From: Linus Torvalds <torvalds@linux-foundation.org>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mikulas Patocka <mpatocka@redhat.com>,
Jens Axboe <axboe@kernel.dk>,
Jeff Chua <jeff.chua.linux@gmail.com>,
Lai Jiangshan <laijs@cn.fujitsu.com>, Jan Kara <jack@suse.cz>,
lkml <linux-kernel@vger.kernel.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH] Introduce a method to catch mmap_region (was: Recent kernel "mount" slow)
Date: Wed, 28 Nov 2012 11:53:31 -0800 [thread overview]
Message-ID: <CA+55aFzfvQNtaS-B+A-vLk6jwOPy67n823Hua3kiR0sCTCw0yQ@mail.gmail.com> (raw)
In-Reply-To: <20121128194314.GF4939@ZenIV.linux.org.uk>
On Wed, Nov 28, 2012 at 11:43 AM, Al Viro <viro@zeniv.linux.org.uk> wrote:
> Have a
> private vm_operations - a copy of generic_file_vm_ops with ->open()/->close()
> added to it.
That sounds more reasonable.
However, I suspect the *most* reasonable thing to do is to just remove
the whole damn thing. We really shouldn't care about mmap. If somebody
does a mmap on a block device, and somebody else then changes the
block size, why-ever should we bother to go through any contortions at
*all* to make that kind of insane behavior do anything sane at all.
Just let people mmap things. Then just let the normal page cache
invalidation work right. In fact, it is entirely possible that we
could/should just not even invalidate the page cache at all, just make
sure that the buffer heads attached to any pages get disconnected. No?
Linus
next prev parent reply other threads:[~2012-11-28 19:53 UTC|newest]
Thread overview: 81+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAAJw_ZtbhE5Jtd4PsWx8a23QdFTW7aMrKBmRf-bo5Wrean9Xhg@mail.gmail.com>
2012-11-20 18:09 ` Recent kernel "mount" slow Jan Kara
2012-11-21 15:46 ` Jeff Chua
2012-11-22 14:30 ` Jeff Chua
2012-11-22 19:21 ` Linus Torvalds
2012-11-23 13:24 ` Jens Axboe
2012-11-23 22:21 ` Jeff Chua
2012-11-23 23:31 ` Jeff Chua
2012-11-23 23:48 ` Jeff Chua
2012-11-24 21:09 ` Mikulas Patocka
2012-11-24 23:23 ` Jeff Chua
2012-11-27 5:57 ` Jeff Chua
2012-11-27 7:38 ` Jens Axboe
2012-11-27 7:44 ` Jens Axboe
2012-11-27 8:45 ` Jeff Chua
2012-11-27 10:06 ` Jeff Chua
2012-11-27 12:33 ` Jens Axboe
2012-11-28 3:57 ` Mikulas Patocka
2012-11-28 8:33 ` Jens Axboe
2012-11-28 13:05 ` Jeff Chua
2012-11-28 17:25 ` [PATCH] Introduce a method to catch mmap_region (was: Recent kernel "mount" slow) Mikulas Patocka
2012-11-28 19:15 ` Linus Torvalds
2012-11-28 19:43 ` Al Viro
2012-11-28 19:53 ` Linus Torvalds [this message]
2012-11-28 22:01 ` [PATCH v2] Do a proper locking for mmap and block size change Mikulas Patocka
2012-11-29 17:19 ` Linus Torvalds
2012-11-29 18:23 ` Mikulas Patocka
2012-11-29 18:46 ` Linus Torvalds
2012-11-29 19:02 ` Linus Torvalds
2012-11-29 19:15 ` Chris Mason
2012-11-29 19:26 ` Linus Torvalds
2012-11-29 19:48 ` Chris Mason
2012-11-29 19:55 ` Linus Torvalds
2012-11-29 20:10 ` Linus Torvalds
2012-11-29 20:52 ` Linus Torvalds
2012-11-29 21:29 ` Chris Mason
2012-11-29 22:16 ` Linus Torvalds
2012-11-29 22:36 ` Linus Torvalds
2012-11-30 1:16 ` Chris Mason
2012-11-30 2:13 ` Linus Torvalds
2012-11-30 2:27 ` Chris Mason
2012-11-30 2:49 ` Dave Chinner
2012-11-30 14:31 ` Chris Mason
2012-11-30 16:42 ` Linus Torvalds
2012-11-30 16:36 ` Christoph Hellwig
2012-11-30 22:40 ` Dave Chinner
2012-11-30 23:09 ` Christoph Hellwig
2012-11-29 19:50 ` Linus Torvalds
2012-11-28 19:50 ` [PATCH] Introduce a method to catch mmap_region (was: Recent kernel "mount" slow) Mikulas Patocka
2012-11-28 20:03 ` Linus Torvalds
2012-11-28 20:13 ` Linus Torvalds
2012-11-28 20:32 ` Linus Torvalds
2012-11-28 20:47 ` Linus Torvalds
2012-11-28 22:10 ` Mikulas Patocka
2012-11-28 21:29 ` Mikulas Patocka
2012-11-28 22:52 ` Linus Torvalds
2012-11-28 23:13 ` Linus Torvalds
2012-11-29 1:20 ` Mikulas Patocka
2012-11-29 0:38 ` Mikulas Patocka
2012-11-29 2:04 ` Linus Torvalds
2012-11-29 2:58 ` Linus Torvalds
2012-11-29 6:16 ` Linus Torvalds
2012-11-29 6:25 ` Al Viro
2012-11-29 6:30 ` Al Viro
2012-11-29 6:37 ` Linus Torvalds
2012-11-29 6:45 ` Al Viro
2012-11-29 10:57 ` Jeff Chua
2012-11-29 6:33 ` Linus Torvalds
2012-11-29 14:12 ` Chris Mason
2012-11-29 17:26 ` Chris Mason
2012-11-29 17:26 ` Linus Torvalds
2012-11-29 17:51 ` Chris Mason
2012-11-29 18:12 ` Linus Torvalds
2012-11-28 3:59 ` [PATCH 1/2] percpu-rwsem: use synchronize_sched_expedited Mikulas Patocka
2012-11-28 4:01 ` [PATCH 2/2] block_dev: don't take the write lock if block size doesn't change Mikulas Patocka
2012-11-28 14:24 ` Jeff Chua
2012-11-28 22:03 ` Mikulas Patocka
2012-11-28 14:19 ` [PATCH 1/2] percpu-rwsem: use synchronize_sched_expedited Jeff Chua
2012-11-30 0:06 ` Andrew Morton
2012-11-30 3:00 ` Mikulas Patocka
2012-11-30 13:42 ` Paul E. McKenney
2012-11-30 18:57 ` Oleg Nesterov
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