bitmap: introduce bitmap_count_one()
Count how many bits set in the bitmap.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
diff --git a/util/bitmap.c b/util/bitmap.c
index efced9a..90a42ff 100644
--- a/util/bitmap.c
+++ b/util/bitmap.c
@@ -355,3 +355,18 @@
}
return 0;
}
+
+long slow_bitmap_count_one(const unsigned long *bitmap, long nbits)
+{
+ long k, lim = nbits / BITS_PER_LONG, result = 0;
+
+ for (k = 0; k < lim; k++) {
+ result += ctpopl(bitmap[k]);
+ }
+
+ if (nbits % BITS_PER_LONG) {
+ result += ctpopl(bitmap[k] & BITMAP_LAST_WORD_MASK(nbits));
+ }
+
+ return result;
+}
