mm/vmscan: throttle reclaim when no progress is being made

Memcg reclaim throttles on congestion if no reclaim progress is made.
This makes little sense, it might be due to writeback or a host of other
factors.

For !memcg reclaim, it's messy.  Direct reclaim primarily is throttled
in the page allocator if it is failing to make progress.  Kswapd
throttles if too many pages are under writeback and marked for immediate
reclaim.

This patch explicitly throttles if reclaim is failing to make progress.

[[email protected]: Remove redundant code]

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Andreas Dilger <[email protected]>
Cc: "Darrick J . Wong" <[email protected]>
Cc: Dave Chinner <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: NeilBrown <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: "Theodore Ts'o" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions