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-rw-r--r--kernel/locking/mutex.c29
1 files changed, 18 insertions, 11 deletions
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index db1913611192..d973fe6041bf 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -30,6 +30,9 @@
#include <linux/debug_locks.h>
#include <linux/osq_lock.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/lock.h>
+
#ifndef CONFIG_PREEMPT_RT
#include "mutex.h"
@@ -367,8 +370,7 @@ bool mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner,
/*
* Use vcpu_is_preempted to detect lock holder preemption issue.
*/
- if (!owner->on_cpu || need_resched() ||
- vcpu_is_preempted(task_cpu(owner))) {
+ if (!owner_on_cpu(owner) || need_resched()) {
ret = false;
break;
}
@@ -403,14 +405,8 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
* structure won't go away during the spinning period.
*/
owner = __mutex_owner(lock);
-
- /*
- * As lock holder preemption issue, we both skip spinning if task is not
- * on cpu or its cpu is preempted
- */
-
if (owner)
- retval = owner->on_cpu && !vcpu_is_preempted(task_cpu(owner));
+ retval = owner_on_cpu(owner);
/*
* If lock->owner is not set, the mutex has been released. Return true
@@ -606,12 +602,14 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
preempt_disable();
mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
+ trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN);
if (__mutex_trylock(lock) ||
mutex_optimistic_spin(lock, ww_ctx, NULL)) {
/* got the lock, yay! */
lock_acquired(&lock->dep_map, ip);
if (ww_ctx)
ww_mutex_set_context_fastpath(ww, ww_ctx);
+ trace_contention_end(lock, 0);
preempt_enable();
return 0;
}
@@ -648,6 +646,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
}
set_current_state(state);
+ trace_contention_begin(lock, LCB_F_MUTEX);
for (;;) {
bool first;
@@ -687,10 +686,16 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
* state back to RUNNING and fall through the next schedule(),
* or we must see its unlock and acquire.
*/
- if (__mutex_trylock_or_handoff(lock, first) ||
- (first && mutex_optimistic_spin(lock, ww_ctx, &waiter)))
+ if (__mutex_trylock_or_handoff(lock, first))
break;
+ if (first) {
+ trace_contention_begin(lock, LCB_F_MUTEX | LCB_F_SPIN);
+ if (mutex_optimistic_spin(lock, ww_ctx, &waiter))
+ break;
+ trace_contention_begin(lock, LCB_F_MUTEX);
+ }
+
raw_spin_lock(&lock->wait_lock);
}
raw_spin_lock(&lock->wait_lock);
@@ -714,6 +719,7 @@ acquired:
skip_wait:
/* got the lock - cleanup and rejoice! */
lock_acquired(&lock->dep_map, ip);
+ trace_contention_end(lock, 0);
if (ww_ctx)
ww_mutex_lock_acquired(ww, ww_ctx);
@@ -726,6 +732,7 @@ err:
__set_current_state(TASK_RUNNING);
__mutex_remove_waiter(lock, &waiter);
err_early_kill:
+ trace_contention_end(lock, ret);
raw_spin_unlock(&lock->wait_lock);
debug_mutex_free_waiter(&waiter);
mutex_release(&lock->dep_map, ip);