diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_wrlock.S')
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_wrlock.S | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_wrlock.S b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_wrlock.S index be6b8d8e20..63fc2dfd91 100644 --- a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_wrlock.S +++ b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_wrlock.S @@ -31,6 +31,94 @@ .align 16 __pthread_rwlock_wrlock: cfi_startproc + movq NRW_WORD(%rdi), %rax +.Lagain: + movq $(NRW_WW_MASK|NRW_WL|NRW_RC_MASK), %rdx + testq %rdx, %rax + jnz .Lwait + + // XXX Probably make AR a don't-care for !WP. Unconditionally set it + movq $(NRW_AR|NRW_WL), %rdx + movq $NRW_WL, %rcx + testq $NRW_WP, %rax + cmovz %rcx, %rdx + orq %rax, %rdx + LOCK + cmpxchgq %rdx, NRW_WORD(%rdi) + jnz .Lagain + + movl %fs:TID, %eax + movl %eax, WRITER(%rdi) + + xorl %eax, %eax + ret + +.Lwait: movq $NRW_WL, %rcx + testq %rcx, %rax + jz 1f + + movl %fs:TID, %eax + cmpl %eax, WRITER(%rdi) + je .Ldeadlk + +1: leaq NRW_WORD+4(%rdi), %rdi + + movq $NRW_WW, %rdx + movq $NRW_WW_MASK, %rcx + addq %rax, %rdx + testq %rcx, %rdx + jz .Lovfl + + LOCK + cmpxchgq %rdx, -4(%rdi) + jnz .Lagain + + xorq %r10, %r10 + movl $NRW_W_WAKEUP, %r9d +.Lwait2: + movl $(FUTEX_WAIT_BITSET|FUTEX_PRIVATE_FLAG), %esi + movl $__NR_futex, %eax + xorl PSHARED-(NRW_WORD+4)(%rdi), %esi + syscall + movq -4(%rdi), %rax + +.Lagain2: + movq $(NRW_WL|NRW_RC_MASK), %rdx + movq $(NRW_WL|NRW_AR), %rcx + testq %rdx, %rax + movq $NRW_AR, %rsi + setz %cl + andq %rax, %rcx + cmpq %rsi, %rcx + sete %cl + orb %dl, %cl + jz .Lwait2 + + movq $-NRW_WW, %rdx + addq %rax, %rdx + xorl %ecx, %ecx + testq $NRW_WP, %rax + cmovz %rcx, %rsi + orq %rsi, %rdx + + LOCK + cmpxchgq %rdx, -4(%rdi) + jnz .Lagain2 + + movl %fs:TID, %eax + movl %eax, WRITER(%rdi) + + xorl %eax, %eax + ret + +.Lovfl: movl $EAGAIN, %eax + ret + +.Ldeadlk: + movl $EDEADLK, %eax + ret + +#if 0 xorq %r10, %r10 /* Get the lock. */ @@ -156,6 +244,7 @@ __pthread_rwlock_wrlock: subq $MUTEX, %rdi #endif jmp 13b +#endif cfi_endproc .size __pthread_rwlock_wrlock,.-__pthread_rwlock_wrlock |