From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D25321E49F; Mon, 30 Sep 2024 19:15:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727723727; cv=none; b=URxXEt02rqtcnLLyDST8TFuMmBAwex4Rg3Wwr0l9FWyoU+3OZ21YaTcN4f8cV+vMMwsv+DgWnI8TJEkN0CoiKTy0Tj1uNqFhLW02dJtBieahBpkl3dLlJ03e0ISZtctUIFIA3cZ92mIJfBATtR3UCFRpOhHgQPjJwfB2C8NrLj8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727723727; c=relaxed/simple; bh=82nz+5A7EjVURRYOQrzWWLgwpl58/Y/kvPa3pBGW5P4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GACLJZKyE+62PS91sKkDzH1grcA9Dq1fODQoROb4/rNi86XC0pAFIkcXN6bzm3g/1rYYeYwYzUQ33OVKpeQnfShvAif0dhxjTES8q6NXvpfanOuFHFvSCmEKT5TmVZIYmcPmImJzBPhj9ryieqEM+5aeC6/DFZn4GU+R1Go4U2A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2gXT4V9R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="2gXT4V9R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F7ABC4CEC7; Mon, 30 Sep 2024 19:15:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1727723726; bh=82nz+5A7EjVURRYOQrzWWLgwpl58/Y/kvPa3pBGW5P4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=2gXT4V9RudpeiG0lP0J4rt+veiwdjhDXlXzRvQ1iPlIIx+2egAYE8Ekr8odR4Xflv vrrSQwrQjsAnwuuxrBath5HfNPfG/NCedYamf0QjpngVIUZqIGObXk0zvkR9BDlwDl ap3xSwjBkZ4MRNJm2I79xdGa0iy4sgEnm0T+ywp8= Date: Mon, 30 Sep 2024 21:15:23 +0200 From: Greg KH To: Felix Moessbauer Cc: axboe@kernel.dk, stable@vger.kernel.org, asml.silence@gmail.com, linux-kernel@vger.kernel.org, io-uring@vger.kernel.org, cgroups@vger.kernel.org, dqminh@cloudflare.com, longman@redhat.com, adriaan.schmidt@siemens.com, florian.bezdeka@siemens.com Subject: Re: [PATCH 6.1 0/2] io_uring/io-wq: respect cgroup cpusets Message-ID: <2024093053-gradient-errant-4f54@gregkh> References: <20240911162316.516725-1-felix.moessbauer@siemens.com> Precedence: bulk X-Mailing-List: io-uring@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: <20240911162316.516725-1-felix.moessbauer@siemens.com> On Wed, Sep 11, 2024 at 06:23:14PM +0200, Felix Moessbauer wrote: > Hi, > > as discussed in [1], this is a manual backport of the remaining two > patches to let the io worker threads respect the affinites defined by > the cgroup of the process. > > In 6.1 one worker is created per NUMA node, while in da64d6db3bd3 > ("io_uring: One wqe per wq") this is changed to only have a single worker. > As this patch is pretty invasive, Jens and me agreed to not backport it. > > Instead we now limit the workers cpuset to the cpus that are in the > intersection between what the cgroup allows and what the NUMA node has. > This leaves the question what to do in case the intersection is empty: > To be backwarts compatible, we allow this case, but restrict the cpumask > of the poller to the cpuset defined by the cgroup. We further believe > this is a reasonable decision, as da64d6db3bd3 drops the NUMA awareness > anyways. > > [1] https://lore.kernel.org/lkml/ec01745a-b102-4f6e-abc9-abd636d36319@kernel.dk Why was neither of these actually tagged for inclusion in a stable tree? Why just 6.1.y? Please submit them for all relevent kernel versions. thanks, greg k-h