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-rw-r--r--tools/lib/find_bit.c143
1 files changed, 71 insertions, 72 deletions
diff --git a/tools/lib/find_bit.c b/tools/lib/find_bit.c
index ac37022e9486..6a3dc167d30e 100644
--- a/tools/lib/find_bit.c
+++ b/tools/lib/find_bit.c
@@ -18,74 +18,74 @@
#include <linux/bitmap.h>
#include <linux/kernel.h>
-#if !defined(find_next_bit) || !defined(find_next_zero_bit) || \
- !defined(find_next_and_bit)
-
/*
- * This is a common helper function for find_next_bit, find_next_zero_bit, and
- * find_next_and_bit. The differences are:
- * - The "invert" argument, which is XORed with each fetched word before
- * searching it for one bits.
- * - The optional "addr2", which is anded with "addr1" if present.
+ * Common helper for find_bit() function family
+ * @FETCH: The expression that fetches and pre-processes each word of bitmap(s)
+ * @MUNGE: The expression that post-processes a word containing found bit (may be empty)
+ * @size: The bitmap size in bits
*/
-static inline unsigned long _find_next_bit(const unsigned long *addr1,
- const unsigned long *addr2, unsigned long nbits,
- unsigned long start, unsigned long invert)
-{
- unsigned long tmp;
-
- if (unlikely(start >= nbits))
- return nbits;
-
- tmp = addr1[start / BITS_PER_LONG];
- if (addr2)
- tmp &= addr2[start / BITS_PER_LONG];
- tmp ^= invert;
-
- /* Handle 1st word. */
- tmp &= BITMAP_FIRST_WORD_MASK(start);
- start = round_down(start, BITS_PER_LONG);
-
- while (!tmp) {
- start += BITS_PER_LONG;
- if (start >= nbits)
- return nbits;
-
- tmp = addr1[start / BITS_PER_LONG];
- if (addr2)
- tmp &= addr2[start / BITS_PER_LONG];
- tmp ^= invert;
- }
+#define FIND_FIRST_BIT(FETCH, MUNGE, size) \
+({ \
+ unsigned long idx, val, sz = (size); \
+ \
+ for (idx = 0; idx * BITS_PER_LONG < sz; idx++) { \
+ val = (FETCH); \
+ if (val) { \
+ sz = min(idx * BITS_PER_LONG + __ffs(MUNGE(val)), sz); \
+ break; \
+ } \
+ } \
+ \
+ sz; \
+})
- return min(start + __ffs(tmp), nbits);
-}
-#endif
+/*
+ * Common helper for find_next_bit() function family
+ * @FETCH: The expression that fetches and pre-processes each word of bitmap(s)
+ * @MUNGE: The expression that post-processes a word containing found bit (may be empty)
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ */
+#define FIND_NEXT_BIT(FETCH, MUNGE, size, start) \
+({ \
+ unsigned long mask, idx, tmp, sz = (size), __start = (start); \
+ \
+ if (unlikely(__start >= sz)) \
+ goto out; \
+ \
+ mask = MUNGE(BITMAP_FIRST_WORD_MASK(__start)); \
+ idx = __start / BITS_PER_LONG; \
+ \
+ for (tmp = (FETCH) & mask; !tmp; tmp = (FETCH)) { \
+ if ((idx + 1) * BITS_PER_LONG >= sz) \
+ goto out; \
+ idx++; \
+ } \
+ \
+ sz = min(idx * BITS_PER_LONG + __ffs(MUNGE(tmp)), sz); \
+out: \
+ sz; \
+})
-#ifndef find_next_bit
+#ifndef find_first_bit
/*
- * Find the next set bit in a memory region.
+ * Find the first set bit in a memory region.
*/
-unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
- unsigned long offset)
+unsigned long _find_first_bit(const unsigned long *addr, unsigned long size)
{
- return _find_next_bit(addr, NULL, size, offset, 0UL);
+ return FIND_FIRST_BIT(addr[idx], /* nop */, size);
}
#endif
-#ifndef find_first_bit
+#ifndef find_first_and_bit
/*
- * Find the first set bit in a memory region.
+ * Find the first set bit in two memory regions.
*/
-unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
+unsigned long _find_first_and_bit(const unsigned long *addr1,
+ const unsigned long *addr2,
+ unsigned long size)
{
- unsigned long idx;
-
- for (idx = 0; idx * BITS_PER_LONG < size; idx++) {
- if (addr[idx])
- return min(idx * BITS_PER_LONG + __ffs(addr[idx]), size);
- }
-
- return size;
+ return FIND_FIRST_BIT(addr1[idx] & addr2[idx], /* nop */, size);
}
#endif
@@ -93,32 +93,31 @@ unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
/*
* Find the first cleared bit in a memory region.
*/
-unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
+unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size)
{
- unsigned long idx;
-
- for (idx = 0; idx * BITS_PER_LONG < size; idx++) {
- if (addr[idx] != ~0UL)
- return min(idx * BITS_PER_LONG + ffz(addr[idx]), size);
- }
-
- return size;
+ return FIND_FIRST_BIT(~addr[idx], /* nop */, size);
}
#endif
-#ifndef find_next_zero_bit
-unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
- unsigned long offset)
+#ifndef find_next_bit
+unsigned long _find_next_bit(const unsigned long *addr, unsigned long nbits, unsigned long start)
{
- return _find_next_bit(addr, NULL, size, offset, ~0UL);
+ return FIND_NEXT_BIT(addr[idx], /* nop */, nbits, start);
}
#endif
#ifndef find_next_and_bit
-unsigned long find_next_and_bit(const unsigned long *addr1,
- const unsigned long *addr2, unsigned long size,
- unsigned long offset)
+unsigned long _find_next_and_bit(const unsigned long *addr1, const unsigned long *addr2,
+ unsigned long nbits, unsigned long start)
+{
+ return FIND_NEXT_BIT(addr1[idx] & addr2[idx], /* nop */, nbits, start);
+}
+#endif
+
+#ifndef find_next_zero_bit
+unsigned long _find_next_zero_bit(const unsigned long *addr, unsigned long nbits,
+ unsigned long start)
{
- return _find_next_bit(addr1, addr2, size, offset, 0UL);
+ return FIND_NEXT_BIT(~addr[idx], /* nop */, nbits, start);
}
#endif