tools lib: Add bitmap_and function

Add support to perform logical and on bitmaps.  Code taken from kernel's
include/linux/bitmap.h.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1470074555-24889-4-git-send-email-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/include/linux/bitmap.h

@@ -11,6 +11,8 @@
 int __bitmap_weight(const unsigned long *bitmap, int bits);
 void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
 		 const unsigned long *bitmap2, int bits);
+int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
+		 const unsigned long *bitmap2, unsigned int bits);
 
 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
 
@@ -85,4 +87,19 @@ static inline unsigned long *bitmap_alloc(int nbits)
 size_t bitmap_scnprintf(unsigned long *bitmap, int nbits,
 			char *buf, size_t size);
 
+/**
+ * bitmap_and - Do logical and on bitmaps
+ * @dst: resulting bitmap
+ * @src1: operand 1
+ * @src2: operand 2
+ * @nbits: size of bitmap
+ */
+static inline int bitmap_and(unsigned long *dst, const unsigned long *src1,
+			     const unsigned long *src2, unsigned int nbits)
+{
+	if (small_const_nbits(nbits))
+		return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
+	return __bitmap_and(dst, src1, src2, nbits);
+}
+
 #endif /* _PERF_BITOPS_H */

tools/lib/bitmap.c

@@ -58,3 +58,18 @@ size_t bitmap_scnprintf(unsigned long *bitmap, int nbits,
 	}
 	return ret;
 }
+
+int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
+		 const unsigned long *bitmap2, unsigned int bits)
+{
+	unsigned int k;
+	unsigned int lim = bits/BITS_PER_LONG;
+	unsigned long result = 0;
+
+	for (k = 0; k < lim; k++)
+		result |= (dst[k] = bitmap1[k] & bitmap2[k]);
+	if (bits % BITS_PER_LONG)
+		result |= (dst[k] = bitmap1[k] & bitmap2[k] &
+			   BITMAP_LAST_WORD_MASK(bits));
+	return result != 0;
+}