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* [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2)
@ 2022-01-27  0:00 Namhyung Kim
  2022-01-27  0:00 ` [PATCH 1/6] perf lock: Convert lockhash_table to use hlist Namhyung Kim
                   ` (6 more replies)
  0 siblings, 7 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

Hello,

I have some updates in the perf lock command (focused on 'report').
The main change is to add -c (or --combine-locks) option to aggregate
results based on lock class name.

 * changes from v1)
  - rebased onto recent acme/perf/core
  - add Jiri's Acked-by

Without this option, the result deals with lock addresses so instances
in the same lock class will have separate entries like below:

  # perf lock report
                  Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns) 

         rcu_read_lock     251225          0               0               0               0               0 
   &(ei->i_block_re...       8731          0               0               0               0               0 
   &sb->s_type->i_l...       8731          0               0               0               0               0 
   hrtimer_bases.lo...       5261          0               0               0               0               0 
   hrtimer_bases.lo...       2626          0               0               0               0               0 
   hrtimer_bases.lo...       1953          0               0               0               0               0 
   hrtimer_bases.lo...       1382          0               0               0               0               0 
   cpu_hotplug_lock...       1350          0               0               0               0               0 
   hrtimer_bases.lo...       1273          0               0               0               0               0 
   hrtimer_bases.lo...       1269          0               0               0               0               0 
   hrtimer_bases.lo...       1198          0               0               0               0               0 
   hrtimer_bases.lo...       1116          0               0               0               0               0 
           &base->lock       1109          0               0               0               0               0 
   hrtimer_bases.lo...       1067          0               0               0               0               0 
   hrtimer_bases.lo...       1052          0               0               0               0               0 
   hrtimer_bases.lo...        957          0               0               0               0               0 
   hrtimer_bases.lo...        948          0               0               0               0               0 
          css_set_lock        791          0               0               0               0               0 
   hrtimer_bases.lo...        752          0               0               0               0               0 
   &lruvec->lru_loc...        747          5           11254           56272           18317            1412 
   hrtimer_bases.lo...        738          0               0               0               0               0 
   &newf->file_lock...        706         15            1025           15388            2279             618 
   hrtimer_bases.lo...        702          0               0               0               0               0 
   hrtimer_bases.lo...        694          0               0               0               0               0 
  ...

With -c option, the hrtimer_bases.lock would be combined into a single
entry.  Also note that the lock names are correctly displayed now.

  # perf lock report -c
                  Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns) 
  
         rcu_read_lock     251225          0               0               0               0               0 
    hrtimer_bases.lock      39449          0               0               0               0               0 
   &sb->s_type->i_l...      10301          1             662             662             662             662 
      ptlock_ptr(page)      10173          2             701            1402             760             642 
   &(ei->i_block_re...       8732          0               0               0               0               0 
           &base->lock       6705          0               0               0               0               0 
           &p->pi_lock       5549          0               0               0               0               0 
   &dentry->d_lockr...       5010          4            1274            5097            1844             789 
             &ep->lock       2750          0               0               0               0               0 
   &(__futex_data.q...       2331          0               0               0               0               0 
                (null)       1878          0               0               0               0               0 
      cpu_hotplug_lock       1350          0               0               0               0               0 
      &____s->seqcount       1349          0               0               0               0               0 
      &newf->file_lock       1001         15            1025           15388            2279             618 
  ...

Maybe we can make it default later (with a config and --no-combine-locks).

You can get it from 'perf/lock-combine-v2' branch at

  git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git

Thanks,
Namhyung


Namhyung Kim (6):
  perf lock: Convert lockhash_table to use hlist
  perf lock: Change type of lock_stat->addr to u64
  perf lock: Sort map info based on class name
  perf lock: Fix lock name length check for printing
  perf lock: Add -c/--combine-locks option
  perf lock: Carefully combine lock stats for discarded entries

 tools/perf/Documentation/perf-lock.txt |   4 +
 tools/perf/builtin-lock.c              | 155 +++++++++++++++++++------
 2 files changed, 124 insertions(+), 35 deletions(-)


base-commit: e783362eb54cd99b2cac8b3a9aeac942e6f6ac07
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 1/6] perf lock: Convert lockhash_table to use hlist
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
@ 2022-01-27  0:00 ` Namhyung Kim
  2022-01-27  0:00 ` [PATCH 2/6] perf lock: Change type of lock_stat->addr to u64 Namhyung Kim
                   ` (5 subsequent siblings)
  6 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

The hlist_head has a single entry so we can save some memory.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-lock.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index d70131b7b1b1..43139166f02e 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -38,13 +38,13 @@ static struct perf_session *session;
 #define LOCKHASH_BITS		12
 #define LOCKHASH_SIZE		(1UL << LOCKHASH_BITS)
 
-static struct list_head lockhash_table[LOCKHASH_SIZE];
+static struct hlist_head lockhash_table[LOCKHASH_SIZE];
 
 #define __lockhashfn(key)	hash_long((unsigned long)key, LOCKHASH_BITS)
 #define lockhashentry(key)	(lockhash_table + __lockhashfn((key)))
 
 struct lock_stat {
-	struct list_head	hash_entry;
+	struct hlist_node	hash_entry;
 	struct rb_node		rb;		/* used for sorting */
 
 	/*
@@ -317,10 +317,10 @@ static struct lock_stat *pop_from_result(void)
 
 static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
 {
-	struct list_head *entry = lockhashentry(addr);
+	struct hlist_head *entry = lockhashentry(addr);
 	struct lock_stat *ret, *new;
 
-	list_for_each_entry(ret, entry, hash_entry) {
+	hlist_for_each_entry(ret, entry, hash_entry) {
 		if (ret->addr == addr)
 			return ret;
 	}
@@ -339,7 +339,7 @@ static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
 	strcpy(new->name, name);
 	new->wait_time_min = ULLONG_MAX;
 
-	list_add(&new->hash_entry, entry);
+	hlist_add_head(&new->hash_entry, entry);
 	return new;
 
 alloc_failed:
@@ -781,7 +781,7 @@ static void dump_map(void)
 
 	pr_info("Address of instance: name of class\n");
 	for (i = 0; i < LOCKHASH_SIZE; i++) {
-		list_for_each_entry(st, &lockhash_table[i], hash_entry) {
+		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
 			pr_info(" %p: %s\n", st->addr, st->name);
 		}
 	}
@@ -838,7 +838,7 @@ static void sort_result(void)
 	struct lock_stat *st;
 
 	for (i = 0; i < LOCKHASH_SIZE; i++) {
-		list_for_each_entry(st, &lockhash_table[i], hash_entry) {
+		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
 			insert_to_result(st, compare);
 		}
 	}
@@ -990,7 +990,7 @@ int cmd_lock(int argc, const char **argv)
 	int rc = 0;
 
 	for (i = 0; i < LOCKHASH_SIZE; i++)
-		INIT_LIST_HEAD(lockhash_table + i);
+		INIT_HLIST_HEAD(lockhash_table + i);
 
 	argc = parse_options_subcommand(argc, argv, lock_options, lock_subcommands,
 					lock_usage, PARSE_OPT_STOP_AT_NON_OPTION);
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 2/6] perf lock: Change type of lock_stat->addr to u64
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
  2022-01-27  0:00 ` [PATCH 1/6] perf lock: Convert lockhash_table to use hlist Namhyung Kim
@ 2022-01-27  0:00 ` Namhyung Kim
  2022-01-27  0:00 ` [PATCH 3/6] perf lock: Sort map info based on class name Namhyung Kim
                   ` (4 subsequent siblings)
  6 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

As evsel__intval() returns u64, we can just use it as is.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-lock.c | 35 +++++++++--------------------------
 1 file changed, 9 insertions(+), 26 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 43139166f02e..c4b5c3d71ae3 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -47,12 +47,7 @@ struct lock_stat {
 	struct hlist_node	hash_entry;
 	struct rb_node		rb;		/* used for sorting */
 
-	/*
-	 * FIXME: evsel__intval() returns u64,
-	 * so address of lockdep_map should be treated as 64bit.
-	 * Is there more better solution?
-	 */
-	void			*addr;		/* address of lockdep_map, used as ID */
+	u64			addr;		/* address of lockdep_map, used as ID */
 	char			*name;		/* for strcpy(), we cannot use const */
 
 	unsigned int		nr_acquire;
@@ -106,7 +101,7 @@ struct lock_seq_stat {
 	struct list_head        list;
 	int			state;
 	u64			prev_event_time;
-	void                    *addr;
+	u64                     addr;
 
 	int                     read_count;
 };
@@ -315,7 +310,7 @@ static struct lock_stat *pop_from_result(void)
 	return container_of(node, struct lock_stat, rb);
 }
 
