lockdep: Use cpu_clock() for lockstat

Some tracepoint magic (TRACE_EVENT(lock_acquired)) relies on
the fact that lock hold times are positive and uses div64 on
that. That triggered a build warning on MIPS, and probably
causes bad output in certain circumstances as well.

Make it truly positive.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1254818502.21044.112.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2009-10-09 10:12:41 +02:00 committed by Ingo Molnar
parent 36a07902c2
commit 3365e77987

View file

@ -142,6 +142,11 @@ 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 inline u64 lockstat_clock(void)
{
return cpu_clock(smp_processor_id());
}
static int lock_point(unsigned long points[], unsigned long ip)
{
int i;
@ -158,7 +163,7 @@ static int lock_point(unsigned long points[], unsigned long ip)
return i;
}
static void lock_time_inc(struct lock_time *lt, s64 time)
static void lock_time_inc(struct lock_time *lt, u64 time)
{
if (time > lt->max)
lt->max = time;
@ -234,12 +239,12 @@ static void put_lock_stats(struct lock_class_stats *stats)
static void lock_release_holdtime(struct held_lock *hlock)
{
struct lock_class_stats *stats;
s64 holdtime;
u64 holdtime;
if (!lock_stat)
return;
holdtime = sched_clock() - hlock->holdtime_stamp;
holdtime = lockstat_clock() - hlock->holdtime_stamp;
stats = get_lock_stats(hlock_class(hlock));
if (hlock->read)
@ -2792,7 +2797,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
hlock->references = references;
#ifdef CONFIG_LOCK_STAT
hlock->waittime_stamp = 0;
hlock->holdtime_stamp = sched_clock();
hlock->holdtime_stamp = lockstat_clock();
#endif
if (check == 2 && !mark_irqflags(curr, hlock))
@ -3322,7 +3327,7 @@ found_it:
if (hlock->instance != lock)
return;
hlock->waittime_stamp = sched_clock();
hlock->waittime_stamp = lockstat_clock();
contention_point = lock_point(hlock_class(hlock)->contention_point, ip);
contending_point = lock_point(hlock_class(hlock)->contending_point,
@ -3345,8 +3350,7 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip)
struct held_lock *hlock, *prev_hlock;
struct lock_class_stats *stats;
unsigned int depth;
u64 now;
s64 waittime = 0;
u64 now, waittime = 0;
int i, cpu;
depth = curr->lockdep_depth;
@ -3374,7 +3378,7 @@ found_it:
cpu = smp_processor_id();
if (hlock->waittime_stamp) {
now = sched_clock();
now = lockstat_clock();
waittime = now - hlock->waittime_stamp;
hlock->holdtime_stamp = now;
}