Set a bit and return its old value. Stolen from kernel
sources, will be used in next patches.
Cc: Adrian Hunter <adrian.hun...@intel.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Cc: David Ahern <dsah...@gmail.com>
Cc: Frederic Weisbecker <fweis...@gmail.com>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Namhyung Kim <namhy...@gmail.com>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Signed-off-by: Jiri Olsa <jo...@kernel.org>
---
tools/perf/util/include/linux/bitmap.h | 17 +++++++++++++++++
tools/perf/util/include/linux/bitops.h | 2 ++
2 files changed, 19 insertions(+)
diff --git a/tools/perf/util/include/linux/bitmap.h
b/tools/perf/util/include/linux/bitmap.h
index 01ffd12dc791..40bd21488032 100644
--- a/tools/perf/util/include/linux/bitmap.h
+++ b/tools/perf/util/include/linux/bitmap.h
@@ -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 */
diff --git a/tools/perf/util/include/linux/bitops.h
b/tools/perf/util/include/linux/bitops.h
index dadfa7e54287..c3294163de17 100644
--- a/tools/perf/util/include/linux/bitops.h
+++ b/tools/perf/util/include/linux/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)); \
--
1.9.3
--
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