-static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
+static struct lock_stat *lock_stat_findnew(u64 addr, const char *name)
 {
 	struct hlist_head *entry = lockhashentry(addr);
 	struct lock_stat *ret, *new;
@@ -361,7 +356,7 @@ struct trace_lock_handler {
 			     struct perf_sample *sample);
 };
 
-static struct lock_seq_stat *get_seq(struct thread_stat *ts, void *addr)
+static struct lock_seq_stat *get_seq(struct thread_stat *ts, u64 addr)
 {
 	struct lock_seq_stat *seq;
 
@@ -400,16 +395,13 @@ enum acquire_flags {
 static int report_lock_acquire_event(struct evsel *evsel,
 				     struct perf_sample *sample)
 {
-	void *addr;
 	struct lock_stat *ls;
 	struct thread_stat *ts;
 	struct lock_seq_stat *seq;
 	const char *name = evsel__strval(evsel, sample, "name");
-	u64 tmp	 = evsel__intval(evsel, sample, "lockdep_addr");
+	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
 	int flag = evsel__intval(evsel, sample, "flags");
 
-	memcpy(&addr, &tmp, sizeof(void *));
-
 	ls = lock_stat_findnew(addr, name);
 	if (!ls)
 		return -ENOMEM;
@@ -472,15 +464,12 @@ static int report_lock_acquire_event(struct evsel *evsel,
 static int report_lock_acquired_event(struct evsel *evsel,
 				      struct perf_sample *sample)
 {
-	void *addr;
 	struct lock_stat *ls;
 	struct thread_stat *ts;
 	struct lock_seq_stat *seq;
 	u64 contended_term;
 	const char *name = evsel__strval(evsel, sample, "name");
-	u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
-
-	memcpy(&addr, &tmp, sizeof(void *));
+	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
 
 	ls = lock_stat_findnew(addr, name);
 	if (!ls)
@@ -535,14 +524,11 @@ static int report_lock_acquired_event(struct evsel *evsel,
 static int report_lock_contended_event(struct evsel *evsel,
 				       struct perf_sample *sample)
 {
-	void *addr;
 	struct lock_stat *ls;
 	struct thread_stat *ts;
 	struct lock_seq_stat *seq;
 	const char *name = evsel__strval(evsel, sample, "name");
-	u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
-
-	memcpy(&addr, &tmp, sizeof(void *));
+	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
 
 	ls = lock_stat_findnew(addr, name);
 	if (!ls)
@@ -590,14 +576,11 @@ static int report_lock_contended_event(struct evsel *evsel,
 static int report_lock_release_event(struct evsel *evsel,
 				     struct perf_sample *sample)
 {
-	void *addr;
 	struct lock_stat *ls;
 	struct thread_stat *ts;
 	struct lock_seq_stat *seq;
 	const char *name = evsel__strval(evsel, sample, "name");
-	u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
-
-	memcpy(&addr, &tmp, sizeof(void *));
+	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
 
 	ls = lock_stat_findnew(addr, name);
 	if (!ls)
@@ -782,7 +765,7 @@ static void dump_map(void)
 	pr_info("Address of instance: name of class\n");
 	for (i = 0; i < LOCKHASH_SIZE; i++) {
 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
-			pr_info(" %p: %s\n", st->addr, st->name);
+			pr_info(" %#llx: %s\n", (unsigned long long)st->addr, st->name);
 		}
 	}
 }
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 3/6] perf lock: Sort map info based on class name
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
  2022-01-27  0:00 ` [PATCH 1/6] perf lock: Convert lockhash_table to use hlist Namhyung Kim
  2022-01-27  0:00 ` [PATCH 2/6] perf lock: Change type of lock_stat->addr to u64 Namhyung Kim
@ 2022-01-27  0:00 ` Namhyung Kim
  2022-01-27  0:00 ` [PATCH 4/6] perf lock: Fix lock name length check for printing Namhyung Kim
                   ` (3 subsequent siblings)
  6 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

Instead of the random order, sort it by lock class name.

