Received: by 2002:a25:f815:0:0:0:0:0 with SMTP id u21csp3414302ybd; Fri, 28 Jun 2019 08:13:25 -0700 (PDT) X-Google-Smtp-Source: APXvYqw1lhtguSXhK+tKzCnvhTU+z3hNwGynlZLHMwPPVijGihb5iuhr6N4xvW1dRJaOMImVMliP X-Received: by 2002:a17:90b:d82:: with SMTP id bg2mr14046587pjb.87.1561734805626; Fri, 28 Jun 2019 08:13:25 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1561734805; cv=none; d=google.com; s=arc-20160816; b=t9VdeYcm0DiH45r5ss75DboTKU7LkR6HMtNYQpUuaglyLZLkwUhoUNU21tdQkGiOl/ LB7tJdlgHyEu8zN0uTd4K8Cfel/2wuPBtT4sLZR9rqeXQJqa6qZUgTa8EJPmUv1vM0lW oSmd+6F4gs83MuYOmQa63ZHqxV4kWpffP316EAl3bK/wbVOnYqlWdBz6+KSl9XhzQ3p3 qaJ+Y/xtyoAZqd32sDaPugkLltdFhOppfJokiV9eLQAGLnaSta8Pp6pRZVgdKDZWSwcZ OB1CxJmAExFQa5bSg3lSdEV8KMzc7ESL/u+gGrdR0kZXkVpD23tJ10LV4HYqE/oEC7YL GUsw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :organization:references:in-reply-to:message-id:subject:cc:to:from :date; bh=PHT+f7DGINFSLFmfzXexKNQIgOW/qFizVBD7sMJoZCU=; b=ki32vh3LtkQVV6yg0EJgA0OP0He7Ci9N88Pnnr1julOoa4Pv8lBcRbYOAc3O3tQCqE 75TJN5SKHkQn7Ukwn5IV0Sbkb/RNUpgKZ1D6uXRI/pNXzgNGeNg2bhiU+Mr9WJTLOpHu hAFjH9ET2kaS98EY8lOrgFdbdYkxqYtdQ8yCq4zHGkSPqhVn4ydwoRspNtj0p2shUne4 OFpDYw9KGr9cxolfp7fFUaUFD1qivCzZAhSA/b4La3hSREcIWnBGIsj1D/7w55tcKiGv Y5PLB3PyMmUgBGdO9TlbAhMyBaIZ1xGRWFWZ6DUONzrPy3BDeTVgOy0Ry8K8VQIEe06C Aulg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id o39si2615396pje.28.2019.06.28.08.13.08; Fri, 28 Jun 2019 08:13:25 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726863AbfF1PLE (ORCPT + 99 others); Fri, 28 Jun 2019 11:11:04 -0400 Received: from ms.lwn.net ([45.79.88.28]:35124 "EHLO ms.lwn.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726616AbfF1PLE (ORCPT ); Fri, 28 Jun 2019 11:11:04 -0400 Received: from lwn.net (localhost [127.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id 121F22B4; Fri, 28 Jun 2019 15:11:03 +0000 (UTC) Date: Fri, 28 Jun 2019 09:11:01 -0600 From: Jonathan Corbet To: Jiunn Chang Cc: skhan@linuxfoundation.org, linux-kernel-mentees@lists.linuxfoundation.org, paulmck@linux.ibm.com, josh@joshtriplett.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, joel@joelfernandes.org, rcu@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [Linux-kernel-mentees][PATCH] doc: RCU callback locks need only _bh, not necessarily _irq Message-ID: <20190628091101.5f4d35e3@lwn.net> In-Reply-To: <20190627210147.19510-1-c0d1n61at3@gmail.com> References: <20190627210147.19510-1-c0d1n61at3@gmail.com> Organization: LWN.net MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 27 Jun 2019 16:01:47 -0500 Jiunn Chang wrote: > The UP.rst file calls for locks acquired within RCU callback functions > to use _irq variants (spin_lock_irqsave() or similar), which does work, > but can be overkill. This commit therefore instead calls for _bh variants > (spin_lock_bh() or similar), while noting that _irq does work. > > Signed-off-by: Paul E. McKenney > Signed-off-by: Jiunn Chang > --- > Documentation/RCU/UP.rst | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) Applied, thanks. jon