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Subject[PATCH v8 09/22] tools lib: Introduce bitmap_intersects() operation
Date
Introduce bitmap_intersects() routine that tests whether
bitmaps bitmap1 and bitmap2 intersects. This routine will
be used during thread masks initialization.

Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
---
tools/include/linux/bitmap.h | 11 +++++++++++
tools/lib/bitmap.c | 14 ++++++++++++++
2 files changed, 25 insertions(+)

diff --git a/tools/include/linux/bitmap.h b/tools/include/linux/bitmap.h
index 330dbf7509cc..9d959bc24859 100644
--- a/tools/include/linux/bitmap.h
+++ b/tools/include/linux/bitmap.h
@@ -18,6 +18,8 @@ int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
int __bitmap_equal(const unsigned long *bitmap1,
const unsigned long *bitmap2, unsigned int bits);
void bitmap_clear(unsigned long *map, unsigned int start, int len);
+int __bitmap_intersects(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int bits);

#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
@@ -170,4 +172,13 @@ static inline int bitmap_equal(const unsigned long *src1,
return __bitmap_equal(src1, src2, nbits);
}

+static inline int bitmap_intersects(const unsigned long *src1,
+ const unsigned long *src2, unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
+ else
+ return __bitmap_intersects(src1, src2, nbits);
+}
+
#endif /* _PERF_BITOPS_H */
diff --git a/tools/lib/bitmap.c b/tools/lib/bitmap.c
index f4e914712b6f..db466ef7be9d 100644
--- a/tools/lib/bitmap.c
+++ b/tools/lib/bitmap.c
@@ -86,3 +86,17 @@ int __bitmap_equal(const unsigned long *bitmap1,

return 1;
}
+
+int __bitmap_intersects(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int bits)
+{
+ unsigned int k, lim = bits/BITS_PER_LONG;
+ for (k = 0; k < lim; ++k)
+ if (bitmap1[k] & bitmap2[k])
+ return 1;
+
+ if (bits % BITS_PER_LONG)
+ if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
+ return 1;
+ return 0;
+}
--
2.19.0
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