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[2620:137:e000::1:20]) by mx.google.com with ESMTP id s22-20020a632c16000000b0043a067266cdsi31665678pgs.40.2022.10.24.03.24.17; Mon, 24 Oct 2022 03:24:28 -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=OncPPm2e; 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 S229572AbiJXKAj (ORCPT + 99 others); Mon, 24 Oct 2022 06:00:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229838AbiJXKAc (ORCPT ); Mon, 24 Oct 2022 06:00:32 -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 BAEF740E37 for ; Mon, 24 Oct 2022 03:00:30 -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-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=G8UKir9gg9i/9nT/L0vrBr4zL64OWY3kKm2Uqw5po/c=; b=OncPPm2eB6p6tyx8LFabIEegh7 pAH9YpmDFpphRQnjAXEjKQbjgcEO9SzE8DCbDhEgpHFPCROfx9oC644bPKMOHNZPIOcE4WFZHrf8t kK1bFHSSZDmXE31QGC/SO1Sy+e6zfJLQINDtS/AKGx+Aj/jzzKM/FJKGHZIFDGVBX2kUWDCh021wt dq31qzD/5yyWRfZKsceMWHdAEblTvRYx+yT528/V2d9+9aXP8qUTXceLw/y+17RvnokxzZmQ5fr+E pLeRvmJlAGzm+uDOZCovQ/MGNhGFxnay5eCfR1vnazG/i/LvoQ7rVNkfu/HAPoMS2/68WaGAhhXZK Q3J2pr3g==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1omuFh-00629h-04; Mon, 24 Oct 2022 10:00:13 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 01B1E300205; Mon, 24 Oct 2022 12:00:12 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id D927D205CCF48; Mon, 24 Oct 2022 12:00:11 +0200 (CEST) Date: Mon, 24 Oct 2022 12:00:11 +0200 From: Peter Zijlstra To: Hao Jia Cc: mingo@redhat.com, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, mgorman@techsingularity.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/2] Optimize the process of scanning CPU for some functions Message-ID: References: <20221021061558.34767-1-jiahao.os@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221021061558.34767-1-jiahao.os@bytedance.com> 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 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 Fri, Oct 21, 2022 at 02:15:56PM +0800, Hao Jia wrote: > These two patches optimize the process of scanning the CPU by > adjusting the search order or breaking the loop. Is it really optimization, as in it now runs measurably faster, or just cleanups?