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* [PATCH 1/3] perf top: Get rid of *_threaded() functions
@ 2013-05-13  6:16 Namhyung Kim
  2013-05-13  6:16 ` [PATCH 2/3] perf hists: Move locking to its call-sites Namhyung Kim
  2013-05-13  6:16 ` [PATCH 3/3] perf report: Don't be bothered with locking when adding hist entries Namhyung Kim
  0 siblings, 2 replies; 3+ messages in thread
From: Namhyung Kim @ 2013-05-13  6:16 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: Peter Zijlstra, Paul Mackerras, Ingo Molnar, Namhyung Kim, LKML,
	Jiri Olsa, David Ahern, Stephane Eranian, Andi Kleen

From: Namhyung Kim <namhyung.kim@lge.com>

Those _threaded() functions are needed to make hist tree handling
thread-safe, but AFAICS the only thing it does is forcing it to use
the intermediate 'collapsed' tree.  It can be acheived by setting
sort__need_collapse to 1 in cmd_top() so no need to keep those
_threaded() variants.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-top.c | 23 +++++++++++++----------
 tools/perf/util/hist.c   | 44 ++++++--------------------------------------
 tools/perf/util/hist.h   |  4 ----
 3 files changed, 19 insertions(+), 52 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 81adcafbac8f..5cd41ec43ce1 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -284,11 +284,11 @@ static void perf_top__print_sym_table(struct perf_top *top)
 		return;
 	}
 
-	hists__collapse_resort_threaded(&top->sym_evsel->hists);
-	hists__output_resort_threaded(&top->sym_evsel->hists);
-	hists__decay_entries_threaded(&top->sym_evsel->hists,
-				      top->hide_user_symbols,
-				      top->hide_kernel_symbols);
+	hists__collapse_resort(&top->sym_evsel->hists);
+	hists__output_resort(&top->sym_evsel->hists);
+	hists__decay_entries(&top->sym_evsel->hists,
+			     top->hide_user_symbols,
+			     top->hide_kernel_symbols);
 	hists__output_recalc_col_len(&top->sym_evsel->hists,
 				     top->print_entries - printed);
 	putchar('\n');
@@ -549,11 +549,11 @@ static void perf_top__sort_new_samples(void *arg)
 	if (t->evlist->selected != NULL)
 		t->sym_evsel = t->evlist->selected;
 
-	hists__collapse_resort_threaded(&t->sym_evsel->hists);
-	hists__output_resort_threaded(&t->sym_evsel->hists);
-	hists__decay_entries_threaded(&t->sym_evsel->hists,
-				      t->hide_user_symbols,
-				      t->hide_kernel_symbols);
+	hists__collapse_resort(&t->sym_evsel->hists);
+	hists__output_resort(&t->sym_evsel->hists);
+	hists__decay_entries(&t->sym_evsel->hists,
+			     t->hide_user_symbols,
+			     t->hide_kernel_symbols);
 }
 
 static void *display_thread_tui(void *arg)
@@ -1126,6 +1126,9 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
 	if (setup_sorting() < 0)
 		usage_with_options(top_usage, options);
 
+	/* display thread wants entries to be collapsed in a different tree */
+	sort__need_collapse = 1;
+
 	if (top.use_stdio)
 		use_browser = 0;
 	else if (top.use_tui)
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 72b4eec820c3..7e0fa628e9ab 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -240,8 +240,7 @@ static bool hists__decay_entry(struct hists *hists, struct hist_entry *he)
 	return he->stat.period == 0;
 }
 
-static void __hists__decay_entries(struct hists *hists, bool zap_user,
-				   bool zap_kernel, bool threaded)
+void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel)
 {
 	struct rb_node *next = rb_first(&hists->entries);
 	struct hist_entry *n;
@@ -260,7 +259,7 @@ static void __hists__decay_entries(struct hists *hists, bool zap_user,
 		    !n->used) {
 			rb_erase(&n->rb_node, &hists->entries);
 
-			if (sort__need_collapse || threaded)
+			if (sort__need_collapse)
 				rb_erase(&n->rb_node_in, &hists->entries_collapsed);
 
 			hist_entry__free(n);
@@ -269,17 +268,6 @@ static void __hists__decay_entries(struct hists *hists, bool zap_user,
 	}
 }
 
-void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel)
-{
-	return __hists__decay_entries(hists, zap_user, zap_kernel, false);
-}
-
-void hists__decay_entries_threaded(struct hists *hists,
-				   bool zap_user, bool zap_kernel)
-{
-	return __hists__decay_entries(hists, zap_user, zap_kernel, true);
-}
-
 /*
  * histogram, sorted on item, collects periods
  */
@@ -613,13 +601,13 @@ static void hists__apply_filters(struct hists *hists, struct hist_entry *he)
 	hists__filter_entry_by_symbol(hists, he);
 }
 
-static void __hists__collapse_resort(struct hists *hists, bool threaded)
+void hists__collapse_resort(struct hists *hists)
 {
 	struct rb_root *root;
 	struct rb_node *next;
 	struct hist_entry *n;
 
-	if (!sort__need_collapse && !threaded)
+	if (!sort__need_collapse)
 		return;
 
 	root = hists__get_rotate_entries_in(hists);
@@ -641,16 +629,6 @@ static void __hists__collapse_resort(struct hists *hists, bool threaded)
 	}
 }
 
-void hists__collapse_resort(struct hists *hists)
-{
-	return __hists__collapse_resort(hists, false);
-}
-
-void hists__collapse_resort_threaded(struct hists *hists)
-{
-	return __hists__collapse_resort(hists, true);
-}
-
 /*
  * reverse the map, sort on period.
  */
@@ -737,7 +715,7 @@ static void __hists__insert_output_entry(struct rb_root *entries,
 	rb_insert_color(&he->rb_node, entries);
 }
 
-static void __hists__output_resort(struct hists *hists, bool threaded)
+void hists__output_resort(struct hists *hists)
 {
 	struct rb_root *root;
 	struct rb_node *next;
@@ -746,7 +724,7 @@ static void __hists__output_resort(struct hists *hists, bool threaded)
 
 	min_callchain_hits = hists->stats.total_period * (callchain_param.min_percent / 100);
 
-	if (sort__need_collapse || threaded)
+	if (sort__need_collapse)
 		root = &hists->entries_collapsed;
 	else
 		root = hists->entries_in;
@@ -767,16 +745,6 @@ static void __hists__output_resort(struct hists *hists, bool threaded)
 	}
 }
 
-void hists__output_resort(struct hists *hists)
-{
-	return __hists__output_resort(hists, false);
-}
-
-void hists__output_resort_threaded(struct hists *hists)
-{
-	return __hists__output_resort(hists, true);
-}
-
 static void hists__remove_entry_filter(struct hists *hists, struct hist_entry *h,
 				       enum hist_filter filter)
 {
diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
index 6be88dc12b9a..bd81d799a1bf 100644
--- a/tools/perf/util/hist.h
+++ b/tools/perf/util/hist.h
@@ -104,13 +104,9 @@ struct hist_entry *__hists__add_mem_entry(struct hists *self,
 					  u64 weight);
 
 void hists__output_resort(struct hists *self);
-void hists__output_resort_threaded(struct hists *hists);
 void hists__collapse_resort(struct hists *self);
-void hists__collapse_resort_threaded(struct hists *hists);
 
 void hists__decay_entries(struct hists *hists, bool zap_user, bool zap_kernel);
-void hists__decay_entries_threaded(struct hists *hists, bool zap_user,
-				   bool zap_kernel);
 void hists__output_recalc_col_len(struct hists *hists, int max_rows);
 
 void hists__inc_nr_entries(struct hists *hists, struct hist_entry *h);
-- 
1.7.11.7


