From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 930D91FBBCA; Mon, 13 Jan 2025 14:45:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736779556; cv=none; b=go540K5LhMOkYZZXO5qK6g86VPOy4W78QJnh2eO0jZpWpJD77HNCxGYtAi55fyiM6RCIzgP3sc635TUdiHDjAXQQAIkYlx5wqgVO2e1VRG75nno5UsjCmfzOvveqchJeRUr9l1cK12Pp2jZKlscCbvQznwQ0ryUbJGHTrtPADXk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736779556; c=relaxed/simple; bh=4Vujzbm4kNtV5/o/KXPggv4nUMTIKxP0LOJAZ9i8Z+Q=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=p9rkQT9jd0xAaiZ03c5Vg2yzWypXSDD+A3TPPvephhS8lfo4eO2QKr9VfeFLvTHBM7EzrAfGq6xyO2/qohddZFzt0UeCLQa0O8wP6HEvB70+IfGXaHiZKmFIkqxgJ+oE+EubzhnW5p6s7BKi9MrE5APHKF+Y5u4TNPoVDFfRWGE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cjGQw4qr; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cjGQw4qr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A543CC4AF0B; Mon, 13 Jan 2025 14:45:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736779556; bh=4Vujzbm4kNtV5/o/KXPggv4nUMTIKxP0LOJAZ9i8Z+Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cjGQw4qrc+25VwrU5o7c9G3d/cR+3CwDJHhEQLzEagi/U7UsotaPFVUfY5mHihKPM ukP5fL2SRcmpEtGWyI5yFsXX8LS09ahNaQE30YcFWnTS4U6dGx3OhImPgnoSir5OL0 fSkkiFeSOy1h5QOSf2yTbdTDuVCT73Hpy4bnFcS8qSWoFm2Zkssdqb3/L9cbdcX7+q AYbcvhxZA+tV+1TqTQcGkiWDwG5SHCgshXTJj05m0o5U9yGH0jjEQkaMmK16Ic3ovU M3F6JXJRcgdrURmFSPsuUuQRuZXpOPAicnrl91k9kRkz3AgC0XIE5+EjEhwXNxXgoy Bz8YtOupu7h4Q== Date: Mon, 13 Jan 2025 11:45:52 -0300 From: Arnaldo Carvalho de Melo To: Will Deacon Cc: linux-arm-kernel@lists.infradead.org, linux-perf-users@vger.kernel.org, irogers@google.com, yeoreum.yun@arm.com, mark.rutland@arm.com, namhyung@kernel.org, James Clark , catalin.marinas@arm.com, kernel-team@android.com, robh@kernel.org, Peter Zijlstra , Ingo Molnar , Alexander Shishkin , Jiri Olsa , Adrian Hunter , "Liang, Kan" , John Garry , Mike Leach , Leo Yan , Graham Woodward , Michael Petlan , Veronika Molnarova , Thomas Richter , Athira Rajeev , linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH v3 0/5] perf: arm_spe: Add format option for discard mode Message-ID: References: <20250108142904.401139-1-james.clark@linaro.org> <173652065683.3245172.11665292685923367751.b4-ty@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <173652065683.3245172.11665292685923367751.b4-ty@kernel.org> On Fri, Jan 10, 2025 at 04:22:48PM +0000, Will Deacon wrote: > On Wed, 08 Jan 2025 14:28:55 +0000, James Clark wrote: > > Discard mode (Armv8.6) is a way to enable SPE related PMU events without > > the overhead of recording any data. Add a format option, tests and docs > > for it. > > > > In theory we could make the driver drop calls to allocate the aux buffer > > when discard mode is enabled. This would give a small memory saving, > > but I think there is potential to interfere with any tools that don't > > expect this so I left the aux allocation untouched. Even old tools that > > don't know about discard mode will be able to use it because we publish > > the format option. Not allocating the aux buffer will have to be added > > to tools which I've done in Perf. > > > > [...] > > Applied driver and docs patches to will (for-next/perf), thanks! Picked the rest and added it to perf-tools-next, Thanks, - Arnaldo > [1/5] perf: arm_spe: Add format option for discard mode > https://git.kernel.org/will/c/d28d95bc63cb > [2/5] perf docs: arm_spe: Document new discard mode > https://git.kernel.org/will/c/ba113ecad81a > > Cheers, > -- > Will > > https://fixes.arm64.dev > https://next.arm64.dev > https://will.arm64.dev