[tip:perf/core] perf annotate: Remove hist__account_cycles() from callback

From: tip-bot for Jin Yao
Date: Sat May 18 2019 - 04:49:01 EST


Commit-ID: bdd1666b3d03d675bdb7f8d92b29f2797acbc5e8
Gitweb: https://git.kernel.org/tip/bdd1666b3d03d675bdb7f8d92b29f2797acbc5e8
Author: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
AuthorDate: Sat, 16 Mar 2019 05:16:17 +0800
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Wed, 15 May 2019 16:36:46 -0300

perf annotate: Remove hist__account_cycles() from callback

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@xxxxxxxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jin Yao <yao.jin@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1552684577-29041-1-git-send-email-yao.jin@xxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-annotate.c | 4 ++--
tools/perf/builtin-report.c | 11 +++++------
tools/perf/util/annotate.c | 2 +-
3 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
index 67f9d9ffacfb..77deb3a40596 100644
--- a/tools/perf/builtin-annotate.c
+++ b/tools/perf/builtin-annotate.c
@@ -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;
}
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 4054eb1f98ac..91e27ac297c2 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -136,9 +136,6 @@ static int hist_iter__report_callback(struct hist_entry_iter *iter,
if (!ui__has_annotation() && !rep->symbol_ipc)
return 0;

- hist__account_cycles(sample->branch_stack, al, sample,
- rep->nonany_branch_mode);
-
if (sort__mode == SORT_MODE__BRANCH) {
bi = he->branch_info;
err = addr_map_symbol__inc_samples(&bi->from, sample, evsel);
@@ -181,9 +178,6 @@ static int hist_iter__branch_callback(struct hist_entry_iter *iter,
if (!ui__has_annotation() && !rep->symbol_ipc)
return 0;

- hist__account_cycles(sample->branch_stack, al, sample,
- rep->nonany_branch_mode);
-
bi = he->branch_info;
err = addr_map_symbol__inc_samples(&bi->from, sample, evsel);
if (err)
@@ -282,6 +276,11 @@ static int process_sample_event(struct perf_tool *tool,
if (al.map != NULL)
al.map->dso->hit = 1;

+ if (ui__has_annotation() || rep->symbol_ipc) {
+ hist__account_cycles(sample->branch_stack, &al, sample,
+ rep->nonany_branch_mode);
+ }
+
ret = hist_entry_iter__add(&iter, &al, rep->max_stack, rep);
if (ret < 0)
pr_debug("problem adding hist entry, skipping event\n");
diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 09762985c713..0b8573fd9b05 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1021,7 +1021,7 @@ static void annotation__count_and_fill(struct annotation *notes, u64 start, u64
float ipc = n_insn / ((double)ch->cycles / (double)ch->num);

/* Hide data when there are too many overlaps. */
- if (ch->reset >= 0x7fff || ch->reset >= ch->num / 2)
+ if (ch->reset >= 0x7fff)
return;

for (offset = start; offset <= end; offset++) {