From owner-svn-src-head@freebsd.org Fri Apr 27 14:35:46 2018 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 8BD2FFA92C3; Fri, 27 Apr 2018 14:35:46 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: from mail-qt0-x243.google.com (mail-qt0-x243.google.com [IPv6:2607:f8b0:400d:c0d::243]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 22F8382F62; Fri, 27 Apr 2018 14:35:46 +0000 (UTC) (envelope-from mjguzik@gmail.com) Received: by mail-qt0-x243.google.com with SMTP id g13-v6so2508253qth.8; Fri, 27 Apr 2018 07:35:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=0jMC8cyPeqmq0iTHoIxMtGiM+7LLI5SDw/ny+wwwnMo=; b=lsQCH5fmuSAj3ANGdNLH7Jhf9XzDj5sQu5gIM5fnEXDtdj+/PZZvtBhOTcdhGqhkPg sDlZLuRP/2aRKR46xq55wbAB4SfVftVyPXDYbjhTp/MjbCEC/S8rqBpQvQ0V/89lE0J0 3SDGoIbNPABcVqNE+lA0vwYpqbhRH9mX5ZKlsXABbRJ3QpH/cfNbydIt82Gjo46NmgEc yyFmjKyFinoPJuBDgAOwtEt/KG2ZnyxRWSnh11CLM2U4ltY5GqeRbPACUuPbxotLOVXq hsnv+B5tjEt0mGPQvpndvWGvaP2AdiYsX+Cy3+xEfSN1H09UDZfEqh3iT3Wsah9E9HS2 s/mQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=0jMC8cyPeqmq0iTHoIxMtGiM+7LLI5SDw/ny+wwwnMo=; b=mQnMcbiT7jWiqP4w8ngCqw6CtA7tjBsqrRBZGbkNgZk/Va4EN+JZlhpr8BgPVY8c5P THA0l3mCmzXAEr86OHFRXzt5SyBmdt1ELD2KCBzVKrjtD3e6czIak6tjQti/jYsm5W6d d9QnOGfAFwndAGydy7X6vyl2k8tUuH1FE7bQ4OMRyw71o7N0ZHy5SAZBHZaUBMAtdaCa vbP29gLZtIkfFs5QbQUr5uf7B+LnJ8Sw6KjwZa65g5HXgWTrbmTEg9FuaVVAydIsIx3V Yw5fzHB4W1GO7lw5nyt/59FIKrZvWz10mPaU3Ik65aGDamdunael31foO3BlzcKR6o8L ZL4Q== X-Gm-Message-State: ALQs6tA9mCY5Oo6bgrs4iR19Ehf67zXjOwlol81GcVJWKe5WEnZHpap/ 1SCnyt1TFNvvMoU8rhVIV61At6LsDjWfbtx82Z8= X-Google-Smtp-Source: AB8JxZo61eC7irs5MSfniOg+KH5jOU1mLPfgAky5nFSrYUVSmxayrWNpTv4VIf7XpEsdhUrZ7uh4Tax94TwBhPxgx3Y= X-Received: by 2002:aed:3edd:: with SMTP id o29-v6mr2269036qtf.248.1524839745660; Fri, 27 Apr 2018 07:35:45 -0700 (PDT) MIME-Version: 1.0 Received: by 10.200.28.74 with HTTP; Fri, 27 Apr 2018 07:35:45 -0700 (PDT) In-Reply-To: <201804271429.w3RETMCl006821@pdx.rh.CN85.dnsmgr.net> References: <201804270537.w3R5bZIl064515@repo.freebsd.org> <201804271429.w3RETMCl006821@pdx.rh.CN85.dnsmgr.net> From: Mateusz Guzik Date: Fri, 27 Apr 2018 16:35:45 +0200 Message-ID: Subject: Re: svn commit: r333052 - head/sys/vm To: rgrimes@freebsd.org Cc: Mateusz Guzik , src-committers , svn-src-all@freebsd.org, svn-src-head@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 27 Apr 2018 14:35:46 -0000 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