adulau/aha
1
0
Fork 0
mirror of https://github.com/adulau/aha.git synced 2024-12-28 03:36:19 +00:00
Code Issues Projects Releases Packages Wiki Activity

lockstat: contend with points

Browse source 
We currently only provide points that have to wait on contention, also
lists the points we have to wait for.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2008-10-16 23:17:09 +02:00 committed by Ingo Molnar
parent 7317d7b87e
commit c7e78cff6b
5 changed files with 82 additions and 37 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

50
Documentation/lockstat.txt
View file

@ -71,34 +71,48 @@ Look at the current lock statistics:
# less /proc/lock_stat # less /proc/lock_stat
01 lock_stat version 0.2 01 lock_stat version 0.3
02 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 02 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
03 class name con-bounces contentions waittime-min waittime-max waittime-total acq-bounces acquisitions holdtime-min holdtime-max holdtime-total 03 class name con-bounces contentions waittime-min waittime-max waittime-total acq-bounces acquisitions holdtime-min holdtime-max holdtime-total
04 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 04 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
05 05
06 &inode->i_data.tree_lock-W: 15 21657 0.18 1093295.30 11547131054.85 58 10415 0.16 87.51 6387.60 06 &mm->mmap_sem-W: 233 538 18446744073708 22924.27 607243.51 1342 45806 1.71 8595.89 1180582.34
07 &inode->i_data.tree_lock-R: 0 0 0.00 0.00 0.00 23302 231198 0.25 8.45 98023.38 07 &mm->mmap_sem-R: 205 587 18446744073708 28403.36 731975.00 1940 412426 0.58 187825.45 6307502.88
08 -------------------------- 08 ---------------
09 &inode->i_data.tree_lock 0 [<ffffffff8027c08f>] add_to_page_cache+0x5f/0x190 09 &mm->mmap_sem 487 [<ffffffff8053491f>] do_page_fault+0x466/0x928
10 10 &mm->mmap_sem 179 [<ffffffff802a6200>] sys_mprotect+0xcd/0x21d
11 ............................................................................................................................................................................................... 11 &mm->mmap_sem 279 [<ffffffff80210a57>] sys_mmap+0x75/0xce
12 12 &mm->mmap_sem 76 [<ffffffff802a490b>] sys_munmap+0x32/0x59
13 dcache_lock: 1037 1161 0.38 45.32 774.51 6611 243371 0.15 306.48 77387.24 13 ---------------
14 ----------- 14 &mm->mmap_sem 270 [<ffffffff80210a57>] sys_mmap+0x75/0xce
15 dcache_lock 180 [<ffffffff802c0d7e>] sys_getcwd+0x11e/0x230 15 &mm->mmap_sem 431 [<ffffffff8053491f>] do_page_fault+0x466/0x928
16 dcache_lock 165 [<ffffffff802c002a>] d_alloc+0x15a/0x210 16 &mm->mmap_sem 138 [<ffffffff802a490b>] sys_munmap+0x32/0x59
17 dcache_lock 33 [<ffffffff8035818d>] _atomic_dec_and_lock+0x4d/0x70 17 &mm->mmap_sem 145 [<ffffffff802a6200>] sys_mprotect+0xcd/0x21d
18 dcache_lock 1 [<ffffffff802beef8>] shrink_dcache_parent+0x18/0x130 18
19 ...............................................................................................................................................................................................
20
21 dcache_lock: 621 623 0.52 118.26 1053.02 6745 91930 0.29 316.29 118423.41
22 -----------
23 dcache_lock 179 [<ffffffff80378274>] _atomic_dec_and_lock+0x34/0x54
24 dcache_lock 113 [<ffffffff802cc17b>] d_alloc+0x19a/0x1eb
25 dcache_lock 99 [<ffffffff802ca0dc>] d_rehash+0x1b/0x44
26 dcache_lock 104 [<ffffffff802cbca0>] d_instantiate+0x36/0x8a
27 -----------
28 dcache_lock 192 [<ffffffff80378274>] _atomic_dec_and_lock+0x34/0x54
29 dcache_lock 98 [<ffffffff802ca0dc>] d_rehash+0x1b/0x44
30 dcache_lock 72 [<ffffffff802cc17b>] d_alloc+0x19a/0x1eb
31 dcache_lock 112 [<ffffffff802cbca0>] d_instantiate+0x36/0x8a
This excerpt shows the first two lock class statistics. Line 01 shows the This excerpt shows the first two lock class statistics. Line 01 shows the
output version - each time the format changes this will be updated. Line 02-04 output version - each time the format changes this will be updated. Line 02-04
show the header with column descriptions. Lines 05-10 and 13-18 show the actual show the header with column descriptions. Lines 05-18 and 20-31 show the actual
statistics. These statistics come in two parts; the actual stats separated by a statistics. These statistics come in two parts; the actual stats separated by a
short separator (line 08, 14) from the contention points. short separator (line 08, 13) from the contention points.
The first lock (05-10) is a read/write lock, and shows two lines above the The first lock (05-18) is a read/write lock, and shows two lines above the
short separator. The contention points don't match the column descriptors, short separator. The contention points don't match the column descriptors,
they have two: contentions and [<IP>] symbol. they have two: contentions and [<IP>] symbol. The second set of contention
points are the points we're contending with.
The integer part of the time values is in us. The integer part of the time values is in us.

