From nobody Fri Dec 19 17:17:58 2025 Received: from mail-wr1-f46.google.com (mail-wr1-f46.google.com [209.85.221.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E3B463469EC for ; Thu, 6 Nov 2025 16:08:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.46 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762445305; cv=none; b=Xn64tGYbZywbjo3ICVibKWUCCZBuyd39EDFKzrVemgzHMKrf4PEQ6/fgBezTAbok1H/24uQAW4gsvkpjC8ekXF4fQCbgOqeSKVSaOhYZUMi4AO8lbpTLSA4BK+eTJLNrlKF18RaCJUPEbpWH+JqFi7zSc84LfKeTogsAE1I4IOs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762445305; c=relaxed/simple; bh=xPWclQvY+EnBtUcWHuPqxyG5ICL9eKEa6h1sgDCttAs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=pY63ylwidCj4aycT7q/1u9H9aFLTE11G7tgDg7licr6Ta1ru0ve645b4DVygmmiTJZnE2vqsdjvyZ7hRq14L1k1qU0PgGuPyW4O0yeKRZ1g2yxf2uPUjjS5RumDYQbicKrX6L4Cgc/cf3+NAQN0LlkS4d+V2xAEeSWudj6xRrVw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=WzDUul+g; arc=none smtp.client-ip=209.85.221.46 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="WzDUul+g" Received: by mail-wr1-f46.google.com with SMTP id ffacd0b85a97d-421851bca51so939407f8f.1 for ; Thu, 06 Nov 2025 08:08:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1762445301; x=1763050101; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=nx1lPTEbzZHY1qdv26YxvfoI4idRJcQOTqxZM+W3Lcg=; b=WzDUul+g+w2wFmZ2zTUAvqAHNkhLnfcbNhVc4GXrKf/IQqyF/M85+h6P0RRdw67+HY Q18CaFi//xYtGsGT78VaryIwu+ecbCx14sRB6DNCGVhKtfQodVI8G+5fcpscsecH66eO ZHSH2jdWumGPWFmdHSO9y2muY/6T2O9Mer6U44B4Wyxid+uGkL9Ebggbk+69QbvXMqAU 9D0/0qzkrEzFL5OKGHHljcvoy9EoBgoJ7xgpXh4/PWPpx8K6ZxLDvwN8qlk11gLwLyVx r5nn65msZzaxw1yeYHYFBqVfKIdmJj42ft4aX1NAOFa4nNsCII7faY3V2ENDqkl2NDa3 GdYQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762445301; x=1763050101; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=nx1lPTEbzZHY1qdv26YxvfoI4idRJcQOTqxZM+W3Lcg=; b=tmjpTTX5OHn+UfxsIhKj/h0NZeVI0+Zciipdwji+kM0BEUI4WWnvBSErTdKEHDiMTH WKZN6QzZRhCN385ArUf549vNvk1IA4tjQpOL246DAicmsq4IAOVXXpo9l7yMAu3K+so7 IMb1XERFS2c9iVxRGF1Khhz2d2VvVzY7OPudBss3aE6FtO5vUQw4fybTYhqlQif0TKOb D3+LNlPfZMUR3pTFsxigjEaHVn1sP8vsGAJCXgmJFHZQ2FFnNPxKTO8MPcRV+rIGycOq xgE8nX1j6HhTy8fet2JlXNKM5K2nAcvlmlk0vTm21M4baKDE6EFXRaCfk2NwfYp4kXVs ULPQ== X-Gm-Message-State: AOJu0YzuOqfdRNU/nVr4BOOJEnfOBhjUOl3y0UuGy3BeKHfdyP6xlDYc c44eIxnskmzqH1wzioLI6noB0/6GfMXzQYb9O4o7v9Tu7aUamrjpDWW4tIgBroKp1JmtBmI8V+h 9Na74 X-Gm-Gg: ASbGncu/Tx9HHmxdh96WmU0qx3ogT9oK2cjKQbxjufKOmBH6usF5mTbjgITAGvZm9XZ sXwNdoNSF19Dkqax8mC5sYGThAi460uaPRSduyNWrmu9252jlbQTmj/eCM8/R29YUe4DUkvyiCT F8BAlUVPdugV6jclR4cOY2RMONI9UGzasR19M7BosAh/aBmXK00gs6WM0jjrL+3ny+BsCYoLOSs EuB/2ckDtDNbezZg+u6tOLVMmH+aQlGJ/Ip0p/TyMdsXByZR11D7uRM/iAtPNknWz2Gl//rSwZY 