of current sample.

Once perf determines to stitch the previous LBRs, the corresponding LBR
cursor nodes will be copied to 'lists'.  The 'lists' is to track the LBR
cursor nodes which are going to be stitched.

When the stitching is over, the nodes will not be freed immediately.
They will be moved to 'free_lists'. Next stitching may reuse the space.
Both 'lists' and 'free_lists' will be freed when all samples are
processed.

Committer notes:

Fix the intel-pt.c initialization of the union with 'struct
branch_flags', that breaks the build with its unnamed union on older gcc
versions.

Uninline thread__free_stitch_list(), as it grew big and started dragging
includes to thread.h, so move it to thread.c where what it needs in
terms of headers are already there.

This fixes the build in several systems such as debian:experimental when
cross building to the MIPS32 architecture, i.e. in the other cases what
was needed was being included by sheer luck.

  In file included from builtin-sched.c:11:
  util/thread.h: In function 'thread__free_stitch_list':
  util/thread.h:169:3: error: implicit declaration of function 'free' [-Werror=implicit-function-declaration]
    169 |   free(pos);
        |   ^~~~
  util/thread.h:169:3: error: incompatible implicit declaration of built-in function 'free' [-Werror]
  util/thread.h:19:1: note: include '<stdlib.h>' or provide a declaration of 'free'
     18 | #include "callchain.h"
    +++ |+#include <stdlib.h>
     19 |
  util/thread.h:174:3: error: incompatible implicit declaration of built-in function 'free' [-Werror]
    174 |   free(pos);
        |   ^~~~
  util/thread.h:174:3: note: include '<stdlib.h>' or provide a declaration of 'free'

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-13-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
7f1d39317c perf callchain: Save previous cursor nodes for LBR stitching approach
The cursor nodes which generates from sample are eventually added into
callchain. To avoid generating cursor nodes from previous samples again,
the previous cursor nodes are also saved for LBR stitching approach.

Some option, e.g. hide-unresolved, may hide some LBRs.  Add a variable
'valid' in struct callchain_cursor_node to indicate this case. The LBR
stitching approach will only append the valid cursor nodes from previous
samples later.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-12-kan.liang@linux.intel.com
[ Use zfree() instead of open coded equivalent, and use it when freeing members of structs ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
9c6c3f471d perf thread: Save previous sample for LBR stitching approach
To retrieve the overwritten LBRs from previous sample for LBR stitching
approach, perf has to save the previous sample.

Only allocate the struct lbr_stitch once, when LBR stitching approach is
enabled and kernel supports hw_idx.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-11-kan.liang@linux.intel.com
[ Use zalloc()/zfree() for thread->lbr_stitch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
771fd155df perf thread: Add a knob for LBR stitch approach
The LBR stitch approach should be disabled by default. Because

- The stitching approach base on LBR call stack technology. The known
  limitations of LBR call stack technology still apply to the approach,
  e.g. Exception handing such as setjmp/longjmp will have calls/returns
  not match.

- This approach is not foolproof. There can be cases where it creates
  incorrect call stacks from incorrect matches. There is no attempt to
  validate any matches in another way.

The 'lbr_stitch_enable' is used to indicate whether enable LBR stitch
approach, which is disabled by default. The following patch will
introduce a new option for each tools to enable the LBR stitch
approach.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-10-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
e2b23483eb perf machine: Factor out lbr_callchain_add_lbr_ip()
Both caller and callee needs to add ip from LBR to callchain.
Factor out lbr_callchain_add_lbr_ip() to improve code readability.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-9-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:01 -03:00
Kan Liang
dd3e249a0c perf machine: Factor out lbr_callchain_add_kernel_ip()
Both caller and callee needs to add kernel ip to callchain.  Factor out
lbr_callchain_add_kernel_ip() to improve code readability.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-8-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Kan Liang
e48b8311ca perf machine: Refine the function for LBR call stack reconstruction
LBR only collect the user call stack. To reconstruct a call stack, both
kernel call stack and user call stack are required. The function
resolve_lbr_callchain_sample() mix the kernel call stack and user call
stack.

Now, with the help of HW idx, perf tool can reconstruct a more complete
call stack by adding some user call stack from previous sample. However,
current implementation is hard to be extended to support it.

Current code path for resolve_lbr_callchain_sample()

  for (j = 0; j < mix_chain_nr; j++) {
       if (ORDER_CALLEE) {
             if (kernel callchain)
                  Fill callchain info
             else if (LBR callchain)
                  Fill callchain info
       } else {
             if (LBR callchain)
                  Fill callchain info
             else if (kernel callchain)
                  Fill callchain info
       }
       add_callchain_ip();
  }

With the patch,

  if (ORDER_CALLEE) {
       for (j = 0; j < NUM of kernel callchain) {
             Fill callchain info
             add_callchain_ip();
       }
       for (; j < mix_chain_nr) {
             Fill callchain info
             add_callchain_ip();
       }
  } else {
       for (; j < NUM of LBR callchain) {
             Fill callchain info
             add_callchain_ip();
       }
       for (j = 0; j < mix_chain_nr) {
             Fill callchain info
             add_callchain_ip();
       }
  }

No functional changes.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-7-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Kan Liang
f8603267bf perf machine: Remove the indent in resolve_lbr_callchain_sample
The indent is unnecessary in resolve_lbr_callchain_sample.  Removing it
will make the following patch simpler.

Current code path for resolve_lbr_callchain_sample()

        /* LBR only affects the user callchain */
        if (i != chain_nr) {
                body of the function
                ....
                return 1;
        }

        return 0;

With the patch,

        /* LBR only affects the user callchain */
        if (i == chain_nr)
                return 0;

        body of the function
        ...
        return 1;

No functional changes.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-6-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Kan Liang
6f91ea283a perf header: Support CPU PMU capabilities
To stitch LBR call stack, the max LBR information is required. So the
CPU PMU capabilities information has to be stored in perf header.

Add a new feature HEADER_CPU_PMU_CAPS for CPU PMU capabilities.
Retrieve all CPU PMU capabilities, not just max LBR information.

Add variable max_branches to facilitate future usage.

Committer testing:

  # ls -la /sys/devices/cpu/caps/
  total 0
  drwxr-xr-x. 2 root root    0 Apr 17 10:53 .
  drwxr-xr-x. 6 root root    0 Apr 17 07:02 ..
  -r--r--r--. 1 root root 4096 Apr 17 10:53 max_precise
  #
  # cat /sys/devices/cpu/caps/max_precise
  0
  # perf record sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.033 MB perf.data (7 samples) ]
  #
  # perf report --header-only | egrep 'cpu(desc|.*capabilities)'
  # cpudesc : AMD Ryzen 5 3600X 6-Core Processor
  # cpu pmu capabilities: max_precise=0
  #

And then on an Intel machine:

  $ ls -la /sys/devices/cpu/caps/
  total 0
  drwxr-xr-x. 2 root root    0 Apr 17 10:51 .
  drwxr-xr-x. 6 root root    0 Apr 17 10:04 ..
  -r--r--r--. 1 root root 4096 Apr 17 11:37 branches
  -r--r--r--. 1 root root 4096 Apr 17 10:51 max_precise
  -r--r--r--. 1 root root 4096 Apr 17 11:37 pmu_name
  $ cat /sys/devices/cpu/caps/max_precise
  3
  $ cat /sys/devices/cpu/caps/branches
  32
  $ cat /sys/devices/cpu/caps/pmu_name
  skylake
  $ perf record sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
  $ perf report --header-only | egrep 'cpu(desc|.*capabilities)'
  # cpudesc : Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz
  # cpu pmu capabilities: branches=32, max_precise=3, pmu_name=skylake
  $

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-3-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Jiri Olsa
3a6c51e4d6 perf parser: Add support to specify rXXX event with pmu
The current rXXXX event specification creates event under PERF_TYPE_RAW
pmu type. This change allows to use rXXXX within pmu syntax, so it's
type is used via the following syntax:

  -e 'cpu/r3c/'
  -e 'cpum_cf/r0/'

The XXXX number goes directly to perf_event_attr::config the same way as
in '-e rXXXX' event. The perf_event_attr::type is filled with pmu type.

Committer testing:

So, lets see what goes in perf_event_attr::config for, say, the
'instructions' PERF_TYPE_HARDWARE (0) event, first we should look at how
to encode this event as a PERF_TYPE_RAW event for this specific CPU, an
AMD Ryzen 5:

  # cat /sys/devices/cpu/events/instructions
  event=0xc0
  #

Then try with it _and_ the instruction, just to see that they are close
enough:

  # perf stat -e rc0,instructions sleep 1

   Performance counter stats for 'sleep 1':

             919,794      rc0
             919,898      instructions

         1.000754579 seconds time elapsed

         0.000715000 seconds user
         0.000000000 seconds sys
  #

Now we should try, before this patch, the PMU event encoding:

  # perf stat -e cpu/rc0/ sleep 1
  event syntax error: 'cpu/rc0/'
                           \___ unknown term

  valid terms: event,edge,inv,umask,cmask,config,config1,config2,name,period,percore
  #

Now with this patch, the three ways of specifying the 'instructions' CPU
counter are accepted:

  # perf stat -e cpu/rc0/,rc0,instructions sleep 1

   Performance counter stats for 'sleep 1':

             892,948      cpu/rc0/
             893,052      rc0
             893,156      instructions

         1.000931819 seconds time elapsed

         0.000916000 seconds user
         0.000000000 seconds sys

  #

Requested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200416221405.437788-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Ian Rogers
e9cfa47e68 perf doc: allow ASCIIDOC_EXTRA to be an argument
This will allow parent makefiles to pass values to asciidoc.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jiwei Sun <jiwei.sun@windriver.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: yuzhoujian <yuzhoujian@didichuxing.com>
Link: http://lore.kernel.org/lkml/20200416162058.201954-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Kan Liang
9fbc61f832 perf pmu: Add support for PMU capabilities
The PMU capabilities information, which is located at
/sys/bus/event_source/devices/<dev>/caps, is required by perf tool.  For
example, the max LBR information is required to stitch LBR call stack.

Add perf_pmu__caps_parse() to parse the PMU capabilities information.
The information is stored in a list.

The following patch will store the capabilities information in perf
header.

Committer notes:

Here's an example of such directories and its files in an i5 7th gen
machine:

  [root@seventh ~]# ls -lad /sys/bus/event_source/devices/*/caps
  drwxr-xr-x. 2 root root 0 Apr 14 13:33 /sys/bus/event_source/devices/cpu/caps
  drwxr-xr-x. 2 root root 0 Apr 14 13:33 /sys/bus/event_source/devices/intel_pt/caps
  [root@seventh ~]# ls -la /sys/bus/event_source/devices/intel_pt/caps
  total 0
  drwxr-xr-x. 2 root root    0 Apr 14 13:33 .
  drwxr-xr-x. 5 root root    0 Apr 14 13:12 ..
  -r--r--r--. 1 root root 4096 Apr 16 13:10 cr3_filtering
  -r--r--r--. 1 root root 4096 Apr 16 11:42 cycle_thresholds
  -r--r--r--. 1 root root 4096 Apr 16 13:10 ip_filtering
  -r--r--r--. 1 root root 4096 Apr 16 13:10 max_subleaf
  -r--r--r--. 1 root root 4096 Apr 14 13:33 mtc
  -r--r--r--. 1 root root 4096 Apr 14 13:33 mtc_periods
  -r--r--r--. 1 root root 4096 Apr 16 13:10 num_address_ranges
  -r--r--r--. 1 root root 4096 Apr 16 13:10 output_subsys
  -r--r--r--. 1 root root 4096 Apr 16 13:10 payloads_lip
  -r--r--r--. 1 root root 4096 Apr 16 13:10 power_event_trace
  -r--r--r--. 1 root root 4096 Apr 14 13:33 psb_cyc
  -r--r--r--. 1 root root 4096 Apr 14 13:33 psb_periods
  -r--r--r--. 1 root root 4096 Apr 16 13:10 ptwrite
  -r--r--r--. 1 root root 4096 Apr 16 13:10 single_range_output
  -r--r--r--. 1 root root 4096 Apr 16 12:03 topa_multiple_entries
  -r--r--r--. 1 root root 4096 Apr 16 13:10 topa_output
  [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/topa_output
  1
  [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/topa_multiple_entries
  1
  [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/mtc
  1
  [root@seventh ~]# cat /sys/bus/event_source/devices/intel_pt/caps/power_event_trace
  0
  [root@seventh ~]#

  [root@seventh ~]# ls -la /sys/bus/event_source/devices/cpu/caps/
  total 0
  drwxr-xr-x. 2 root root    0 Apr 14 13:33 .
  drwxr-xr-x. 6 root root    0 Apr 14 13:12 ..
  -r--r--r--. 1 root root 4096 Apr 16 13:10 branches
  -r--r--r--. 1 root root 4096 Apr 14 13:33 max_precise
  -r--r--r--. 1 root root 4096 Apr 16 13:10 pmu_name
  [root@seventh ~]# cat /sys/bus/event_source/devices/cpu/caps/max_precise
  3
  [root@seventh ~]# cat /sys/bus/event_source/devices/cpu/caps/branches
  32
  [root@seventh ~]# cat /sys/bus/event_source/devices/cpu/caps/pmu_name
  skylake
  [root@seventh ~]#

Wow, first time I've heard about
/sys/bus/event_source/devices/cpu/caps/max_precise, I think I'll use it!
:-)

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
He Zhe
f8ff18be1f tools lib traceevent: Take care of return value of asprintf
According to the API, if memory allocation wasn't possible, or some
other error occurs, asprintf will return -1, and the contents of strp
below are undefined.

  int asprintf(char **strp, const char *fmt, ...);

This patch takes care of return value of asprintf to make it less error
prone and prevent the following build warning.

  ignoring return value of ‘asprintf’, declared with attribute warn_unused_result [-Wunused-result]

Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Cc: hewenliang4@huawei.com
Link: http://lore.kernel.org/lkml/1582163930-233692-1-git-send-email-zhe.he@windriver.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Stephane Eranian
bec49a9e05 perf stat: Force error in fallback on :k events
When it is not possible for a non-privilege perf command to monitor at
the kernel level (:k), the fallback code forces a :u. That works if the
event was previously monitoring both levels.  But if the event was
already constrained to kernel only, then it does not make sense to
restrict it to user only.

