Re: [PATCH 18/52] perf report: Add 'type' sort key

[Namhyung Kim <namhyung@kernel.org>]

On Tue, Nov 21, 2023 at 9:55 AM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Thu, Nov 09, 2023 at 03:59:37PM -0800, Namhyung Kim escreveu:
> > 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.
>
> I built up to here and then tried on a random perf.data file:
>
> ⬢[acme@toolbox perf-tools-next]$ perf evlist
> cycles:Pu
> ⬢[acme@toolbox perf-tools-next]$ perf evlist -v
> cycles:Pu: type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0 (PERF_COUNT_HW_CPU_CYCLES), { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|PERIOD, read_format: ID|LOST, disabled: 1, inherit: 1, exclude_kernel: 1, exclude_hv: 1, mmap: 1, comm: 1, freq: 1, enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
> ⬢[acme@toolbox perf-tools-next]$
>
> And got:
>
> ⬢[acme@toolbox perf-tools-next]$ perf report -s type
> perf: Segmentation fault
> -------- backtrace --------
> perf[0x69f743]
> /lib64/libc.so.6(+0x3dbb0)[0x7f89b4778bb0]
> perf[0x505af6]
> perf[0x512d47]
> perf[0x512f82]
> perf[0x5b3461]
> perf[0x5b3516]
> perf[0x5b3a3e]
> perf[0x5bbb05]
> perf[0x5bc68f]
> perf[0x5bca7c]
> perf[0x42ead1]
> perf[0x42fa08]
> perf[0x43200d]
> perf[0x504856]
> perf[0x504ac5]
> perf[0x504c14]
> perf[0x504f01]
> /lib64/libc.so.6(+0x27b8a)[0x7f89b4762b8a]
> /lib64/libc.so.6(__libc_start_main+0x8b)[0x7f89b4762c4b]
> perf[0x40ed65]
> ⬢[acme@toolbox perf-tools-next]$

Right, the 'type' sort key was added here but unfortunately
it's not ready for prime time yet.  It also needs the next patch
19/52 ("perf report: Support data type profiling") to fully enable
the feature.  Do you think it's better to squash into here?

Thanks,
Namhyung

>
> Using gdb:
>
> (gdb) run report --stdio -s type
> Starting program: /home/acme/bin/perf report --stdio -s type
>
> This GDB supports auto-downloading debuginfo from the following URLs:
>   <https://debuginfod.fedoraproject.org/>
> Enable debuginfod for this session? (y or [n]) y
> Debuginfod has been enabled.
> To make this setting permanent, add 'set debuginfod enabled on' to .gdbinit.
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib64/libthread_db.so.1".
> [Detaching after fork from child process 811109]
>
> Program received signal SIGSEGV, Segmentation fault.
> 0x0000000000505af6 in list_empty (head=0x14c20) at /home/acme/git/perf-tools-next/tools/include/linux/list.h:189
> 189             return head->next == head;
> (gdb) bt
> #0  0x0000000000505af6 in list_empty (head=0x14c20) at /home/acme/git/perf-tools-next/tools/include/linux/list.h:189
> #1  0x0000000000512d47 in symbol__ensure_annotate (ms=0xe6f258, evsel=0xe276f0) at util/annotate.c:3640
> #2  0x0000000000512f82 in hist_entry__get_data_type (he=0xe6f1e0) at util/annotate.c:3696
> #3  0x00000000005b3461 in sort__type_init (he=0xe6f1e0) at util/sort.c:2152
> #4  0x00000000005b3516 in sort__type_collapse (left=0xe6ed80, right=0xe6f1e0) at util/sort.c:2169
> #5  0x00000000005b3a3e in __sort__hpp_collapse (fmt=0xe448f0, a=0xe6ed80, b=0xe6f1e0) at util/sort.c:2394
> #6  0x00000000005bbb05 in hist_entry__collapse (left=0xe6ed80, right=0xe6f1e0) at util/hist.c:1306
> #7  0x00000000005bc68f in hists__collapse_insert_entry (hists=0xe27960, root=0xe27998, he=0xe6f1e0) at util/hist.c:1613
> #8  0x00000000005bca7c in hists__collapse_resort (hists=0xe27960, prog=0x7fffffffb820) at util/hist.c:1697
> #9  0x000000000042ead1 in report__collapse_hists (rep=0x7fffffffbac0) at builtin-report.c:723
> #10 0x000000000042fa08 in __cmd_report (rep=0x7fffffffbac0) at builtin-report.c:1042
> #11 0x000000000043200d in cmd_report (argc=0, argv=0x7fffffffe1b0) at builtin-report.c:1733
> #12 0x0000000000504856 in run_builtin (p=0xdf7da0 <commands+288>, argc=4, argv=0x7fffffffe1b0) at perf.c:322
> #13 0x0000000000504ac5 in handle_internal_command (argc=4, argv=0x7fffffffe1b0) at perf.c:375
> #14 0x0000000000504c14 in run_argv (argcp=0x7fffffffdfcc, argv=0x7fffffffdfc0) at perf.c:419
> #15 0x0000000000504f01 in main (argc=4, argv=0x7fffffffe1b0) at perf.c:535
> (gdb)
>
>
> static void symbol__ensure_annotate(struct map_symbol *ms, struct evsel *evsel)
> +{
> +       struct disasm_line *dl, *tmp_dl;
> +       struct annotation *notes;
> +
> +       notes = symbol__annotation(ms->sym);
> +       if (!list_empty(&notes->src->source))
> +               return;
> +
> +       if (symbol__annotate(ms, evsel, notes->options, NULL) < 0)
> +               return;
> +
> +       /* remove non-insn disasm lines for simplicity */
> +       list_for_each_entry_safe(dl, tmp_dl, &notes->src->source, al.node) {
> +               if (dl->al.offset == -1) {
> +                       list_del(&dl->al.node);
> +                       free(dl);
> +               }
> +       }
> +}
>
> Probably annotated_source__new() wasn't called? Yeah, seems so:
>
> (gdb) b annotated_source__new
> Breakpoint 1 at 0x50a894: file util/annotate.c, line 851.
> (gdb) run report --stdio -s type
> Starting program: /home/acme/bin/perf report --stdio -s type
>
> This GDB supports auto-downloading debuginfo from the following URLs:
>   <https://debuginfod.fedoraproject.org/>
> Enable debuginfod for this session? (y or [n]) y
> Debuginfod has been enabled.
> To make this setting permanent, add 'set debuginfod enabled on' to .gdbinit.
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib64/libthread_db.so.1".
> [Detaching after fork from child process 818292]
>
> Program received signal SIGSEGV, Segmentation fault.
> 0x0000000000505af6 in list_empty (head=0x14c20) at /home/acme/git/perf-tools-next/tools/include/linux/list.h:189
> 189             return head->next == head;
> (gdb)