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Cache the value of curthread in the _get_sleep_lock() and _get_spin_lock()

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macros and pass the value to the associated _mtx_*() functions to avoid
more curthread dereferences in the function implementations.  This provided
a very modest perf improvement in some benchmarks.

Suggested by:	rwatson
Tested by:	scottl
This commit is contained in:
jhb 2004-08-04 20:18:45 +00:00
parent 687b2969b7
commit a47d4b18d5
2 changed files with 20 additions and 13 deletions
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9
sys/kern/kern_mutex.c
View File

@ -417,10 +417,10 @@ _mtx_trylock(struct mtx *m, int opts, const char *file, int line)
* sleep waiting for it), or if we need to recurse on it.
*/
void
_mtx_lock_sleep(struct mtx *m, int opts, const char *file, int line)
_mtx_lock_sleep(struct mtx *m, struct thread *td, int opts, const char *file,
int line)
{
struct turnstile *ts;
struct thread *td = curthread;
#if defined(SMP) && !defined(NO_ADAPTIVE_MUTEXES)
struct thread *owner;
#endif
@ -562,7 +562,8 @@ _mtx_lock_sleep(struct mtx *m, int opts, const char *file, int line)
* is handled inline.
*/
void
_mtx_lock_spin(struct mtx *m, int opts, const char *file, int line)
_mtx_lock_spin(struct mtx *m, struct thread *td, int opts, const char *file,
int line)
{
int i = 0;
@ -570,7 +571,7 @@ _mtx_lock_spin(struct mtx *m, int opts, const char *file, int line)
CTR1(KTR_LOCK, "_mtx_lock_spin: %p spinning", m);
for (;;) {
if (_obtain_lock(m, curthread))
if (_obtain_lock(m, td))
break;
/* Give interrupts a chance while we spin. */

24
sys/sys/mutex.h
View File

@ -100,17 +100,19 @@ void mtx_init(struct mtx *m, const char *name, const char *type, int opts);
void mtx_destroy(struct mtx *m);
void mtx_sysinit(void *arg);
void mutex_init(void);
void _mtx_lock_sleep(struct mtx *m, int opts, const char *file, int line);
void _mtx_lock_sleep(struct mtx *m, struct thread *td, int opts,
const char *file, int line);
void _mtx_unlock_sleep(struct mtx *m, int opts, const char *file, int line);
void _mtx_lock_spin(struct mtx *m, int opts, const char *file, int line);
void _mtx_lock_spin(struct mtx *m, struct thread *td, int opts,
const char *file, int line);
void _mtx_unlock_spin(struct mtx *m, int opts, const char *file, int line);
int _mtx_trylock(struct mtx *m, int opts, const char *file, int line);
void _mtx_lock_flags(struct mtx *m, int opts, const char *file, int line);
void _mtx_unlock_flags(struct mtx *m, int opts, const char *file, int line);
void _mtx_lock_spin_flags(struct mtx *m, int opts, const char *file,
int line);
int line);
void _mtx_unlock_spin_flags(struct mtx *m, int opts, const char *file,
int line);
int line);
#ifdef INVARIANT_SUPPORT
void _mtx_assert(struct mtx *m, int what, const char *file, int line);
#endif
@ -144,8 +146,10 @@ void _mtx_assert(struct mtx *m, int what, const char *file, int line);
*/
#ifndef _get_sleep_lock
#define _get_sleep_lock(mp, tid, opts, file, line) do { \
if (!_obtain_lock((mp), (tid))) \
_mtx_lock_sleep((mp), (opts), (file), (line)); \
struct thread *_tid = (tid); \
\
if (!_obtain_lock((mp), _tid)) \
_mtx_lock_sleep((mp), _tid, (opts), (file), (line)); \
} while (0)
#endif
@ -158,12 +162,14 @@ void _mtx_assert(struct mtx *m, int what, const char *file, int line);
*/
#ifndef _get_spin_lock
#define _get_spin_lock(mp, tid, opts, file, line) do { \
struct thread *_tid = (tid); \
\
critical_enter(); \
if (!_obtain_lock((mp), (tid))) { \
if ((mp)->mtx_lock == (uintptr_t)(tid)) \
if (!_obtain_lock((mp), _tid)) { \
if ((mp)->mtx_lock == (uintptr_t)_tid) \
(mp)->mtx_recurse++; \
else \
_mtx_lock_spin((mp), (opts), (file), (line)); \
_mtx_lock_spin((mp), _tid, (opts), (file), (line)); \
} \
} while (0)
#endif