Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
timers: Simplify calc_index()
The level granularity round up of calc_index() does:
(x + (1 << n)) >> n
which is obviously equivalent to
(x >> n) + 1
but compilers can't figure that out despite the fact that the input range
is known to not cause an overflow. It's neither intuitive to read.
Just write out the obvious.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/87h778j46c.ffs@tglx
+1
-1
+1
-1
kernel/time/timer.c
+1
-1
kernel/time/timer.c
···
502
502
*
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503
* Round up with level granularity to prevent this.
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*/
505
-
expires = (expires + LVL_GRAN(lvl)) >> LVL_SHIFT(lvl);
505
+
expires = (expires >> LVL_SHIFT(lvl)) + 1;
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*bucket_expiry = expires << LVL_SHIFT(lvl);
507
507
return LVL_OFFS(lvl) + (expires & LVL_MASK);
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508
}