Before:
  # perf lock info -m
  Address of instance: name of class
   0xffffa0d940ac5310: &dentry->d_lockref.lock
   0xffffa0c20b0e1cb0: &dentry->d_lockref.lock
   0xffffa0d8e051cc48: &base->lock
   0xffffa0d94f992110: &anon_vma->rwsem
   0xffffa0d947a4f278: (null)
   0xffffa0c208f6e108: &map->lock
   0xffffa0c213ad32c8: &cfs_rq->removed.lock
   0xffffa0c20d695888: &parent->list_lock
   0xffffa0c278775278: (null)
   0xffffa0c212ad4690: &dentry->d_lockref.lock

After:
  # perf lock info -m
  Address of instance: name of class
   0xffffa0c20d538800: &(&sig->stats_lock)->lock
   0xffffa0c216d4ec40: &(&sig->stats_lock)->lock
   0xffffa1fe4cb04610: &(__futex_data.queues)[i].lock
   0xffffa1fe4cb07750: &(__futex_data.queues)[i].lock
   0xffffa1fe4cb07b50: &(__futex_data.queues)[i].lock
   0xffffa1fe4cb0b850: &(__futex_data.queues)[i].lock
   0xffffa1fe4cb0bcd0: &(__futex_data.queues)[i].lock
   0xffffa1fe4cb0e5d0: &(__futex_data.queues)[i].lock
   0xffffa1fe4cb11ad0: &(__futex_data.queues)[i].lock

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-lock.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index c4b5c3d71ae3..8078f7ca826d 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -757,6 +757,21 @@ static void dump_threads(void)
 	}
 }
 
+static int compare_maps(struct lock_stat *a, struct lock_stat *b)
+{
+	int ret;
+
+	if (a->name && b->name)
+		ret = strcmp(a->name, b->name);
+	else
+		ret = !!a->name - !!b->name;
+
+	if (!ret)
+		return a->addr < b->addr;
+	else
+		return ret < 0;
+}
+
 static void dump_map(void)
 {
 	unsigned int i;
@@ -765,9 +780,12 @@ static void dump_map(void)
 	pr_info("Address of instance: name of class\n");
 	for (i = 0; i < LOCKHASH_SIZE; i++) {
 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
-			pr_info(" %#llx: %s\n", (unsigned long long)st->addr, st->name);
+			insert_to_result(st, compare_maps);
 		}
 	}
+
+	while ((st = pop_from_result()))
+		pr_info(" %#llx: %s\n", (unsigned long long)st->addr, st->name);
 }
 
 static int dump_info(void)
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 4/6] perf lock: Fix lock name length check for printing
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
                   ` (2 preceding siblings ...)
  2022-01-27  0:00 ` [PATCH 3/6] perf lock: Sort map info based on class name Namhyung Kim
@ 2022-01-27  0:00 ` Namhyung Kim
  2022-01-27  0:00 ` [PATCH 5/6] perf lock: Add -c/--combine-locks option Namhyung Kim
                   ` (2 subsequent siblings)
  6 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

It has 20 character spaces for name so lock names shorter than 20
should be printed without ellipsis.

Before:
 # perf lock report
                Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns)

       rcu_read_lock     251225          0               0               0               0               0
 &(ei->i_block_re...       8731          0               0               0               0               0
 &sb->s_type->i_l...       8731          0               0               0               0               0
 hrtimer_bases.lo...       5261          0               0               0               0               0
 hrtimer_bases.lo...       2626          0               0               0               0               0
 hrtimer_bases.lo...       1953          0               0               0               0               0
 hrtimer_bases.lo...       1382          0               0               0               0               0
 cpu_hotplug_lock...       1350          0               0               0               0               0

After:
 # perf lock report
                Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns)

       rcu_read_lock     251225          0               0               0               0               0
 &(ei->i_block_re...       8731          0               0               0               0               0
 &sb->s_type->i_l...       8731          0               0               0               0               0
  hrtimer_bases.lock       5261          0               0               0               0               0
  hrtimer_bases.lock       2626          0               0               0               0               0
  hrtimer_bases.lock       1953          0               0               0               0               0
  hrtimer_bases.lock       1382          0               0               0               0               0
    cpu_hotplug_lock       1350          0               0               0               0               0

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-lock.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 8078f7ca826d..f6adf3cdd1e2 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -710,7 +710,7 @@ static void print_result(void)
 		}
 		bzero(cut_name, 20);
 
-		if (strlen(st->name) < 16) {
+		if (strlen(st->name) < 20) {
 			/* output raw name */
 			pr_info("%20s ", st->name);
 		} else {
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 5/6] perf lock: Add -c/--combine-locks option
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
                   ` (3 preceding siblings ...)
  2022-01-27  0:00 ` [PATCH 4/6] perf lock: Fix lock name length check for printing Namhyung Kim
@ 2022-01-27  0:00 ` Namhyung Kim
  2022-01-27  0:00 ` [PATCH 6/6] perf lock: Carefully combine lock stats for discarded entries Namhyung Kim
  2022-02-10 18:45 ` [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Arnaldo Carvalho de Melo
  6 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

The -c or --combine-locks option is to merge lock instances in the
same class into a single entry.  It compares the name of the locks
and marks duplicated entries using lock_stat->combined.

