From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753252Ab2AGSn5 (ORCPT ); Sat, 7 Jan 2012 13:43:57 -0500 Received: from e06smtp17.uk.ibm.com ([195.75.94.113]:48780 "EHLO e06smtp17.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752497Ab2AGSn4 convert rfc822-to-8bit (ORCPT ); Sat, 7 Jan 2012 13:43:56 -0500 Date: Sat, 7 Jan 2012 19:43:48 +0100 From: Martin Schwidefsky To: Linus Torvalds Cc: Ingo Molnar , Andreas Schwab , linux-kernel@vger.kernel.org, Peter Zijlstra , Mike Galbraith , Thomas Gleixner , Andrew Morton Subject: Re: [GIT PULL] scheduler changes for v3.3 Message-ID: <20120107194348.77b42573@de.ibm.com> In-Reply-To: References: <20120105140846.GA32342@elte.hu> Organization: IBM Corporation X-Mailer: Claws Mail 3.8.0 (GTK+ 2.24.8; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT x-cbid: 12010718-0542-0000-0000-00000097E41E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 6 Jan 2012 08:58:55 -0800 Linus Torvalds wrote: > On Thu, Jan 5, 2012 at 6:08 AM, Ingo Molnar wrote: > > > > Please pull the latest sched-core-for-linus git tree from: > > > >   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-core-for-linus > > Ugh. So I got conflicts on this one. Big deal, fix them up. > > But as I was fixing them up, I hit two problems that I wanted people > to take a look at: > > - some of the code was utter crap. Look at my fixup for > include/asm-generic/cputime.h, for example. Notice how I had to change > __msecs to __usec, and notice the bogus semicolons that I removed? Yes, the semicolons had been crap and the parameter name suboptimal. > This came in through commit 648616343cdb ("[S390] cputime: add > sparse checking and cleanup") which is also mis-named: it's not > S390-specific. Martin, please take a look. Yeah, I had that patch in the s390 tree before it got moved to a tip tree. I tend to tag everything in my tree with [S390]. > - I did not do the right thing for the "usecs_to_cputime64()" fixup. > Please take a look at commit 34845636a184 ("procfs: do not confuse > jiffies with cputime64_t") which introduced that "usecs_to_cputime64() > thing, and which clashes badly with the sparse cleanups. There had been some fallout from the two changes. > And by "clashes badly", I mean it. The sparse cleanups added a lot of > casts between the types, which means that the mindless > > +#define usecs_to_cputime64(us) usecs_to_cputime(us) > > introduced by that commit 34845636a184 is now likely *wrong*, because > "usecs_to_cputime()" now explicitly casts to a non-64-bit cputime_t. Surprisingly sparse does not give a warning if the base type of two __nowarn types is the same. All three VIRT_CPU_ACCOUNTING architectures use u64 or unsigned long long for cputime_t and cputime64_t. It does work but I agree that an explicit cast to cputime64_t would be better. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin.