From owner-svn-src-head@freebsd.org Mon Sep 9 18:31:46 2019 Return-Path: Delivered-To: svn-src-head@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 9C298DB716; Mon, 9 Sep 2019 18:31:46 +0000 (UTC) (envelope-from cse.cem@gmail.com) Received: from mail-io1-f51.google.com (mail-io1-f51.google.com [209.85.166.51]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 46RxZp3dQ7z4N6J; Mon, 9 Sep 2019 18:31:46 +0000 (UTC) (envelope-from cse.cem@gmail.com) Received: by mail-io1-f51.google.com with SMTP id b136so31132075iof.3; Mon, 09 Sep 2019 11:31:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:reply-to :from:date:message-id:subject:to:cc; bh=dPjwC65Dw8kk+xnc4IxUzGyVYnpw2uP3VQ39HDrW3Pk=; b=YhC8sZIdOB1WRvHWzA2F7FOppQwwKulwqzQBFXsG5nk1bVyNGlMMO+7XliAGYb9fCK 98tJ0S8y6HWPgzoxjUv7OrihCC0TFA/qpV22FU9azJqhg/8SInSSnzrPU4PLlqoGltHk eRWjQZSFDIBCB4GQ6jEU66zLETnW5a0JNJB2cvM/D8VAJDLzK2tkY7ORk6eBEarwhEEl DuIBOj7vs6HJFNY5AjlC/HjQHNtWWzJLCliMU5zQs2avpLvh9QK/y1qxK19NDeYKAbAa gc1WdjyyzlAB/dSPnVA5mO/9GUq3b3th+1haQwVrfWkJm1mUrveyhvNmMdvFL0U04E8o ociQ== X-Gm-Message-State: APjAAAUoSn54iBh+jc5HIZDyA29nkQ2sYbba8i0D5dMvW2Jtat1vDzLY sCjEtPrDJvpgBKnE0FZUzvHCnIst X-Google-Smtp-Source: APXvYqxwp0qGKuS20Jd9Bz6nmXzj002Rxtbim6q/kUlJmaMsmXp5/qQfKYS69RIWf0rtRtzU8U3kPg== X-Received: by 2002:a5e:960f:: with SMTP id a15mr7360448ioq.13.1568053905029; Mon, 09 Sep 2019 11:31:45 -0700 (PDT) Received: from mail-io1-f51.google.com (mail-io1-f51.google.com. [209.85.166.51]) by smtp.gmail.com with ESMTPSA id u10sm16604316ior.81.2019.09.09.11.31.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 09 Sep 2019 11:31:44 -0700 (PDT) Received: by mail-io1-f51.google.com with SMTP id b136so31131900iof.3; Mon, 09 Sep 2019 11:31:44 -0700 (PDT) X-Received: by 2002:a5d:9346:: with SMTP id i6mr9325167ioo.107.1568053904061; Mon, 09 Sep 2019 11:31:44 -0700 (PDT) MIME-Version: 1.0 References: <201909091129.x89BTxvw061871@repo.freebsd.org> In-Reply-To: <201909091129.x89BTxvw061871@repo.freebsd.org> Reply-To: cem@freebsd.org From: Conrad Meyer Date: Mon, 9 Sep 2019 11:31:32 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: svn commit: r352059 - head/sys/kern To: Konstantin Belousov Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org X-Rspamd-Queue-Id: 46RxZp3dQ7z4N6J X-Spamd-Bar: ----- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-6.00 / 15.00]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; REPLY(-4.00)[]; TAGGED_FROM(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0] Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 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: Mon, 09 Sep 2019 18:31:46 -0000 What=E2=80=99s the motivation for using more timehands? On Mon, Sep 9, 2019 at 04:30 Konstantin Belousov wrote: > Author: kib > Date: Mon Sep 9 11:29:58 2019 > New Revision: 352059 > URL: https://svnweb.freebsd.org/changeset/base/352059 > > Log: > Make timehands count selectable at boottime. > > Tested by: O'Connor, Daniel > Sponsored by: The FreeBSD Foundation > MFC after: 1 week > Differential revision: https://reviews.freebsd.org/D21563 > > Modified: > head/sys/kern/kern_tc.c > > Modified: head/sys/kern/kern_tc.c > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D > --- head/sys/kern/kern_tc.c Mon Sep 9 11:22:38 2019 (r352058) > +++ head/sys/kern/kern_tc.c Mon Sep 9 11:29:58 2019 (r352059) > @@ -83,19 +83,16 @@ struct timehands { > struct timehands *th_next; > }; > > -static struct timehands th0; > -static struct timehands th1 =3D { > - .th_next =3D &th0 > -}; > -static struct timehands th0 =3D { > +static struct timehands ths[16] =3D { > + [0] =3D { > .th_counter =3D &dummy_timecounter, > .th_scale =3D (uint64_t)-1 / 1000000, > .th_offset =3D { .sec =3D 1 }, > .th_generation =3D 1, > - .th_next =3D &th1 > + }, > }; > > -static struct timehands *volatile timehands =3D &th0; > +static struct timehands *volatile timehands =3D &ths[0]; > struct timecounter *timecounter =3D &dummy_timecounter; > static struct timecounter *timecounters =3D &dummy_timecounter; > > @@ -115,6 +112,10 @@ static int timestepwarnings; > SYSCTL_INT(_kern_timecounter, OID_AUTO, stepwarnings, CTLFLAG_RW, > ×tepwarnings, 0, "Log time steps"); > > +static int timehands_count =3D 2; > +SYSCTL_INT(_kern_timecounter, OID_AUTO, timehands_count, CTLFLAG_RDTUN, > + &timehands_count, 0, "Count of timehands in rotation"); > + > struct bintime bt_timethreshold; > struct bintime bt_tickthreshold; > sbintime_t sbt_timethreshold; > @@ -1960,8 +1961,9 @@ done: > static void > inittimecounter(void *dummy) > { > + struct timehands *thp; > u_int p; > - int tick_rate; > + int i, tick_rate; > > /* > * Set the initial timeout to > @@ -1987,6 +1989,16 @@ inittimecounter(void *dummy) > #ifdef FFCLOCK > ffclock_init(); > #endif > + > + /* Set up the requested number of timehands. */ > + if (timehands_count < 1) > + timehands_count =3D 1; > + if (timehands_count > nitems(ths)) > + timehands_count =3D nitems(ths); > + for (i =3D 1, thp =3D &ths[0]; i < timehands_count; thp =3D &ths= [i++]) > + thp->th_next =3D &ths[i]; > + thp->th_next =3D &ths[0]; > + > /* warm up new timecounter (again) and get rolling. */ > (void)timecounter->tc_get_timecount(timecounter); > (void)timecounter->tc_get_timecount(timecounter); > >