From nobody Sat Feb 7 11:38:14 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2C4CC20323; Mon, 12 Aug 2024 09:35:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723455318; cv=none; b=q0gxDMftDHXSSAej8imWvSfkGxX8d1tNYCucoNwJf1scMAfApRBoDvZLLOPxpaCyuyUkA0FkQO6sYe8zNdV0x+FCyQAGu6yl0EQL40gRy/lLEVjt62Dni0jrKpRBeQo3B5A83cHQk17uWFAq2WqdUhOYDkacY/2T1QMMmDFqu8w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723455318; c=relaxed/simple; bh=25iON2aOSkv1pwiu6PEitoWSc9We2+COGfPD5yyWuWw=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Vczux81D+27f1US83l/AjgTlt5XYY52oEENExCpg2Apzb8HqhvfPFl59f95/62OoysEBzHodPYivSqsWpZEbHd7nPQbrx5okw59Gvzw7pwaYoa1cbV4IMaZY4wEpwCbKiE9pLjVzOy4/CbN2I3wEK3HOVplL9NNftIecM+UYr+4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 D4192FEC; Mon, 12 Aug 2024 02:35:40 -0700 (PDT) Received: from e132581.cambridge.arm.com (e132581.arm.com [10.2.76.71]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 975E83F73B; Mon, 12 Aug 2024 02:35:13 -0700 (PDT) From: Leo Yan To: Arnaldo Carvalho de Melo , Peter Zijlstra , Ingo Molnar , Namhyung Kim , Jiri Olsa , Adrian Hunter , "Liang, Kan" , James Clark , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Leo Yan Subject: [PATCH v2] perf docs: Refine the description for the buffer size Date: Mon, 12 Aug 2024 10:34:59 +0100 Message-Id: <20240812093459.2575278-1-leo.yan@arm.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Current description for the AUX trace buffer size is misleading. When a user specifies the option '-m,512M', it represents a size value in bytes (512MiB) but not 512M pages (512M x 4KiB regard to a page of 4KiB). Make the document clear that the normal buffer and the AUX tracing buffer share the same semantics. Syncs the documents for consistent text. Signed-off-by: Leo Yan Reviewed-by: James Clark --- Changes from v1: Synced for all documents for consistent description (James) tools/perf/Documentation/perf-kvm.txt | 6 +++--- tools/perf/Documentation/perf-record.txt | 9 +++++---- tools/perf/Documentation/perf-top.txt | 4 ++-- tools/perf/Documentation/perf-trace.txt | 4 ++-- 4 files changed, 12 insertions(+), 11 deletions(-) diff --git a/tools/perf/Documentation/perf-kvm.txt b/tools/perf/Documentati= on/perf-kvm.txt index b66be66fe836..c26524d38f47 100644 --- a/tools/perf/Documentation/perf-kvm.txt +++ b/tools/perf/Documentation/perf-kvm.txt @@ -115,9 +115,9 @@ STAT LIVE OPTIONS =20 -m:: --mmap-pages=3D:: - Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. + Number of mmap data pages (must be a power of two) or size + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. =20 -a:: --all-cpus:: diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Document= ation/perf-record.txt index 41e36b4dc765..242223240a08 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -273,10 +273,11 @@ OPTIONS -m:: --mmap-pages=3D:: Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. - Also, by adding a comma, the number of mmap pages for AUX - area tracing can be specified. + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. + By adding a comma, an additional parameter with the same + semantics used for the normal mmap areas can be specified for + AUX tracing area. =20 -g:: Enables call-graph (stack chain/backtrace) recording for both diff --git a/tools/perf/Documentation/perf-top.txt b/tools/perf/Documentati= on/perf-top.txt index 667e5102075e..af3e4230c72f 100644 --- a/tools/perf/Documentation/perf-top.txt +++ b/tools/perf/Documentation/perf-top.txt @@ -83,8 +83,8 @@ Default is to monitor all CPUS. -m :: --mmap-pages=3D:: Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. =20 -p :: --pid=3D:: diff --git a/tools/perf/Documentation/perf-trace.txt b/tools/perf/Documenta= tion/perf-trace.txt index f0da8cf63e9a..6e0cc50bbc13 100644 --- a/tools/perf/Documentation/perf-trace.txt +++ b/tools/perf/Documentation/perf-trace.txt @@ -106,8 +106,8 @@ filter out the startup phase of the program, which is o= ften very different. -m:: --mmap-pages=3D:: Number of mmap data pages (must be a power of two) or size - specification with appended unit character - B/K/M/G. The - size is rounded up to have nearest pages power of two value. + specification in bytes with appended unit character - B/K/M/G. + The size is rounded up to the nearest power-of-two page value. =20 -C:: --cpu:: --=20 2.34.1