Commit 6f718656 authored by Wu Fengguang's avatar Wu Fengguang
Browse files

writeback: add bdi_dirty_limit() kernel-doc 



Clarify the bdi_dirty_limit() comment.

Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarWu Fengguang <fengguang.wu@intel.com>
parent e185dda8

mm/page-writeback.c

+9 −2
Original line number Diff line number Diff line
@@ -437,10 +437,17 @@ void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty) 
	*pdirty = dirty;

}



/*

/**

 * bdi_dirty_limit - @bdi's share of dirty throttling threshold

 * @bdi: the backing_dev_info to query

 * @dirty: global dirty limit in pages

 *

 * Returns @bdi's dirty limit in pages. The term "dirty" in the context of

 * dirty balancing includes all PG_dirty, PG_writeback and NFS unstable pages.

 * And the "limit" in the name is not seriously taken as hard limit in

 * balance_dirty_pages().

 *

 * Allocate high/low dirty limits to fast/slow devices, in order to prevent

 * It allocates high/low dirty limits to fast/slow devices, in order to prevent

 * - starving fast devices

 * - piling up dirty pages (that will take long time to sync) on slow devices

 *