From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DCBBC433E6 for ; Fri, 12 Feb 2021 14:02:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB18864DB1 for ; Fri, 12 Feb 2021 14:02:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231599AbhBLOCg (ORCPT ); Fri, 12 Feb 2021 09:02:36 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:29038 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230493AbhBLOCb (ORCPT ); Fri, 12 Feb 2021 09:02:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613138465; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=lMH8Jy+Ac2exXElrSB53MclXMZkH36voPPBwm8uMTT8=; b=OicdHgx7ULvGTF7fd71z6srkch0gBeTHIurqY6jVns2n8DZmP6BNPcydZJ27lwSK5/l5l/ ORPjMgHKSYR0ji02XURG8fGPYDbW7yE19OzlnFLkxKhtaO1QtgSXphRPfSM8Z/Bl6xCB1h VVSRrkOj38BEs+5WCFjl7JgX4YJswKE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-436-haYVU5a1Of6QesRuLmtI6Q-1; Fri, 12 Feb 2021 09:01:03 -0500 X-MC-Unique: haYVU5a1Of6QesRuLmtI6Q-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 96E49801981; Fri, 12 Feb 2021 14:01:02 +0000 (UTC) Received: from fuller.cnet (ovpn-112-8.gru2.redhat.com [10.97.112.8]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5669F6E528; Fri, 12 Feb 2021 14:01:02 +0000 (UTC) Received: by fuller.cnet (Postfix, from userid 1000) id A63AA416D87F; Fri, 12 Feb 2021 11:00:41 -0300 (-03) Date: Fri, 12 Feb 2021 11:00:41 -0300 From: Marcelo Tosatti To: Frederic Weisbecker Cc: Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: [patch 2/3] nohz: change signal tick dependency to wakeup CPUs of member tasks Message-ID: <20210212140041.GA182392@fuller.cnet> References: <20210128202134.608115362@fuller.cnet> <20210128202235.849263653@fuller.cnet> <20210212122521.GA90839@lothringen> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210212122521.GA90839@lothringen> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 12, 2021 at 01:25:21PM +0100, Frederic Weisbecker wrote: > On Thu, Jan 28, 2021 at 05:21:36PM -0300, Marcelo Tosatti wrote: > > Rather than waking up all nohz_full CPUs on the system, only wakeup > > the target CPUs of member threads of the signal. > > > > Reduces interruptions to nohz_full CPUs. > > > > Signed-off-by: Marcelo Tosatti > > > > Index: linux-2.6/kernel/time/tick-sched.c > > =================================================================== > > --- linux-2.6.orig/kernel/time/tick-sched.c > > +++ linux-2.6/kernel/time/tick-sched.c > > @@ -444,9 +444,20 @@ EXPORT_SYMBOL_GPL(tick_nohz_dep_clear_ta > > * Set a per-taskgroup tick dependency. Posix CPU timers need this in order to elapse > > * per process timers. > > */ > > -void tick_nohz_dep_set_signal(struct signal_struct *sig, enum tick_dep_bits > > bit) > > Why not keeping the signal struct as a parameter? > > Thanks. All callers use "struct signal_struct *sig = tsk->signal" as signal parameter anyway... Can change parameters to (task, signal, bit) if you prefer.