Re: [PATCH v7 0/5] vfs: Non-blockling buffered fs read (page cache only)

Christoph Hellwig
2015-03-27T08:48:41Z

On Fri, Mar 27, 2015 at 01:35:16AM -0700, Andrew Morton wrote:
> fincore() doesn't have to be ugly. Please address the design issues I
> raised. How is pread2() useful to the class of applications which
> cannot proceed until all data is available?

It actually makes them work correctly? preadv2( ..., DONTWAIT) will
return -EGAIN, which causes them to bounce to the threadpool where
they call preadv(...).