From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 70686EB64DC for ; Tue, 11 Jul 2023 14:16:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=7doKxtwWtFpc28hnY/oPSQs5g4yU1v7IkEVEgr4Lml4=; b=t8ZvlIr/vXJiG0 i7lP0AbrC5Alr1lwm80wXhz5fH9Vp8r+UkditHdFtFXhIgntkoJaZiDa2X0F7kl4ro8596Yl0XxvJ QvsLTY98ao5xhHUHEg/9ZIRRgQ6ISuI50onVdpodHMyZ4IXEeSYg7ecekgH/MX65rS+ThHyTYP/EJ ISFv741ReR5to0OGZFLDP85NoP62Mn18TZtZ0Yrouj+fIu4BTcWX1Y2L3QvdfvJHmUNcmXHPM9U3y odx8z8ROAEwr0FwPT/xH+ZXcIi5lPfHvlOykfyEK1dMr6Vo6stcYZ6ijKFaYwjPRiEc2P4EUGNxsF LmWEIAoxWWYYz9fd72xA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qJE9r-00F5oK-2b; Tue, 11 Jul 2023 14:16:03 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qJE9o-00F5mm-21 for linux-arm-kernel@lists.infradead.org; Tue, 11 Jul 2023 14:16:02 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AB2991FB; Tue, 11 Jul 2023 07:16:41 -0700 (PDT) Received: from [10.57.30.34] (unknown [10.57.30.34]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CD5193F740; Tue, 11 Jul 2023 07:15:56 -0700 (PDT) Message-ID: <6143e1cd-4db7-d980-a189-b9b06f99d7c4@arm.com> Date: Tue, 11 Jul 2023 15:15:55 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH 4/4] perf: Remove unused PERF_PMU_CAP_HETEROGENEOUS_CPUS capability Content-Language: en-US To: Anshuman Khandual Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Adrian Hunter , Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Will Deacon , Kan Liang , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, irogers@google.com References: <20230710122138.1450930-1-james.clark@arm.com> <20230710122138.1450930-5-james.clark@arm.com> <96a3d12a-71d8-1779-28a3-316e1838292e@arm.com> From: James Clark In-Reply-To: <96a3d12a-71d8-1779-28a3-316e1838292e@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230711_071600_712032_6CD23B8A X-CRM114-Status: GOOD ( 20.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 11/07/2023 13:10, Anshuman Khandual wrote: > > > On 7/10/23 17:51, James Clark wrote: >> Since commit bd2756811766 ("perf: Rewrite core context handling") the >> relationship between perf_event_context and PMUs has changed so that >> the error scenario that PERF_PMU_CAP_HETEROGENEOUS_CPUS originally >> silenced no longer exists. >> >> Remove the capability to avoid confusion that it actually influences >> any perf core behavior. This change should be a no-op. >> >> Signed-off-by: James Clark >> --- >> include/linux/perf_event.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h >> index d5628a7b5eaa..3f4d941fd6c5 100644 >> --- a/include/linux/perf_event.h >> +++ b/include/linux/perf_event.h >> @@ -288,7 +288,7 @@ struct perf_event_pmu_context; >> #define PERF_PMU_CAP_EXTENDED_REGS 0x0008 >> #define PERF_PMU_CAP_EXCLUSIVE 0x0010 >> #define PERF_PMU_CAP_ITRACE 0x0020 >> -#define PERF_PMU_CAP_HETEROGENEOUS_CPUS 0x0040 >> +/* Unused 0x0040 */ > > Small nit, "Unused" marking might not be required here. > But then it would be very easy to miss that there is a free bit if I don't leave the comment. Is it really better without it? I could shift all the following ones down by one bit, but it would be a lot of work to make sure that nobody has hard coded some check for one of the bits instead of using the define somewhere. >> #define PERF_PMU_CAP_NO_EXCLUDE 0x0080 >> #define PERF_PMU_CAP_AUX_OUTPUT 0x0100 >> #define PERF_PMU_CAP_EXTENDED_HW_TYPE 0x0200 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel