Messages in this thread Patch in this message | | | Date | Thu, 10 May 2007 15:58:32 +0300 | From | Mika Kukkonen <> | Subject | [PATCH] Fix bug in mm/thrash.c function grab_swap_token() |
| |
Following bug was uncovered by compiling with '-W' flag:
CC mm/thrash.o mm/thrash.c: In function ‘grab_swap_token’: mm/thrash.c:52: warning: comparison of unsigned expression < 0 is always false
Field token_priority is unsigned, so decrementing first and the checking is not a good plan. Attached patch (compile tested) reverses the order.
Btw, I'm not sure if likely() makes any sense in this new situation.
Signed-off-by: Mika Kukkonen <mikukkon@iki.fi>
diff --git a/mm/thrash.c b/mm/thrash.c index 9ef9071..c4c5205 100644 --- a/mm/thrash.c +++ b/mm/thrash.c @@ -48,9 +48,8 @@ void grab_swap_token(void) if (current_interval < current->mm->last_interval) current->mm->token_priority++; else { - current->mm->token_priority--; - if (unlikely(current->mm->token_priority < 0)) - current->mm->token_priority = 0; + if (likely(current->mm->token_priority > 0)) + current->mm->token_priority--; } /* Check if we deserve the token */ if (current->mm->token_priority > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |