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Author SHA1 Message Date
Namhyung Kim
61a9741e9f perf annotate: Add --type-stat option for debugging
The --type-stat option is to be used with --data-type and to print
detailed failure reasons for the data type annotation.

  $ perf annotate --data-type --type-stat
  Annotate data type stats:
  total 294, ok 116 (39.5%), bad 178 (60.5%)
  -----------------------------------------------------------
          30 : no_sym
          40 : no_insn_ops
          33 : no_mem_ops
          63 : no_var
           4 : no_typeinfo
           8 : bad_offset

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-17-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-12-23 22:40:13 -03:00
Namhyung Kim
9bd7ddd157 perf annotate-data: Update sample histogram for type
The annotated_data_type__update_samples() to get histogram for data type
access.

It'll be called by perf annotate to show which fields in the data type
are accessed frequently.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-12-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-12-23 22:39:42 -03:00
Namhyung Kim
4a111cadac perf annotate-data: Add member field in the data type
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 <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
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 <acme@redhat.com>
2023-12-23 22:39:42 -03:00
Namhyung Kim
2f2c41bdd8 perf report: Add 'type' sort key
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 [<options>]

      -s, --sort <key[,key2...]>
                            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 <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
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 <acme@redhat.com>
2023-12-23 22:39:42 -03:00
Namhyung Kim
fc044c53b9 perf annotate-data: Add dso->data_types tree
To aggregate accesses to the same data type, add 'data_types' tree in
DSO to maintain data types and find it by name and size.

It might have different data types that happen to have the same name,
so it also compares the size of the type.

Even if it doesn't 100% guarantee, it reduces the possibility of
mis-handling of such conflicts.

And I don't think it's common to have different types with the same
name.

Committer notes:

Very few cases on the Linux kernel, but there are some different types
with the same name, unsure if there is a debug mode in libbpf dedup that
warns about such cases, but there are provisions in pahole for that,
see:

  "emit: Notice type shadowing, i.e. multiple types with the same name (enum, struct, union, etc)"
    https://git.kernel.org/pub/scm/devel/pahole/pahole.git/commit/?id=4f332dbfd02072e4f410db7bdcda8d6e3422974b

  $ pahole --compile > vmlinux.h
  $ rm -f a ; make a
  cc     a.c   -o a
  $ grep __[0-9] vmlinux.h
  union irte__1 {
  struct map_info__1;
  struct map_info__1 {
  	struct map_info__1 *       next;                 /*     0     8 */
  $

  drivers/iommu/amd/amd_iommu_types.h 'union irte'
  include/linux/dmar.h                'struct irte'

  include/linux/device-mapper.h:

    union map_info {
            void *ptr;
    };

  include/linux/mtd/map.h:

    struct map_info {
        const char *name;
        unsigned long size;
        resource_size_t phys;
   <SNIP>

  kernel/events/uprobes.c:

   struct map_info {
        struct map_info *next;
        struct mm_struct *mm;
        unsigned long vaddr;
  };

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-12-23 22:39:42 -03:00
Namhyung Kim
b9c87f536c perf annotate-data: Add find_data_type() to get type from memory access
The find_data_type() is to get a data type from the memory access at the
given address (IP) using a register and an offset.

It requires DWARF debug info in the DSO and searches the list of
variables and function parameters in the scope.

In a pseudo code, it does basically the following:

  find_data_type(dso, ip, reg, offset)
  {
      pc = map__rip_2objdump(ip);
      CU = dwarf_addrdie(dso->dwarf, pc);
      scopes = die_get_scopes(CU, pc);
      for_each_scope(S, scopes) {
          V = die_find_variable_by_reg(S, pc, reg);
          if (V && V.type == pointer_type) {
              T = die_get_real_type(V);
              if (offset < T.size)
                  return T;
          }
      }
      return NULL;
  }

Committer notes:

The 'size' variable in check_variable() is 64-bit, so use PRIu64 and
inttypes.h to debug it.

Ditto at find_data_type_die().

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: linux-toolchains@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Link: https://lore.kernel.org/r/20231213001323.718046-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-12-23 22:39:18 -03:00