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 878F6C4345F for ; Fri, 12 Apr 2024 08:22:53 +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=Q76m+8VyXMdrOMjQ6GAA6eBHFtDdi+ZZ2zm9D9Phy/0=; b=byIPLFNWMq/WZM oHUnydy06QgZS0d18/vMAnN49q+u252W7ZSXj4z/qcB1K6+5WeLwxH8CthdRw7wFS8F3Whnv5Cae+ 3MObli1JP9dSS2XKcMKHWqmTkEiQyRH4OD7et4MHZb/S/lGlDIBIUcSovPpJj+cs1itvay78GB/TX DqFKydjAr8bvUo3wRIh7dkTd72SwakJgQhl5CbYAmuzdAQNoNN5kg+RZPosW/UyUel40x5LoqnsPT beCQAzZei4Z/jxjf/BsPI4X9tsQs8494mcvVmSqR7ClfecHlKf8EZSVar/aBbFY/f0kK/9grl1x01 CoWcg2PCy56CptPdjs7g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rvCBE-0000000G3ZB-0UUN; Fri, 12 Apr 2024 08:22:40 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rvCB8-0000000G3Se-0InX for linux-arm-kernel@lists.infradead.org; Fri, 12 Apr 2024 08:22:37 +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 16402339; Fri, 12 Apr 2024 01:22:58 -0700 (PDT) Received: from [192.168.1.100] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 069173F6C4; Fri, 12 Apr 2024 01:22:26 -0700 (PDT) Message-ID: <7f5c32dd-edc6-4b53-9cdd-780756f5536c@arm.com> Date: Fri, 12 Apr 2024 09:22:25 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] perf test: Increase buffer size for Coresight basic tests To: Anshuman Khandual , linux-perf-users@vger.kernel.org Cc: Mike Leach , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20240326113749.257250-1-james.clark@arm.com> <5a4023aa-af9b-48d2-84f3-a0b9b30dc54e@arm.com> Content-Language: en-US From: James Clark In-Reply-To: <5a4023aa-af9b-48d2-84f3-a0b9b30dc54e@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240412_012234_708455_6B127C4A X-CRM114-Status: GOOD ( 21.09 ) 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 12/04/2024 08:04, Anshuman Khandual wrote: > > > On 3/26/24 17:07, James Clark wrote: >> These tests record in a mode that includes kernel trace but look for >> samples of a userspace process. This makes them sensitive to any kernel >> compilation options that increase the amount of time spent in the >> kernel. If the trace buffer is completely filled before userspace is >> reached then the test will fail. Double the buffer size to fix this. > > This is a valid concern to address, but just wondering how did we arrive > at the conclusion that doubling the buffer size i.e making that 8M will > solve the problem positively for vast number of kerne build scenarios ? > Nobody else has reported anything yet, if it happens again we can always increase it again if that is what the issue is. I had most of the kernel debugging stuff turned on like memory debugging etc, which is probably why I ran into it and 8MB fixed it for me. So I'm not sure if there is much more that could be added. >> >> The other tests in the same file aren't sensitive to this for various >> reasons, for example the iterate devices test filters by userspace >> trace only. But in order to keep coverage of all the modes, increase the >> buffer size rather than filtering by userspace for the basic tests. >> >> Fixes: d1efa4a0a696 ("perf cs-etm: Add separate decode paths for timeless and per-thread modes") >> Signed-off-by: James Clark >> --- >> tools/perf/tests/shell/test_arm_coresight.sh | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/tools/perf/tests/shell/test_arm_coresight.sh b/tools/perf/tests/shell/test_arm_coresight.sh >> index 65dd85207125..3302ea0b9672 100755 >> --- a/tools/perf/tests/shell/test_arm_coresight.sh >> +++ b/tools/perf/tests/shell/test_arm_coresight.sh >> @@ -188,7 +188,7 @@ arm_cs_etm_snapshot_test() { >> >> arm_cs_etm_basic_test() { >> echo "Recording trace with '$*'" >> - perf record -o ${perfdata} "$@" -- ls > /dev/null 2>&1 >> + perf record -o ${perfdata} "$@" -m,8M -- ls > /dev/null 2>&1 >> >> perf_script_branch_samples ls && >> perf_report_branch_samples ls && _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel