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| author | scottl <scottl@FreeBSD.org> | 2004-07-18 15:59:03 +0000 |
|---|---|---|
| committer | scottl <scottl@FreeBSD.org> | 2004-07-18 15:59:03 +0000 |
| commit | 7ad60316cd2a6fab33bff1ecd701c1d696895b96 (patch) | |
| tree | ac22ab2a20ec2a247773c0b4fbd9fd368f767eb2 /sys | |
| parent | cf328c10576453a3e63ec1ff22f92f1b352db615 (diff) | |
| download | FreeBSD-src-7ad60316cd2a6fab33bff1ecd701c1d696895b96.zip FreeBSD-src-7ad60316cd2a6fab33bff1ecd701c1d696895b96.tar.gz | |
Enable ADAPTIVE_MUTEXES by default by changing the sense of the option to
NO_ADAPTIVE_MUTEXES. This option has been enabled by default on amd64 for
quite some time, and has been extensively tested on i386 and sparc64. It
shows measurable performance gains in many circumstances, and few negative
effects. It would be nice in t he future if adaptive mutexes actually went
to sleep after a certain amount of spinning, but that will require quite a
bit more testing.
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/amd64/conf/GENERIC | 1 | ||||
| -rw-r--r-- | sys/conf/NOTES | 5 | ||||
| -rw-r--r-- | sys/conf/options | 2 | ||||
| -rw-r--r-- | sys/kern/kern_mutex.c | 6 |
4 files changed, 7 insertions, 7 deletions
diff --git a/sys/amd64/conf/GENERIC b/sys/amd64/conf/GENERIC index 4cd44a4..87ca19f 100644 --- a/sys/amd64/conf/GENERIC +++ b/sys/amd64/conf/GENERIC @@ -28,7 +28,6 @@ ident GENERIC makeoptions DEBUG=-g # Build kernel with gdb(1) debug symbols options SCHED_ULE # ULE scheduler -options ADAPTIVE_MUTEXES # mutexes first spin lock, then sleep options INET # InterNETworking options INET6 # IPv6 communications protocols options FFS # Berkeley Fast Filesystem diff --git a/sys/conf/NOTES b/sys/conf/NOTES index 0ec51a5..6e33605 100644 --- a/sys/conf/NOTES +++ b/sys/conf/NOTES @@ -169,8 +169,9 @@ options SMP # Symmetric MultiProcessor Kernel # ADAPTIVE_MUTEXES changes the behavior of blocking mutexes to spin # if the thread that currently owns the mutex is executing on another -# CPU. -options ADAPTIVE_MUTEXES +# CPU. This behaviour is enabled by default, so this option can be used +# to disable it. +options NO_ADAPTIVE_MUTEXES # MUTEX_NOINLINE forces mutex operations to call functions to perform each # operation rather than inlining the simple cases. This can be used to diff --git a/sys/conf/options b/sys/conf/options index 042a025..d1dcb2a 100644 --- a/sys/conf/options +++ b/sys/conf/options @@ -56,7 +56,7 @@ KDB_TRACE opt_kdb.h KDB_UNATTENDED opt_kdb.h # Miscellaneous options. -ADAPTIVE_MUTEXES +NO_ADAPTIVE_MUTEXES ALQ CODA_COMPAT_5 opt_coda.h COMPAT_43 opt_compat.h diff --git a/sys/kern/kern_mutex.c b/sys/kern/kern_mutex.c index 662cd4c..ffb75e3 100644 --- a/sys/kern/kern_mutex.c +++ b/sys/kern/kern_mutex.c @@ -421,7 +421,7 @@ _mtx_lock_sleep(struct mtx *m, int opts, const char *file, int line) { struct turnstile *ts; struct thread *td = curthread; -#if defined(SMP) && defined(ADAPTIVE_MUTEXES) +#if defined(SMP) && !defined(NO_ADAPTIVE_MUTEXES) struct thread *owner; #endif uintptr_t v; @@ -503,7 +503,7 @@ _mtx_lock_sleep(struct mtx *m, int opts, const char *file, int line) continue; } -#if defined(SMP) && defined(ADAPTIVE_MUTEXES) +#if defined(SMP) && !defined(NO_ADAPTIVE_MUTEXES) /* * If the current owner of the lock is executing on another * CPU, spin instead of blocking. @@ -518,7 +518,7 @@ _mtx_lock_sleep(struct mtx *m, int opts, const char *file, int line) } continue; } -#endif /* SMP && ADAPTIVE_MUTEXES */ +#endif /* SMP && !NO_ADAPTIVE_MUTEXES */ /* * We definitely must sleep for this lock. |
