[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <x49obl3s0tb.fsf@segfault.boston.devel.redhat.com>
Date: Tue, 18 Sep 2012 13:22:40 -0400
From: Jeff Moyer <jmoyer@...hat.com>
To: Mikulas Patocka <mpatocka@...hat.com>
Cc: Eric Dumazet <eric.dumazet@...il.com>,
Jens Axboe <axboe@...nel.dk>,
Andrea Arcangeli <aarcange@...hat.com>,
Jan Kara <jack@...e.cz>, dm-devel@...hat.com,
linux-kernel@...r.kernel.org,
Alexander Viro <viro@...iv.linux.org.uk>,
kosaki.motohiro@...fujitsu.com, linux-fsdevel@...r.kernel.org,
lwoodman@...hat.com, "Alasdair G. Kergon" <agk@...hat.com>
Subject: Re: [PATCH 0/4] Fix a crash when block device is read and block size is changed at the same time
Mikulas Patocka <mpatocka@...hat.com> writes:
> Hi Jeff
>
> Thanks for testing.
>
> It would be interesting ... what happens if you take the patch 3, leave
> "struct percpu_rw_semaphore bd_block_size_semaphore" in "struct
> block_device", but remove any use of the semaphore from fs/block_dev.c? -
> will the performance be like unpatched kernel or like patch 3? It could be
> that the change in the alignment affects performance on your CPU too, just
> differently than on my CPU.
I'll give it a try and report back.
> What is the CPU model that you used for testing?
http://ark.intel.com/products/53570/Intel-Xeon-Processor-E7-2860-%2824M-Cache-2_26-GHz-6_40-GTs-Intel-QPI%29
Cheers,
Jeff
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists