]> pilppa.com Git - linux-2.6-omap-h63xx.git/commit
Do not disable interrupts when reading min_free_kbytes
authorMel Gorman <mel@csn.ul.ie>
Sun, 6 May 2007 21:49:30 +0000 (14:49 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Mon, 7 May 2007 19:12:53 +0000 (12:12 -0700)
commit3b1d92c56514987010bb0201b5c71aeb633fc4f8
treef31a72692c35eb27fc94590964ba389776c0439f
parent8da3430d8a7f885c2bf65121181d76c9d290a86e
Do not disable interrupts when reading min_free_kbytes

The sysctl handler for min_free_kbytes calls setup_per_zone_pages_min() on
read or write.  This function iterates through every zone and calls
spin_lock_irqsave() on the zone LRU lock.  When reading min_free_kbytes,
this is a total waste of time that disables interrupts on the local
processor.  It might even be noticable machines with large numbers of zones
if a process started constantly reading min_free_kbytes.

This patch only calls setup_per_zone_pages_min() only on write. Tested on
an x86 laptop and it did the right thing.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/page_alloc.c