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 40B19411A12 for ; Sun, 4 Oct 2026 10:27:27 +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=1791109649; cv=none; b=iYag1avl5gnAZbFoDbBjI9EfTChPpZhMMkudXTMjiHFN1HUtag2apbHWjchWzkW6Bj5kLYZSk5JkSpd9xuBTL9r0aRhsXfQ/bikASIQpPHac2PE8XMl5Re/qRNDH+nVzIlb5hwzsF9/dTPApmv0MbH+viTFb6mRITzrViWQ0os4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791109649; c=relaxed/simple; bh=oa2emghJ9orV08SC0k+enQIYedOPezrXb52pY/ONpWk=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=Cr8ftmRKS6ylFICv/EtZnpfFv3WWzz/wv1X9/WE1IicZoOCQJNaV3igQhAm6sLRIdZpuzBgToNV9HURK4oP6BB777brBwWnZ45KpvYqMt1ZLrsqnTdE/mwA7yq7A3JjU6FRHVvTBLjboSeGC2jv5nsxAwmnwXetW0FQ3ea7jX8s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n+zcXv6T; 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="n+zcXv6T" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B678D1F0089A; Sun, 4 Oct 2026 10:27:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791109647; bh=O+vuH7TniKlk23XlP6ka+ka6R1Lzvz2TYknNPAlSUbg=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=n+zcXv6TdiFSHbQdvGEle5JLYaGkYRjQ7MWllXKTe0UIlFnHHdeL6PARGafZp+YDb 8j2n5zBB6vO8S+4qtaE6h67KYbM1bRHqzAKOXY0FAfGEsla1pz5LVg3aTr106KAhzP rA1a0PK8MjMBB3FqgjZFEdgfjbYWWznSY2vsroarllRzgiK3VMS/akacBVmMzE1efC NObR6HJvNIEUA6I/x47hSdR+idXbbM5F7EjfNKCZmCTXK/WwfvcCgp/EsxEOkEG9wc 9qdI31taH9e59R/r7O9mhMkRlP/YIk2HjRICuUH904ula9g+QlTiwsUfqSXK3ddW2Q ePIoEciyD8X0g== From: sashiko-bot@kernel.org Subject: Re: [PATCH v10 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: <20261004102133.26392-10-acme@kernel.org> References: <20261004102133.26392-1-acme@kernel.org> <20261004102133.26392-10-acme@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sun, 04 Oct 2026 10:27:27 +0000 Message-Id: <20261004102727.B678D1F0089A@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/20261004102133.2639= 2-1-acme@kernel.org?part=3D9