From nobody Mon Feb 9 09:36:43 2026 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 13E70EE14C3 for ; Thu, 7 Sep 2023 00:43:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245015AbjIGAnY (ORCPT ); Wed, 6 Sep 2023 20:43:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57552 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241271AbjIGAnW (ORCPT ); Wed, 6 Sep 2023 20:43:22 -0400 Received: from out30-119.freemail.mail.aliyun.com (out30-119.freemail.mail.aliyun.com [115.124.30.119]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ECEAB172E; Wed, 6 Sep 2023 17:43:17 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R131e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=xueshuai@linux.alibaba.com;NM=1;PH=DS;RN=16;SR=0;TI=SMTPD_---0VrV7FoD_1694047394; Received: from localhost.localdomain(mailfrom:xueshuai@linux.alibaba.com fp:SMTPD_---0VrV7FoD_1694047394) by smtp.aliyun-inc.com; Thu, 07 Sep 2023 08:43:15 +0800 From: Shuai Xue To: alexander.shishkin@linux.intel.com, peterz@infradead.org, james.clark@arm.com, leo.yan@linaro.org Cc: mingo@redhat.com, baolin.wang@linux.alibaba.com, acme@kernel.org, mark.rutland@arm.com, jolsa@kernel.org, namhyung@kernel.org, irogers@google.com, adrian.hunter@intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, nathan@kernel.org, bpf@vger.kernel.org Subject: [PATCH v5 2/2] perf record: Update docs regarding the maximum limitation of AUX area Date: Thu, 7 Sep 2023 08:43:08 +0800 Message-Id: <20230907004308.25874-3-xueshuai@linux.alibaba.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230907004308.25874-1-xueshuai@linux.alibaba.com> References: <20230907004308.25874-1-xueshuai@linux.alibaba.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The maximum AUX area is limited by the page size of the system. Update the documentation to reflect this. Signed-off-by: Shuai Xue --- tools/perf/Documentation/perf-record.txt | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Document= ation/perf-record.txt index 680396c56bd1..dfc322d6f1f1 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -292,6 +292,17 @@ OPTIONS Also, by adding a comma, the number of mmap pages for AUX area tracing can be specified. =20 + The maximum AUX area is limited by the maximum physically contiguous + memory allocated from slab/slub. It can be calculated with following + formula: + + PAGE_SIZE << MAX_ORDER + ( ---------------------- ) * PAGE_SIZE + sizeof(page_pointer) + + For example with 4K pages and MAX_ORDER=3D10 configured, the maximum AUX + area is 2GiB. + -g:: Enables call-graph (stack chain/backtrace) recording for both kernel space and user space. --=20 2.39.3