From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <46A03E63.2080508@yahoo.com.au> Date: Fri, 20 Jul 2007 14:47:31 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [PATCH] hugetlbfs read() support References: <1184376214.15968.9.camel@dyn9047017100.beaverton.ibm.com> <20070718221950.35bbdb76.akpm@linux-foundation.org> <1184860309.18188.90.camel@dyn9047017100.beaverton.ibm.com> <20070719095850.6e09b0e8.akpm@linux-foundation.org> <20070719170759.GE2083@us.ibm.com> In-Reply-To: <20070719170759.GE2083@us.ibm.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nishanth Aravamudan Cc: Andrew Morton , Badari Pulavarty , Bill Irwin , lkml , linux-mm List-ID: Nishanth Aravamudan wrote: > On 19.07.2007 [09:58:50 -0700], Andrew Morton wrote: > >>On Thu, 19 Jul 2007 08:51:49 -0700 Badari Pulavarty wrote: >> >> >>>>>+ } >>>>>+ >>>>>+ offset += ret; >>>>>+ retval += ret; >>>>>+ len -= ret; >>>>>+ index += offset >> HPAGE_SHIFT; >>>>>+ offset &= ~HPAGE_MASK; >>>>>+ >>>>>+ page_cache_release(page); >>>>>+ if (ret == nr && len) >>>>>+ continue; >>>>>+ goto out; >>>>>+ } >>>>>+out: >>>>>+ return retval; >>>>>+} >>>> >>>>This code doesn't have all the ghastly tricks which we deploy to >>>>handle concurrent truncate. >>> >>>Do I need to ? Baaahh!! I don't want to deal with them. >> >>Nick, can you think of any serious consequences of a read/truncate >>race in there? I can't.. >> >> >>>All I want is a simple read() to get my oprofile working. Please >>>advise. >> >>Did you consider changing oprofile userspace to read the executable >>with mmap? > > > It's not actually oprofile's code, though, it's libbfd (used by > oprofile). And it works fine (presumably) for other binaries. So... what's the problem with changing it? The fact that it is a library doesn't really make a difference except that you'll also help everyone else who links with it. It won't break backwards compatibility, and it will work on older kernels... -- SUSE Labs, Novell Inc. -- 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