Date: Fri, 27 Apr 2018 16:35:45 +0200 From: Mateusz Guzik <mjguzik@gmail.com> To: rgrimes@freebsd.org Cc: Mateusz Guzik <mjg@freebsd.org>, src-committers <src-committers@freebsd.org>, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r333052 - head/sys/vm Message-ID: <CAGudoHHqVe27-cpggLufaGk_LQCnvBtWbFtWuy1UCWyOJEeQGQ@mail.gmail.com> In-Reply-To: <201804271429.w3RETMCl006821@pdx.rh.CN85.dnsmgr.net> References: <201804270537.w3R5bZIl064515@repo.freebsd.org> <201804271429.w3RETMCl006821@pdx.rh.CN85.dnsmgr.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Apr 27, 2018 at 4:29 PM, Rodney W. Grimes < freebsd@pdx.rh.cn85.dnsmgr.net> wrote: > [ 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. > > Ok. > > 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? > No point in doing the update, hence the removal. > > > > > 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@freebsd.org > -- Mateusz Guzik <mjguzik gmail.com>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAGudoHHqVe27-cpggLufaGk_LQCnvBtWbFtWuy1UCWyOJEeQGQ>