diff options
| author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-10-20 00:10:27 -0300 |
|---|---|---|
| committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-10-20 00:10:27 -0300 |
| commit | d0b2f91bede3bd5e3d24dd6803e56eee959c1797 (patch) | |
| tree | 7fee4ab0509879c373c4f2cbd5b8a5be5b4041ee /include/asm-generic/qrwlock.h | |
| parent | e914f8eb445e8f74b00303c19c2ffceaedd16a05 (diff) | |
Linux-libre 4.8.2-gnupck-4.8.2-gnu
Diffstat (limited to 'include/asm-generic/qrwlock.h')
| -rw-r--r-- | include/asm-generic/qrwlock.h | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/include/asm-generic/qrwlock.h b/include/asm-generic/qrwlock.h index 54a8e65e1..7d026bf27 100644 --- a/include/asm-generic/qrwlock.h +++ b/include/asm-generic/qrwlock.h @@ -25,7 +25,20 @@ #include <asm-generic/qrwlock_types.h> /* - * Writer states & reader shift and bias + * Writer states & reader shift and bias. + * + * | +0 | +1 | +2 | +3 | + * ----+----+----+----+----+ + * LE | 78 | 56 | 34 | 12 | 0x12345678 + * ----+----+----+----+----+ + * | wr | rd | + * +----+----+----+----+ + * + * ----+----+----+----+----+ + * BE | 12 | 34 | 56 | 78 | 0x12345678 + * ----+----+----+----+----+ + * | rd | wr | + * +----+----+----+----+ */ #define _QW_WAITING 1 /* A writer is waiting */ #define _QW_LOCKED 0xff /* A writer holds the lock */ @@ -134,12 +147,22 @@ static inline void queued_read_unlock(struct qrwlock *lock) } /** + * __qrwlock_write_byte - retrieve the write byte address of a queue rwlock + * @lock : Pointer to queue rwlock structure + * Return: the write byte address of a queue rwlock + */ +static inline u8 *__qrwlock_write_byte(struct qrwlock *lock) +{ + return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN); +} + +/** * queued_write_unlock - release write lock of a queue rwlock * @lock : Pointer to queue rwlock structure */ static inline void queued_write_unlock(struct qrwlock *lock) { - smp_store_release((u8 *)&lock->cnts, 0); + smp_store_release(__qrwlock_write_byte(lock), 0); } /* |