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=1793156440; b=kfPUL2YZqHlYe/EhpDQuP9xJ75hTc8ES0GYiPg+v6ZCk60SfWewQLU5V3wrmQR3CgPXm fz6tLBs63rO/0oApEBO/EBT3LLXpcQNU62NJM1M41XGSgpa4bKaZ0FGhmozR8sobkXMG3 QU1VBc+y3EzNwrn0bLnyjeyoAqgeKm8sgWVNTYBJXz/aVrdfvW2ld12lKn1nBnEHsrVMP NaQriW67uumN69129tjo3Sstp5Os2sqe0z+N/U6gqsRyQohBTPomdEgYxD/a8EN31IMY0 72D8bPiXxciwXSVCQ5L0HylTKzkafqIKiVuYQXPv7hltsHT70pJKnPIB89sQeMAVaiQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793156440; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=3gM60uQFA1cVB45kngf04dg/qUWK7eBZRDClemfM4Jc=; b=ya7U0k8gwuYIsvK+qHB3owWCARWLO7W+NjknHlbjkbUgQFH0B36GGrZaLvwPngCTGpXI mB2ivn14aiyav6p2Wc58PWei3lK8RgpA2Ujg0sdiBlS4YQLH8veFGCRoqUKkC5+qEBk31 BZ+70DRErN1JibGsn8qQpwwLDoYN5F9tTy9mDJ8OzKDBWnjAAB5kwdqgx0du+fGjaIWQn DjjAHMT7ckbzKg+H8vT8YClA0W483K/kvflgGgl58/JyRhS8+8pSE/Yzzaep9aecnJ+Qm 50xlhuuj5xC4XK8db0HIsQB7iD3kfLI9VlptTHwKl7m67wwCrLD/CfZNY9xlJPMVGVg== 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=HdF3SfkT; 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 955C1606A31E for ; Wed, 28 Oct 2026 03:00:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=HdF3SfkT Received: by smtp.kernel.org (Postfix) with ESMTPSA id D27231F01825; Wed, 28 Oct 2026 03:00:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793156440; bh=3gM60uQFA1cVB45kngf04dg/qUWK7eBZRDClemfM4Jc=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=HdF3SfkTAZBS6eDfwy9MyJAXipLBhLSYymkig6pRidCME1eUcrBFYKB2TGiRAM+xa VvnFwARBXE6iWL9gpPtC1q1Evg7NqBsUQEzJbvHzA/56l7bFnyol8NFMwLBL+ymKaN W+cDElOnCRJfIsmSWDU5noB4zRAqFZbw9aeuvWk0XlzxePArv56TVIIM4n1UH6ydg/ f8aOP5vjtNIF+9E8tDgntA9inlu+V/UClvLrNpkiq7RI+SZxyG02OxgMa5GvgfFja2 0ei/26oMVqC/u+0QXRxWx7lax5mH+HOWXEY6XUipp8e/X7U3v48P+sTvNLQBYalqIf PxFIyo+Kgp4mA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v6 09/14] ALSA: virtio: prioritize staged capture period work Reply-To: sashiko-reviews@lists.linux.dev To: "Joonho Lee" Cc: virtualization@lists.linux.dev, "Michael S. Tsirkin" , "Eugenio Perez" In-Reply-To: <20261028025317.92450-10-mynameisjune111@gmail.com> References: <20261028025317.92450-1-mynameisjune111@gmail.com> <20261028025317.92450-10-mynameisjune111@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 28 Oct 2026 03:00:39 +0000 X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > CPU contention can delay staged capture period notifications while RX > completions continue filling the unread ring. In a two-vCPU VZ guest with > 16 nice-0 CPU workers, the ACK-fixed baseline stopped with ring_capacity > and EPIPE in three runs, after 11.74, 30.77 and 30.33 seconds of audio. >=20 > Route staged capture period work through system_highpri_wq with a common > helper at all ten producers, including ACK errors and self-requeue. Keep > playback and non-staged streams on the normal workqueue. Initialization, > cancellation, buffer geometry and capture accounting remain unchanged. >=20 > With the same kernel, input, geometry and userspace priority, the candida= te > completed three 70-second captures and immediate reopens. Its maximum > matched queue-to-start delay was 20.366 ms, versus 108.112 ms in the first > baseline failure. The other baseline failures had pending work without > matching execution, so matched-only statistics do not bound that delay. >=20 > Reader scheduling delays were also present. Both arms passed a separate > nice -10 reader control, and host load varied between runs. These results > support the change for the tested workload without isolating a kernel-only > cause or guaranteeing lossless capture under arbitrary CPU load. > KASAN/lockdep QEMU regressions passed with the unchanged candidate source. >=20 > This follows the staged ACK fix and pending VZ capture support. The > introducing staged-capture patch has no upstream Fixes commit ID yet. >=20 > Link: https://lore.kernel.org/all/rfc-v2-vz-capture-compat-1.b9ab4c1540dc= 4691@gmail.com/ > Assisted-by: LLM > Signed-off-by: Joonho Lee Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261028025317.9245= 0-1-mynameisjune111@gmail.com?part=3D9