From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: [GIT PULL de-alpha] Make core code not need to know about Alpha for v4.15 Date: Wed, 25 Oct 2017 06:18:02 -0700 Message-ID: <20171025131802.GL3659@linux.vnet.ibm.com> References: <20171023210408.GA2930@linux.vnet.ibm.com> <20171025084548.mc7pqlshuzmtci4p@gmail.com> <20171025085414.GH3659@linux.vnet.ibm.com> <20171025090443.g6aahmn3ggu6vcon@gmail.com> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:46722 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750876AbdJYNSJ (ORCPT ); Wed, 25 Oct 2017 09:18:09 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9PDHFbo171740 for ; Wed, 25 Oct 2017 09:18:09 -0400 Received: from e12.ny.us.ibm.com (e12.ny.us.ibm.com [129.33.205.202]) by mx0b-001b2d01.pphosted.com with ESMTP id 2dtqybb6wq-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 25 Oct 2017 09:18:08 -0400 Received: from localhost by e12.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 25 Oct 2017 09:18:08 -0400 Content-Disposition: inline In-Reply-To: <20171025090443.g6aahmn3ggu6vcon@gmail.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, will.deacon@arm.com, mark.rutland@arm.com, snitzer@redhat.com, thor.thayer@linux.intel.com, viro@zeniv.linux.org.uk, davem@davemloft.net, shuah@kernel.org, mpe@ellerman.id.au, tj@kernel.org On Wed, Oct 25, 2017 at 11:04:43AM +0200, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > On Wed, Oct 25, 2017 at 10:45:48AM +0200, Ingo Molnar wrote: > > > > > > * Paul E. McKenney wrote: > > > > > > > Hello, Ingo, > > > > > > > > This series is a first step towards making the core kernel no longer > > > > need to consider DEC Alpha as a special case. This is accomplished > > > > by two sets of patches, followed by a Coccinelle script: > > > > > > > > 1. Patches 1/19 through 15/19 in the following patches, which > > > > change non-Coccinelle-susceptible instances of ACCESS_ONCE() > > > > to either READ_ONCE() or WRITE_ONCE(), as appropriate. Most of > > > > these patches are courtesy of Mark Rutland. > > > > > > > > 2. Patches 16/19 through 18/19 in the following patches, which > > > > add smp_read_barrier_depends() to READ_ONCE() and to Alpha's > > > > value-returning _release and _relaxed atomic read-modify-write > > > > operations, while also removing lockless_dereference() in favor > > > > of the modified READ_ONCE(). > > > > > > > > 3. A patch generated by Coccinelle (script in commit log) that > > > > converts ACCESS_ONCE() to either READ_ONCE() or WRITE_ONCE(), > > > > as appropriate. Of course, this patch should not be applied > > > > as-is to mainline, instead, the Coccinelle script should be > > > > re-run in order to account for any changes between now and > > > > the time of merging into mainline. > > > > > > > > A later series (most likely targeted to v4.16) will remove instances of > > > > smp_read_barrier_depends() that are made redundant by this series, that > > > > is to say, almost all of them. > > > > > > > > These changes are available in the git repository at: > > > > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git rcu/alpha-cocci > > > > > > > > for you to fetch changes up to d19fa5187a69bd7685e9c7452ce9e339b1b079fc: > > > > > > > > COCCINELLE: treewide: kill off ACCESS_ONCE() (2017-10-21 12:52:09 -0700) > > > > > > > > ---------------------------------------------------------------- > > > > Mark Rutland (14): > > > > dm integrity: Kill off ACCESS_ONCE() > > > > EDAC, altera: Kill off ACCESS_ONCE() > > > > firmware/ivc: Kill off ACCESS_ONCE() > > > > fs: dcache: Kill off ACCESS_ONCE() > > > > fs: ncpfs: Kill off ACCESS_ONCE() > > > > media: dvb_ringbuffer: Kill off ACCESS_ONCE() > > > > net: netlink/netfilter: Kill off ACCESS_ONCE() > > > > net/ipv4/tcp_input.c: Kill off ACCESS_ONCE() > > > > net: average: Kill off ACCESS_ONCE() > > > > samples: mic/mpssd/mpssd.c: Kill off ACCESS_ONCE() > > > > selftests/powerpc: Kill off ACCESS_ONCE() > > > > workqueue: Kill off ACCESS_ONCE() > > > > rcutorture: formal: Prepare for ACCESS_ONCE() removal > > > > COCCINELLE: treewide: kill off ACCESS_ONCE() > > > > > > None of the patches from Mark include your Signed-off-by - I'll add them, let me > > > know if that's not OK. I suppose this happened because you rebased his tree? > > > > I did pull his tree rather than applying from email, [...] > > You might have pulled it, but the commits in rcu/alpha-cocci suggest that the tree > was also rebased: > > commit d19fa5187a69bd7685e9c7452ce9e339b1b079fc > Author: Mark Rutland > AuthorDate: Thu Oct 19 10:42:03 2017 -0700 > Commit: Paul E. McKenney > CommitDate: Sat Oct 21 12:52:09 2017 -0700 > > COCCINELLE: treewide: kill off ACCESS_ONCE() > > Note the "Commit:" field which says the commit was created by you, not by Mark. Hmmm... Looking back through my old versions, it looks like my original pull from Mark's git tree did the rebase. Not sure how that happened, given that both are based on v4.14-rc4. I am going to have to proceed more carefully next time! Thanx, Paul