Commit 132b0d21 authored by Mel Gorman's avatar Mel Gorman Committed by Linus Torvalds
Browse files

mm/page_alloc: remove the throttling logic from the page allocator 

The page allocator stalls based on the number of pages that are waiting
for writeback to start but this should now be redundant.
shrink_inactive_list() will wake flusher threads if the LRU tail are
unqueued dirty pages so the flusher should be active.  If it fails to
make progress due to pages under writeback not being completed quickly
then it should stall on VMSCAN_THROTTLE_WRITEBACK.

Link: https://lkml.kernel.org/r/20211022144651.19914-6-mgorman@techsingularity.net


Signed-off-by: default avatarMel Gorman <mgorman@techsingularity.net>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Darrick J . Wong" <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Rik van Riel <riel@surriel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8d58802f

mm/page_alloc.c

+1 −20
Original line number Diff line number Diff line
@@ -4791,30 +4791,11 @@ should_reclaim_retry(gfp_t gfp_mask, unsigned order, 
		trace_reclaim_retry_zone(z, order, reclaimable,

				available, min_wmark, *no_progress_loops, wmark);

		if (wmark) {

			/*

			 * If we didn't make any progress and have a lot of

			 * dirty + writeback pages then we should wait for

			 * an IO to complete to slow down the reclaim and

			 * prevent from pre mature OOM

			 */

			if (!did_some_progress) {

				unsigned long write_pending;



				write_pending = zone_page_state_snapshot(zone,

							NR_ZONE_WRITE_PENDING);



				if (2 * write_pending > reclaimable) {

					congestion_wait(BLK_RW_ASYNC, HZ/10);

					return true;

				}

			}



			ret = true;

			goto out;

			break;

		}

	}



out:

	/*

	 * Memory allocation/reclaim might be called from a WQ context and the

	 * current implementation of the WQ concurrency control doesn't