lib/sort.c optimization

Hello, I fixed and tested a small bug in lib/sort.c file, heap sort
function.

The fix avoids unnecessary swap of contents when i is 0 (saves few loads
and stores), which happens every time sort function is called.  I felt the
fix is worth bringing it to your attention given the importance and
frequent use of the sort function.

Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/sort.c b/lib/sort.c
index 961567894d1..6abbaf3d585 100644
--- a/lib/sort.c
+++ b/lib/sort.c
@@ -67,7 +67,7 @@ void sort(void *base, size_t num, size_t size,
         }
 
         /* sort */
-        for (i = n - size; i >= 0; i -= size) {
+        for (i = n - size; i > 0; i -= size) {
                 swap(base, base + i, size);
                 for (r = 0; r * 2 + size < i; r = c) {
                         c = r * 2 + size;