Re: [PATCH v2] writeback: avoid race when update bandwidth

Wanpeng Li
2012-06-12T11:58:32Z

On Tue, Jun 12, 2012 at 07:52:19PM +0800, Fengguang Wu wrote:
>On Tue, Jun 12, 2012 at 07:46:01PM +0800, Wanpeng Li wrote:
>> From: Wanpeng Li <liwp@linux.vnet.ibm.com>
>>
>> "V1 -> V2"
>> * remove dirty_lock
>>
>> Since bdi->wb.list_lock is used to protect the b_* lists,
>> so the flushers who call wb_writeback to writeback pages will
>> stuck when bandwidth update policy holds this lock. In order
>> to avoid this race we can introduce a new bandwidth_lock who
>> is responsible for protecting bandwidth update policy.
>>
>> Signed-off-by: Wanpeng Li <liwp.linux@gmail.com>
>
>Applied with a new title "writeback: use a standalone lock for
>updating write bandwidth". "race" is sensitive because it often
>refers to some locking error.

OK, Thanks a lot.

Regards,
Wanpeng Li