^ permalink raw reply	[flat|nested] 3+ messages in thread

* [PATCH 2/3] perf hists: Move locking to its call-sites
  2013-05-13  6:16 [PATCH 1/3] perf top: Get rid of *_threaded() functions Namhyung Kim
@ 2013-05-13  6:16 ` Namhyung Kim
  2013-05-13  6:16 ` [PATCH 3/3] perf report: Don't be bothered with locking when adding hist entries Namhyung Kim
  1 sibling, 0 replies; 3+ messages in thread
From: Namhyung Kim @ 2013-05-13  6:16 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: Peter Zijlstra, Paul Mackerras, Ingo Molnar, Namhyung Kim, LKML,
	Jiri Olsa, David Ahern, Stephane Eranian, Andi Kleen

From: Namhyung Kim <namhyung.kim@lge.com>

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

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 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


^ permalink raw reply	[flat|nested] 3+ messages in thread

* [PATCH 3/3] perf report: Don't be bothered with locking when adding hist entries
  2013-05-13  6:16 [PATCH 1/3] perf top: Get rid of *_threaded() functions Namhyung Kim
  2013-05-13  6:16 ` [PATCH 2/3] perf hists: Move locking to its call-sites Namhyung Kim
@ 2013-05-13  6:16 ` Namhyung Kim
  1 sibling, 0 replies; 3+ messages in thread
From: Namhyung Kim @ 2013-05-13  6:16 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: Peter Zijlstra, Paul Mackerras, Ingo Molnar, Namhyung Kim, LKML,
	Jiri Olsa, David Ahern, Stephane Eranian, Andi Kleen

From: Namhyung Kim <namhyung.kim@lge.com>

The perf report is single-threaded, so no need to grab a lock.
Although the fast path of pthread_mutex_[un]lock() is very fast,
there's ~3% gain by eliminating it when we have huge sample data.

  $ perf record -a -F 100000 -o perf.data.bench -- perf bench sched all
  $ perf record -e cycles:upp -o perf.data.before -- \
  > perf report -i perf.data.bench --stdio > /dev/null
  ... apply this patch ...
  $ perf record -e cycles:upp -o perf.data.after -- \
  > perf report -i perf.data.bench --stdio > /dev/null
  $ perf diff perf.data.{before,after} | grep pthread
             +0.02%  libpthread-2.15.so  [.] _pthread_cleanup_push_defer
             +0.02%  libpthread-2.15.so  [.] _pthread_cleanup_pop_restore
     0.05%   -0.05%  perf                [.] pthread_mutex_unlock@plt
     0.05%   -0.05%  perf                [.] pthread_mutex_lock@plt
     1.01%   -1.01%  libpthread-2.15.so  [.] pthread_mutex_lock
     1.68%   -1.68%  libpthread-2.15.so  [.] __pthread_mutex_unlock_usercnt
     0.05%   -0.05%  libpthread-2.15.so  [.] pthread_mutex_unlock

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-report.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 63febd24e912..0f0cf2472d9d 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -312,8 +312,6 @@ 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) {
 		ret = perf_report__add_branch_hist_entry(tool, &al, sample,
 							 evsel, machine);
@@ -332,8 +330,6 @@ static int process_sample_event(struct perf_tool *tool,
 		if (ret < 0)
 			pr_debug("problem incrementing symbol period, skipping event\n");
 	}
-	pthread_mutex_unlock(&evsel->hists.lock);
-
 	return ret;
 }
 
-- 
1.7.11.7


^ permalink raw reply	[flat|nested] 3+ messages in thread

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Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2013-05-13  6:16 [PATCH 1/3] perf top: Get rid of *_threaded() functions Namhyung Kim
2013-05-13  6:16 ` [PATCH 2/3] perf hists: Move locking to its call-sites Namhyung Kim
2013-05-13  6:16 ` [PATCH 3/3] perf report: Don't be bothered with locking when adding hist entries Namhyung Kim

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