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authorLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 14:56:31 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-02 14:56:31 -0700
commit0279b3c0ada1d78882f24acf94ac4595bd657a89 (patch)
treeba31505ea6581b840604493d0233857bb7ce58d1 /lib
parent797994f81a8b2bdca2eecffa415c1e7a89a4f961 (diff)
parentf3002134158092178be81339ec5a22ff80e6c308 (diff)
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar: "This fixes the cputime scaling overflow problems for good without having bad 32-bit overhead, and gets rid of the div64_u64_rem() helper as well." * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "math64: New div64_u64_rem helper" sched: Avoid prev->stime underflow sched: Do not account bogus utime sched: Avoid cputime scaling overflow
Diffstat (limited to 'lib')
-rw-r--r--lib/div64.c19
1 files changed, 6 insertions, 13 deletions
diff --git a/lib/div64.c b/lib/div64.c
index 3af5728d95fd..a163b6caef73 100644
--- a/lib/div64.c
+++ b/lib/div64.c
@@ -79,10 +79,9 @@ EXPORT_SYMBOL(div_s64_rem);
#endif
/**
- * div64_u64_rem - unsigned 64bit divide with 64bit divisor and 64bit remainder
+ * div64_u64 - unsigned 64bit divide with 64bit divisor
* @dividend: 64bit dividend
* @divisor: 64bit divisor
- * @remainder: 64bit remainder
*
* This implementation is a modified version of the algorithm proposed
* by the book 'Hacker's Delight'. The original source and full proof
@@ -90,33 +89,27 @@ EXPORT_SYMBOL(div_s64_rem);
*
* 'http://www.hackersdelight.org/HDcode/newCode/divDouble.c.txt'
*/
-#ifndef div64_u64_rem
-u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder)
+#ifndef div64_u64
+u64 div64_u64(u64 dividend, u64 divisor)
{
u32 high = divisor >> 32;
u64 quot;
if (high == 0) {
- u32 rem32;
- quot = div_u64_rem(dividend, divisor, &rem32);
- *remainder = rem32;
+ quot = div_u64(dividend, divisor);
} else {
int n = 1 + fls(high);
quot = div_u64(dividend >> n, divisor >> n);
if (quot != 0)
quot--;
-
- *remainder = dividend - quot * divisor;
- if (*remainder >= divisor) {
+ if ((dividend - quot * divisor) >= divisor)
quot++;
- *remainder -= divisor;
- }
}
return quot;
}
-EXPORT_SYMBOL(div64_u64_rem);
+EXPORT_SYMBOL(div64_u64);
#endif
/**