[PATCH 01/31] mm: serialize access to min_free_kbytes
From: Suresh Jayaraman <hidden>
Date: 2009-10-01 14:03:23
Also in:
linux-mm, lkml
From: Peter Zijlstra <redacted> There is a small race between the procfs caller and the memory hotplug caller of setup_per_zone_wmarks(). Not a big deal, but the next patch will add yet another caller. Time to close the gap. Signed-off-by: Peter Zijlstra <redacted> Signed-off-by: Suresh Jayaraman <redacted> --- mm/page_alloc.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) Index: mmotm/mm/page_alloc.c ===================================================================
--- mmotm.orig/mm/page_alloc.c
+++ mmotm/mm/page_alloc.c@@ -121,6 +121,7 @@ static char * const zone_names[MAX_NR_ZO "Movable", }; +static DEFINE_SPINLOCK(min_free_lock); int min_free_kbytes = 1024; unsigned long __meminitdata nr_kernel_pages;
@@ -4448,13 +4449,13 @@ static void setup_per_zone_lowmem_reserv } /** - * setup_per_zone_wmarks - called when min_free_kbytes changes + * __setup_per_zone_wmarks - called when min_free_kbytes changes * or when memory is hot-{added|removed} * * Ensures that the watermark[min,low,high] values for each zone are set * correctly with respect to min_free_kbytes. */ -void setup_per_zone_wmarks(void) +static void __setup_per_zone_wmarks(void) { unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); unsigned long lowmem_pages = 0;
@@ -4552,6 +4553,15 @@ static void __init setup_per_zone_inacti calculate_zone_inactive_ratio(zone); } +void setup_per_zone_wmarks(void) +{ + unsigned long flags; + + spin_lock_irqsave(&min_free_lock, flags); + __setup_per_zone_wmarks(); + spin_unlock_irqrestore(&min_free_lock, flags); +} + /* * Initialise min_free_kbytes. *
@@ -4587,7 +4597,7 @@ static int __init init_per_zone_wmark_mi min_free_kbytes = 128; if (min_free_kbytes > 65536) min_free_kbytes = 65536; - setup_per_zone_wmarks(); + __setup_per_zone_wmarks(); setup_per_zone_lowmem_reserve(); setup_per_zone_inactive_ratio(); return 0;