Given the code works by exclusion, a kernel only event would have:

  attr->exclude_user = 1

The fallback code would add:

  attr->exclude_kernel = 1

In the end the end would not monitor in either the user level or kernel
level. In other words, it would count nothing.

An event programmed to monitor kernel only cannot be switched to user
only without seriously warning the user.

This patch forces an error in this case to make it clear the request
cannot really be satisfied.

Behavior with paranoid 1:

  $ sudo bash -c "echo 1 > /proc/sys/kernel/perf_event_paranoid"
  $ perf stat -e cycles:k sleep 1

   Performance counter stats for 'sleep 1':

           1,520,413      cycles:k

         1.002361664 seconds time elapsed

         0.002480000 seconds user
         0.000000000 seconds sys

Old behavior with paranoid 2:

  $ sudo bash -c "echo 2 > /proc/sys/kernel/perf_event_paranoid"
  $ perf stat -e cycles:k sleep 1
   Performance counter stats for 'sleep 1':

                   0      cycles:ku

         1.002358127 seconds time elapsed

         0.002384000 seconds user
         0.000000000 seconds sys

New behavior with paranoid 2:

  $ sudo bash -c "echo 2 > /proc/sys/kernel/perf_event_paranoid"
  $ perf stat -e cycles:k sleep 1
  Error:
  You may not have permission to collect stats.

  Consider tweaking /proc/sys/kernel/perf_event_paranoid,
  which controls use of the performance events system by
  unprivileged users (without CAP_PERFMON or CAP_SYS_ADMIN).

  The current value is 2:

    -1: Allow use of (almost) all events by all users
        Ignore mlock limit after perf_event_mlock_kb without CAP_IPC_LOCK
  >= 0: Disallow ftrace function tracepoint by users without CAP_PERFMON or CAP_SYS_ADMIN
        Disallow raw tracepoint access by users without CAP_SYS_PERFMON or CAP_SYS_ADMIN
  >= 1: Disallow CPU event access by users without CAP_PERFMON or CAP_SYS_ADMIN
  >= 2: Disallow kernel profiling by users without CAP_PERFMON or CAP_SYS_ADMIN

  To make this setting permanent, edit /etc/sysctl.conf too, e.g.:

          kernel.perf_event_paranoid = -1

v2 of this patch addresses the review feedback from jolsa@redhat.com.

Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200414161550.225588-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Adrian Hunter
e345997914 perf tools: Add support for leader-sampling with AUX area events
When AUX area events are used in sampling mode, they must be the group
leader, but the group leader is also used for leader-sampling. However,
it is not desirable to use an AUX area event as the leader for
leader-sampling, because it doesn't have any samples of its own. To support
leader-sampling with AUX area events, use the 2nd event of the group as the
"leader" for the purposes of leader-sampling.

Example:

 # perf record --kcore --aux-sample -e '{intel_pt//,cycles,instructions}:S' -c 10000 uname
 [ perf record: Woken up 3 times to write data ]
 [ perf record: Captured and wrote 0.786 MB perf.data ]
 # perf report
 Samples: 380  of events 'anon group { cycles, instructions }', Event count (approx.): 3026164
           Children              Self  Command  Shared Object      Symbol
 +   38.76%  42.65%     0.00%   0.00%  uname    [kernel.kallsyms]  [k] __x86_indirect_thunk_rax
 +   35.82%  31.33%     0.00%   0.00%  uname    ld-2.28.so         [.] _dl_start_user
 +   34.29%  29.74%     0.55%   0.47%  uname    ld-2.28.so         [.] _dl_start
 +   33.73%  28.62%     1.60%   0.97%  uname    ld-2.28.so         [.] dl_main
 +   33.19%  29.04%     0.52%   0.32%  uname    ld-2.28.so         [.] _dl_sysdep_start
 +   27.83%  33.74%     0.00%   0.00%  uname    [kernel.kallsyms]  [k] do_syscall_64
 +   26.76%  33.29%     0.00%   0.00%  uname    [kernel.kallsyms]  [k] entry_SYSCALL_64_after_hwframe
 +   23.78%  20.33%     5.97%   5.25%  uname    [kernel.kallsyms]  [k] page_fault
 +   23.18%  24.60%     0.00%   0.00%  uname    libc-2.28.so       [.] __libc_start_main
 +   22.64%  24.37%     0.00%   0.00%  uname    uname              [.] _start
 +   21.04%  23.27%     0.00%   0.00%  uname    uname              [.] main
 +   19.48%  18.08%     3.72%   3.64%  uname    ld-2.28.so         [.] _dl_relocate_object
 +   19.47%  21.81%     0.00%   0.00%  uname    libc-2.28.so       [.] setlocale
 +   19.44%  21.56%     0.52%   0.61%  uname    libc-2.28.so       [.] _nl_find_locale
 +   17.87%  19.66%     0.00%   0.00%  uname    libc-2.28.so       [.] _nl_load_locale_from_archive
 +   15.71%  13.73%     0.53%   0.52%  uname    [kernel.kallsyms]  [k] do_page_fault
 +   15.18%  13.21%     1.03%   0.68%  uname    [kernel.kallsyms]  [k] handle_mm_fault
 +   14.15%  12.53%     1.01%   1.12%  uname    [kernel.kallsyms]  [k] __handle_mm_fault
 +   12.03%   9.67%     0.54%   0.32%  uname    ld-2.28.so         [.] _dl_map_object
 +   10.55%   8.48%     0.00%   0.00%  uname    ld-2.28.so         [.] openaux
 +   10.55%  20.20%     0.52%   0.61%  uname    libc-2.28.so       [.] __run_exit_handlers

Comnmitter notes:

Fixed up this problem:

  util/record.c: In function ‘perf_evlist__config’:
  util/record.c:256:3: error: too few arguments to function ‘perf_evsel__config_leader_sampling’
    256 |   perf_evsel__config_leader_sampling(evsel);
        |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/record.c:190:13: note: declared here
    190 | static void perf_evsel__config_leader_sampling(struct evsel *evsel,
        |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-17-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Adrian Hunter
94d3820f2e perf evlist: Allow multiple read formats
Tools find the correct evsel, and therefore read format, using the event
ID, so it isn't necessary for all read formats to be the same. In the
case of leader-sampling of AUX area events, dummy tracking events will
have a different read format, so relax the validation to become a debug
message only.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-16-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Adrian Hunter
3713eb371c perf evsel: Rearrange perf_evsel__config_leader_sampling()
In preparation for adding support for leader sampling with AUX area events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-15-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Adrian Hunter
5f34278867 perf evlist: Move leader-sampling configuration
Move leader-sampling configuration in preparation for adding support for
leader sampling with AUX area events.

Committer notes:

It only makes sense when configuring an evsel that is part of an evlist,
so the only case where it is called outside perf_evlist__config(), in
some 'perf test' entry, is safe, and even there we should just use
perf_evlist__config(), but since in that case we have just one evsel in
the evlist, it is equivalent.

