summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--lib/string.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/lib/string.c b/lib/string.c
index 77bd0b1d3296..b2de45a581f4 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -29,6 +29,7 @@
#include <linux/errno.h>
#include <linux/slab.h>
+#include <asm/unaligned.h>
#include <asm/byteorder.h>
#include <asm/word-at-a-time.h>
#include <asm/page.h>
@@ -935,6 +936,21 @@ __visible int memcmp(const void *cs, const void *ct, size_t count)
const unsigned char *su1, *su2;
int res = 0;
+#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+ if (count >= sizeof(unsigned long)) {
+ const unsigned long *u1 = cs;
+ const unsigned long *u2 = ct;
+ do {
+ if (get_unaligned(u1) != get_unaligned(u2))
+ break;
+ u1++;
+ u2++;
+ count -= sizeof(unsigned long);
+ } while (count >= sizeof(unsigned long));
+ cs = u1;
+ ct = u2;
+ }
+#endif
for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
if ((res = *su1 - *su2) != 0)
break;