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perf annotate: Remove hist__account_cycles() from callback

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

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

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

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

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

Now, we can try, for example:

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

The before/after output should be no change.

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

 v2:
 ---
 1. Cover the similar perf report
 2. Remove the checking code "ch->reset >= ch->num / 2"

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1552684577-29041-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jin Yao
2019-03-16 05:16:17 +08:00
committed by Arnaldo Carvalho de Melo
parent 6b89d4c1ae
commit bdd1666b3d
3 changed files with 8 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
tools/perf/builtin-annotate.c
View File

@ -159,8 +159,6 @@ static int hist_iter__branch_callback(struct hist_entry_iter *iter,
struct perf_evsel *evsel = iter->evsel;
int err;
hist__account_cycles(sample->branch_stack, al, sample, false);
bi = he->branch_info;
err = addr_map_symbol__inc_samples(&bi->from, sample, evsel);
@ -199,6 +197,8 @@ static int process_branch_callback(struct perf_evsel *evsel,
if (a.map != NULL)
a.map->dso->hit = 1;
hist__account_cycles(sample->branch_stack, al, sample, false);
ret = hist_entry_iter__add(&iter, &a, PERF_MAX_STACK_DEPTH, ann);
return ret;
}