From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F18F023D289 for ; Thu, 30 Oct 2025 15:42:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761838962; cv=none; b=Vfmc8aWT2qSUlH4COcDfe7dXLPej22JSuKGf0FA2YhpK9JLfT7jE/GjiEPT4dLFZLaDe50fhrZ/wtr0xOm2gDVFG/0OxaU7UG1pl3wj5fz2kNSjO/s3Y46OfXLGzVGsMiw/3cDVShC+CT3LLfSqKkpdYauc799rgAfXBxMvFwCo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761838962; c=relaxed/simple; bh=eSpRBIQFx2Fm+8Fj1pvi3qgMO08RKixTmOFPmRvr3QQ=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=DZA8c+9dJTef/NmYckl0emlnpBm5WxS6NqtKrT5TF5rwL0HhMvle+32t8ZznlaQcmNxLDRvb5xKCvHJAihRryplo/kqMJrFL+sXKolIs46CfwpixT0xCsLqzZrhbXuCQpAt1/rYur7azIqVmkle7/SoDexbiL8aG2M5Eo2Xw/MI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=eZMiwTie; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="eZMiwTie" Received: from localhost (unknown [20.191.74.188]) by linux.microsoft.com (Postfix) with ESMTPSA id C78EF211D8D7; Thu, 30 Oct 2025 08:42:39 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C78EF211D8D7 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1761838960; bh=ysPZrd0ypANag9xbIeXXFA7XUkCdWdZgyvKIS/nwA/o=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=eZMiwTie9BYM8QHnCmOHnVQpzEmwXnPppJ/+gxLd1tL0NDnIZjWlBlA14zBEM2yYK fzuE0NoPqBtH+HZs8xBWB9n3TmDMCnP2gjYQ+slASQFirdWKoM+xhrUcbDlbjUl/16 qlLNRUk8/3HFn6Btj/ZyVu8Xbt3bAZshCUSxpru4= Date: Thu, 30 Oct 2025 08:42:38 -0700 From: Jacob Pan To: linux-kernel@vger.kernel.org, "iommu@lists.linux.dev" , Will Deacon , Joerg Roedel , Mostafa Saleh , Jason Gunthorpe , Robin Murphy , Nicolin Chen Cc: Zhang Yu , Jean Philippe-Brucker , Alexander Grest Subject: Re: [PATCH v2 0/2] SMMU v3 CMDQ fix and improvement Message-ID: <20251030084238.00003fbf@linux.microsoft.com> In-Reply-To: <20251020224353.1408-1-jacob.pan@linux.microsoft.com> References: <20251020224353.1408-1-jacob.pan@linux.microsoft.com> Organization: LSG X-Mailer: Claws Mail 3.21.0 (GTK+ 2.24.33; x86_64-w64-mingw32) 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-Transfer-Encoding: 7bit Hi Will, Just a gentle reminder, appreciated. @Nicolin, were you able to evaluate these? By the way, I incorporated your review comments in v2, except for extracting the function arm_smmu_cmdq_poll_until_enough_space(), primarily due to concerns with the IRQ flags. Thanks, Jacob On Mon, 20 Oct 2025 15:43:51 -0700 Jacob Pan wrote: > Hi Will et al, > > These two patches are derived from testing SMMU driver with smaller > CMDQ sizes where we see soft lockups. > > This happens on HyperV emulated SMMU v3 as well as baremetal ARM > servers with artificially reduced queue size and microbenchmark to > stress test concurrency. > > Thanks, > > Jacob > > Alexander Grest (1): > iommu/arm-smmu-v3: Improve CMDQ lock fairness and efficiency > > Jacob Pan (1): > iommu/arm-smmu-v3: Fix CMDQ timeout warning > > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 97 > ++++++++++----------- 1 file changed, 47 insertions(+), 50 > deletions(-) >