mm: neaten warn_alloc_failed

Add __attribute__((format (printf...) to the function to validate format
and arguments.  Use vsprintf extension %pV to avoid any possible message
interleaving.  Coalesce format string.  Convert printks/pr_warning to
pr_warn.

[akpm@linux-foundation.org: use the __printf() macro]
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/mm.h

@@ -1334,7 +1334,8 @@ extern void si_meminfo(struct sysinfo * val);
 extern void si_meminfo_node(struct sysinfo *val, int nid);
 extern int after_bootmem;
 
-extern void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...);
+extern __printf(3, 4)
+void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...);
 
 extern void setup_per_cpu_pageset(void);
 

mm/page_alloc.c

@@ -1754,7 +1754,6 @@ static DEFINE_RATELIMIT_STATE(nopage_rs,
 
 void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...)
 {
-	va_list args;
 	unsigned int filter = SHOW_MEM_FILTER_NODES;
 
 	if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs))
@@ -1773,13 +1772,20 @@ void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...)
 		filter &= ~SHOW_MEM_FILTER_NODES;
 
 	if (fmt) {
-		printk(KERN_WARNING);
+		struct va_format vaf;
+		va_list args;
+
 		va_start(args, fmt);
-		vprintk(fmt, args);
+
+		vaf.fmt = fmt;
+		vaf.va = &args;
+
+		pr_warn("%pV", &vaf);
+
 		va_end(args);
 	}
 
-	pr_warning("%s: page allocation failure: order:%d, mode:0x%x\n",
+	pr_warn("%s: page allocation failure: order:%d, mode:0x%x\n",
 		current->comm, order, gfp_mask);
 
 	dump_stack();

mm/vmalloc.c

@@ -1593,8 +1593,8 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 	return area->addr;
 
 fail:
-	warn_alloc_failed(gfp_mask, order, "vmalloc: allocation failure, "
-			  "allocated %ld of %ld bytes\n",
+	warn_alloc_failed(gfp_mask, order,
+			  "vmalloc: allocation failure, allocated %ld of %ld bytes\n",
 			  (area->nr_pages*PAGE_SIZE), area->size);
 	vfree(area->addr);
 	return NULL;