Messages in this thread | | | Date | Tue, 31 Jan 2012 18:57:54 +0800 | From | Wu Fengguang <> | Subject | Re: [PATCH] fix readahead pipeline break caused by block plug |
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On Tue, Jan 31, 2012 at 05:46:21AM -0500, Christoph Hellwig wrote: > On Tue, Jan 31, 2012 at 06:34:16PM +0800, Wu Fengguang wrote: > > } > > > > + blk_start_plug(&plug); > > written = mapping->a_ops->direct_IO(WRITE, iocb, iov, pos, *nr_segs); > > + blk_finish_plug(&plug); > > Please move the plugging into ->direct_IO for both read and write, as > that is the boundary between generic highlevel code, and low-level block > code that should know about plugs.
The problem is, there are a dozen of ->direct_IO callback functions. While there are only two ->direct_IO() callers, one for READ and another for WRITE, which are much easier to deal with.
Thanks, Fengguang
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