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[2620:137:e000::1:20]) by mx.google.com with ESMTP id f17-20020a50fe11000000b004284d9f0f6csi12326090edt.21.2022.05.10.03.52.21; Tue, 10 May 2022 03:52:45 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=O9nROi0W; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238953AbiEJJj1 (ORCPT + 99 others); Tue, 10 May 2022 05:39:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238978AbiEJJjZ (ORCPT ); Tue, 10 May 2022 05:39:25 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82B9B28FEAE; Tue, 10 May 2022 02:35:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=kI3usnv3cvSu4CK/ziEmj9I3Q9wcT4zQJngj+G2T8jc=; b=O9nROi0WT4KAsJcqjNTCmI5mNa SrMqjABCnuLu9GkShkbEoD2JqLJCcIKwNJ1yRqFQjFpTeKA5GAg93l9k1E7RFM2id432ABdGThpc+ ZhWI6utuGdVTRxLJvvXGU/nI6EUdaVGSttg/tAawdiaO3XWZxXBcsKpuAyncfs6GElHSZHqTsFvlP tku4WPChkK8OWTYEnU9qKUhdn1x49U3EW60E6lX00RcVET8a6o9d+V9CyB7+4NCCPuuZMXyF6NOzu pGkA4e6oUpaTiaWO58lteasuiJA5TB5/Ux4f250U9EJgEPsmmdgDlmekkIo5YTUGXykim9kvnryA8 bsjD5Y1g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1noMGs-00Co3Q-WF; Tue, 10 May 2022 09:35:11 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id B7596981011; Tue, 10 May 2022 11:35:08 +0200 (CEST) Date: Tue, 10 May 2022 11:35:08 +0200 From: Peter Zijlstra To: Song Liu Cc: Josh Poimboeuf , Rik van Riel , Song Liu , Linux Kernel Mailing List , "live-patching@vger.kernel.org" , Ingo Molnar , "vincent.guittot@linaro.org" , Josh Poimboeuf , "joe.lawrence@redhat.com" , Kernel Team Subject: Re: [RFC] sched,livepatch: call stop_one_cpu in klp_check_and_switch_task Message-ID: <20220510093508.GL76023@worktop.programming.kicks-ass.net> References: <20220507174628.2086373-1-song@kernel.org> <20220509115227.6075105e@imladris.surriel.com> <20220509180004.zmvhz65xlncwqrrc@treble> <68f91fb233d5bf82e29cc5c6960a62863b297db3.camel@surriel.com> <20220509191745.yk2txsa4cv3ypf6k@treble> <1f94c48b4e0e7d73a689a076f78f0892095b4d89.camel@surriel.com> <20220509200949.vzx4g5xpebomkok4@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 10, 2022 at 12:32:02AM +0000, Song Liu wrote: > cond_sched() feels like a natural “transition point” to me, and it You have to think of cond_resched() as a NOP.