 # perf lock report
                Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns)

       rcu_read_lock     251225          0               0               0               0               0
 &(ei->i_block_re...       8731          0               0               0               0               0
 &sb->s_type->i_l...       8731          0               0               0               0               0
  hrtimer_bases.lock       5261          0               0               0               0               0
  hrtimer_bases.lock       2626          0               0               0               0               0
  hrtimer_bases.lock       1953          0               0               0               0               0
  hrtimer_bases.lock       1382          0               0               0               0               0
    cpu_hotplug_lock       1350          0               0               0               0               0
  hrtimer_bases.lock       1273          0               0               0               0               0
  hrtimer_bases.lock       1269          0               0               0               0               0

 # perf lock report -c
                Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns)

       rcu_read_lock     251225          0               0               0               0               0
  hrtimer_bases.lock      39450          0               0               0               0               0
 &sb->s_type->i_l...      10301          1             662             662             662             662
    ptlock_ptr(page)      10173          2             701            1402             760             642
 &(ei->i_block_re...       8732          0               0               0               0               0
        &xa->xa_lock       8088          0               0               0               0               0
         &base->lock       6705          0               0               0               0               0
         &p->pi_lock       5549          0               0               0               0               0
 &dentry->d_lockr...       5010          4            1274            5097            1844             789
           &ep->lock       3958          0               0               0               0               0

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/Documentation/perf-lock.txt |  4 ++
 tools/perf/builtin-lock.c              | 68 ++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt
index 1b4d452923d7..f5eb95788969 100644
--- a/tools/perf/Documentation/perf-lock.txt
+++ b/tools/perf/Documentation/perf-lock.txt
@@ -54,6 +54,10 @@ REPORT OPTIONS
         Sorting key. Possible values: acquired (default), contended,
 	avg_wait, wait_total, wait_max, wait_min.
 
+-c::
+--combine-locks::
+	Merge lock instances in the same class (based on name).
+
 INFO OPTIONS
 ------------
 
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index f6adf3cdd1e2..bbfeba79426a 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -65,6 +65,7 @@ struct lock_stat {
 	u64			wait_time_max;
 
 	int			discard; /* flag of blacklist */
+	int			combined;
 };
 
 /*
@@ -115,6 +116,8 @@ struct thread_stat {
 
 static struct rb_root		thread_stats;
 
+static bool combine_locks;
+
 static struct thread_stat *thread_stat_find(u32 tid)
 {
 	struct rb_node *node;
@@ -241,6 +244,7 @@ static const char		*sort_key = "acquired";
 
 static int			(*compare)(struct lock_stat *, struct lock_stat *);
 
+static struct rb_root		sorted; /* place to store intermediate data */
 static struct rb_root		result;	/* place to store sorted data */
 
 #define DEF_KEY_LOCK(name, fn_suffix)	\
@@ -274,6 +278,49 @@ static int select_key(void)
 	return -1;
 }
 
+static void combine_lock_stats(struct lock_stat *st)
+{
+	struct rb_node **rb = &sorted.rb_node;
+	struct rb_node *parent = NULL;
+	struct lock_stat *p;
+	int ret;
+
+	while (*rb) {
+		p = container_of(*rb, struct lock_stat, rb);
+		parent = *rb;
+
+		if (st->name && p->name)
+			ret = strcmp(st->name, p->name);
+		else
+			ret = !!st->name - !!p->name;
+
+		if (ret == 0) {
+			p->nr_acquired += st->nr_acquired;
+			p->nr_contended += st->nr_contended;
+			p->wait_time_total += st->wait_time_total;
+
+			if (p->nr_contended)
+				p->avg_wait_time = p->wait_time_total / p->nr_contended;
+
+			if (p->wait_time_min > st->wait_time_min)
+				p->wait_time_min = st->wait_time_min;
+			if (p->wait_time_max < st->wait_time_max)
+				p->wait_time_max = st->wait_time_max;
+
+			st->combined = 1;
+			return;
+		}
+
+		if (ret < 0)
+			rb = &(*rb)->rb_left;
+		else
+			rb = &(*rb)->rb_right;
+	}
+
+	rb_link_node(&st->rb, parent, rb);
+	rb_insert_color(&st->rb, &sorted);
+}
+
 static void insert_to_result(struct lock_stat *st,
 			     int (*bigger)(struct lock_stat *, struct lock_stat *))
 {
@@ -281,6 +328,9 @@ static void insert_to_result(struct lock_stat *st,
 	struct rb_node *parent = NULL;
 	struct lock_stat *p;
 
