diff options
| author | Dan Carpenter <dan.carpenter@linaro.org> | 2024-06-11 15:38:12 +0300 |
|---|---|---|
| committer | Yury Norov <yury.norov@gmail.com> | 2024-06-18 10:40:53 -0700 |
| commit | e0eeb938adb0367de4b0946125a06142d8de7d37 (patch) | |
| tree | 7c68b4127479cdc18cb65f8e9b696b20628a1e3a /include/linux/bitops.h | |
| parent | e334771d83ec14f755a554394162198a955e3faa (diff) | |
bitops: Add a comment explaining the double underscore macros
Linus Walleij pointed out that a new comer might be confused about the
difference between set_bit() and __set_bit(). Add a comment explaining
the difference.
Link: https://lore.kernel.org/all/CACRpkdZFPG_YLici-BmYfk9HZ36f4WavCN3JNotkk8cPgCODCg@mail.gmail.com/
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Diffstat (limited to 'include/linux/bitops.h')
| -rw-r--r-- | include/linux/bitops.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h index 46d4bdc634c0..ba35bbf07798 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -47,12 +47,17 @@ extern unsigned long __sw_hweight64(__u64 w); __builtin_constant_p(*(const unsigned long *)(addr))) ? \ const##op(nr, addr) : op(nr, addr)) +/* + * The following macros are non-atomic versions of their non-underscored + * counterparts. + */ #define __set_bit(nr, addr) bitop(___set_bit, nr, addr) #define __clear_bit(nr, addr) bitop(___clear_bit, nr, addr) #define __change_bit(nr, addr) bitop(___change_bit, nr, addr) #define __test_and_set_bit(nr, addr) bitop(___test_and_set_bit, nr, addr) #define __test_and_clear_bit(nr, addr) bitop(___test_and_clear_bit, nr, addr) #define __test_and_change_bit(nr, addr) bitop(___test_and_change_bit, nr, addr) + #define test_bit(nr, addr) bitop(_test_bit, nr, addr) #define test_bit_acquire(nr, addr) bitop(_test_bit_acquire, nr, addr) |