Also fixed up this problem:

  util/record.c: In function ‘perf_evlist__config’:
  util/record.c:223:3: error: too many arguments to function ‘perf_evsel__config_leader_sampling’
    223 |   perf_evsel__config_leader_sampling(evsel, evlist);
        |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/record.c:170:13: note: declared here
    170 | static void perf_evsel__config_leader_sampling(struct evsel *evsel)
        |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-14-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:05:00 -03:00
Adrian Hunter
e12ee9f751 perf evsel: Move and globalize perf_evsel__find_pmu() and perf_evsel__is_aux_event()
Move and globalize 2 functions from the auxtrace specific sources so
that they can be reused.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-13-adrian.hunter@intel.com
[ Move to pmu.c, as moving to evsel.h breaks the python binding ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-18 09:04:32 -03:00
Adrian Hunter
2855c05cf1 perf intel-pt: Add support for synthesizing callchains for regular events
Currently, callchains can be synthesized only for synthesized events.
Support also synthesizing callchains for regular events.

Example:

 # perf record --kcore --aux-sample -e '{intel_pt//,cycles}' -c 10000 uname
 Linux
 [ perf record: Woken up 3 times to write data ]
 [ perf record: Captured and wrote 0.532 MB perf.data ]
 # perf script --itrace=Ge | head -20
 uname  4864 2419025.358181:      10000     cycles:
        ffffffffbba56965 apparmor_bprm_committing_creds+0x35 ([kernel.kallsyms])
        ffffffffbc400cd5 __indirect_thunk_start+0x5 ([kernel.kallsyms])
        ffffffffbba07422 security_bprm_committing_creds+0x22 ([kernel.kallsyms])
        ffffffffbb89805d install_exec_creds+0xd ([kernel.kallsyms])
        ffffffffbb90d9ac load_elf_binary+0x3ac ([kernel.kallsyms])

 uname  4864 2419025.358185:      10000     cycles:
        ffffffffbba56db0 apparmor_bprm_committed_creds+0x20 ([kernel.kallsyms])
        ffffffffbc400cd5 __indirect_thunk_start+0x5 ([kernel.kallsyms])
        ffffffffbba07452 security_bprm_committed_creds+0x22 ([kernel.kallsyms])
        ffffffffbb89809a install_exec_creds+0x4a ([kernel.kallsyms])
        ffffffffbb90d9ac load_elf_binary+0x3ac ([kernel.kallsyms])

 uname  4864 2419025.358189:      10000     cycles:
        ffffffffbb86fdf6 vma_adjust_trans_huge+0x6 ([kernel.kallsyms])
        ffffffffbb821660 __vma_adjust+0x160 ([kernel.kallsyms])
        ffffffffbb897be7 shift_arg_pages+0x97 ([kernel.kallsyms])
        ffffffffbb897ed9 setup_arg_pages+0x1e9 ([kernel.kallsyms])
        ffffffffbb90d9f2 load_elf_binary+0x3f2 ([kernel.kallsyms])

Committer testing:

  # perf record --kcore --aux-sample -e '{intel_pt//,cycles}' -c 10000 uname
  Linux
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.233 MB perf.data ]
  #

Then, before this patch:

  # perf script --itrace=Ge | head -20
     uname 28642 168664.856384: 10000 cycles: ffffffff9810aeaa commit_creds+0x2a ([kernel.kallsyms])
     uname 28642 168664.856388: 10000 cycles: ffffffff982a24f1 mprotect_fixup+0x151 ([kernel.kallsyms])
     uname 28642 168664.856392: 10000 cycles: ffffffff982a385b move_page_tables+0xbcb ([kernel.kallsyms])
     uname 28642 168664.856396: 10000 cycles: ffffffff982fd4ec __mod_memcg_state+0x1c ([kernel.kallsyms])
     uname 28642 168664.856400: 10000 cycles: ffffffff9829fddd do_mmap+0xfd ([kernel.kallsyms])
     uname 28642 168664.856404: 10000 cycles: ffffffff9829c879 __vma_adjust+0x479 ([kernel.kallsyms])
     uname 28642 168664.856408: 10000 cycles: ffffffff98238e94 __perf_addr_filters_adjust+0x34 ([kernel.kallsyms])
     uname 28642 168664.856412: 10000 cycles: ffffffff98a38e0b down_write+0x1b ([kernel.kallsyms])
     uname 28642 168664.856416: 10000 cycles: ffffffff983006a0 memcg_kmem_get_cache+0x0 ([kernel.kallsyms])
     uname 28642 168664.856421: 10000 cycles: ffffffff98396eaf load_elf_binary+0x92f ([kernel.kallsyms])
     uname 28642 168664.856425: 10000 cycles: ffffffff982e0222 kfree+0x62 ([kernel.kallsyms])
     uname 28642 168664.856428: 10000 cycles: ffffffff9846dfd4 file_has_perm+0x54 ([kernel.kallsyms])
     uname 28642 168664.856433: 10000 cycles: ffffffff98288911 vma_interval_tree_insert+0x51 ([kernel.kallsyms])
     uname 28642 168664.856437: 10000 cycles: ffffffff9823e577 perf_event_mmap_output+0x27 ([kernel.kallsyms])
     uname 28642 168664.856441: 10000 cycles: ffffffff98a26fa0 xas_load+0x40 ([kernel.kallsyms])
     uname 28642 168664.856445: 10000 cycles: ffffffff98004f30 arch_setup_additional_pages+0x0 ([kernel.kallsyms])
     uname 28642 168664.856448: 10000 cycles: ffffffff98a297c0 copy_user_generic_unrolled+0xa0 ([kernel.kallsyms])
     uname 28642 168664.856452: 10000 cycles: ffffffff9853a87a strnlen_user+0x10a ([kernel.kallsyms])
     uname 28642 168664.856456: 10000 cycles: ffffffff986638a7 randomize_page+0x27 ([kernel.kallsyms])
     uname 28642 168664.856460: 10000 cycles: ffffffff98a3b645 _raw_spin_lock+0x5 ([kernel.kallsyms])

  #

And after:

  # perf script --itrace=Ge | head -20
  uname 28642 168664.856384:      10000     cycles:
  	ffffffff9810aeaa commit_creds+0x2a ([kernel.kallsyms])
  	ffffffff9831fe87 install_exec_creds+0x17 ([kernel.kallsyms])
  	ffffffff983968d9 load_elf_binary+0x359 ([kernel.kallsyms])
  	ffffffff98e00c45 __x86_indirect_thunk_rax+0x5 ([kernel.kallsyms])
  	ffffffff98e00c45 __x86_indirect_thunk_rax+0x5 ([kernel.kallsyms])

  uname 28642 168664.856388:      10000     cycles:
  	ffffffff982a24f1 mprotect_fixup+0x151 ([kernel.kallsyms])
  	ffffffff9831fa83 setup_arg_pages+0x123 ([kernel.kallsyms])
  	ffffffff9839691f load_elf_binary+0x39f ([kernel.kallsyms])
  	ffffffff98e00c45 __x86_indirect_thunk_rax+0x5 ([kernel.kallsyms])
  	ffffffff98e00c45 __x86_indirect_thunk_rax+0x5 ([kernel.kallsyms])

  uname 28642 168664.856392:      10000     cycles:
  	ffffffff982a385b move_page_tables+0xbcb ([kernel.kallsyms])
  	ffffffff9831f889 shift_arg_pages+0xa9 ([kernel.kallsyms])
  	ffffffff9831fb4f setup_arg_pages+0x1ef ([kernel.kallsyms])
  	ffffffff9839691f load_elf_binary+0x39f ([kernel.kallsyms])
  	ffffffff98e00c45 __x86_indirect_thunk_rax+0x5 ([kernel.kallsyms])
  #

