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authorIngo Molnar <mingo@elte.hu>2009-05-11 12:59:32 +0200
committerIngo Molnar <mingo@elte.hu>2009-05-11 12:59:37 +0200
commit7961386fe9596e6bf03d09948a73c5df9653325b (patch)
tree60fa2586a0d340ef8f7473956eef17430d8250c7 /include/linux/bitops.h
parentaa47b7e0f89b9998dad4d1667447e8cb7703ff4e (diff)
parent091bf7624d1c90cec9e578a18529f615213ff847 (diff)
Merge commit 'v2.6.30-rc5' into sched/core
Merge reason: sched/core was on .30-rc1 before, update to latest fixes Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 61829139795..c05a29cb9bb 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -112,6 +112,25 @@ static inline unsigned fls_long(unsigned long l)
return fls64(l);
}
+/**
+ * __ffs64 - find first set bit in a 64 bit word
+ * @word: The 64 bit word
+ *
+ * On 64 bit arches this is a synomyn for __ffs
+ * The result is not defined if no bits are set, so check that @word
+ * is non-zero before calling this.
+ */
+static inline unsigned long __ffs64(u64 word)
+{
+#if BITS_PER_LONG == 32
+ if (((u32)word) == 0UL)
+ return __ffs((u32)(word >> 32)) + 32;
+#elif BITS_PER_LONG != 64
+#error BITS_PER_LONG not 32 or 64
+#endif
+ return __ffs((unsigned long)word);
+}
+
#ifdef __KERNEL__
#ifdef CONFIG_GENERIC_FIND_FIRST_BIT