Messages in this thread | | | Date | Fri, 4 Feb 2011 10:04:57 -0500 | From | Vivek Goyal <> | Subject | Re: [PATCH v3 1/2] block: skip elevator data initialization for flush requests |
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On Thu, Feb 03, 2011 at 02:38:20PM +0100, Tejun Heo wrote: > Hey, Jens. > > On Thu, Feb 03, 2011 at 02:24:42PM +0100, Jens Axboe wrote: > > On 2011-02-02 23:55, Mike Snitzer wrote: > > > REQ_SORTED is not set for flush requests because they are never put on > > > the IO scheduler. > > > > That looks very wrong. REQ_SORTED gets set _when_ the request is sorted > > into the IO scheduler. This is gross misuse, a bad hack. > > The rationale behind suggesting was that it indicates to the allocator > that the request may be sorted as how the request will be used is > communicated using @rw_flags to the allocator. The patch is buggy > that the flag actually ends up on the request. Any better idea how to > communicate it?
Though you did not like the V1 of patch, personally I also liked just parsing FLUSH or FUA flag in get_request().
Or how about intoducing a helper function blk_rq_should_init_elevator() or something like that and this function will parse FLUSH, FUA flags.
Thanks Vivek
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