Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
"One more fix from the timer departement:
- Handle division of negative nanosecond values proper on 32bit.
A recent cleanup wrecked the sign handling of the dividend and
dropped the check for negative divisors"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ktime: Fix ktime_divns to do signed division
+29
-12
+21
-6
include/linux/ktime.h
+21
-6
include/linux/ktime.h
···
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}
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#if BITS_PER_LONG < 64
169
-
extern u64 __ktime_divns(const ktime_t kt, s64 div);
170
-
static inline u64 ktime_divns(const ktime_t kt, s64 div)
169
+
extern s64 __ktime_divns(const ktime_t kt, s64 div);
170
+
static inline s64 ktime_divns(const ktime_t kt, s64 div)
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{
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+
/*
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+
* Negative divisors could cause an inf loop,
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+
* so bug out here.
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+
*/
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+
BUG_ON(div < 0);
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if (__builtin_constant_p(div) && !(div >> 32)) {
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-
u64 ns = kt.tv64;
174
-
do_div(ns, div);
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-
return ns;
178
+
s64 ns = kt.tv64;
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+
u64 tmp = ns < 0 ? -ns : ns;
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+
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+
do_div(tmp, div);
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+
return ns < 0 ? -tmp : tmp;
176
183
} else {
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184
return __ktime_divns(kt, div);
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}
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}
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#else /* BITS_PER_LONG < 64 */
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-
# define ktime_divns(kt, div) (u64)((kt).tv64 / (div))
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+
static inline s64 ktime_divns(const ktime_t kt, s64 div)
189
+
{
190
+
/*
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+
* 32-bit implementation cannot handle negative divisors,
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+
* so catch them on 64bit as well.
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+
*/
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+
WARN_ON(div < 0);
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+
return kt.tv64 / div;
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+
}
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#endif
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199
static inline s64 ktime_to_us(const ktime_t kt)
+8
-6
kernel/time/hrtimer.c
+8
-6
kernel/time/hrtimer.c
···
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/*
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* Divide a ktime value by a nanosecond value
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*/
269
-
u64 __ktime_divns(const ktime_t kt, s64 div)
269
+
s64 __ktime_divns(const ktime_t kt, s64 div)
270
270
{
271
-
u64 dclc;
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271
int sft = 0;
272
+
s64 dclc;
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+
u64 tmp;
273
274
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275
dclc = ktime_to_ns(kt);
276
+
tmp = dclc < 0 ? -dclc : dclc;
277
+
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/* Make sure the divisor is less than 2^32: */
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while (div >> 32) {
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sft++;
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div >>= 1;
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282
}
280
-
dclc >>= sft;
281
-
do_div(dclc, (unsigned long) div);
282
-
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-
return dclc;
283
+
tmp >>= sft;
284
+
do_div(tmp, (unsigned long) div);
285
+
return dclc < 0 ? -tmp : tmp;
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286
}
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EXPORT_SYMBOL_GPL(__ktime_divns);
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288
#endif /* BITS_PER_LONG >= 64 */