Commit bdb75b36 authored Aug 19, 2015 by Vinayak Menon

lowmemorykiller: avoid false adaptive LMK triggers



In vmpressure notifier of LMK, shift_adj would have been set
by a previous invocation of notifier, which is not followed by
a lowmem_shrink yet. If this is follwed by a lower vmpressure,
and then by a lowmem_shrink, ALMK still triggers because of the
previous higher vmpressure notification. This is wrong.
Since vmpressure has improved, reset shift_adj to avoid false
adaptive LMK trigger.

CRs-fixed: 893699
Change-Id: I2d77103d7c8f4d8a66e4652cba78e619a7bcef9a
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>

parent 247cd183

drivers/staging/android/lowmemorykiller.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -171,6 +171,15 @@ static int lmk_vmpressure_notifier(struct notifier_block *nb,
		trace_almk_vmpressure(pressure, other_free,
		other_file);
		}
		} else if (atomic_read(&shift_adj)) {
		/*
		* shift_adj would have been set by a previous invocation
		* of notifier, which is not followed by a lowmem_shrink yet.
		* Since vmpressure has improved, reset shift_adj to avoid
		* false adaptive LMK trigger.
		*/
		trace_almk_vmpressure(pressure, other_free, other_file);
		atomic_set(&shift_adj, 0);
		}

		return 0;