From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.3]) (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 3D4F3503BEF; Wed, 30 Sep 2026 15:39:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.3 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790782754; cv=none; b=szhQwlQF4QC5WC0ZQavPSIoqD9odYHRmvJT7CRhlKzym6zbEzkNM1pK8KXyYRyftzA6koujFoyVOZBRELLCdriEX2JRY/YV2ewoVQM+QNqNJ86KPNdthvmb8Y9HCIYow4k84jCw4QpNxMt2lNXf+hoZsEyG+QUYppPasDRNjyMU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790782754; c=relaxed/simple; bh=lFX3KZrfU92MnwavGd458xUvv9N7aTb4w8OPb37E7w4=; h=Message-ID:From:To:Cc:Subject:Date:In-Reply-To:References; b=NWh73ffISGVQZqLK8H75CRXUY2jKw4NDzcw3IvY5mB9oz6dIRJtAVyCn+CmJQF71YDDCwfWSNX2W/eN4P3+9oMl7WetQB8kdi6AawIRr5FeRIXskt2mVUuQSMtVBef1uX06sss/Y2/7BlHPjACgJ0EdJkItKAAfHB9K3rhMXDlw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=c8oViUrZ; arc=none smtp.client-ip=220.197.31.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="c8oViUrZ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Message-ID:From:To:Subject:Date; bh=lFX3KZrfU92Mnwa vGd458xUvv9N7aTb4w8OPb37E7w4=; b=c8oViUrZb745itfq7fMVxefKZ+XVeLl 78tvnQ9DmI6OjNiChVYcOPztcQyErfVR+fT6XeUboaHZ+TgHiqrSpGgCvOi9ElMu fzdl6mNB/tm+KtoYC7UzT/mHG9qSV+iKP994uS2TlM5Jn1r/8o3TPmJGPsll8u1e SRe/DAkwrgfo= Received: from localhost (unknown []) by gzga-smtp-mtada-g1-2 (Coremail) with SMTP id _____wD3xwClLL1qzuoqBw--.14516S2; Wed, 30 Sep 2026 23:37:10 +0800 (CST) Message-ID: <68e1d1e0cdfc633520a6593fdcdb3b72.sh_def@163.com> From: Hui Su To: sched-ext@lists.linux.dev Cc: tj@kernel.org, void@manifault.com, arighi@nvidia.com, changwoo@igalia.com, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, kprateek.nayak@amd.com, linux-kernel@vger.kernel.org, Hui Su , stable@vger.kernel.org Subject: Re: [PATCH] sched_ext: Hold DSQ refs for deferred reenqueues Date: Thu, 01 Oct 2026 00:20:49 +0900 In-Reply-To: <20260930143443.2862150-1-sh_def@163.com> References: <20260930143443.2862150-1-sh_def@163.com> X-CM-TRANSID:_____wD3xwClLL1qzuoqBw--.14516S2 X-Coremail-Antispam: 1Uf129KBjDUn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7v73 VFW2AGmfu7bjvjm3AaLaJ3UbIYCTnIWIevJa73UjIFyTuYvjTRRuWlUUUUU X-CM-SenderInfo: xvkbvvri6rljoofrz/xtbCwgY+nWq9LKZoPgAA3s Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Please disregard this posting. This was intended to be v2, but I accidentally omitted the version tag. I am preparing v3 to address the review feedback. In particular, it will serialize exit_dsq() with deferred detach/reference acquisition using deferred_reenq_lock, and keep final DSQ reclamation out of the deferred path while the rq raw spinlock is held. The revised design keeps a single DSQ refcount and the existing rcu_head, without polling the refcount from repeated RCU callbacks. I will post v3 after revalidation. Sorry for the confusion.