tools: fix -Wunused-result in linux.c

Fix the following -Wunused-result warnings on posix_memalign()
return values and add error handling.

./shared/linux.c:100:25: warning: ignoring return value of `posix_memalign' declared with attribute `warn_unused_result' [-Wunused-result]
  100 |          posix_memalign(&p, cachep->align, cachep->size);
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../shared/linux.c: In function `kmem_cache_alloc_bulk':
../shared/linux.c:198:33: warning: ignoring return value of `posix_memalign' declared with attribute `warn_unused_result' [-Wunused-result]
  198 |          posix_memalign(&p[i], cachep->align,
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  199 |                                cachep->size);
      |                                ~~~~~~~~~~~~~

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Shuah Khan <[email protected]>
Reviewed-by: Lorenzo Stoakes <[email protected]>
Reviewed-by: Liam R. Howlett <[email protected]>
Cc: Sidhartha Kumar <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: shuahkh

tools/testing/shared/linux.c

@@ -96,10 +96,13 @@ void *kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,
 		p = node;
 	} else {
 		pthread_mutex_unlock(&cachep->lock);
-		if (cachep->align)
-			posix_memalign(&p, cachep->align, cachep->size);
-		else
+		if (cachep->align) {
+			if (posix_memalign(&p, cachep->align, cachep->size) < 0)
+				return NULL;
+		} else {
 			p = malloc(cachep->size);
+		}
+
 		if (cachep->ctor)
 			cachep->ctor(p);
 		else if (gfp & __GFP_ZERO)
@@ -195,8 +198,9 @@ int kmem_cache_alloc_bulk(struct kmem_cache *cachep, gfp_t gfp, size_t size,
 			}
 
 			if (cachep->align) {
-				posix_memalign(&p[i], cachep->align,
-					       cachep->size);
+				if (posix_memalign(&p[i], cachep->align,
+					       cachep->size) < 0)
+					break;
 			} else {
 				p[i] = malloc(cachep->size);
 				if (!p[i])