* Linus Torvalds <[EMAIL PROTECTED]> wrote: > I can do ppc64 myself, can others fix the other architectures (Ingo, > shouldn't the UP case have the read/write_can_lock() cases too? And > wouldn't you agree that it makes more sense to have the rwlock test > variants in asm/rwlock.h?):
(untested) ia64 version below. Differs from x86/x64. Ingo Signed-off-by: Ingo Molnar <[EMAIL PROTECTED]> --- linux/include/asm-ia64/spinlock.h.orig +++ linux/include/asm-ia64/spinlock.h @@ -128,8 +128,27 @@ typedef struct { #define RW_LOCK_UNLOCKED (rwlock_t) { 0, 0 } #define rwlock_init(x) do { *(x) = RW_LOCK_UNLOCKED; } while(0) -#define rwlock_is_locked(x) (*(volatile int *) (x) != 0) +/** + * read_can_lock - would read_trylock() succeed? + * @lock: the rwlock in question. + */ +static inline int read_can_lock(rwlock_t *rw) +{ + return *(volatile int *)rw >= 0; +} + +/** + * write_can_lock - would write_trylock() succeed? + * @lock: the rwlock in question. + */ +static inline int write_can_lock(rwlock_t *rw) +{ + return *(volatile int *)rw == 0; +} + + /* + * On x86, we implement read-write locks as a 32-bit counter #define _raw_read_lock(rw) \ do { \ rwlock_t *__read_lock_ptr = (rw); \ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/