lockstat: contend with points

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

View File

@@ -136,16 +136,16 @@ static inline struct lock_class *hlock_class(struct held_lock *hlock)
#ifdef CONFIG_LOCK_STAT
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;
for (i = 0; i < ARRAY_SIZE(class->contention_point); i++) {
if (class->contention_point[i] == 0) {
class->contention_point[i] = ip;
for (i = 0; i < LOCKSTAT_POINTS; i++) {
if (points[i] == 0) {
points[i] = ip;
break;
}
if (class->contention_point[i] == ip)
if (points[i] == ip)
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++)
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->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(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)
@@ -3001,7 +3005,7 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
struct held_lock *hlock, *prev_hlock;
struct lock_class_stats *stats;
unsigned int depth;
int i, point;
int i, contention_point, contending_point;
depth = curr->lockdep_depth;
if (DEBUG_LOCKS_WARN_ON(!depth))
@@ -3025,18 +3029,22 @@ __lock_contended(struct lockdep_map *lock, unsigned long ip)
found_it:
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));
if (point < ARRAY_SIZE(stats->contention_point))
stats->contention_point[point]++;
if (contention_point < LOCKSTAT_POINTS)
stats->contention_point[contention_point]++;
if (contending_point < LOCKSTAT_POINTS)
stats->contending_point[contending_point]++;
if (lock->cpu != smp_processor_id())
stats->bounces[bounce_contended + !!hlock->read]++;
put_lock_stats(stats);
}
static void
__lock_acquired(struct lockdep_map *lock)
__lock_acquired(struct lockdep_map *lock, unsigned long ip)
{
struct task_struct *curr = current;
struct held_lock *hlock, *prev_hlock;
@@ -3085,6 +3093,7 @@ found_it:
put_lock_stats(stats);
lock->cpu = cpu;
lock->ip = 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);
void lock_acquired(struct lockdep_map *lock)
void lock_acquired(struct lockdep_map *lock, unsigned long ip)
{
unsigned long flags;
@@ -3119,7 +3128,7 @@ void lock_acquired(struct lockdep_map *lock)
raw_local_irq_save(flags);
check_flags(flags);
current->lockdep_recursion = 1;
__lock_acquired(lock);
__lock_acquired(lock, ip);
current->lockdep_recursion = 0;
raw_local_irq_restore(flags);
}