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[2604:1380:45d1:ec00::1]) by mx.google.com with ESMTPS id c1-20020a0cca01000000b0067f153bfcd1si2973471qvk.412.2023.12.15.14.51.12 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Dec 2023 14:51:12 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-1796-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b="OQLUim/H"; spf=pass (google.com: domain of linux-kernel+bounces-1796-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-1796-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ny.mirrors.kernel.org (Postfix) with ESMTPS id 9E6CF1C24869 for ; Fri, 15 Dec 2023 22:51:12 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 39A0818ECA; Fri, 15 Dec 2023 22:51:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OQLUim/H" X-Original-To: linux-kernel@vger.kernel.org Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 6909B18EAC; Fri, 15 Dec 2023 22:51:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 73C32C433C7; Fri, 15 Dec 2023 22:51:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1702680661; bh=RXdK6WE2rb/NaaADk0qbTl/pqAk6badogzNJAS0K9TA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=OQLUim/H00s3zz/bpvwscuI7uUfp/5lz5E/vH7B+3pYZr7X29HTWIO7lN74KA0lSe 97BwWHiXBf3fGk7ieRatgGCQdsNJSamyEfcuVney0nhX6xRHCcmIe3jE5vZogpZ3qp uA1vye+1FmCTwV/LB5lg9gu6JVUDHEBHEPdBkxwXH6Yu+dCboBmMNvlchhyP5Bk5/0 8XSQVbE6IYxFwLO/hDIGzsqASXyzlzZt1cAqqHjkOILxheHYFHg9NP+7nC0shbmMPY O6dMDUxM1V4pigHnX9gkmPb/WD+pgYYQqbsOlgGnlr3B8rdZW0wdQ0T1ZXcM+OOvOE +wwZAqPbYveiQ== Date: Fri, 15 Dec 2023 14:50:59 -0800 From: Jakub Kicinski To: Sebastian Andrzej Siewior Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, "David S. Miller" , Boqun Feng , Daniel Borkmann , Eric Dumazet , Frederic Weisbecker , Ingo Molnar , Paolo Abeni , Peter Zijlstra , Thomas Gleixner , Waiman Long , Will Deacon Subject: Re: [PATCH net-next 00/24] locking: Introduce nested-BH locking. Message-ID: <20231215145059.3b42ee35@kernel.org> In-Reply-To: <20231215171020.687342-1-bigeasy@linutronix.de> References: <20231215171020.687342-1-bigeasy@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-Transfer-Encoding: 7bit On Fri, 15 Dec 2023 18:07:19 +0100 Sebastian Andrzej Siewior wrote: > The proposed way out is to introduce explicit per-CPU locks for > resources which are protected by local_bh_disable() and use those only > on PREEMPT_RT so there is no additional overhead for !PREEMPT_RT builds. As I said at LPC, complicating drivers with odd locking constructs is a no go for me.