From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Sandeen <sandeen@redhat.com>
Subject: Re: Unusual code in mballoc.c.
Date: Sat, 27 Sep 2008 23:01:11 -0500
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References: <200809281156.12688.rusty@rustcorp.com.au>
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Cc: linux-ext4@vger.kernel.org, Alex Tomas <alex@clusterfs.com>,
	Mike Travis <travis@sgi.com>
To: Rusty Russell <rusty@rustcorp.com.au>
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Rusty Russell wrote:
> Hi all,
> 
>    A grep lead me to fs/ext4/mballoc.c:
> 
> Line 2551:
> 	for (i = 0; i < nr_cpu_ids; i++) {
> 
> This is more normally "for_each_possible_cpu(i)".
> 
> Line 4097:
> 	ac->ac_lg = &sbi->s_locality_groups[get_cpu()];
> 	put_cpu();
> 
> This is presumably someone suppressing a warning.   It should be:
> 	ac->ac_lg = &sbi->s_locality_groups[raw_smp_processor_id()];
> 
> Thanks,
> Rusty.

Hi Rusty - I sent a patch for this a while back...

http://repo.or.cz/w/ext4-patch-queue.git?a=blob;f=ext4-use-percpu-data-for-lg_prealloc_list;h=8ddebb7f6054f70e34b142d7ae6f314d6629aac7;hb=HEAD

Thanks,
-Eric