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 82BEE1E4A2; Thu, 7 Mar 2024 18:50:22 +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=1709837422; cv=none; b=KVdMceSq5R5Td1nUvUJ5qc4D4Qo/CbNSsNtCnvzoHIZa8ePv/8i7j1J0ZhsJopL+bBkwzC9+sK1YWAyOjAPYHizGHBTFbJu/GZdulC0uv0VbNdC/TUkez+B34ejHQFzqB0agq/wJDRaEXCcRWLA8iE+RLW3cc1Lrq6aOCO0fZ+Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709837422; c=relaxed/simple; bh=Oui1MW119tBegORPmVHwUMz4AAtqfEqlY9x5E6G59XE=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lJ+hSeolhVGHq6hMPi71qNIxQLmOW2azwiTF39/zTf2m6+jdEhGLAym9ooC2e0AT4YWBe59PsylRM5K7gMG6MgzHHEiQfY2pqm+smqXWRhMQx4HSJbgWhbxZBpKliB49ETYIMQbbkbXMWK0kEtYqFnIJr2l162Cx6OnPXQ9QS04= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0F7CBC433C7; Thu, 7 Mar 2024 18:50:20 +0000 (UTC) Date: Thu, 7 Mar 2024 13:52:15 -0500 From: Steven Rostedt To: Mark Rutland Cc: Joel Fernandes , paulmck@kernel.org, Network Development , LKML , rcu@vger.kernel.org, kernel-team Subject: Re: [PATCH] net: raise RCU qs after each threaded NAPI poll Message-ID: <20240307135215.7ba88d83@gandalf.local.home> In-Reply-To: References: <55900c6a-f181-4c5c-8de2-bca640c4af3e@paulmck-laptop> <10FC3F5F-AA33-4F81-9EB6-87EB2D41F3EE@joelfernandes.org> <99b2ccae-07f6-4350-9c55-25ec7ae065c0@paulmck-laptop> X-Mailer: Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 7 Mar 2024 16:57:33 +0000 Mark Rutland wrote: > * Use rcu_tasks_trace to synchronize updates? Yes. I think I wanted both. The above to make sure it covers all cases where something could be preempted, and a case for those covered when RCU isn't watching (which always has preemption disabled). My mistake was I thought synchronize_rcu_tasks_rude() did both. But I just found out recently that it is not a superset of synchronize_rcu_tasks(). But it really needs it in every location that synchronize_rcu_tasks_rude() is called. -- Steve