13
include/linux/lockdep.h
View file

@ -73,6 +73,8 @@ struct lock_class_key {
struct lockdep_subclass_key subkeys[MAX_LOCKDEP_SUBCLASSES]; struct lockdep_subclass_key subkeys[MAX_LOCKDEP_SUBCLASSES];
}; };
#define LOCKSTAT_POINTS 4
/* /*
* The lock-class itself: * The lock-class itself:
*/ */
@ -119,7 +121,8 @@ struct lock_class {
int name_version; int name_version;
#ifdef CONFIG_LOCK_STAT #ifdef CONFIG_LOCK_STAT
unsigned long contention_point[4]; unsigned long contention_point[LOCKSTAT_POINTS];
unsigned long contending_point[LOCKSTAT_POINTS];
#endif #endif
}; };
@ -144,6 +147,7 @@ enum bounce_type {
struct lock_class_stats { struct lock_class_stats {
unsigned long contention_point[4]; unsigned long contention_point[4];
unsigned long contending_point[4];
struct lock_time read_waittime; struct lock_time read_waittime;
struct lock_time write_waittime; struct lock_time write_waittime;
struct lock_time read_holdtime; struct lock_time read_holdtime;
@ -165,6 +169,7 @@ struct lockdep_map {
const char *name; const char *name;
#ifdef CONFIG_LOCK_STAT #ifdef CONFIG_LOCK_STAT
int cpu; int cpu;
unsigned long ip;
#endif #endif
}; };
@ -355,7 +360,7 @@ struct lock_class_key { };
#ifdef CONFIG_LOCK_STAT #ifdef CONFIG_LOCK_STAT
extern void lock_contended(struct lockdep_map *lock, unsigned long ip); extern void lock_contended(struct lockdep_map *lock, unsigned long ip);
extern void lock_acquired(struct lockdep_map *lock); extern void lock_acquired(struct lockdep_map *lock, unsigned long ip);
#define LOCK_CONTENDED(_lock, try, lock) \ #define LOCK_CONTENDED(_lock, try, lock) \
do { \ do { \
@ -363,13 +368,13 @@ do { \
lock_contended(&(_lock)->dep_map, _RET_IP_); \ lock_contended(&(_lock)->dep_map, _RET_IP_); \
lock(_lock); \ lock(_lock); \
} \ } \
lock_acquired(&(_lock)->dep_map); \ lock_acquired(&(_lock)->dep_map, _RET_IP_); \
} while (0) } while (0)
#else /* CONFIG_LOCK_STAT */ #else /* CONFIG_LOCK_STAT */
#define lock_contended(lockdep_map, ip) do {} while (0) #define lock_contended(lockdep_map, ip) do {} while (0)
#define lock_acquired(lockdep_map) do {} while (0) #define lock_acquired(lockdep_map, ip) do {} while (0)
#define LOCK_CONTENDED(_lock, try, lock) \ #define LOCK_CONTENDED(_lock, try, lock) \
lock(_lock) lock(_lock)