3ZD2rWJwKEQkxKmp8K3CXYCMRv4wcy7p4MB6/xCOrzT1ByzBf9BDh3pefDC98zX8mG9n6tBLg0X bLQm87/XnOYrpg45wplUdaJhZ2ZTUOSzZ40YAwnOoH/POxEN/gQz9m2LNyKm4EVmeZIPg4sDSy1 yS9qCk7U1tyVsY/bV+qiKw9kzwRQubG84cqw== X-Google-Smtp-Source: AGHT+IHrwHGLgBBhAgtrfyKEpFfxFAA7i3wIf/3/ZalE+AmFaR63fQ6Dh3eaDSrDXVqOyiQRM7ThTQ== X-Received: by 2002:a05:6000:420b:b0:400:7e60:7ee0 with SMTP id ffacd0b85a97d-429e327888emr5905151f8f.0.1762445300744; Thu, 06 Nov 2025 08:08:20 -0800 (PST) Received: from localhost.localdomain ([2a00:6d43:105:c401:e307:1a37:2e76:ce91]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-429eb4037d3sm5893097f8f.6.2025.11.06.08.08.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Nov 2025 08:08:20 -0800 (PST) From: Marco Crivellari To: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org Cc: Tejun Heo , Lai Jiangshan , Frederic Weisbecker , Sebastian Andrzej Siewior , Marco Crivellari , Michal Hocko , Damien Le Moal , Niklas Cassel Subject: [PATCH] ata: libata-sff: add WQ_PERCPU to alloc_workqueue users Date: Thu, 6 Nov 2025 17:08:13 +0100 Message-ID: <20251106160813.314932-1-marco.crivellari@suse.com> X-Mailer: git-send-email 2.51.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistency cannot be addressed without refactoring the API. alloc_workqueue() treats all queues as per-CPU by default, while unbound workqueues must opt-in via WQ_UNBOUND. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they=E2=80=99re needed= and reducing noise when CPUs are isolated. This continues the effort to refactor workqueue APIs, which began with the introduction of new workqueues and a new alloc_workqueue flag in: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") This change adds a new WQ_PERCPU flag to explicitly request alloc_workqueue() to be per-cpu when WQ_UNBOUND has not been specified. With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND), any alloc_workqueue() caller that doesn=E2=80=99t explicitly specify WQ_UNB= OUND must now use WQ_PERCPU. Once migration is complete, WQ_UNBOUND can be removed and unbound will become the implicit default. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Reviewed-by: Damien Le Moal --- drivers/ata/libata-sff.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c index 1e2a2c33cdc8..785b6e371abf 100644 --- a/drivers/ata/libata-sff.c +++ b/drivers/ata/libata-sff.c @@ -3191,7 +3191,8 @@ void ata_sff_port_init(struct ata_port *ap) =20 int __init ata_sff_init(void) { - ata_sff_wq =3D alloc_workqueue("ata_sff", WQ_MEM_RECLAIM, WQ_MAX_ACTIVE); + ata_sff_wq =3D alloc_workqueue("ata_sff", WQ_MEM_RECLAIM | WQ_PERCPU, + WQ_MAX_ACTIVE); if (!ata_sff_wq) return -ENOMEM; =20 --=20 2.51.1