Revision bbdb396a60b2ebf7de3b717991e5d3e28c8b7bbd authored by Martin Bligh on 28 October 2006, 17:38:25 UTC, committed by Linus Torvalds on 28 October 2006, 18:30:51 UTC
If try_to_free_pages / balance_pgdat are called with a gfp_mask specifying
GFP_IO and/or GFP_FS, they will reclaim the requisite number of pages, and the
reset prev_priority to DEF_PRIORITY (or to some other high (ie: unurgent)
value).

However, another reclaimer without those gfp_mask flags set (say, GFP_NOIO)
may still be struggling to reclaim pages.  The concurrent overwrite of
zone->prev_priority will cause this GFP_NOIO thread to unexpectedly cease
deactivating mapped pages, thus causing reclaim difficulties.

Fix this is to key the distress calculation not off zone->prev_priority, but
also take into account the local caller's priority by using
min(zone->prev_priority, sc->priority)

Signed-off-by: Martin J. Bligh <mbligh@google.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 parent 3bb1a85
Raw File
Makefile
#
# Makefile for the kernel block layer
#

obj-$(CONFIG_BLOCK) := elevator.o ll_rw_blk.o ioctl.o genhd.o scsi_ioctl.o

obj-$(CONFIG_IOSCHED_NOOP)	+= noop-iosched.o
obj-$(CONFIG_IOSCHED_AS)	+= as-iosched.o
obj-$(CONFIG_IOSCHED_DEADLINE)	+= deadline-iosched.o
obj-$(CONFIG_IOSCHED_CFQ)	+= cfq-iosched.o

obj-$(CONFIG_BLK_DEV_IO_TRACE)	+= blktrace.o
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