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authorJiri Kosina <jkosina@suse.cz>2022-12-13 14:27:16 +0100
committerJiri Kosina <jkosina@suse.cz>2022-12-13 14:27:16 +0100
commitcfd1f6c16f7deadfe5269a76c1516405c4466481 (patch)
tree44c0635e57e9627d9838c0d0d5801381b93ccccd /include/linux/bitops.h
parenta9d9e46c755a189ccb44d91b8cf737742a975de8 (diff)
parentfd7b68b763c4dfa65e3c145c624427d5fd11202f (diff)
Merge branch 'for-6.2/apple' into for-linus
- new quirks for select Apple keyboards (Kerem Karabay, Aditya Garg)
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h30
1 files changed, 25 insertions, 5 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 3b89c64bcfd8..2ba557e067fe 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -248,6 +248,25 @@ static inline unsigned long __ffs64(u64 word)
}
/**
+ * fns - find N'th set bit in a word
+ * @word: The word to search
+ * @n: Bit to find
+ */
+static inline unsigned long fns(unsigned long word, unsigned int n)
+{
+ unsigned int bit;
+
+ while (word) {
+ bit = __ffs(word);
+ if (n-- == 0)
+ return bit;
+ __clear_bit(bit, &word);
+ }
+
+ return BITS_PER_LONG;
+}
+
+/**
* assign_bit - Assign value to a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
@@ -328,10 +347,10 @@ static __always_inline void __assign_bit(long nr, volatile unsigned long *addr,
const typeof(*(ptr)) mask__ = (mask), bits__ = (bits); \
typeof(*(ptr)) old__, new__; \
\
+ old__ = READ_ONCE(*(ptr)); \
do { \
- old__ = READ_ONCE(*(ptr)); \
new__ = (old__ & ~mask__) | bits__; \
- } while (cmpxchg(ptr, old__, new__) != old__); \
+ } while (!try_cmpxchg(ptr, &old__, new__)); \
\
old__; \
})
@@ -343,11 +362,12 @@ static __always_inline void __assign_bit(long nr, volatile unsigned long *addr,
const typeof(*(ptr)) clear__ = (clear), test__ = (test);\
typeof(*(ptr)) old__, new__; \
\
+ old__ = READ_ONCE(*(ptr)); \
do { \
- old__ = READ_ONCE(*(ptr)); \
+ if (old__ & test__) \
+ break; \
new__ = old__ & ~clear__; \
- } while (!(old__ & test__) && \
- cmpxchg(ptr, old__, new__) != old__); \
+ } while (!try_cmpxchg(ptr, &old__, new__)); \
\
!(old__ & test__); \
})