From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 08C1946F4A7 for ; Fri, 2 Oct 2026 09:13:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790932393; cv=none; b=YgxbQptnBvB7lr3WTOetS+4O16lV3jGaTPpmHHn6c7rUymNK7H5tM6FOezdQSyOutl483LmjUkcpQbg+pjCkyFrWldlriqHp9CsVhhLgZSR7WyaSYRczXeAtX+aHtKB70d7Y7MTWcQhMO5UY8S+15WSE2X6XrViE4/OJq8cyqOE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790932393; c=relaxed/simple; bh=xkQbA3fbx1lWsHMqg/ik/x5I8aXeEjCT/utoyuJSrEM=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=LWGp1xfqH4ICMS37vo/GTNNmnJXgeObTl9hdf4BdYuR6seBL3m+C01DDOiiZ1QDHPLZAkflTWa0Ek2ckLct6ehQiSrG4pOfwEKHWa6Q0yVROUTwQIhqXdfAGW30PX0mcZfNl6icNAUat3N4JrTBBsqcMXEJrPpAq69XvjM8r5oM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WQ9kHaLk; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WQ9kHaLk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C64211F00898; Fri, 2 Oct 2026 09:13:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790932390; bh=IoBmWjo/Bn2o/Cf3Ueb78V9fCtOeycOiwvfrv/swgQQ=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=WQ9kHaLkngUjPdAjNfTOVO5hdrlCK3yC4gNnGuNf1pVwECXzqy/nKceDTlSrZVs8d bKw5TK96NpajwezD9/RemWEHemAJZul/KjuajsZ4BfIYQaogDFPG3Oxrpy2JUJjGBJ EnEKlkRDD4LKxFdulX/lb3f/t6phaNaOjK3sdB+eYt3ULdmd/lTLyag35Fqe27/S0g wB+d64otKA+ZZVy+zLNJKA5jaICwrBT5ZfFUmpa85k1qFlq+jn0UWsmF3Bfuua/561 FKeXyi2jF+eMbFefJAV7jM+AH7mpdnn/ugRc6q/wE4Bo7o2WdpjJGVeQOT04VvLsTU 6W9Z+weOkHeSQ== From: sashiko-bot@kernel.org Subject: Re: [PATCH v7 9/9] perf test: Add false_sharing workload exhibiting cross-CPU false sharing Reply-To: sashiko-reviews@lists.linux.dev To: "Arnaldo Carvalho de Melo" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261001185400.2754753-10-acme@kernel.org> References: <20261001185400.2754753-1-acme@kernel.org> <20261001185400.2754753-10-acme@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 02 Oct 2026 09:13:10 +0000 Message-Id: <20261002091310.C64211F00898@smtp.kernel.org> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: > From: Arnaldo Carvalho de Melo >=20 > Add a 'perf test -w false_sharing' workload that hammers one shared > struct from several CPUs, shaped as a TCP connection: a read-mostly > identity (five-tuple) shares a cacheline with per-packet rx counters > (the false-sharing line), a second line has packet-path private tx and > congestion control counters, and a third the connection config. >=20 > The packet path runs in the main thread and up to four lookup threads > sum the five-tuple and pull the config, reading one volatile shared > instance directly so the accesses are PC-relative and resolvable by the > data type profiler. >=20 > Data type profiling of the workload with cacheline info: >=20 > [ ... ] > 0.00% 0.01% struct folio +0x34 (_refcount.counter) > 0.00% 0.00% struct folio +0x18 (mapping) >=20 > Assisted-by: LLM > Signed-off-by: Arnaldo Carvalho de Melo Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261001185400.2754= 753-1-acme@kernel.org?part=3D9