diff options
Diffstat (limited to 'libc/arch-arm/bionic/atomics_arm.S')
| -rw-r--r-- | libc/arch-arm/bionic/atomics_arm.S | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/libc/arch-arm/bionic/atomics_arm.S b/libc/arch-arm/bionic/atomics_arm.S index 55c642f..5076fe3 100644 --- a/libc/arch-arm/bionic/atomics_arm.S +++ b/libc/arch-arm/bionic/atomics_arm.S @@ -43,6 +43,19 @@ #define FUTEX_WAIT 0 #define FUTEX_WAKE 1 +/* Private futexes belong to a single address space and cannot be + * shared among processes. They are however significantly faster to + * operate than standard futexes. + */ +.global __futex_wait_private +.type __futex_wait_private, %function +.global __futex_wake_private +.type __futex_wake_private, %function + +#define FUTEX_PRIVATE_FLAG 128 +#define FUTEX_WAIT_PRIVATE (FUTEX_WAIT|FUTEX_PRIVATE_FLAG) +#define FUTEX_WAKE_PRIVATE (FUTEX_WAKE|FUTEX_PRIVATE_FLAG) + #if 1 .equ kernel_cmpxchg, 0xFFFF0FC0 .equ kernel_atomic_base, 0xFFFF0FFF @@ -185,6 +198,28 @@ __futex_wake: ldmia sp!, {r4, r7} bx lr +__futex_wait_private: + .fnstart + stmdb sp!, {r4, r7} + .save {r4, r7} + mov r3, r2 + mov r2, r1 + mov r1, #FUTEX_WAIT_PRIVATE + ldr r7, =__NR_futex + swi #0 + ldmia sp!, {r4, r7} + bx lr + .fnend + +__futex_wake_private: + stmdb sp!, {r4, r7} + mov r2, r1 + mov r1, #FUTEX_WAKE_PRIVATE + ldr r7, =__NR_futex + swi #0 + ldmia sp!, {r4, r7} + bx lr + #else __futex_wait: @@ -200,4 +235,17 @@ __futex_wake: swi #__NR_futex bx lr +__futex_wait_private: + mov r3, r2 + mov r2, r1 + mov r1, #FUTEX_WAIT_PRIVATE + swi #__NR_futex + bx lr + +__futex_wake_private: + mov r2, r1 + mov r1, #FUTEX_WAKE_PRIVATE + swi #__NR_futex + bx lr + #endif |