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 87CA916DECF; Wed, 12 Jun 2024 09:42:18 +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=1718185338; cv=none; b=XZTG6pnqfRRUN2haVNkQVdZV7+oAfE0Fan8noYMkFHrnAecXk9P/HBK/0nfmCPsCycwRq5f96O0to1c94ehecgPpTfhvwslMU63LxTl7ci38y9cM1eo2nM+O9VTQ7/XUUPzv6iSK6hWyDs8gZ7YfE7V0Ccwev1ihT9DX81uB2Ko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718185338; c=relaxed/simple; bh=4e+EIVhbrt7oVMReblWRn01qu1QrqTBkE9krZ/pM+Yg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lwXzIa57TGJynRLKDw9xk6dNzTHNdwCMg4rpo1DJ0P/5wBABXWpcUOicbFY2hEfZgZR2fyl8oiDoFdxW0tsbSYcUGoDIlBOiGCAAU7cJ9GT7GXpEvQZTMIwIIK2pihaO1A+X8A+T7UlklhRGyi3Gxtmf3oAxQudrS22pBfkkBeQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nt+V0wl/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nt+V0wl/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0906C4AF1A; Wed, 12 Jun 2024 09:42:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1718185338; bh=4e+EIVhbrt7oVMReblWRn01qu1QrqTBkE9krZ/pM+Yg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nt+V0wl/77MlpIcQhJQ7mCMj072ACyTYCC5zJhCDzb+sBxA/c6b0FQqah3jxNgpl6 9jv/9EZBmb2Hr7ki41tavui7nBt034mSBj1ZlJKm8zVvVMfUep41iVkwciqyi6Ihca QcAkyhAL3H9V0v84GUfsmREOpUgXWK/r+fioQgAhB/hGu2UUsoxv4MZrPFj/sZC+MO YXZstn+QUYhoXiKHeY8H12r1q9I7Pm386HpCaEnvSAejNDJd6iKiEdDQWnfaDNhelM Zr7CFn6Ve8tujWBPUPg2ctioG2pejIWJ/9TbdorUoyrRSA9VJaTYuWZ+cU2QLToxs/ u0HTbJxkm4ubA== Date: Wed, 12 Jun 2024 15:12:07 +0530 From: Neeraj Upadhyay To: "Paul E. McKenney" Cc: rcu@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org Subject: Re: [PATCH rcu 0/6] Grace-period memory-barrier adjustments for v6.11 Message-ID: <20240612094207.GA418202@neeraj.linux> References: <81f4e616-8125-4934-a8e2-fd5beae90995@paulmck-laptop> 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: <81f4e616-8125-4934-a8e2-fd5beae90995@paulmck-laptop> On Tue, Jun 04, 2024 at 03:26:46PM -0700, Paul E. McKenney wrote: > Hello! > > This series removes redundant memory barriers from the grace-period > code paths: > > 1. Remove full ordering on second EQS snapshot, courtesy of Frederic > Weisbecker. > > 2. Remove superfluous full memory barrier upon first EQS snapshot, > courtesy of Frederic Weisbecker. > > 3. rcu/exp: Remove superfluous full memory barrier upon first EQS > snapshot, courtesy of Frederic Weisbecker. > > 4. Remove full memory barrier on boot time eqs sanity check, > courtesy of Frederic Weisbecker. > > 5. Remove full memory barrier on RCU stall printout, courtesy of > Frederic Weisbecker. > > 6. rcu/exp: Remove redundant full memory barrier at the end of GP, > courtesy of Frederic Weisbecker. > Reviewed-by: Neeraj Upadhyay > Thanx, Paul > > ------------------------------------------------------------------------ > > b/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.rst | 6 +-- > b/kernel/rcu/tree.c | 2 - > b/kernel/rcu/tree_exp.h | 8 +++- > b/kernel/rcu/tree_stall.h | 4 +- > kernel/rcu/tree.c | 19 +++------- > kernel/rcu/tree_exp.h | 8 +++- > 6 files changed, 26 insertions(+), 21 deletions(-)