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Subject[patch] time_after_eq fix
Hello,

The two macros time_after and time_after_eq were added to do wrapping
correctly, but only time_after does it the right way, time_after_eq has
been wrong since the very beginning(v2.1.127, 07-Nov-1998). Now this
patch fixes it.

And I don't agree with the the original code comment. I don't think this
is gcc's fault. If it is "a good compiler" or "a really good compiler",
trying to be smarter than human, it wouldn't still be a C compiler.
So I'd like it be removed.

Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org>
---
jiffies.h | 6 ++----
1 files changed, 2 insertions(+), 4 deletions(-)
diff -pruN 2.6.12-rc4-mm2/include/linux/jiffies.h 2.6.12-rc4-mm2-cy/include/linux/jiffies.h
--- 2.6.12-rc4-mm2/include/linux/jiffies.h 2005-03-03 17:12:13.000000000 +0800
+++ 2.6.12-rc4-mm2-cy/include/linux/jiffies.h 2005-05-19 05:32:52.000000000 +0800
@@ -102,9 +102,7 @@ static inline u64 get_jiffies_64(void)
*
* time_after(a,b) returns true if the time a is after time b.
*
- * Do this with "<0" and ">=0" to only test the sign of the result. A
- * good compiler would generate better code (and a really good compiler
- * wouldn't care). Gcc is currently neither.
+ * Do this with "<0" and "<=0" to only test the sign of the result.
*/
#define time_after(a,b) \
(typecheck(unsigned long, a) && \
@@ -115,7 +113,7 @@ static inline u64 get_jiffies_64(void)
#define time_after_eq(a,b) \
(typecheck(unsigned long, a) && \
typecheck(unsigned long, b) && \
- ((long)(a) - (long)(b) >= 0))
+ ((long)(b) - (long)(a) <= 0))
#define time_before_eq(a,b) time_after_eq(b,a)

/*
-
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