mm: consolidate warn_alloc_failed users

warn_alloc_failed is currently used from the page and vmalloc
allocators.  This is a good reuse of the code except that vmalloc would
appreciate a slightly different warning message.  This is already
handled by the fmt parameter except that

  "%s: page allocation failure: order:%u, mode:%#x(%pGg)"

is printed anyway.  This might be quite misleading because it might be a
vmalloc failure which leads to the warning while the page allocator is
not the culprit here.  Fix this by always using the fmt string and only
print the context that makes sense for the particular context (e.g.
order makes only very little sense for the vmalloc context).

Rename the function to not miss any user and also because a later patch
will reuse it also for !failure cases.

Link: http://lkml.kernel.org/r/20160929084407.7004-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 12 insertions, 15 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index bcfa647c1752..5ab2e30a1006 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2979,9 +2979,11 @@ static DEFINE_RATELIMIT_STATE(nopage_rs,
                 DEFAULT_RATELIMIT_INTERVAL,
                 DEFAULT_RATELIMIT_BURST);
 
-void warn_alloc_failed(gfp_t gfp_mask, unsigned int order, const char *fmt, ...)
+void warn_alloc(gfp_t gfp_mask, const char *fmt, ...)
 {
         unsigned int filter = SHOW_MEM_FILTER_NODES;
+        struct va_format vaf;
+        va_list args;
 
         if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) ||
             debug_guardpage_minorder() > 0)
@@ -2999,22 +3001,16 @@ void warn_alloc_failed(gfp_t gfp_mask, unsigned int order, const char *fmt, ...)
         if (in_interrupt() || !(gfp_mask & __GFP_DIRECT_RECLAIM))
                 filter &= ~SHOW_MEM_FILTER_NODES;
 
-        if (fmt) {
-                struct va_format vaf;
-                va_list args;
+        pr_warn("%s: ", current->comm);
 
-                va_start(args, fmt);
+        va_start(args, fmt);
+        vaf.fmt = fmt;
+        vaf.va = &args;
+        pr_cont("%pV", &vaf);
+        va_end(args);
 
-                vaf.fmt = fmt;
-                vaf.va = &args;
+        pr_cont(", mode:%#x(%pGg)\n", gfp_mask, &gfp_mask);
 
-                pr_warn("%pV", &vaf);
-
-                va_end(args);
-        }
-
-        pr_warn("%s: page allocation failure: order:%u, mode:%#x(%pGg)\n",
-                current->comm, order, gfp_mask, &gfp_mask);
         dump_stack();
         if (!should_suppress_show_mem())
                 show_mem(filter);
@@ -3680,7 +3676,8 @@ retry:
         }
 
 nopage:
-        warn_alloc_failed(gfp_mask, order, NULL);
+        warn_alloc(gfp_mask,
+                        "page allocation failure: order:%u", order);
 got_pg:
         return page;
 }