lkml.org 
[lkml]   [2010]   [Jul]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 3/7] block: push down BKL into .open and .release
On 2010-07-07 16:51, Arnd Bergmann wrote:
> The open and release block_device_operations are currently
> called with the BKL held. In order to change that, we must
> first make sure that all drivers that currently rely
> on this have no regressions.
>
> This blindly pushes the BKL into all .open and .release
> operations for all block drivers to prepare for the
> next step. The drivers can subsequently replace the BKL
> with their own locks or remove it completely when it can
> be shown that it is not needed.
>
> The functions blkdev_get and blkdev_put are the only
> remaining users of the big kernel lock in the block
> layer, besides a few uses in the ioctl code, none
> of which need to serialize with blkdev_{get,put}.
>
> Most of these two functions is also under the protection
> of bdev->bd_mutex, including the actual calls to
> ->open and ->release, and the common code does not
> access any global data structures that need the BKL.

This is missing an smp_lock.h include in i2o as well.
You seem to only add these sporadically, I think that
is a bit unsafe since you are relying on unknown
include hierarchies. That tends to break on one arch
or config even if it works in another.

--
Jens Axboe



\
 
 \ /
  Last update: 2010-07-08 10:43    [W:0.084 / U:0.320 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site