svn commit: r333052 - head/sys/vm
Rodney W. Grimes
freebsd at pdx.rh.CN85.dnsmgr.net
Fri Apr 27 14:29:34 UTC 2018
[ Charset UTF-8 unsupported, converting... ]
> Author: mjg
> Date: Fri Apr 27 05:37:35 2018
> New Revision: 333052
> URL: https://svnweb.freebsd.org/changeset/base/333052
>
> Log:
> uma: whack main zone counter update in the slow path
Remove might be a better word, whack is ambigous in this context.
> Cached counters are typically zero at this point so it performs
> avoidable atomics. Everything reading them also reads the cached
> ones, thus there is really no point.
No point in? reading them, writting them, updating them?
>
> Reviewed by: jeff
>
> Modified:
> head/sys/vm/uma_core.c
>
> Modified: head/sys/vm/uma_core.c
> ==============================================================================
> --- head/sys/vm/uma_core.c Fri Apr 27 05:36:02 2018 (r333051)
> +++ head/sys/vm/uma_core.c Fri Apr 27 05:37:35 2018 (r333052)
> @@ -2329,14 +2329,6 @@ zalloc_start:
> cpu = curcpu;
> cache = &zone->uz_cpu[cpu];
>
> - /*
> - * Since we have locked the zone we may as well send back our stats.
> - */
> - atomic_add_long(&zone->uz_allocs, cache->uc_allocs);
> - atomic_add_long(&zone->uz_frees, cache->uc_frees);
> - cache->uc_allocs = 0;
> - cache->uc_frees = 0;
> -
> /* See if we lost the race to fill the cache. */
> if (cache->uc_allocbucket != NULL) {
> ZONE_UNLOCK(zone);
>
>
--
Rod Grimes rgrimes at freebsd.org
More information about the svn-src-head
mailing list