linux.git/tools/perf/util/sort.c, branch v6.9

perf report: Prevent segfault with --no-parent

2024-02-02T06:15:31+00:00

Prevent a perf report segfault with the (non sensical) --no-parent
option

Signed-off-By: Andi Kleen 
Acked-by: Namhyung 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240130185552.150578-1-ak@linux.intel.com

perf annotate: Add --data-type option

2023-12-24T01:39:43+00:00

Support data type annotation with new --data-type option.  It internally
uses type sort key to collect sample histogram for the type and display
every members like below.

  $ perf annotate --data-type
  ...
  Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
  ============================================================================
      samples     offset       size  field
           13          0        640  struct cfs_rq         {
            2          0         16      struct load_weight       load {
            2          0          8          unsigned long        weight;
            0          8          4          u32  inv_weight;
                                         };
            0         16          8      unsigned long    runnable_weight;
            0         24          4      unsigned int     nr_running;
            1         28          4      unsigned int     h_nr_running;
  ...

For simplicity it prints the number of samples per field for now.
But it should be easy to show the overhead percentage instead.

The number at the outer struct is a sum of the numbers of the inner
members.  For example, struct cfs_rq got total 13 samples, and 2 came
from the load (struct load_weight) and 1 from h_nr_running.  Similarly,
the struct load_weight got total 2 samples and they all came from the
weight field.

I've added two new flags in the symbol_conf for this.  The
annotate_data_member is to get the members of the type.  This is also
needed for perf report with typeoff sort key.  The annotate_data_sample
is to update sample stats for each offset and used only in annotate.

Currently it only support stdio output mode, TUI support can be added
later.

Committer testing:

With the perf.data from the previous csets, a very simple, short
duration one:

  # perf annotate --data-type
  Annotate type: 'struct list_head' in [kernel.kallsyms] (1 samples):
  ============================================================================
      samples     offset       size  field
            1          0         16  struct list_head      {
            0          0          8      struct list_head*        next;
            1          8          8      struct list_head*        prev;
                                     };

  Annotate type: 'char' in [kernel.kallsyms] (1 samples):
  ============================================================================
      samples     offset       size  field
            1          0          1  char ;

  #

Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-15-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Add 'symoff' sort key

2023-12-24T01:39:42+00:00

The symoff sort key is to print symbol and offset of sample.  This is
useful for data type profiling to show exact instruction in the function
which refers the data.

  $ perf report -s type,sym,typeoff,symoff --hierarchy
  ...
  #       Overhead  Data Type / Symbol / Data Type Offset / Symbol Offset
  # ..............  .....................................................
  #
      1.23%         struct cfs_rq
        0.84%         update_blocked_averages
          0.19%         struct cfs_rq +336 (leaf_cfs_rq_list.next)
             0.19%         [k] update_blocked_averages+0x96
          0.19%         struct cfs_rq +0 (load.weight)
             0.14%         [k] update_blocked_averages+0x104
             0.04%         [k] update_blocked_averages+0x31c
          0.17%         struct cfs_rq +404 (throttle_count)
             0.12%         [k] update_blocked_averages+0x9d
             0.05%         [k] update_blocked_averages+0x1f9
          0.08%         struct cfs_rq +272 (propagate)
             0.07%         [k] update_blocked_averages+0x3d3
             0.02%         [k] update_blocked_averages+0x45b
  ...

Committer testing:

  # perf report --stdio -s type,typeoff,symoff
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 4  of event 'cpu_atom/mem-loads,ldlat=30/P'
  # Event count (approx.): 7
  #
  # Overhead  Data Type  Data Type Offset  Symbol Offset
  # ........  .........  ................  .............
  #
      42.86%  struct list_head  struct list_head +8 (prev)  [k] __list_del_entry_valid_or_report+0x7
      28.57%  (unknown)  (unknown) +0 (no field)  [.] _nl_intern_locale_data+0x25
      14.29%  char       char +0 (no field)  [k] strncpy_from_user+0xa5
      14.29%  (unknown)  (unknown) +0 (no field)  [.] _dl_lookup_symbol_x+0x50

  #
  # (Tip: To change sampling frequency to 100 Hz: perf record -F 100)
  #

Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-14-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Add 'typeoff' sort key

2023-12-24T01:39:42+00:00

The typeoff sort key shows the data type name, offset and the name of
the field.  This is useful to see which field in the struct is accessed
most frequently.

  $ perf report -s type,typeoff --hierarchy --stdio
  ...
  #     Overhead  Data Type / Data Type Offset
  # ............  ............................
  #
  ...
        1.23%     struct cfs_rq
           0.19%    struct cfs_rq +404 (throttle_count)
           0.19%    struct cfs_rq +0 (load.weight)
           0.19%    struct cfs_rq +336 (leaf_cfs_rq_list.next)
           0.09%    struct cfs_rq +272 (propagate)
           0.09%    struct cfs_rq +196 (removed.nr)
           0.09%    struct cfs_rq +80 (curr)
           0.09%    struct cfs_rq +544 (lt_b_children_throttled)
           0.06%    struct cfs_rq +320 (rq)

Committer testing:

Again with the perf.data from the previous csets:

  # perf report --stdio -s type,typeoff
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 4  of event 'cpu_atom/mem-loads,ldlat=30/P'
  # Event count (approx.): 7
  #
  # Overhead  Data Type  Data Type Offset
  # ........  .........  ................
  #
      42.86%  struct list_head  struct list_head +8 (prev)
      42.86%  (unknown)  (unknown) +0 (no field)
      14.29%  char       char +0 (no field)

  #
  # (Tip: To see callchains in a more compact form: perf report -g folded)
  #
  # perf report --stdio -s dso,type,typeoff
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 4  of event 'cpu_atom/mem-loads,ldlat=30/P'
  # Event count (approx.): 7
  #
  # Overhead  Shared Object         Data Type  Data Type Offset
  # ........  ....................  .........  ................
  #
      42.86%  [kernel.kallsyms]     struct list_head  struct list_head +8 (prev)
      28.57%  libc.so.6             (unknown)  (unknown) +0 (no field)
      14.29%  [kernel.kallsyms]     char       char +0 (no field)
      14.29%  ld-linux-x86-64.so.2  (unknown)  (unknown) +0 (no field)

  #
  # (Tip: If you have debuginfo enabled, try: perf report -s sym,srcline)
  #
  #

Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-13-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf annotate-data: Add member field in the data type

2023-12-24T01:39:42+00:00

Add child member field if the current type is a composite type like a
struct or union.  The member fields are linked in the children list and
do the same recursively if the child itself is a composite type.

Add 'self' member to the annotated_data_type to handle the members in
the same way.

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-11-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Add 'type' sort key

2023-12-24T01:39:42+00:00

The 'type' sort key is to aggregate hist entries by data type they
access.  Add mem_type field to hist_entry struct to save the type.  If
hist_entry__get_data_type() returns NULL, it'd use the 'unknown_type'
instance.

Committer testing:

Before:

  # perf mem record  sleep 2s
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.037 MB perf.data (4 samples) ]
  root@number:/home/acme/Downloads# perf report --stdio -s type
  Error:
  Unknown --sort key: `type'
   Usage: perf report []

      -s, --sort 
                            sort by key(s): overhead overhead_sys overhead_us overhead_guest_sys
                            overhead_guest_us overhead_children sample period
                            pid comm dso symbol parent cpu socket srcline srcfile
                            local_weight weight transaction trace symbol_size
                            dso_size cgroup cgroup_id ipc_null time code_page_size
                            local_ins_lat ins_lat local_p_stage_cyc p_stage_cyc
                            addr local_retire_lat retire_lat simd dso_from dso_to
                            symbol_from symbol_to mispredict abort in_tx cycles
                            srcline_from srcline_to ipc_lbr addr_from addr_to
                            symbol_daddr dso_daddr locked tlb mem snoop dcacheline
                            symbol_iaddr phys_daddr data_page_size blocked
  #

