On Mon, Jul 31, 2017 at 07:16:59AM +0900, Minchan Kim wrote:
rw_page's gain is reducing of dynamic allocation in swap path
as well as performance gain thorugh avoiding bio allocation.
And it would be important in memory pressure situation.
There is no need for any dynamic allocation when using the bio
path. Take a look at __blkdev_direct_IO_simple for an example
that doesn't do any allocations.