diff options
Diffstat (limited to 'arch/sparc64/lib/rwsem.S')
| -rw-r--r-- | arch/sparc64/lib/rwsem.S | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/sparc64/lib/rwsem.S b/arch/sparc64/lib/rwsem.S new file mode 100644 index 00000000000..174ff7b9164 --- /dev/null +++ b/arch/sparc64/lib/rwsem.S @@ -0,0 +1,165 @@ +/* rwsem.S: RW semaphore assembler. + * + * Written by David S. Miller (davem@redhat.com), 2001. + * Derived from asm-i386/rwsem.h + */ + +#include <asm/rwsem-const.h> + + .section .sched.text + + .globl __down_read +__down_read: +1: lduw [%o0], %g1 + add %g1, 1, %g7 + cas [%o0], %g1, %g7 + cmp %g1, %g7 + bne,pn %icc, 1b + add %g7, 1, %g7 + cmp %g7, 0 + bl,pn %icc, 3f + membar #StoreLoad | #StoreStore +2: + retl + nop +3: + save %sp, -192, %sp + call rwsem_down_read_failed + mov %i0, %o0 + ret + restore + .size __down_read, .-__down_read + + .globl __down_read_trylock +__down_read_trylock: +1: lduw [%o0], %g1 + add %g1, 1, %g7 + cmp %g7, 0 + bl,pn %icc, 2f + mov 0, %o1 + cas [%o0], %g1, %g7 + cmp %g1, %g7 + bne,pn %icc, 1b + mov 1, %o1 + membar #StoreLoad | #StoreStore +2: retl + mov %o1, %o0 + .size __down_read_trylock, .-__down_read_trylock + + .globl __down_write +__down_write: + sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1 + or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1 +1: + lduw [%o0], %g3 + add %g3, %g1, %g7 + cas [%o0], %g3, %g7 + cmp %g3, %g7 + bne,pn %icc, 1b + cmp %g7, 0 + bne,pn %icc, 3f + membar #StoreLoad | #StoreStore +2: retl + nop +3: + save %sp, -192, %sp + call rwsem_down_write_failed + mov %i0, %o0 + ret + restore + .size __down_write, .-__down_write + + .globl __down_write_trylock +__down_write_trylock: + sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1 + or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1 +1: + lduw [%o0], %g3 + cmp %g3, 0 + bne,pn %icc, 2f + mov 0, %o1 + add %g3, %g1, %g7 + cas [%o0], %g3, %g7 + cmp %g3, %g7 + bne,pn %icc, 1b + mov 1, %o1 + membar #StoreLoad | #StoreStore +2: retl + mov %o1, %o0 + .size __down_write_trylock, .-__down_write_trylock + + .globl __up_read +__up_read: +1: + lduw [%o0], %g1 + sub %g1, 1, %g7 + cas [%o0], %g1, %g7 + cmp %g1, %g7 + bne,pn %icc, 1b + cmp %g7, 0 + bl,pn %icc, 3f + membar #StoreLoad | #StoreStore +2: retl + nop +3: sethi %hi(RWSEM_ACTIVE_MASK), %g1 + sub %g7, 1, %g7 + or %g1, %lo(RWSEM_ACTIVE_MASK), %g1 + andcc %g7, %g1, %g0 + bne,pn %icc, 2b + nop + save %sp, -192, %sp + call rwsem_wake + mov %i0, %o0 + ret + restore + .size __up_read, .-__up_read + + .globl __up_write +__up_write: + sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1 + or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1 +1: + lduw [%o0], %g3 + sub %g3, %g1, %g7 + cas [%o0], %g3, %g7 + cmp %g3, %g7 + bne,pn %icc, 1b + sub %g7, %g1, %g7 + cmp %g7, 0 + bl,pn %icc, 3f + membar #StoreLoad | #StoreStore +2: + retl + nop +3: + save %sp, -192, %sp + call rwsem_wake + mov %i0, %o0 + ret + restore + .size __up_write, .-__up_write + + .globl __downgrade_write +__downgrade_write: + sethi %hi(RWSEM_WAITING_BIAS), %g1 + or %g1, %lo(RWSEM_WAITING_BIAS), %g1 +1: + lduw [%o0], %g3 + sub %g3, %g1, %g7 + cas [%o0], %g3, %g7 + cmp %g3, %g7 + bne,pn %icc, 1b + sub %g7, %g1, %g7 + cmp %g7, 0 + bl,pn %icc, 3f + membar #StoreLoad | #StoreStore +2: + retl + nop +3: + save %sp, -192, %sp + call rwsem_downgrade_wake + mov %i0, %o0 + ret + restore + .size __downgrade_write, .-__downgrade_write |