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[PATCH] Add 64bit jiffies compares (for use with get_jiffies_64)

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The current time_before/time_after macros will fail typechecks
when passed u64 values (as returned by get_jiffies_64()). On 64bit
systems, this will just result in a warning about mismatching types
without explicit casts, but since unsigned long and u64
(unsigned long long) are of same size, it will still work.
On 32bit systems, a long is 32bits, so the value from get_jiffies_64()
will be truncated by the cast and thus lose all the precision gained by
64bit jiffies.

Signed-off-by: Dmitriy Zavin <dmitriyz@google.com>
Signed-off-by: Andi Kleen <ak@suse.de>
This commit is contained in:
Dmitriy Zavin 2006-09-26 10:52:42 +02:00 committed by Andi Kleen
parent b89ebd0b0a
commit 3b17167283
1 changed files with 15 additions and 0 deletions
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15
include/linux/jiffies.h
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@ -115,6 +115,21 @@ static inline u64 get_jiffies_64(void)
((long)(a) - (long)(b) >= 0))
#define time_before_eq(a,b) time_after_eq(b,a)
/* Same as above, but does so with platform independent 64bit types.
* These must be used when utilizing jiffies_64 (i.e. return value of
* get_jiffies_64() */
#define time_after64(a,b) \
(typecheck(__u64, a) && \
typecheck(__u64, b) && \
((__s64)(b) - (__s64)(a) < 0))
#define time_before64(a,b) time_after64(b,a)
#define time_after_eq64(a,b) \
(typecheck(__u64, a) && \
typecheck(__u64, b) && \
((__s64)(a) - (__s64)(b) >= 0))
#define time_before_eq64(a,b) time_after_eq64(b,a)
/*
* Have the 32 bit jiffies value wrap 5 minutes after boot
* so jiffies wrap bugs show up earlier.