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authorIngo Molnar <mingo@kernel.org>2016-07-08 11:51:28 +0200
committerIngo Molnar <mingo@kernel.org>2016-07-08 11:51:28 +0200
commit946e0f6ffcaa614012d646f4cf84efdd62628c8b (patch)
tree37d31fd748f98ec4fb7897997a2745228bf0c2da /include/linux/bitops.h
parent67d7a982bab6702d84415ea889996fae72a7d3b2 (diff)
parenta99cde438de0c4c0cecc1d1af1a55a75b10bfdef (diff)
Merge tag 'v4.7-rc6' into x86/mm, to merge fixes before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h16
1 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index defeaac0745f..299e76b59fe9 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -227,6 +227,22 @@ static inline unsigned long __ffs64(u64 word)
})
#endif
+#ifndef bit_clear_unless
+#define bit_clear_unless(ptr, _clear, _test) \
+({ \
+ const typeof(*ptr) clear = (_clear), test = (_test); \
+ typeof(*ptr) old, new; \
+ \
+ do { \
+ old = ACCESS_ONCE(*ptr); \
+ new = old & ~clear; \
+ } while (!(old & test) && \
+ cmpxchg(ptr, old, new) != old); \
+ \
+ !(old & test); \
+})
+#endif
+
#ifndef find_last_bit
/**
* find_last_bit - find the last set bit in a memory region