After:

  # perf report --stdio -s type
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 4  of event 'cpu_atom/mem-loads,ldlat=30/P'
  # Event count (approx.): 7
  #
  # Overhead  Data Type
  # ........  .........
  #
     100.00%  (unknown)

  #
  # (Tip: Print event counts in CSV format with: perf stat -x,)
  #
  # rpm -q kernel-debuginfo
  kernel-debuginfo-6.6.4-200.fc39.x86_64
  # uname -r
  6.6.4-200.fc39.x86_64
  #

Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Cc: linux-toolchains@vger.kernel.org>
Cc: linux-trace-devel@vger.kernel.org>
Link: https://lore.kernel.org/r/20231213001323.718046-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Split branch stack cycles info from 'struct annotation'

2023-11-09T16:49:33+00:00

The cycles info is only meaningful when sample has branch stacks.  To
save the memory for normal cases, move those fields to a new 'struct
annotated_branch' and dynamically allocate it when needed.  Also move
cycles_hist from annotated_source as it's related here.

Signed-off-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Christophe JAILLET 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20231103191907.54531-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

libperf rc_check: Add RC_CHK_EQUAL

2023-10-25T20:37:22+00:00

Comparing pointers with reference count checking is tricky to avoid a
SEGV. Add a convenience macro to simplify and use.

Signed-off-by: Ian Rogers 
Cc: K Prateek Nayak 
Cc: Ravi Bangoria 
Cc: Sandipan Das 
Cc: Anshuman Khandual 
Cc: German Gomez 
Cc: James Clark 
Cc: Nick Terrell 
Cc: Sean Christopherson 
Cc: Changbin Du 
Cc: liuwenyu 
Cc: Yang Jihong 
Cc: Masami Hiramatsu 
Cc: Miguel Ojeda 
Cc: Song Liu 
Cc: Leo Yan 
Cc: Kajol Jain 
Cc: Andi Kleen 
Cc: Kan Liang 
Cc: Athira Rajeev 
Cc: Yanteng Si 
Cc: Liam Howlett 
Cc: Paolo Bonzini 
Link: https://lore.kernel.org/r/20231024222353.3024098-5-irogers@google.com
Signed-off-by: Namhyung Kim

perf srcline: Optimize comparision against SRCLINE_UNKNOWN

2023-06-12T21:17:00+00:00

This is a string constant that gets returned and then strcmp() around,
we can instead just do a pointer comparision.

That requires a new global variable to comply with these warnings from
some versions of clang and gcc:

  41    68.95 fedora:rawhide                : FAIL clang version 16.0.4 (Fedora 16.0.4-1.fc39)
    result of comparison against a string literal is unspecified (use an explicit string comparison function instead) [-Werror,-Wstring-compare]
            if (start_line != SRCLINE_UNKNOWN &&
                           ^  ~~~~~~~~~~~~~~~  41

Ack comments:

Agreed, the strcmps make me nervous as they won't distinguish heap from
a global meaning we could end up with things like pointers to freed
memory. The comparison with the global is always going to be same imo.

Acked-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Brian Robbins 
Cc: Changbin Du 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Ivan Babrou 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Miguel Ojeda 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Wenyu Liu 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Ye Xingchen 
Cc: Yuan Can 
Link: https://lore.kernel.org/lkml/ZIcoJytUEz4UgQYR@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf thread: Add reference count checking

2023-06-12T18:57:53+00:00

Modify struct declaration and accessor functions for the reference
count checkers additional layer of indirection. Make sure pid_cmp in
builtin-sched.c uses the underlying/original struct in pointer
arithmetic, and not the temporary get/put indirection.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Brian Robbins 
Cc: Changbin Du 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Ivan Babrou 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Miguel Ojeda 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Wenyu Liu 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Ye Xingchen 
Cc: Yuan Can 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230608232823.4027869-8-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo