svn commit: r314185 - head/sys/kern
Mateusz Guzik
mjg at FreeBSD.org
Thu Feb 23 22:46:03 UTC 2017
Author: mjg
Date: Thu Feb 23 22:46:01 2017
New Revision: 314185
URL: https://svnweb.freebsd.org/changeset/base/314185
Log:
mtx: microoptimize lockstat handling in spin mutexes and thread lock
While here make the code compilablle on kernels with LOCK_PROFILING but without
KDTRACE_HOOKS.
Modified:
head/sys/kern/kern_mutex.c
Modified: head/sys/kern/kern_mutex.c
==============================================================================
--- head/sys/kern/kern_mutex.c Thu Feb 23 22:10:37 2017 (r314184)
+++ head/sys/kern/kern_mutex.c Thu Feb 23 22:46:01 2017 (r314185)
@@ -468,7 +468,9 @@ __mtx_lock_sleep(volatile uintptr_t *c,
u_int sleep_cnt = 0;
int64_t sleep_time = 0;
int64_t all_time = 0;
- int doing_lockstat;
+#endif
+#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
+ int doing_lockprof;
#endif
if (SCHEDULER_STOPPED())
@@ -510,13 +512,11 @@ __mtx_lock_sleep(volatile uintptr_t *c,
CTR4(KTR_LOCK,
"_mtx_lock_sleep: %s contested (lock=%p) at %s:%d",
m->lock_object.lo_name, (void *)m->mtx_lock, file, line);
-#ifdef KDTRACE_HOOKS
#ifdef LOCK_PROFILING
- doing_lockstat = 1;
-#else
- doing_lockstat = lockstat_enabled;
-#endif
- if (__predict_false(doing_lockstat))
+ doing_lockprof = 1;
+#elif KDTRACE_HOOKS
+ doing_lockprof = lockstat_enabled;
+ if (__predict_false(doing_lockprof))
all_time -= lockstat_nsecs(&m->lock_object);
#endif
@@ -631,9 +631,11 @@ __mtx_lock_sleep(volatile uintptr_t *c,
m->lock_object.lo_name, (void *)tid, file, line);
}
#endif
-#ifdef KDTRACE_HOOKS
- if (__predict_true(!doing_lockstat))
+#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
+ if (__predict_true(!doing_lockprof))
return;
+#endif
+#ifdef KDTRACE_HOOKS
all_time += lockstat_nsecs(&m->lock_object);
#endif
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(adaptive__acquire, m, contested,
@@ -689,6 +691,9 @@ _mtx_lock_spin_cookie(volatile uintptr_t
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
+#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
+ int doing_lockprof;
+#endif
if (SCHEDULER_STOPPED())
return;
@@ -713,8 +718,12 @@ _mtx_lock_spin_cookie(volatile uintptr_t
PMC_SOFT_CALL( , , lock, failed);
#endif
lock_profile_obtain_lock_failed(&m->lock_object, &contested, &waittime);
-#ifdef KDTRACE_HOOKS
- spin_time -= lockstat_nsecs(&m->lock_object);
+#ifdef LOCK_PROFILING
+ doing_lockprof = 1;
+#elif KDTRACE_HOOKS
+ doing_lockprof = lockstat_enabled;
+ if (__predict_false(doing_lockprof))
+ spin_time -= lockstat_nsecs(&m->lock_object);
#endif
for (;;) {
if (v == MTX_UNOWNED) {
@@ -740,18 +749,22 @@ _mtx_lock_spin_cookie(volatile uintptr_t
} while (v != MTX_UNOWNED);
spinlock_enter();
}
-#ifdef KDTRACE_HOOKS
- spin_time += lockstat_nsecs(&m->lock_object);
-#endif
if (LOCK_LOG_TEST(&m->lock_object, opts))
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spin done", m);
KTR_STATE0(KTR_SCHED, "thread", sched_tdname((struct thread *)tid),
"running");
+#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
+ if (__predict_true(!doing_lockprof))
+ return;
+#endif
#ifdef KDTRACE_HOOKS
+ spin_time += lockstat_nsecs(&m->lock_object);
+#endif
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
+#ifdef KDTRACE_HOOKS
if (spin_time != 0)
LOCKSTAT_RECORD1(spin__spin, m, spin_time);
#endif
@@ -771,6 +784,9 @@ thread_lock_flags_(struct thread *td, in
#ifdef KDTRACE_HOOKS
int64_t spin_time = 0;
#endif
+#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
+ int doing_lockprof = 1;
+#endif
tid = (uintptr_t)curthread;
@@ -786,8 +802,12 @@ thread_lock_flags_(struct thread *td, in
lock_delay_arg_init(&lda, &mtx_spin_delay);
-#ifdef KDTRACE_HOOKS
- spin_time -= lockstat_nsecs(&td->td_lock->lock_object);
+#ifdef LOCK_PROFILING
+ doing_lockprof = 1;
+#elif KDTRACE_HOOKS
+ doing_lockprof = lockstat_enabled;
+ if (__predict_false(doing_lockprof))
+ spin_time -= lockstat_nsecs(&td->td_lock->lock_object);
#endif
for (;;) {
retry:
@@ -843,15 +863,20 @@ retry:
break;
__mtx_unlock_spin(m); /* does spinlock_exit() */
}
+ LOCK_LOG_LOCK("LOCK", &m->lock_object, opts, m->mtx_recurse, file,
+ line);
+ WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
+
+#if defined(KDTRACE_HOOKS) || defined(LOCK_PROFILING)
+ if (__predict_true(!doing_lockprof))
+ return;
+#endif
#ifdef KDTRACE_HOOKS
spin_time += lockstat_nsecs(&m->lock_object);
#endif
if (m->mtx_recurse == 0)
LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, m,
contested, waittime, file, line);
- LOCK_LOG_LOCK("LOCK", &m->lock_object, opts, m->mtx_recurse, file,
- line);
- WITNESS_LOCK(&m->lock_object, opts | LOP_EXCLUSIVE, file, line);
#ifdef KDTRACE_HOOKS
if (spin_time != 0)
LOCKSTAT_RECORD1(thread__spin, m, spin_time);
More information about the svn-src-head
mailing list