[PATCH 2/3] perf hists: Move locking to its call-sites

From: Namhyung Kim
Date: Mon May 13 2013 - 02:17:02 EST


From: Namhyung Kim <namhyung.kim@xxxxxxx>

It's a preparation patch to eliminate unneeded locking in the perf
report path.

Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/builtin-report.c | 26 ++++++++++++++------------
tools/perf/builtin-top.c | 3 +++
tools/perf/util/hist.c | 6 +-----
3 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index d45bf9b0361d..63febd24e912 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -297,6 +297,7 @@ static int process_sample_event(struct perf_tool *tool,
{
struct perf_report *rep = container_of(tool, struct perf_report, tool);
struct addr_location al;
+ int ret;

if (perf_event__preprocess_sample(event, machine, &al, sample,
rep->annotate_init) < 0) {
@@ -311,28 +312,29 @@ static int process_sample_event(struct perf_tool *tool,
if (rep->cpu_list && !test_bit(sample->cpu, rep->cpu_bitmap))
return 0;

+ pthread_mutex_lock(&evsel->hists.lock);
+
if (sort__mode == SORT_MODE__BRANCH) {
- if (perf_report__add_branch_hist_entry(tool, &al, sample,
- evsel, machine)) {
+ ret = perf_report__add_branch_hist_entry(tool, &al, sample,
+ evsel, machine);
+ if (ret < 0)
pr_debug("problem adding lbr entry, skipping event\n");
- return -1;
- }
} else if (rep->mem_mode == 1) {
- if (perf_report__add_mem_hist_entry(tool, &al, sample,
- evsel, machine, event)) {
+ ret = perf_report__add_mem_hist_entry(tool, &al, sample,
+ evsel, machine, event);
+ if (ret < 0)
pr_debug("problem adding mem entry, skipping event\n");
- return -1;
- }
} else {
if (al.map != NULL)
al.map->dso->hit = 1;

- if (perf_evsel__add_hist_entry(evsel, &al, sample, machine)) {
+ ret = perf_evsel__add_hist_entry(evsel, &al, sample, machine);
+ if (ret < 0)
pr_debug("problem incrementing symbol period, skipping event\n");
- return -1;
- }
}
- return 0;
+ pthread_mutex_unlock(&evsel->hists.lock);
+
+ return ret;
}

static int process_read_event(struct perf_tool *tool,
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 5cd41ec43ce1..c2c973476479 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -245,8 +245,11 @@ static struct hist_entry *perf_evsel__add_hist_entry(struct perf_evsel *evsel,
{
struct hist_entry *he;

+ pthread_mutex_lock(&evsel->hists.lock);
he = __hists__add_entry(&evsel->hists, al, NULL, sample->period,
sample->weight);
+ pthread_mutex_unlock(&evsel->hists.lock);
+
if (he == NULL)
return NULL;

diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 7e0fa628e9ab..b11a6cfdb414 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -347,8 +347,6 @@ static struct hist_entry *add_hist_entry(struct hists *hists,
struct hist_entry *he;
int cmp;

- pthread_mutex_lock(&hists->lock);
-
p = &hists->entries_in->rb_node;

while (*p != NULL) {
@@ -394,14 +392,12 @@ static struct hist_entry *add_hist_entry(struct hists *hists,

he = hist_entry__new(entry);
if (!he)
- goto out_unlock;
+ return NULL;

rb_link_node(&he->rb_node_in, parent, p);
rb_insert_color(&he->rb_node_in, hists->entries_in);
out:
hist_entry__add_cpumode_period(he, al->cpumode, period);
-out_unlock:
- pthread_mutex_unlock(&hists->lock);
return he;
}

--
1.7.11.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/