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-12-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:17 -03:00
Adrian Hunter
e11869a065 perf evsel: Add support for synthesized sample type
For reporting purposes, an evsel sample can have a callchain synthesized
from AUX area data. Add support for keeping track of synthesized sample
types. Note, the recorded sample_type cannot be changed because it is
needed to continue to parse events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-11-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:17 -03:00
Adrian Hunter
8e94b3243a perf evsel: Be consistent when looking which evsel PERF_SAMPLE_ bits are set
Using 'type' variable for checking for callchains is equivalent to using
evsel__has_callchain(evsel) and is how the other PERF_SAMPLE_ bits are checked
in this function, so use it to be consistent.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-11-adrian.hunter@intel.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:17 -03:00
Adrian Hunter
4fef41bfb1 perf thread-stack: Add thread_stack__sample_late()
Add a thread stack function to create a call chain for hardware events
where the sample records get created some time after the event occurred.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-10-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
1c5c25b3fd perf auxtrace: Add an option to synthesize callchains for regular events
Currently, callchains can be synthesized only for synthesized events. Add
an itrace option to synthesize callchains for regular events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-9-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
5c7bec0c9c perf auxtrace: For reporting purposes, un-group AUX area event
An AUX area event must be the group leader when recording traces in
sample mode, but that does not produce the expected results from
'perf report' because it expects the leader to provide samples.

Rather than teach 'perf report' about AUX area sampling, un-group the
AUX area event during processing, making the 2nd event the leader.

Example:

 $ perf record -e '{intel_pt//u,branch-misses:u}' -c 1 uname
 Linux
 [ perf record: Woken up 1 times to write data ]
 [ perf record: Captured and wrote 0.080 MB perf.data ]

 Before:

 $ perf report

 Samples: 800  of events 'anon group { intel_pt//u, branch-misses:u }', Event count (approx.): 800
        Children              Self  Command  Shared Object     Symbol
     0.00%  47.50%     0.00%  47.50%  uname    libc-2.28.so      [.] _dl_addr
     0.00%  16.38%     0.00%  16.38%  uname    ld-2.28.so        [.] __GI___tunables_init
     0.00%  54.75%     0.00%   4.75%  uname    ld-2.28.so        [.] dl_main
     0.00%   3.12%     0.00%   3.12%  uname    ld-2.28.so        [.] _dl_map_object_from_fd
     0.00%   2.38%     0.00%   2.38%  uname    ld-2.28.so        [.] strcmp
     0.00%   2.25%     0.00%   2.25%  uname    ld-2.28.so        [.] _dl_check_map_versions
     0.00%   2.00%     0.00%   2.00%  uname    ld-2.28.so        [.] _dl_important_hwcaps
     0.00%   2.00%     0.00%   2.00%  uname    ld-2.28.so        [.] _dl_map_object_deps
     0.00%  51.50%     0.00%   1.50%  uname    ld-2.28.so        [.] _dl_sysdep_start
     0.00%   1.25%     0.00%   1.25%  uname    ld-2.28.so        [.] _dl_load_cache_lookup
     0.00%  51.12%     0.00%   1.12%  uname    ld-2.28.so        [.] _dl_start
     0.00%  50.88%     0.00%   1.12%  uname    ld-2.28.so        [.] do_lookup_x
     0.00%  50.62%     0.00%   1.00%  uname    ld-2.28.so        [.] _dl_lookup_symbol_x
     0.00%   1.00%     0.00%   1.00%  uname    ld-2.28.so        [.] _dl_map_object
     0.00%   1.00%     0.00%   1.00%  uname    ld-2.28.so        [.] _dl_next_ld_env_entry
     0.00%   0.88%     0.00%   0.88%  uname    ld-2.28.so        [.] _dl_cache_libcmp
     0.00%   0.88%     0.00%   0.88%  uname    ld-2.28.so        [.] _dl_new_object
     0.00%  50.88%     0.00%   0.88%  uname    ld-2.28.so        [.] _dl_relocate_object
     0.00%   0.62%     0.00%   0.62%  uname    ld-2.28.so        [.] _dl_init_paths
     0.00%   0.62%     0.00%   0.62%  uname    ld-2.28.so        [.] _dl_name_match_p
     0.00%   0.50%     0.00%   0.50%  uname    ld-2.28.so        [.] get_common_indeces.constprop.1
     0.00%   0.50%     0.00%   0.50%  uname    ld-2.28.so        [.] memmove
     0.00%   0.50%     0.00%   0.50%  uname    ld-2.28.so        [.] memset
     0.00%   0.50%     0.00%   0.50%  uname    ld-2.28.so        [.] open_verify.constprop.11
     0.00%   0.38%     0.00%   0.38%  uname    ld-2.28.so        [.] _dl_check_all_versions
     0.00%   0.38%     0.00%   0.38%  uname    ld-2.28.so        [.] _dl_find_dso_for_object
     0.00%   0.38%     0.00%   0.38%  uname    ld-2.28.so        [.] init_tls
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] __tunable_get_val
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] _dl_add_to_namespace_list
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] _dl_determine_tlsoffset
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] _dl_discover_osversion
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] calloc@plt
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] malloc
     0.00%   0.25%     0.00%   0.25%  uname    ld-2.28.so        [.] malloc@plt
     0.00%   0.25%     0.00%   0.25%  uname    libc-2.28.so      [.] _nl_load_locale_from_archive
     0.00%   0.25%     0.00%   0.25%  uname    [unknown]         [k] 0xffffffffa3a00010
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] __libc_scratch_buffer_set_array_size
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] _dl_allocate_tls_storage
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] _dl_catch_exception
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] _dl_setup_hash
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] _dl_sort_maps
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] _dl_sysdep_read_whole_file
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] access
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] calloc
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] mmap64
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] openaux
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] rtld_lock_default_lock_recursive
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] rtld_lock_default_unlock_recursive
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] strchr
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] strlen
     0.00%   0.12%     0.00%   0.12%  uname    ld-2.28.so        [.] 0x0000000000001080
     0.00%   0.12%     0.00%   0.12%  uname    libc-2.28.so      [.] __strchrnul_avx2
     0.00%   0.12%     0.00%   0.12%  uname    libc-2.28.so      [.] _nl_normalize_codeset
     0.00%   0.12%     0.00%   0.12%  uname    libc-2.28.so      [.] malloc
     0.00%   0.12%     0.00%   0.12%  uname    [unknown]         [k] 0xffffffffa3a011f0
     0.00%  50.00%     0.00%   0.00%  uname    ld-2.28.so        [.] _dl_start_user
     0.00%  50.00%     0.00%   0.00%  uname    [unknown]         [.] 0000000000000000