33
kernel/lockdep.c
View file

@ -136,16 +136,16 @@ static inline struct lock_class *hlock_class(struct held_lock *hlock)
#ifdef CONFIG_LOCK_STAT #ifdef CONFIG_LOCK_STAT
static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats); static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats);
static int lock_contention_point(struct lock_class *class, unsigned long ip) static int lock_point(unsigned long points[], unsigned long ip)
{ {
int i; int i;
for (i = 0; i < ARRAY_SIZE(class->contention_point); i++) { for (i = 0; i < LOCKSTAT_POINTS; i++) {
if (class->contention_point[i] == 0) { if (points[i] == 0) {
class->contention_point[i] = ip; points[i] = ip;
break; break;
} }
if (class->contention_point[i] == ip) if (points[i] == ip)
break; break;
} }
@ -185,6 +185,9 @@ struct lock_class_stats lock_stats(struct lock_class *class)
for (i = 0; i < ARRAY_SIZE(stats.contention_point); i++) for (i = 0; i < ARRAY_SIZE(stats.contention_point); i++)
stats.contention_point[i] += pcs->contention_point[i]; stats.contention_point[i] += pcs->contention_point[i];
for (i = 0; i < ARRAY_SIZE(stats.contending_point); i++)
stats.contending_point[i] += pcs->contending_point[i];
lock_time_add(&pcs->read_waittime, &stats.read_waittime); lock_time_add(&pcs->read_waittime, &stats.read_waittime);
lock_time_add(&pcs->write_waittime, &stats.write_waittime); lock_time_add(&pcs->write_waittime, &stats.write_waittime);
@ -209,6 +212,7 @@ void clear_lock_stats(struct lock_class *class)
memset(cpu_stats, 0, sizeof(struct lock_class_stats)); memset(cpu_stats, 0, sizeof(struct lock_class_stats));
} }
memset(class->contention_point, 0, sizeof(class->contention_point)); memset(class->contention_point, 0, sizeof(class->contention_point));
memset(class->contending_point, 0, sizeof(class->contending_point));
} }
static struct lock_class_stats *get_lock_stats(struct lock_class *class) static struct lock_class_stats *get_lock_stats(struct lock_class *class)
@ -3001,7 +3005,7 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
struct held_lock *hlock, *prev_hlock; struct held_lock *hlock, *prev_hlock;
struct lock_class_stats *stats; struct lock_class_stats *stats;
unsigned int depth; unsigned int depth;
int i, point; int i, contention_point, contending_point;
depth = curr->lockdep_depth; depth = curr->lockdep_depth;
if (DEBUG_LOCKS_WARN_ON(!depth)) if (DEBUG_LOCKS_WARN_ON(!depth))
@ -3025,18 +3029,22 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
found_it: found_it:
hlock->waittime_stamp = sched_clock(); hlock->waittime_stamp = sched_clock();
point = lock_contention_point(hlock_class(hlock), ip); contention_point = lock_point(hlock_class(hlock)->contention_point, ip);
contending_point = lock_point(hlock_class(hlock)->contending_point,
lock->ip);
stats = get_lock_stats(hlock_class(hlock)); stats = get_lock_stats(hlock_class(hlock));
if (point < ARRAY_SIZE(stats->contention_point)) if (contention_point < LOCKSTAT_POINTS)
stats->contention_point[point]++; stats->contention_point[contention_point]++;
if (contending_point < LOCKSTAT_POINTS)
stats->contending_point[contending_point]++;
if (lock->cpu != smp_processor_id()) if (lock->cpu != smp_processor_id())
stats->bounces[bounce_contended + !!hlock->read]++; stats->bounces[bounce_contended + !!hlock->read]++;
put_lock_stats(stats); put_lock_stats(stats);
} }
static void static void
__lock_acquired(struct lockdep_map *lock) __lock_acquired(struct lockdep_map *lock, unsigned long ip)
{ {
struct task_struct *curr = current; struct task_struct *curr = current;
struct held_lock *hlock, *prev_hlock; struct held_lock *hlock, *prev_hlock;
@ -3085,6 +3093,7 @@ found_it:
put_lock_stats(stats); put_lock_stats(stats);
lock->cpu = cpu; lock->cpu = cpu;
lock->ip = ip;
} }
void lock_contended(struct lockdep_map *lock, unsigned long ip) void lock_contended(struct lockdep_map *lock, unsigned long ip)
@ -3106,7 +3115,7 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip)
} }
EXPORT_SYMBOL_GPL(lock_contended); EXPORT_SYMBOL_GPL(lock_contended);
void lock_acquired(struct lockdep_map *lock) void lock_acquired(struct lockdep_map *lock, unsigned long ip)
{ {
unsigned long flags; unsigned long flags;
@ -3119,7 +3128,7 @@ void lock_acquired(struct lockdep_map *lock)
raw_local_irq_save(flags); raw_local_irq_save(flags);
check_flags(flags); check_flags(flags);
current->lockdep_recursion = 1; current->lockdep_recursion = 1;
__lock_acquired(lock); __lock_acquired(lock, ip);
current->lockdep_recursion = 0; current->lockdep_recursion = 0;
raw_local_irq_restore(flags); raw_local_irq_restore(flags);
} }

