Re: [PATCH 07/10] fs: make generic file read/write functions plug

[Jens Axboe]

On 2011-03-09 11:38, hch@xxxxxxxxxxxxx wrote:
> On Tue, Mar 08, 2011 at 01:38:08PM +0100, Jens Axboe wrote:
>> -#define DP_UNPLUG             8 /* equals REQ_UNPLUG  */
>> +#define DP_UNPLUG             8 /* not used anymore   */
> 
> The way this is used might need some more review.  It seems like DRBD is
> trying to propagate unplug requests over the wire, which is
> functionality we lose now.

But that use case is pretty questionable. The receiving end should just
do its own plugging, if it's beneficial.

>> + * The various wait functions, such as wait_on_writeback_range() will
>> + * ultimately call sync_page() which will ultimately call
>> + * blk_run_backing_dev(), which will end up unplugging the device queue.
> 
> This comment describes code that doesn't exist anymore on your branch.

Thanks, I'll kill those.


-- 
Jens Axboe

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