mm, show_mem: suppress page counts in non-blockable contexts
On large systems with a lot of memory, walking all RAM to determine page
types may take a half second or even more.
In non-blockable contexts, the page allocator will emit a page allocation
failure warning unless __GFP_NOWARN is specified. In such contexts, irqs
are typically disabled and such a lengthy delay may even result in NMI
watchdog timeouts.
To fix this, suppress the page walk in such contexts when printing the
page allocation failure warning.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index c2e955e..a57436e 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -623,6 +623,8 @@
printk(KERN_INFO "Mem-info:\n");
show_free_areas(filter);
+ if (filter & SHOW_MEM_FILTER_PAGE_COUNT)
+ return;
printk(KERN_INFO "Node memory in pages:\n");
for_each_online_pgdat(pgdat) {
unsigned long present;