21
kernel/lockdep_proc.c
View file

@ -557,7 +557,7 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
if (stats->read_holdtime.nr) if (stats->read_holdtime.nr)
namelen += 2; namelen += 2;
for (i = 0; i < ARRAY_SIZE(class->contention_point); i++) { for (i = 0; i < LOCKSTAT_POINTS; i++) {
char sym[KSYM_SYMBOL_LEN]; char sym[KSYM_SYMBOL_LEN];
char ip[32]; char ip[32];
@ -574,6 +574,23 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
stats->contention_point[i], stats->contention_point[i],
ip, sym); ip, sym);
} }
for (i = 0; i < LOCKSTAT_POINTS; i++) {
char sym[KSYM_SYMBOL_LEN];
char ip[32];
if (class->contending_point[i] == 0)
break;
if (!i)
seq_line(m, '-', 40-namelen, namelen);
sprint_symbol(sym, class->contending_point[i]);
snprintf(ip, sizeof(ip), "[<%p>]",
(void *)class->contending_point[i]);
seq_printf(m, "%40s %14lu %29s %s\n", name,
stats->contending_point[i],
ip, sym);
}
if (i) { if (i) {
seq_puts(m, "\n"); seq_puts(m, "\n");
seq_line(m, '.', 0, 40 + 1 + 10 * (14 + 1)); seq_line(m, '.', 0, 40 + 1 + 10 * (14 + 1));
@ -583,7 +600,7 @@ static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
static void seq_header(struct seq_file *m) static void seq_header(struct seq_file *m)
{ {
seq_printf(m, "lock_stat version 0.2\n"); seq_printf(m, "lock_stat version 0.3\n");
seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1)); seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s " seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s "
"%14s %14s\n", "%14s %14s\n",

2
kernel/mutex.c
View file

@ -184,7 +184,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
} }
done: done:
lock_acquired(&lock->dep_map); lock_acquired(&lock->dep_map, ip);
/* got the lock - rejoice! */ /* got the lock - rejoice! */
mutex_remove_waiter(lock, &waiter, task_thread_info(task)); mutex_remove_waiter(lock, &waiter, task_thread_info(task));
debug_mutex_set_owner(lock, task_thread_info(task)); debug_mutex_set_owner(lock, task_thread_info(task));