From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794377910; b=5Tz7xduSvZf5Om3CGa3vbtE8zripCv/fI5AGRGDu/aSVveh6MowmEnWOQQy8WRS11MtJ a+EkTHCTkDght1NUXEgqUzIhkDbsFdrh0u2XcgdmcrrHi7+7aq+q0Mq01cBimyRx+bsc/ c17XGGVjkBclAsnAk315NICCpjedDCaHljZ9ztkxsly6wcLc/e5YjB4E4myNFc5PH8RGU pUabzVYJW8WF0SLx+2NtPGappfQxBcC4kmIy94wXR6DsGhpEkZw2J54YBqvGf5KPqtQub IZCuBA5J6e5FRnKDEqNm4x0LJb3vMv3e0mQvhX15FHhnN2LX7didG0nX7aqSvHNWwxQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794377910; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=VKu2xHEkhwK9Kq4tiWZRGgYWUPgmWjGSDblVBQuCnEM=; b=BND80fV7NT+4KGuVGYUnHy2DvM1gusiPSGlAjkq07wU7SZZmORTm9Nmd2pTgoEGic2bH YDIVwCCACw4SDtHrdZIPvYOJlLH7Uk0QcdZ5cHzJWlrGKPrSsnfYRpxrPwXqfsuLYjWMU kjj8ZxJ+HjrAs9GJBrRmBwkahzlWhKqDWvXjAWGNZdoQnWaeH5y1uD75m3nOO14nEVi90 BkAT7Nevv8xQMKQFCOM92MQhJDJO1SjWthzT+caUhAGJP/2OrH5qqpXsY7NzBMAWz3WCg 3YGicKU5nX/2IBi+B1PF0UgR/HUvJDHRxntMDYzspCjsUYFeDuJKZ5cbWB0zJPNcorw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ToIrRYi6; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6980A606A33B for ; Wed, 11 Nov 2026 06:18:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ToIrRYi6 Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF76B1F00A05; Wed, 11 Nov 2026 06:18:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794377910; bh=VKu2xHEkhwK9Kq4tiWZRGgYWUPgmWjGSDblVBQuCnEM=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=ToIrRYi6xbymw1BLNxYoQZe5Nzb70MGxzuqwzFhgLL11Xxs1uF4RLcN51emN48qu5 8ONL5dE4CMIT9QWxeY8ZmAs8rzI03DfoN3eQ+vrjwB4fjH1gPl2OnwfEKXeaCAWyU4 KPZJrPKicowzBlPgbFXrLAcaOXfEdJ9EZ1GpbtzJORb7B6Do0VAkU+PVrapwj5OxpW f5wfkHarkKKklWZqYKYiLlHqnptyLV7LkoxBvaqU5JSlXFXr6Kd5KMritIYLTLNjhw A7lNiE6GLFZkn0z2XvjOCewY8dkRCEVQ+fQknd5T35n1Rt7DKT5Laf2FAd0VNKVNuj xbRDXBtpBbRvw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v2] perf stat: Count kernel events in a group led by a tool event Reply-To: sashiko-reviews@lists.linux.dev To: "Hang Zhengyang" Cc: linux-perf-users@vger.kernel.org In-Reply-To: <20261111-tool-pmu-leader-v2-1-3faa0fb98c51@gmail.com> References: <20261111-tool-pmu-leader-v2-1-3faa0fb98c51@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 11 Nov 2026 06:18:29 +0000 X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Hang Zhengyang >=20 > A tool event like user_time has no perf event in the kernel, but > get_group_fd() still passes its fd, the /proc/stat fd, as the group_fd > of the members. The kernel rejects each member with EBADF and nothing > is counted: >=20 > $ perf stat -a -e '{user_time,cycles,instructions}' -- sleep 0.05 > 0 user_time > cycles > instructions >=20 > Open the members with group_fd =3D -1, as the enable/disable code already > assumes. They are then on their own, so read them without > PERF_FORMAT_GROUP and open them disabled like a leader, so that -D, > --control and enable_on_exec still apply. Keep reporting a broken > group when the leader failed to open. >=20 > $ perf stat -a -e '{user_time,cycles,instructions}' -- sleep 0.05 > 0 user_time > 38257394 cycles > 21228043 instructions >=20 > The kernel events in such a group are no longer scheduled together. >=20 > Fixes: 6828d6929b76 ("perf evsel: Refactor tool events") > Assisted-by: Claude:claude-opus-5-5 > Signed-off-by: Hang Zhengyang Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261111-tool-pmu-l= eader-v2-1-3faa0fb98c51@gmail.com?part=3D1