提交 ff80a77f 编写于 作者: M Mike Galbraith 提交者: Ingo Molnar

sched: simplify sched_find_first_bit()

simplify sched_rt.c's sched_find_first_bit() function: there are
only 100 RT priority levels left.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
上级 5e7eaade
......@@ -6,28 +6,23 @@
/*
* Every architecture must define this function. It's the fastest
* way of searching a 140-bit bitmap where the first 100 bits are
* unlikely to be set. It's guaranteed that at least one of the 140
* bits is cleared.
* way of searching a 100-bit bitmap. It's guaranteed that at least
* one of the 100 bits is cleared.
*/
static inline int sched_find_first_bit(const unsigned long *b)
{
#if BITS_PER_LONG == 64
if (unlikely(b[0]))
if (b[0])
return __ffs(b[0]);
if (likely(b[1]))
return __ffs(b[1]) + 64;
return __ffs(b[2]) + 128;
return __ffs(b[1]) + 64;
#elif BITS_PER_LONG == 32
if (unlikely(b[0]))
if (b[0])
return __ffs(b[0]);
if (unlikely(b[1]))
if (b[1])
return __ffs(b[1]) + 32;
if (unlikely(b[2]))
if (b[2])
return __ffs(b[2]) + 64;
if (b[3])
return __ffs(b[3]) + 96;
return __ffs(b[4]) + 128;
return __ffs(b[3]) + 96;
#else
#error BITS_PER_LONG not defined
#endif
......
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