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 07F0E212D83; Fri, 10 Jan 2025 16:22:59 +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=1736526180; cv=none; b=iLa1u1LQZ+NVgYlMZnXCexFrDrAOe348bTVFksUGktfcALkzwN+IUFd+GeKLH+CoPqcw58F+de6f7rAGPdozIhWLKMAP64vzRpiGwENYUvaovfLwhvRQiKxOEMRU0I18ubfYwYhRp2niow1JGQCKgivW+jSx+jkxCgiavicNp0g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736526180; c=relaxed/simple; bh=mQgh00oTBEnPK3eaiUyErqe8gGMKiHL5sXNk/n6ICaY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=msoPTU2NIoE74TMenAUWjTfevcVuXbXnoVhXl8FIY+fUBaNb8SRKSDxi7Pen++p2mB07tfXsrMn3MyQAgfQ2yKhoMzeRwkDqQxgN+ldZIWnvOa67H2FXZvWK775sC/wwKmCgEOwI/pcpb9+AmtRqZqR5Z9inBmxnLYmpwgOOgd4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=EGZU3Ef8; 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="EGZU3Ef8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC202C4CED6; Fri, 10 Jan 2025 16:22:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736526179; bh=mQgh00oTBEnPK3eaiUyErqe8gGMKiHL5sXNk/n6ICaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EGZU3Ef8D33bvTFUX/Tu2lXX4npAID97EObM21P4W+vsfHcYTVH9Qt4o+18iAeWc7 7+8up9z5xJj1tOzhINprHuhW8DGO8CaHO/utbP6vAj4NEuN2vMKZ5/iuud5yB8smDO +sY1QsydT5KVI4C839eN1K91nD6/amLZKnmkKRbNSIzIJfpDdFn7CkhdH8u+LDO2/j HyxY9Yejs1Y/1M1nZmZ2JdYd5RFQS4OQq69FcIkSa3Q1s30RYKw6KaDE8OxMwNgWgb o+NWQQi/txTHozc/9RXdJeXpnJlluskdVyd+LTSLhzvdRzd3oE2hEkGoOz9RGi//Xi lVT8XHiPC1bPA== From: Will Deacon To: 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, acme@kernel.org, James Clark Cc: catalin.marinas@arm.com, kernel-team@android.com, Will Deacon , 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 Date: Fri, 10 Jan 2025 16:22:48 +0000 Message-Id: <173652065683.3245172.11665292685923367751.b4-ty@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20250108142904.401139-1-james.clark@linaro.org> References: <20250108142904.401139-1-james.clark@linaro.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit 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! [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