+	if (combine_locks && st->combined)
+		return;
+
 	while (*rb) {
 		p = container_of(*rb, struct lock_stat, rb);
 		parent = *rb;
@@ -833,6 +883,21 @@ static int process_sample_event(struct perf_tool *tool __maybe_unused,
 	return err;
 }
 
+static void combine_result(void)
+{
+	unsigned int i;
+	struct lock_stat *st;
+
+	if (!combine_locks)
+		return;
+
+	for (i = 0; i < LOCKHASH_SIZE; i++) {
+		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
+			combine_lock_stats(st);
+		}
+	}
+}
+
 static void sort_result(void)
 {
 	unsigned int i;
@@ -896,6 +961,7 @@ static int __cmd_report(bool display_info)
 	if (display_info) /* used for info subcommand */
 		err = dump_info();
 	else {
+		combine_result();
 		sort_result();
 		print_result();
 	}
@@ -970,6 +1036,8 @@ int cmd_lock(int argc, const char **argv)
 	OPT_STRING('k', "key", &sort_key, "acquired",
 		    "key for sorting (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
 	/* TODO: type */
+	OPT_BOOLEAN('c', "combine-locks", &combine_locks,
+		    "combine locks in the same class"),
 	OPT_PARENT(lock_options)
 	};
 
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 6/6] perf lock: Carefully combine lock stats for discarded entries
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
                   ` (4 preceding siblings ...)
  2022-01-27  0:00 ` [PATCH 5/6] perf lock: Add -c/--combine-locks option Namhyung Kim
@ 2022-01-27  0:00 ` Namhyung Kim
  2022-02-10 18:45 ` [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Arnaldo Carvalho de Melo
  6 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-27  0:00 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

Stats from discarded entries should be omitted.  But a lock class may
have both good and bad entries.  If the first entry was bad, we can
zero-fill the stats and only add good stats if any.  The entry can
remove the discard state if it finds a good entry later.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-lock.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index bbfeba79426a..57b9ebd7118a 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -295,6 +295,9 @@ static void combine_lock_stats(struct lock_stat *st)
 			ret = !!st->name - !!p->name;
 
 		if (ret == 0) {
+			if (st->discard)
+				goto out;
+
 			p->nr_acquired += st->nr_acquired;
 			p->nr_contended += st->nr_contended;
 			p->wait_time_total += st->wait_time_total;
@@ -307,6 +310,10 @@ static void combine_lock_stats(struct lock_stat *st)
 			if (p->wait_time_max < st->wait_time_max)
 				p->wait_time_max = st->wait_time_max;
 
+			/* now it got a new !discard record */
+			p->discard = 0;
+
+out:
 			st->combined = 1;
 			return;
 		}
@@ -319,6 +326,15 @@ static void combine_lock_stats(struct lock_stat *st)
 
 	rb_link_node(&st->rb, parent, rb);
 	rb_insert_color(&st->rb, &sorted);
+
+	if (st->discard) {
+		st->nr_acquired = 0;
+		st->nr_contended = 0;
+		st->wait_time_total = 0;
+		st->avg_wait_time = 0;
+		st->wait_time_min = ULLONG_MAX;
+		st->wait_time_max = 0;
+	}
 }
 
 static void insert_to_result(struct lock_stat *st,
-- 
2.35.0.rc0.227.g00780c9af4-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2)
  2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
                   ` (5 preceding siblings ...)
  2022-01-27  0:00 ` [PATCH 6/6] perf lock: Carefully combine lock stats for discarded entries Namhyung Kim
@ 2022-02-10 18:45 ` Arnaldo Carvalho de Melo
  6 siblings, 0 replies; 9+ messages in thread
From: Arnaldo Carvalho de Melo @ 2022-02-10 18:45 UTC (permalink / raw)
  To: Namhyung Kim
  Cc: Jiri Olsa, Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

Em Wed, Jan 26, 2022 at 04:00:44PM -0800, Namhyung Kim escreveu:
> Hello,
> 
> I have some updates in the perf lock command (focused on 'report').
> The main change is to add -c (or --combine-locks) option to aggregate
> results based on lock class name.
> 
>  * changes from v1)
>   - rebased onto recent acme/perf/core
>   - add Jiri's Acked-by

Thanks, applied.

