From: Andrew Morton <akpm@osdl.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Readahead
Date: Mon, 26 Sep 2005 21:24:46 -0700 [thread overview]
Message-ID: <20050926212446.365778e3.akpm@osdl.org> (raw)
In-Reply-To: <Pine.LNX.4.44L0.0509262234500.32418-100000@netrider.rowland.org>
Alan Stern <stern@rowland.harvard.edu> wrote:
>
> Can somebody please tell me where the code is that performs optimistic
> readahead when a process does sequential reads on a block device?
mm/readahead.c:__do_page_cache_readahead() is the main one. Use
dump_stack() to be sure.
> And can someone explain why those readahead calls are allowed to extend
> beyond the end of the device?
It has a check in there for reads past the blockdev mapping's i_size.
Maybe i_size is wrong, or maybe the code is wrong, or maybe it's a
different caller.
next prev parent reply other threads:[~2005-09-27 4:25 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-09-27 2:38 Readahead Alan Stern
2005-09-27 3:06 ` Readahead Randy.Dunlap
2005-09-27 4:24 ` Andrew Morton [this message]
2005-09-28 18:40 ` Readahead Alan Stern
-- strict thread matches above, loose matches on Subject: below --
2003-11-01 17:22 READAHEAD Voluspa
2003-10-30 19:23 READAHEAD age
2003-10-30 21:44 ` READAHEAD Andrew Morton
2003-10-31 7:43 ` READAHEAD Nuno Silva
2003-10-31 8:03 ` READAHEAD Andrew Morton
2003-10-31 12:20 ` READAHEAD age
2003-10-31 9:28 ` READAHEAD Andrew Morton
2003-10-31 9:29 ` READAHEAD Andrew Morton
2003-11-01 9:15 ` READAHEAD age
2003-11-03 0:15 ` READAHEAD Derek Foreman
2002-04-16 20:21 readahead Andries.Brouwer
2002-04-16 19:10 readahead Andries.Brouwer
2002-04-16 19:23 ` readahead Andrew Morton
2002-04-16 19:33 ` readahead Jens Axboe
2002-04-16 13:54 readahead Andries.Brouwer
2002-04-16 16:08 ` readahead Steven Cole
2002-04-16 18:25 ` readahead Andrew Morton
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