 After:

 Samples: 800  of event 'branch-misses:u', Event count (approx.): 800
  Children      Self  Command  Shared Object     Symbol
    54.75%     4.75%  uname    ld-2.28.so        [.] dl_main
    51.50%     1.50%  uname    ld-2.28.so        [.] _dl_sysdep_start
    51.12%     1.12%  uname    ld-2.28.so        [.] _dl_start
    50.88%     0.88%  uname    ld-2.28.so        [.] _dl_relocate_object
    50.88%     1.12%  uname    ld-2.28.so        [.] do_lookup_x
    50.62%     1.00%  uname    ld-2.28.so        [.] _dl_lookup_symbol_x
    50.00%     0.00%  uname    ld-2.28.so        [.] _dl_start_user
    50.00%     0.00%  uname    [unknown]         [.] 0000000000000000
    47.50%    47.50%  uname    libc-2.28.so      [.] _dl_addr
    16.38%    16.38%  uname    ld-2.28.so        [.] __GI___tunables_init
     3.12%     3.12%  uname    ld-2.28.so        [.] _dl_map_object_from_fd
     2.38%     2.38%  uname    ld-2.28.so        [.] strcmp
     2.25%     2.25%  uname    ld-2.28.so        [.] _dl_check_map_versions
     2.00%     2.00%  uname    ld-2.28.so        [.] _dl_important_hwcaps
     2.00%     2.00%  uname    ld-2.28.so        [.] _dl_map_object_deps
     1.25%     1.25%  uname    ld-2.28.so        [.] _dl_load_cache_lookup
     1.00%     1.00%  uname    ld-2.28.so        [.] _dl_map_object
     1.00%     1.00%  uname    ld-2.28.so        [.] _dl_next_ld_env_entry
     0.88%     0.88%  uname    ld-2.28.so        [.] _dl_cache_libcmp
     0.88%     0.88%  uname    ld-2.28.so        [.] _dl_new_object
     0.62%     0.62%  uname    ld-2.28.so        [.] _dl_init_paths
     0.62%     0.62%  uname    ld-2.28.so        [.] _dl_name_match_p
     0.50%     0.50%  uname    ld-2.28.so        [.] get_common_indeces.constprop.1
     0.50%     0.50%  uname    ld-2.28.so        [.] memmove
     0.50%     0.50%  uname    ld-2.28.so        [.] memset
     0.50%     0.50%  uname    ld-2.28.so        [.] open_verify.constprop.11
     0.38%     0.38%  uname    ld-2.28.so        [.] _dl_check_all_versions
     0.38%     0.38%  uname    ld-2.28.so        [.] _dl_find_dso_for_object
     0.38%     0.38%  uname    ld-2.28.so        [.] init_tls
     0.25%     0.25%  uname    ld-2.28.so        [.] __tunable_get_val
     0.25%     0.25%  uname    ld-2.28.so        [.] _dl_add_to_namespace_list
     0.25%     0.25%  uname    ld-2.28.so        [.] _dl_determine_tlsoffset
     0.25%     0.25%  uname    ld-2.28.so        [.] _dl_discover_osversion
     0.25%     0.25%  uname    ld-2.28.so        [.] calloc@plt
     0.25%     0.25%  uname    ld-2.28.so        [.] malloc
     0.25%     0.25%  uname    ld-2.28.so        [.] malloc@plt
     0.25%     0.25%  uname    libc-2.28.so      [.] _nl_load_locale_from_archive
     0.25%     0.25%  uname    [unknown]         [k] 0xffffffffa3a00010
     0.12%     0.12%  uname    ld-2.28.so        [.] __libc_scratch_buffer_set_array_size
     0.12%     0.12%  uname    ld-2.28.so        [.] _dl_allocate_tls_storage
     0.12%     0.12%  uname    ld-2.28.so        [.] _dl_catch_exception
     0.12%     0.12%  uname    ld-2.28.so        [.] _dl_setup_hash
     0.12%     0.12%  uname    ld-2.28.so        [.] _dl_sort_maps
     0.12%     0.12%  uname    ld-2.28.so        [.] _dl_sysdep_read_whole_file
     0.12%     0.12%  uname    ld-2.28.so        [.] access
     0.12%     0.12%  uname    ld-2.28.so        [.] calloc
     0.12%     0.12%  uname    ld-2.28.so        [.] mmap64
     0.12%     0.12%  uname    ld-2.28.so        [.] openaux
     0.12%     0.12%  uname    ld-2.28.so        [.] rtld_lock_default_lock_recursive
     0.12%     0.12%  uname    ld-2.28.so        [.] rtld_lock_default_unlock_recursive
     0.12%     0.12%  uname    ld-2.28.so        [.] strchr
     0.12%     0.12%  uname    ld-2.28.so        [.] strlen
     0.12%     0.12%  uname    ld-2.28.so        [.] 0x0000000000001080
     0.12%     0.12%  uname    libc-2.28.so      [.] __strchrnul_avx2
     0.12%     0.12%  uname    libc-2.28.so      [.] _nl_normalize_codeset
     0.12%     0.12%  uname    libc-2.28.so      [.] malloc
     0.12%     0.12%  uname    [unknown]         [k] 0xffffffffa3a011f0

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
113fcb46cf perf s390-cpumsf: Implement ->evsel_is_auxtrace() callback
Implement ->evsel_is_auxtrace() callback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-7-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
a58ab57caa perf cs-etm: Implement ->evsel_is_auxtrace() callback
Implement ->evsel_is_auxtrace() callback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
508c71e3f9 perf arm-spe: Implement ->evsel_is_auxtrace() callback
Implement ->evsel_is_auxtrace() callback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
966246f597 perf intel-bts: Implement ->evsel_is_auxtrace() callback
Implement ->evsel_is_auxtrace() callback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
6b52bb07c3 perf intel-pt: Implement ->evsel_is_auxtrace() callback
Implement ->evsel_is_auxtrace() callback.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Adrian Hunter
853f37d75c perf auxtrace: Add ->evsel_is_auxtrace() callback
Add ->evsel_is_auxtrace() callback to identify if a selected event
is an AUX area event.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:15 -03:00
Andreas Gerstmayr
5287f92692 perf script: Add flamegraph.py script
This script works in tandem with d3-flame-graph to generate flame graphs
from perf. It supports two output formats: JSON and HTML (the default).
The HTML format will look for a standalone d3-flame-graph template file
in /usr/share/d3-flame-graph/d3-flamegraph-base.html and fill in the
collected stacks.

Usage:

    perf record -a -g -F 99 sleep 60
    perf script report flamegraph

Combined:

    perf script flamegraph -a -F 99 sleep 60

Committer testing:

Tested both with "PYTHON=python3" and with the default, that uses
python2-devel:

Complete set of instructions:

  $ mkdir /tmp/build/perf
  $ make PYTHON=python3 -C tools/perf O=/tmp/build/perf install-bin
  $ export PATH=~/bin:$PATH
  $ perf record -a -g -F 99 sleep 60
  $ perf script report flamegraph

Now go and open the generated flamegraph.html file in a browser.

