Commit 416c419c authored by Jiri Olsa's avatar Jiri Olsa Committed by Arnaldo Carvalho de Melo

perf tools: Add test_and_set_bit function

Set a bit and return its old value. Stolen from kernel sources, will be
used in next patches.
Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Acked-by: default avatarNamhyung Kim <namhyung@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1414363445-22370-1-git-send-email-jolsa@kernel.orgSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 96d78059
......@@ -46,4 +46,21 @@ static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
__bitmap_or(dst, src1, src2, nbits);
}
/**
* test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*/
static inline int test_and_set_bit(int nr, unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
unsigned long old;
old = *p;
*p = old | mask;
return (old & mask) != 0;
}
#endif /* _PERF_BITOPS_H */
......@@ -15,6 +15,8 @@
#define BITS_TO_U64(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
#define BITS_TO_U32(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
#define BITS_TO_BYTES(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE)
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
#define for_each_set_bit(bit, addr, size) \
for ((bit) = find_first_bit((addr), (size)); \
......
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