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| author | mav <mav@FreeBSD.org> | 2013-03-12 06:58:49 +0000 |
|---|---|---|
| committer | mav <mav@FreeBSD.org> | 2013-03-12 06:58:49 +0000 |
| commit | ca616198e5ffd9e04aa3190d1c3ff9b78383b083 (patch) | |
| tree | 95fcd091ce327eb126b36b8374f04bc80e63216f /sys/kern/kern_synch.c | |
| parent | 9b31bc755831124ab769b7338fe5d4d1e21f20bf (diff) | |
| download | FreeBSD-src-ca616198e5ffd9e04aa3190d1c3ff9b78383b083.zip FreeBSD-src-ca616198e5ffd9e04aa3190d1c3ff9b78383b083.tar.gz | |
Make kern_nanosleep() and pause_sbt() to use per-CPU sleep queues.
This removes significant sleep queue lock congestion on multithreaded
microbenchmarks, making them scale to multiple CPUs almost linearly.
Diffstat (limited to 'sys/kern/kern_synch.c')
| -rw-r--r-- | sys/kern/kern_synch.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index 5aae8d8..81471ca 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -85,7 +85,7 @@ SYSINIT(synch_setup, SI_SUB_KICK_SCHEDULER, SI_ORDER_FIRST, synch_setup, NULL); int hogticks; -static int pause_wchan; +static uint8_t pause_wchan[MAXCPU]; static struct callout loadav_callout; @@ -198,7 +198,8 @@ _sleep(void *ident, struct lock_object *lock, int priority, if (TD_ON_SLEEPQ(td)) sleepq_remove(td, td->td_wchan); - if (ident == &pause_wchan) + if ((uint8_t *)ident >= &pause_wchan[0] && + (uint8_t *)ident <= &pause_wchan[MAXCPU - 1]) sleepq_flags = SLEEPQ_PAUSE; else sleepq_flags = SLEEPQ_SLEEP; @@ -372,7 +373,7 @@ pause_sbt(const char *wmesg, sbintime_t sbt, sbintime_t pr, int flags) DELAY((sbt & 0xffffffff) / SBT_1US); return (0); } - return (_sleep(&pause_wchan, NULL, 0, wmesg, sbt, pr, flags)); + return (_sleep(&pause_wchan[curcpu], NULL, 0, wmesg, sbt, pr, flags)); } /* |