- Arnaldo

 
> Without this option, the result deals with lock addresses so instances
> in the same lock class will have separate entries like below:
> 
>   # perf lock report
>                   Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns) 
> 
>          rcu_read_lock     251225          0               0               0               0               0 
>    &(ei->i_block_re...       8731          0               0               0               0               0 
>    &sb->s_type->i_l...       8731          0               0               0               0               0 
>    hrtimer_bases.lo...       5261          0               0               0               0               0 
>    hrtimer_bases.lo...       2626          0               0               0               0               0 
>    hrtimer_bases.lo...       1953          0               0               0               0               0 
>    hrtimer_bases.lo...       1382          0               0               0               0               0 
>    cpu_hotplug_lock...       1350          0               0               0               0               0 
>    hrtimer_bases.lo...       1273          0               0               0               0               0 
>    hrtimer_bases.lo...       1269          0               0               0               0               0 
>    hrtimer_bases.lo...       1198          0               0               0               0               0 
>    hrtimer_bases.lo...       1116          0               0               0               0               0 
>            &base->lock       1109          0               0               0               0               0 
>    hrtimer_bases.lo...       1067          0               0               0               0               0 
>    hrtimer_bases.lo...       1052          0               0               0               0               0 
>    hrtimer_bases.lo...        957          0               0               0               0               0 
>    hrtimer_bases.lo...        948          0               0               0               0               0 
>           css_set_lock        791          0               0               0               0               0 
>    hrtimer_bases.lo...        752          0               0               0               0               0 
>    &lruvec->lru_loc...        747          5           11254           56272           18317            1412 
>    hrtimer_bases.lo...        738          0               0               0               0               0 
>    &newf->file_lock...        706         15            1025           15388            2279             618 
>    hrtimer_bases.lo...        702          0               0               0               0               0 
>    hrtimer_bases.lo...        694          0               0               0               0               0 
>   ...
> 
> With -c option, the hrtimer_bases.lock would be combined into a single
> entry.  Also note that the lock names are correctly displayed now.
> 
>   # perf lock report -c
>                   Name   acquired  contended   avg wait (ns) total wait (ns)   max wait (ns)   min wait (ns) 
>   
>          rcu_read_lock     251225          0               0               0               0               0 
>     hrtimer_bases.lock      39449          0               0               0               0               0 
>    &sb->s_type->i_l...      10301          1             662             662             662             662 
>       ptlock_ptr(page)      10173          2             701            1402             760             642 
>    &(ei->i_block_re...       8732          0               0               0               0               0 
>            &base->lock       6705          0               0               0               0               0 
>            &p->pi_lock       5549          0               0               0               0               0 
>    &dentry->d_lockr...       5010          4            1274            5097            1844             789 
>              &ep->lock       2750          0               0               0               0               0 
>    &(__futex_data.q...       2331          0               0               0               0               0 
>                 (null)       1878          0               0               0               0               0 
>       cpu_hotplug_lock       1350          0               0               0               0               0 
>       &____s->seqcount       1349          0               0               0               0               0 
>       &newf->file_lock       1001         15            1025           15388            2279             618 
>   ...
> 
> Maybe we can make it default later (with a config and --no-combine-locks).
> 
> You can get it from 'perf/lock-combine-v2' branch at
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
> 
> Thanks,
> Namhyung
> 
> 
> Namhyung Kim (6):
>   perf lock: Convert lockhash_table to use hlist
>   perf lock: Change type of lock_stat->addr to u64
>   perf lock: Sort map info based on class name
>   perf lock: Fix lock name length check for printing
>   perf lock: Add -c/--combine-locks option
>   perf lock: Carefully combine lock stats for discarded entries
> 
>  tools/perf/Documentation/perf-lock.txt |   4 +
>  tools/perf/builtin-lock.c              | 155 +++++++++++++++++++------
>  2 files changed, 124 insertions(+), 35 deletions(-)
> 
> 
> base-commit: e783362eb54cd99b2cac8b3a9aeac942e6f6ac07
> -- 
> 2.35.0.rc0.227.g00780c9af4-goog

-- 

- Arnaldo

^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 1/6] perf lock: Convert lockhash_table to use hlist
  2022-01-04 18:20 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v1) Namhyung Kim
@ 2022-01-04 18:20 ` Namhyung Kim
  0 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2022-01-04 18:20 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, LKML, Andi Kleen, Ian Rogers

The hlist_head has a single entry so we can save some memory.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-lock.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index d70131b7b1b1..43139166f02e 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -38,13 +38,13 @@ static struct perf_session *session;
 #define LOCKHASH_BITS		12
 #define LOCKHASH_SIZE		(1UL << LOCKHASH_BITS)
 
-static struct list_head lockhash_table[LOCKHASH_SIZE];
+static struct hlist_head lockhash_table[LOCKHASH_SIZE];
 
 #define __lockhashfn(key)	hash_long((unsigned long)key, LOCKHASH_BITS)
 #define lockhashentry(key)	(lockhash_table + __lockhashfn((key)))
 
 struct lock_stat {
-	struct list_head	hash_entry;
+	struct hlist_node	hash_entry;
 	struct rb_node		rb;		/* used for sorting */
 
 	/*
@@ -317,10 +317,10 @@ static struct lock_stat *pop_from_result(void)
 
 static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
 {
-	struct list_head *entry = lockhashentry(addr);
+	struct hlist_head *entry = lockhashentry(addr);
 	struct lock_stat *ret, *new;
 
-	list_for_each_entry(ret, entry, hash_entry) {
+	hlist_for_each_entry(ret, entry, hash_entry) {
 		if (ret->addr == addr)
 			return ret;
 	}
@@ -339,7 +339,7 @@ static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
 	strcpy(new->name, name);
 	new->wait_time_min = ULLONG_MAX;
 
-	list_add(&new->hash_entry, entry);
+	hlist_add_head(&new->hash_entry, entry);
 	return new;
 
 alloc_failed:
@@ -781,7 +781,7 @@ static void dump_map(void)
 
 	pr_info("Address of instance: name of class\n");
 	for (i = 0; i < LOCKHASH_SIZE; i++) {
-		list_for_each_entry(st, &lockhash_table[i], hash_entry) {
+		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
 			pr_info(" %p: %s\n", st->addr, st->name);
 		}
 	}
@@ -838,7 +838,7 @@ static void sort_result(void)
 	struct lock_stat *st;
 
 	for (i = 0; i < LOCKHASH_SIZE; i++) {
-		list_for_each_entry(st, &lockhash_table[i], hash_entry) {
+		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
 			insert_to_result(st, compare);
 		}
 	}
@@ -990,7 +990,7 @@ int cmd_lock(int argc, const char **argv)
 	int rc = 0;
 
 	for (i = 0; i < LOCKHASH_SIZE; i++)
-		INIT_LIST_HEAD(lockhash_table + i);
+		INIT_HLIST_HEAD(lockhash_table + i);
 
 	argc = parse_options_subcommand(argc, argv, lock_options, lock_subcommands,
 					lock_usage, PARSE_OPT_STOP_AT_NON_OPTION);
-- 
2.34.1.448.ga2b2bfdf31-goog


^ permalink raw reply related	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2022-02-10 18:45 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-01-27  0:00 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Namhyung Kim
2022-01-27  0:00 ` [PATCH 1/6] perf lock: Convert lockhash_table to use hlist Namhyung Kim
2022-01-27  0:00 ` [PATCH 2/6] perf lock: Change type of lock_stat->addr to u64 Namhyung Kim
2022-01-27  0:00 ` [PATCH 3/6] perf lock: Sort map info based on class name Namhyung Kim
2022-01-27  0:00 ` [PATCH 4/6] perf lock: Fix lock name length check for printing Namhyung Kim
2022-01-27  0:00 ` [PATCH 5/6] perf lock: Add -c/--combine-locks option Namhyung Kim
2022-01-27  0:00 ` [PATCH 6/6] perf lock: Carefully combine lock stats for discarded entries Namhyung Kim
2022-02-10 18:45 ` [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v2) Arnaldo Carvalho de Melo
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2022-01-04 18:20 [PATCHSET 0/6] perf lock: Random updates for the locking analysis (v1) Namhyung Kim
2022-01-04 18:20 ` [PATCH 1/6] perf lock: Convert lockhash_table to use hlist Namhyung Kim

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