mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled
The patch "mm, page_alloc: warn_alloc print nodemask" implicitly sets
the allocation nodemask to cpuset_current_mems_allowed when there is no
effective mempolicy. cpuset_current_mems_allowed is only effective when
cpusets are enabled, which is also printed by warn_alloc(), so setting
the nodemask to cpuset_current_mems_allowed is redundant and prevents
debugging issues where ac->nodemask is not set properly in the page
allocator.
This provides better debugging output since
cpuset_print_current_mems_allowed() is already provided.
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: David Rientjes <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a179607..c21b336 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3034,7 +3034,6 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
va_list args;
static DEFINE_RATELIMIT_STATE(nopage_rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
- nodemask_t *nm = (nodemask) ? nodemask : &cpuset_current_mems_allowed;
if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) ||
debug_guardpage_minorder() > 0)
@@ -3048,11 +3047,16 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
pr_cont("%pV", &vaf);
va_end(args);
- pr_cont(", mode:%#x(%pGg), nodemask=%*pbl\n", gfp_mask, &gfp_mask, nodemask_pr_args(nm));
+ pr_cont(", mode:%#x(%pGg), nodemask=", gfp_mask, &gfp_mask);
+ if (nodemask)
+ pr_cont("%*pbl\n", nodemask_pr_args(nodemask));
+ else
+ pr_cont("(null)\n");
+
cpuset_print_current_mems_allowed();
dump_stack();
- warn_alloc_show_mem(gfp_mask, nm);
+ warn_alloc_show_mem(gfp_mask, nodemask);
}
static inline struct page *
