slub: make ->remote_node_defrag_ratio unsigned int

->remote_node_defrag_ratio is in range 0..1000. This also adds a check and modifies the behavior to return an error code. Before this patch invalid values were ignored. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Alexey Dobriyan <[email protected]> Acked-by: Christoph Lameter <[email protected]> Cc: Pekka Enberg <[email protected]> Cc: David Rientjes <[email protected]> Cc: Joonsoo Kim <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
olifre · Apr 6, 2018 · eb7235e · eb7235e
1 parent ac914d0
commit eb7235e
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Showing 2 changed files with 7 additions and 6 deletions.
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
@@ -124,7 +124,7 @@ struct kmem_cache {
 	/*
 	 * Defragmentation by allocating from a remote node.
 	 */
-	int remote_node_defrag_ratio;
+	unsigned int remote_node_defrag_ratio;
 #endif
 
 #ifdef CONFIG_SLAB_FREELIST_RANDOM

diff --git a/mm/slub.c b/mm/slub.c
@@ -5289,21 +5289,22 @@ SLAB_ATTR(shrink);
 #ifdef CONFIG_NUMA
 static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf)
 {
-	return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10);
+	return sprintf(buf, "%u\n", s->remote_node_defrag_ratio / 10);
 }
 
 static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
 				const char *buf, size_t length)
 {
-	unsigned long ratio;
+	unsigned int ratio;
 	int err;
 
-	err = kstrtoul(buf, 10, &ratio);
+	err = kstrtouint(buf, 10, &ratio);
 	if (err)
 		return err;
+	if (ratio > 100)
+		return -ERANGE;
 
-	if (ratio <= 100)
-		s->remote_node_defrag_ratio = ratio * 10;
+	s->remote_node_defrag_ratio = ratio * 10;
 
 	return length;
 }