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 B7446342C80 for ; Mon, 3 Aug 2026 16:58:03 +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=1785776284; cv=none; b=u5PRC+LjSdnEdeKznB0QSLdadOfW2f+bW3cfVUGw4JM0sX/MSM13YzGwPfslM1bRdfnC+kQpzMB/l0x06NHx7qP0cZqeIAR9j249KlhSLpDRkHWlDw8zjubswBmv6ikS5IsGPjMfGByHxlZ8r0Wa2cDZx181X4sq3cHFPHKb6mE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785776284; c=relaxed/simple; bh=Kxu5G6v84TS4xD3TVBVQPu71pUS1ZMqwT9e/1kQoKEg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gjJLvqaMIVyldwZoncOXKmRZyxL6CQstZT2VIGqR9rxFZoynDeGQGboDIwHvuZdwdZ9NYZjNwfUqsrZbpyes0BZb6+SRu1R6Z/HGFcwG0wdsNm+7t2tLgyVwN+ilGZKA6JqVKERq2sgDQ1j2AA3Wa3TjW27WudYscoDHdWL4BjU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cRXRpFbV; 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="cRXRpFbV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 223A71F000E9; Mon, 3 Aug 2026 16:58:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785776283; bh=feWIMZ4HuIb1AqrbGvsafVLWt+6wgXZepeNkqHPVbak=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=cRXRpFbV0B9J0QMmbFEYhzJ/C59DuZX/eeHZbM+rudqdt+5HwMwBVaYA1Fm16fqra tS2mKqsiaLXAyG+FbyG1VG84PYhQ9edBPlzSbfcQ/gfLyFyanVx2gMJVEltFOTE6/u Mp0an11mZlWstBFxoRWPKQlDD1coKquepU4UicAVEaao1adsu6tGzotCBIvmf8P4Xy 8CgSMR2zozY12KpCHx7t0c0n+HGo2m4FGzZrWKI3FEhpXK1XTUhZEicRVlZZfgF95y AAzMSW+Qt7XhsxsWr4YRGqcdWvlRZT2kFfAvn7uSAcctrUCAdH5woGntIeroawptWG my1UUyJ4JlWxQ== Date: Mon, 3 Aug 2026 06:58:02 -1000 From: Tejun Heo To: Breno Leitao Cc: Lai Jiangshan , linux-kernel@vger.kernel.org, kernel-team@meta.com, marco.crivellari@suse.com Subject: Re: [PATCH 5/6] workqueue: add a per-cpu backend for unbound pwqs Message-ID: References: <20260731-wq-pool-refactor-v1-0-8eaf71cdab5f@debian.org> <20260731-wq-pool-refactor-v1-5-8eaf71cdab5f@debian.org> 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=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Aug 03, 2026 at 09:35:16AM -0700, Breno Leitao wrote: > a) There is one workqueue implementation -- what is today the unbound one -- > and percpu becomes one of its affinity settings rather than a separate > type. The unbound_* helper names get renamed/removed once they stop > being unbound-specific. So, `alloc_unbound_pwq()` becomes > `alloc_pwq` and handle both cases. > > b) There is one pwq path, and alloc_and_link_percpu_pwqs() goes away. > > c) Which pool backs a pwq becomes a property of the attrs, resolved in > alloc_unbound_pwq(), which hands out either the static percpu pool for > that CPU or a hashed unbound one. > > d) Both pool types stay -- concurrency management only exists on the percpu > ones -- so what gets merged is the machinery, not the pools. > > e) this ugly __WQ_PERCPU_POOLS goes away, WQ_PERCPU carries the > intent, and the unbound path handles WQ_PERCPU directly. WQ_PERCPU > and WQ_UNBOUND stop being mutually exclusive types and become > a choice of backing, so the exclusivity check in alloc_workqueue() > changes meaning or goes away. Yeah, this makes sense to me. Thanks. -- tejun