From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4AEFE1BF311 for ; Thu, 10 Oct 2024 08:11:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728547909; cv=none; b=HnBX632oTaAvHTmmshaV+5R0e9Yj3UBkuSjakkH1jta0Xj52ZZIQ+IgiTNHjgNQGHklSEO/g2OEZzuZoZJn641h7o8xDGemPmYMlpNMH1DflXRHIcEpP2n4efOfR+hrHsUxS88AX2QHeeKO60tSpIQsAAtphYj4LFj60gM7VDl8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728547909; c=relaxed/simple; bh=R5+0wiryyjVn0yfcAfpaC/u5jemc97CY4rYW3WMi/y4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=RRa19e9RaGdF0NVRda6ih5jPhQRYVwsps3zFVJWTnhgSSad1JfudY3zSmxHGitYLWnJQfKjDGnyvyf6qlqrJHlexhrHognSh2iYMPi9Je4/gtuiqd886/n+20NJdJXqp9v/39JEbpCDyhgcDeA9Zs2UX7NKhMFOmCej3STQ01/4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=lHwio+nE; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="lHwio+nE" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=6qPxvXn9MZxVow59XRRH0RUNiQjnqXiAqsiiJ4bqLtY=; b=lHwio+nENPugc5nj2th4mDolCF 6yfvXBR8Puwtmp4JJ+N4nx+E/j6QOb/dyZoGrTCkD/o1apFasAIAYaGY1eFi2O3V1GW4QDps7PzV1 NaAYjGmK5l7L8nEtQHUrQSIDrqYNH8dLg4E5w+Kpa9Ymo4lY+PtqboYRqSqDnpY661Mk9uz+zbH1D uJRfPcGIXi6iR53Ck1HfxbPVg+sOgwUH1QLzHAypMvhOaIvxtOX6L1fJBsStVrZ8LZAal8ZXAuAq9 +izGVZ9G/aM01CtTewmKraR8eqKeowWWuLHkREAPz0G/W+Pa3D39diVBYykod1ris7MA91hy+gwEm Dgjz7Z7g==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1syoGg-00000005EX7-1sPv; Thu, 10 Oct 2024 08:11:30 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 1F54E30088D; Thu, 10 Oct 2024 10:11:30 +0200 (CEST) Date: Thu, 10 Oct 2024 10:11:29 +0200 From: Peter Zijlstra To: Sebastian Andrzej Siewior Cc: Ankur Arora , linux-kernel@vger.kernel.org, tglx@linutronix.de, paulmck@kernel.org, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, frederic@kernel.org, efault@gmx.de Subject: Re: [PATCH 3/7] rcu: fix header guard for rcu_all_qs() Message-ID: <20241010081129.GB17263@noisy.programming.kicks-ass.net> References: <20241009165411.3426937-1-ankur.a.arora@oracle.com> <20241009165411.3426937-4-ankur.a.arora@oracle.com> <20241010064123.WJjDYegr@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241010064123.WJjDYegr@linutronix.de> On Thu, Oct 10, 2024 at 08:41:23AM +0200, Sebastian Andrzej Siewior wrote: > On 2024-10-09 09:54:07 [-0700], Ankur Arora wrote: > > rcu_all_qs() is defined for !CONFIG_PREEMPT_RCU but the declaration > > is conditioned on CONFIG_PREEMPTION. > > > > With CONFIG_PREEMPT_LAZY, CONFIG_PREEMPTION=y does not imply > > CONFIG_PREEMPT_RCU=y. > > From kernel/rcu/Kconfig: > | config PREEMPT_RCU > | bool > | default y if PREEMPTION > > this looks like PREEMPT_RCU implies PREEMPTION. The point was to make PREEMPT_RCU=n possible even when PREEMPTION=y, which is fine.