At first this required building with PYTHON=python3, but after I
reported this Andreas was kind enough to send a patch making it work
with both python and python3.

Signed-off-by: Andreas Gerstmayr <agerstmayr@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brendan Gregg <bgregg@netflix.com>
Cc: Martin Spier <mspier@netflix.com>
Link: http://lore.kernel.org/lkml/20200320151355.66302-1-agerstmayr@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:14 -03:00
Kajol Jain
47352aba40 perf metrictroup: Split the metricgroup__add_metric function
This patch refactors metricgroup__add_metric function where some part of
it move to function metricgroup__add_metric_param.  No logic change.

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-4-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:13 -03:00
Jiri Olsa
871f9f599d perf expr: Add expr_scanner_ctx object
Add the expr_scanner_ctx object to hold user data for the expr scanner.
Currently it holds only start_token, Kajol Jain will use it to hold 24x7
runtime param.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-3-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:13 -03:00
Jiri Olsa
aecce63e2b perf expr: Add expr_ prefix for parse_ctx and parse_id
Adding expr_ prefix for parse_ctx and parse_id, to straighten out the
expr* namespace.

There's no functional change.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-2-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:13 -03:00
Ian Rogers
04ed4ccb9c perf synthetic-events: save 4kb from 2 stack frames
Reuse an existing char buffer to avoid two PATH_MAX sized char buffers.

Reduces stack frame sizes by 4kb.

perf_event__synthesize_mmap_events before 'sub $0x45b8,%rsp' after
'sub $0x35b8,%rsp'.

perf_event__get_comm_ids before 'sub $0x2028,%rsp' after
'sub $0x1028,%rsp'.

The performance impact of this change is negligible.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200402154357.107873-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:13 -03:00
Stephane Eranian
c6fddb28ba tools api fs: Make xxx__mountpoint() more scalable
The xxx_mountpoint() interface provided by fs.c finds mount points for
common pseudo filesystems. The first time xxx_mountpoint() is invoked,
it scans the mount table (/proc/mounts) looking for a match. If found,
it is cached. The price to scan /proc/mounts is paid once if the mount
is found.

When the mount point is not found, subsequent calls to xxx_mountpoint()
scan /proc/mounts over and over again.  There is no caching.

This causes a scaling issue in perf record with hugeltbfs__mountpoint().
The function is called for each process found in
synthesize__mmap_events().  If the machine has thousands of processes
and if the /proc/mounts has many entries this could cause major overhead
in perf record. We have observed multi-second slowdowns on some
configurations.

As an example on a laptop:

Before:

  $ sudo umount /dev/hugepages
  $ strace -e trace=openat -o /tmp/tt perf record -a ls
  $ fgrep mounts /tmp/tt
  285

After:

  $ sudo umount /dev/hugepages
  $ strace -e trace=openat -o /tmp/tt perf record -a ls
  $ fgrep mounts /tmp/tt
  1

One could argue that the non-caching in case the moint point is not
found is intentional. That way subsequent calls may discover a moint
point if the sysadmin mounts the filesystem. But the same argument could
be made against caching the mount point. It could be unmounted causing
errors.  It all depends on the intent of the interface. This patch
assumes it is expected to scan /proc/mounts once. The patch documents
the caching behavior in the fs.h header file.

An alternative would be to just fix perf record. But it would solve the
problem with hugetlbs__mountpoint() but there could be similar issues
(possibly down the line) with other xxx_mountpoint() calls in perf or
other tools.

Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200402154357.107873-3-irogers@google.com
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:12 -03:00
Ian Rogers
2a4b51666a perf bench: Add event synthesis benchmark
Event synthesis may occur at the start or end (tail) of a perf command.
In system-wide mode it can scan every process in /proc, which may add
seconds of latency before event recording. Add a new benchmark that
times how long event synthesis takes with and without data synthesis.

An example execution looks like:

 $ perf bench internals synthesize
 # Running 'internals/synthesize' benchmark:
 Average synthesis took: 168.253800 usec
 Average data synthesis took: 208.104700 usec

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200402154357.107873-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:12 -03:00
Adrian Hunter
1a2725f3ee perf script: Simplify auxiliary event printing functions
This simplifies the print functions for the following perf script
options:

	--show-task-events
	--show-namespace-events
	--show-cgroup-events
	--show-mmap-events
	--show-switch-events
	--show-lost-events
	--show-bpf-events

Example:
	# perf record --switch-events -a -e cycles -c 10000 sleep 1
 Before:
	# perf script --show-task-events --show-namespace-events --show-cgroup-events --show-mmap-events --show-switch-events --show-lost-events --show-bpf-events > out-before.txt
 After:
	# perf script --show-task-events --show-namespace-events --show-cgroup-events --show-mmap-events --show-switch-events --show-lost-events --show-bpf-events > out-after.txt
	# diff -s out-before.txt out-after.txt
	Files out-before.txt and out-after.tx are identical

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200402141548.21283-1-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:12 -03:00
Alexey Budankov
025b16f81d doc/admin-guide: update kernel.rst with CAP_PERFMON information
Update the kernel.rst documentation file with the information related to
usage of CAP_PERFMON capability to secure performance monitoring and
observability operations in system.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/84c32383-14a2-fa35-16b6-f9e59bd37240@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:12 -03:00
Alexey Budankov
902a8dcc5b doc/admin-guide: Update perf-security.rst with CAP_PERFMON information
Update perf-security.rst documentation file with the information
related to usage of CAP_PERFMON capability to secure performance
monitoring and observability operations in system.

Committer notes:

While testing 'perf top' under cap_perfmon I noticed that it needs
some more capability and Alexey pointed out cap_ipc_lock, as needed by
this kernel chunk:

  kernel/events/core.c: 6101
       if ((locked > lock_limit) && perf_is_paranoid() &&
               !capable(CAP_IPC_LOCK)) {
               ret = -EPERM;
               goto unlock;
       }

So I added it to the documentation, and also mentioned that if the
libcap version doesn't yet supports 'cap_perfmon', its numeric value can
be used instead, i.e. if:

	# setcap "cap_perfmon,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf

Fails, try:

	# setcap "38,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf

I also added a paragraph stating that using an unpatched libcap will
fail the check for CAP_PERFMON, as it checks the cap number against a
maximum to see if it is valid, which makes it use as the default the
'cycles:u' event, even tho a cap_perfmon capable perf binary can get
kernel samples, to workaround that just use, e.g.:

  # perf top -e cycles
  # perf record -e cycles

And it will sample kernel and user modes.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/17278551-9399-9ebe-d665-8827016a217d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:10 -03:00
Alexey Budankov
ab76878bb7 drivers/oprofile: Open access for CAP_PERFMON privileged process
Open access to monitoring for CAP_PERFMON privileged process.  Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/691f1096-b15f-9b12-50a0-c2b93918149e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:09 -03:00
Alexey Budankov
cea7d0d4a5 drivers/perf: Open access for CAP_PERFMON privileged process
Open access to monitoring for CAP_PERFMON privileged process.  Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/4ec1d6f7-548c-8d1c-f84a-cebeb9674e4e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:09 -03:00
Alexey Budankov
cf91baf3f7 parisc/perf: open access for CAP_PERFMON privileged process
Open access to monitoring for CAP_PERFMON privileged process.  Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/8cc98809-d35b-de0f-de02-4cf554f3cf62@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:08 -03:00
Alexey Budankov
ff46758313 powerpc/perf: open access for CAP_PERFMON privileged process
Open access to monitoring for CAP_PERFMON privileged process.  Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/ac98cd9f-b59e-673c-c70d-180b3e7695d2@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:08 -03:00
Alexey Budankov
031258da05 trace/bpf_trace: Open access for CAP_PERFMON privileged process
Open access to bpf_trace monitoring for CAP_PERFMON privileged process.
Providing the access under CAP_PERFMON capability singly, without the
rest of CAP_SYS_ADMIN credentials, excludes chances to misuse the
credentials and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to bpf_trace monitoring
remains open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN
usage for secure bpf_trace monitoring is discouraged with respect to
CAP_PERFMON capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/c0a0ae47-8b6e-ff3e-416b-3cd1faaf71c0@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:08 -03:00
Alexey Budankov
4e3d3456b7 drm/i915/perf: Open access for CAP_PERFMON privileged process
Open access to i915_perf monitoring for CAP_PERFMON privileged process.
Providing the access under CAP_PERFMON capability singly, without the
rest of CAP_SYS_ADMIN credentials, excludes chances to misuse the
credentials and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to i915_events subsystem remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure i915_events monitoring is discouraged with respect to CAP_PERFMON
capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/e3e3292f-f765-ea98-e59c-fbe2db93fd34@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:08 -03:00
Alexey Budankov
6b3e0e2e04 perf tools: Support CAP_PERFMON capability
Extend error messages to mention CAP_PERFMON capability as an option to
substitute CAP_SYS_ADMIN capability for secure system performance
monitoring and observability operations. Make
perf_event_paranoid_check() and __cmd_ftrace() to be aware of
CAP_PERFMON capability.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to perf_events subsystem remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure perf_events monitoring is discouraged with respect to CAP_PERFMON
capability.

Committer testing:

Using a libcap with this patch:

  diff --git a/libcap/include/uapi/linux/capability.h b/libcap/include/uapi/linux/capability.h
  index 78b2fd4c8a95..89b5b0279b60 100644
  --- a/libcap/include/uapi/linux/capability.h
  +++ b/libcap/include/uapi/linux/capability.h
  @@ -366,8 +366,9 @@ struct vfs_ns_cap_data {

   #define CAP_AUDIT_READ       37

  +#define CAP_PERFMON	     38

  -#define CAP_LAST_CAP         CAP_AUDIT_READ
  +#define CAP_LAST_CAP         CAP_PERFMON

   #define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)

Note that using '38' in place of 'cap_perfmon' works to some degree with
an old libcap, its only when cap_get_flag() is called that libcap
performs an error check based on the maximum value known for
capabilities that it will fail.

This makes determining the default of perf_event_attr.exclude_kernel to
fail, as it can't determine if CAP_PERFMON is in place.

Using 'perf top -e cycles' avoids the default check and sets
perf_event_attr.exclude_kernel to 1.

As root, with a libcap supporting CAP_PERFMON:

  # groupadd perf_users
  # adduser perf -g perf_users
  # mkdir ~perf/bin
  # cp ~acme/bin/perf ~perf/bin/
  # chgrp perf_users ~perf/bin/perf
  # setcap "cap_perfmon,cap_sys_ptrace,cap_syslog=ep" ~perf/bin/perf
  # getcap ~perf/bin/perf
  /home/perf/bin/perf = cap_sys_ptrace,cap_syslog,cap_perfmon+ep
  # ls -la ~perf/bin/perf
  -rwxr-xr-x. 1 root perf_users 16968552 Apr  9 13:10 /home/perf/bin/perf

As the 'perf' user in the 'perf_users' group:

  $ perf top -a --stdio
  Error:
  Failed to mmap with 1 (Operation not permitted)
  $

Either add the cap_ipc_lock capability to the perf binary or reduce the
ring buffer size to some smaller value:

  $ perf top -m10 -a --stdio
  rounding mmap pages size to 64K (16 pages)
  Error:
  Failed to mmap with 1 (Operation not permitted)
  $ perf top -m4 -a --stdio
  Error:
  Failed to mmap with 1 (Operation not permitted)
  $ perf top -m2 -a --stdio
   PerfTop: 762 irqs/sec  kernel:49.7%  exact: 100.0% lost: 0/0 drop: 0/0 [4000Hz cycles], (all, 4 CPUs)
  ------------------------------------------------------------------------------------------------------

     9.83%  perf                [.] __symbols__insert
     8.58%  perf                [.] rb_next
     5.91%  [kernel]            [k] module_get_kallsym
     5.66%  [kernel]            [k] kallsyms_expand_symbol.constprop.0
     3.98%  libc-2.29.so        [.] __GI_____strtoull_l_internal
     3.66%  perf                [.] rb_insert_color
     2.34%  [kernel]            [k] vsnprintf
     2.30%  [kernel]            [k] string_nocheck
     2.16%  libc-2.29.so        [.] _IO_getdelim
     2.15%  [kernel]            [k] number
     2.13%  [kernel]            [k] format_decode
     1.58%  libc-2.29.so        [.] _IO_feof
     1.52%  libc-2.29.so        [.] __strcmp_avx2
     1.50%  perf                [.] rb_set_parent_color
     1.47%  libc-2.29.so        [.] __libc_calloc
     1.24%  [kernel]            [k] do_syscall_64
     1.17%  [kernel]            [k] __x86_indirect_thunk_rax

  $ perf record -a sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.552 MB perf.data (74 samples) ]
  $ perf evlist
  cycles
  $ perf evlist -v
  cycles: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
  $ perf report | head -20
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 74  of event 'cycles'
  # Event count (approx.): 15694834
  #
  # Overhead  Command          Shared Object               Symbol
  # ........  ...............  ..........................  ......................................
  #
      19.62%  perf             [kernel.vmlinux]            [k] strnlen_user
      13.88%  swapper          [kernel.vmlinux]            [k] intel_idle
      13.83%  ksoftirqd/0      [kernel.vmlinux]            [k] pfifo_fast_dequeue
      13.51%  swapper          [kernel.vmlinux]            [k] kmem_cache_free
       6.31%  gnome-shell      [kernel.vmlinux]            [k] kmem_cache_free
       5.66%  kworker/u8:3+ix  [kernel.vmlinux]            [k] delay_tsc
       4.42%  perf             [kernel.vmlinux]            [k] __set_cpus_allowed_ptr
       3.45%  kworker/2:1-eve  [kernel.vmlinux]            [k] shmem_truncate_range
       2.29%  gnome-shell      libgobject-2.0.so.0.6000.7  [.] g_closure_ref
  $

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/a66d5648-2b8e-577e-e1f2-1d56c017ab5e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:08 -03:00