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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BBE8EC7EE23 for ; Mon, 29 May 2023 04:51:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231466AbjE2Ev3 (ORCPT ); Mon, 29 May 2023 00:51:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231570AbjE2EvH (ORCPT ); Mon, 29 May 2023 00:51:07 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BC1A549C3; Sun, 28 May 2023 21:44:25 -0700 (PDT) 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 10F6CAB6; Sun, 28 May 2023 21:36:01 -0700 (PDT) Received: from [10.162.40.17] (a077893.blr.arm.com [10.162.40.17]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 168683F64C; Sun, 28 May 2023 21:35:10 -0700 (PDT) Message-ID: <632289e3-6f3c-20b9-0454-77d6295c1c87@arm.com> Date: Mon, 29 May 2023 10:05:07 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH V10 00/10] arm64/perf: Enable branch stack sampling Content-Language: en-US To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com Cc: Mark Brown , James Clark , Rob Herring , Marc Zyngier , Suzuki Poulose , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , linux-perf-users@vger.kernel.org References: <20230517022410.722287-1-anshuman.khandual@arm.com> From: Anshuman Khandual In-Reply-To: <20230517022410.722287-1-anshuman.khandual@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/17/23 07:54, Anshuman Khandual wrote: > This series enables perf branch stack sampling support on arm64 platform > via a new arch feature called Branch Record Buffer Extension (BRBE). All > relevant register definitions could be accessed here. > > https://developer.arm.com/documentation/ddi0601/2021-12/AArch64-Registers > > This series applies on 6.4-rc2. > > Changes in V10: > > - Rebased the series on v6.4-rc2 > - Moved ARMV8 PMUV3 changes inside drivers/perf/arm_pmuv3.c > - Moved BRBE driver changes inside drivers/perf/arm_brbe.[c|h] > - Moved the WARN_ON() inside the if condition in armv8pmu_handle_irq() Hello Will/Mark, There was a crash reported on V9 (applicable here in V10 as well) because of accessing event->pmu_ctx->task_ctx_data during a PMU IRQ for per-cpu events, where it would not have been allocated in the first place. I have proposed a fix for that on the other thread [1]. Besides, does the series looks good in the current form ? Unless there are other comments, will respin with the fix later in the week. Thank you. [1] https://lore.kernel.org/linux-arm-kernel/d02df808-6d2b-c24b-bc8d-8f4859c0c71b@arm.com/ - Anshuman