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[23.128.96.18]) by mx.google.com with ESMTP id gc10si6371935ejb.614.2020.09.27.17.16.42; Sun, 27 Sep 2020 17:17:05 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@joelfernandes.org header.s=google header.b=ukJOK6nb; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726421AbgI1ANp (ORCPT + 99 others); Sun, 27 Sep 2020 20:13:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726392AbgI1ANp (ORCPT ); Sun, 27 Sep 2020 20:13:45 -0400 Received: from mail-qk1-x743.google.com (mail-qk1-x743.google.com [IPv6:2607:f8b0:4864:20::743]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CF199C0613CF for ; Sun, 27 Sep 2020 17:13:44 -0700 (PDT) Received: by mail-qk1-x743.google.com with SMTP id g72so8568328qke.8 for ; Sun, 27 Sep 2020 17:13:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=1KIK63/wTLAsMMEvtCu6RaqQGvZckuPgS8U08wx8ekI=; b=ukJOK6nbxwSQRhtC+rI6Zriz5UbWGyHGQ1Apiw7mkRvgACIByAGvFvG58eT1IbleYl +mwtLrVmpwblkHxhyNKTTVCPvbhnLZ9Ts35D1GwDqYKvIUSw+AIhHQp8oEvryhnohkY0 my8/0Xr+YCAzJ8i1AtXvYo8F2LGzEQkwLEMQM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=1KIK63/wTLAsMMEvtCu6RaqQGvZckuPgS8U08wx8ekI=; b=ePMvfJO60FI3cBpqriudAcBGs2Pk2FZtLrMJpkQjB6X1j47mCoZxckOCtzI5jM2tlF cqXP+AhupsnyIhuLLaRB26FHNziEqFlHnhAkFEvWNk2hIGPGHxCsMEFOEZ/Bu+kAq/hI eZrJJ4c7bob0jm9wMJYLG6994WejKZdav5VYl4uzYdGuFyT+cEDdrW/Q9D5WIx0EfDz7 3cO2hifglyfxG23di/TIoSmPiYYDOXkvgcTvCz23R8XM215oorRkeJPJ50uUhfePZbzS aovtT3OJ6BerHimwsbmgIqz/FCzpQqAttfo2+5KIXVwLLIBOgWihScWvmWRsXuFly2P3 hffg== X-Gm-Message-State: AOAM532EuKaovpJX07e5xzAIEb3OaE19u9Uz9IFiMbBcXOYWE8Sjz9BC oxwShyNmtJgDsNZvosr5MM62Ug== X-Received: by 2002:a05:620a:2118:: with SMTP id l24mr9993709qkl.298.1601252023946; Sun, 27 Sep 2020 17:13:43 -0700 (PDT) Received: from localhost ([2620:15c:6:12:cad3:ffff:feb3:bd59]) by smtp.gmail.com with ESMTPSA id l5sm8837846qtc.28.2020.09.27.17.13.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 27 Sep 2020 17:13:43 -0700 (PDT) Date: Sun, 27 Sep 2020 20:13:42 -0400 From: Joel Fernandes To: Neeraj Upadhyay Cc: paulmck@kernel.org, josh@joshtriplett.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, rcu@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] rcu: Clarify nocb kthreads naming in RCU_NOCB_CPU config Message-ID: <20200928001342.GD500818@google.com> References: <1600929250-20344-1-git-send-email-neeraju@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1600929250-20344-1-git-send-email-neeraju@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 24, 2020 at 12:04:10PM +0530, Neeraj Upadhyay wrote: > Clarify the "x" in rcuox/N naming in RCU_NOCB_CPU config > description. > Reviewed-by: Joel Fernandes (Google) thanks, - Joel > Signed-off-by: Neeraj Upadhyay > --- > kernel/rcu/Kconfig | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > > diff --git a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig > index b71e21f..5b22747 100644 > --- a/kernel/rcu/Kconfig > +++ b/kernel/rcu/Kconfig > @@ -227,11 +227,12 @@ config RCU_NOCB_CPU > specified at boot time by the rcu_nocbs parameter. For each > such CPU, a kthread ("rcuox/N") will be created to invoke > callbacks, where the "N" is the CPU being offloaded, and where > - the "p" for RCU-preempt (PREEMPTION kernels) and "s" for RCU-sched > - (!PREEMPTION kernels). Nothing prevents this kthread from running > - on the specified CPUs, but (1) the kthreads may be preempted > - between each callback, and (2) affinity or cgroups can be used > - to force the kthreads to run on whatever set of CPUs is desired. > + the "x" is "p" for RCU-preempt (PREEMPTION kernels) and "s" for > + RCU-sched (!PREEMPTION kernels). Nothing prevents this kthread > + from running on the specified CPUs, but (1) the kthreads may be > + preempted between each callback, and (2) affinity or cgroups can > + be used to force the kthreads to run on whatever set of CPUs is > + desired. > > Say Y here if you want to help to debug reduced OS jitter. > Say N here if you are unsure. > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >