From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ua0-f199.google.com (mail-ua0-f199.google.com [209.85.217.199]) by kanga.kvack.org (Postfix) with ESMTP id 02C5028089F for ; Wed, 8 Feb 2017 11:25:38 -0500 (EST) Received: by mail-ua0-f199.google.com with SMTP id 96so79909781uaq.7 for ; Wed, 08 Feb 2017 08:25:37 -0800 (PST) Received: from mail-vk0-x22e.google.com (mail-vk0-x22e.google.com. [2607:f8b0:400c:c05::22e]) by mx.google.com with ESMTPS id p15si2421679vkp.82.2017.02.08.08.25.37 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 08 Feb 2017 08:25:37 -0800 (PST) Received: by mail-vk0-x22e.google.com with SMTP id t8so104550030vke.3 for ; Wed, 08 Feb 2017 08:25:37 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20170207210651.GB30506@linux.vnet.ibm.com> References: <20170207210651.GB30506@linux.vnet.ibm.com> From: Andy Lutomirski Date: Wed, 8 Feb 2017 08:25:16 -0800 Message-ID: Subject: Re: PCID review? Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: "Paul E. McKenney" Cc: Andy Lutomirski , Borislav Petkov , Kees Cook , Dave Hansen , "linux-mm@kvack.org" On Tue, Feb 7, 2017 at 1:06 PM, Paul E. McKenney wrote: > On Tue, Feb 07, 2017 at 10:56:59AM -0800, Andy Lutomirski wrote: >> Quite a few people have expressed interest in enabling PCID on (x86) >> Linux. Here's the code: >> >> https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/log/?h=x86/pcid >> >> The main hold-up is that the code needs to be reviewed very carefully. >> It's quite subtle. In particular, "x86/mm: Try to preserve old TLB >> entries using PCID" ought to be looked at carefully to make sure the >> locking is right, but there are plenty of other ways this this could >> all break. >> >> Anyone want to take a look or maybe scare up some other reviewers? >> (Kees, you seemed *really* excited about getting this in.) > > Cool! > > So I can drop 61ec4c556b0d "rcu: Maintain special bits at bottom of > ->dynticks counter", correct? Nope. That's a different optimization. If you consider that patch ready, want to email me, the dynticks folks, and linux-mm as a reminder? --Andy -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org