/* Copyright (C) 2002-2005, 2007, 2009 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 2002. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see . */ #include #include #include #include #include #include /* For the calculation see asm/vsyscall.h. */ #define VSYSCALL_ADDR_vgettimeofday 0xffffffffff600000 .text .globl pthread_rwlock_timedrdlock .type pthread_rwlock_timedrdlock,@function .align 16 pthread_rwlock_timedrdlock: cfi_startproc pushq %r12 cfi_adjust_cfa_offset(8) cfi_rel_offset(%r12, 0) pushq %r13 cfi_adjust_cfa_offset(8) cfi_rel_offset(%r13, 0) #ifdef __ASSUME_FUTEX_CLOCK_REALTIME # define VALREG %edx #else pushq %r14 cfi_adjust_cfa_offset(8) cfi_rel_offset(%r14, 0) subq $16, %rsp cfi_adjust_cfa_offset(16) # define VALREG %r14d #endif movq %rdi, %r12 movq %rsi, %r13 /* Get the lock. */ movl $1, %esi xorl %eax, %eax LOCK #if MUTEX == 0 cmpxchgl %esi, (%rdi) #else cmpxchgl %esi, MUTEX(%rdi) #endif jnz 1f 2: movl WRITER(%r12), %eax testl %eax, %eax jne 14f cmpl $0, WRITERS_QUEUED(%r12) je 5f cmpl $0, FLAGS(%r12) je 5f /* Check the value of the timeout parameter. */ 3: cmpq $1000000000, 8(%r13) jae 19f incl READERS_QUEUED(%r12) je 4f movl READERS_WAKEUP(%r12), VALREG /* Unlock. */ LOCK #if MUTEX == 0 decl (%r12) #else decl MUTEX(%r12) #endif jne 10f 11: #ifndef __ASSUME_FUTEX_CLOCK_REALTIME # ifdef __PIC__ cmpl $0, __have_futex_clock_realtime@GOTOFF(%rip) # else cmpl $0, __have_futex_clock_realtime # endif je .Lreltmo #endif movl $FUTEX_PRIVATE_FLAG|FUTEX_WAIT_BITSET|FUTEX_CLOCK_REALTIME, %esi xorl PSHARED(%r12), %esi movq %r13, %r10 movl $0xffffffff, %r9d #ifndef __ASSUME_FUTEX_CLOCK_REALTIME movl %r14d, %edx #endif 21: leaq READERS_WAKEUP(%r12), %rdi movl $SYS_futex, %eax syscall movq %rax, %rdx #ifndef __ASSUME_FUTEX_CLOCK_REALTIME .subsection 2 .Lreltmo: /* Get current time. */ movq %rsp, %rdi xorl %esi, %esi movq $VSYSCALL_ADDR_vgettimeofday, %rax callq *%rax /* Compute relative timeout. */ movq 8(%rsp), %rax movl $1000, %edi mul %rdi /* Milli seconds to nano seconds. */ movq (%r13), %rcx movq 8(%r13), %rdi subq (%rsp), %rcx subq %rax, %rdi jns 15f addq $1000000000, %rdi decq %rcx 15: testq %rcx, %rcx js 16f /* Time is already up. */ /* Futex call. */ movq %rcx, (%rsp) /* Store relative timeout. */ movq %rdi, 8(%rsp) # ifdef __ASSUME_PRIVATE_FUTEX movl $FUTEX_PRIVATE_FLAG|FUTEX_WAIT, %esi xorl PSHARED(%r12), %esi # else # if FUTEX_WAIT == 0 movl PSHARED(%r12), %esi # else movl $FUTEX_WAIT, %esi orl PSHARED(%r12), %esi # endif xorl %fs:PRIVATE_FUTEX, %esi # endif movq %rsp, %r10 movl %r14d, %edx jmp 21b .previous #endif 17: /* Reget the lock. */ movl $1, %esi xorl %eax, %eax LOCK #if MUTEX == 0 cmpxchgl %esi, (%r12) #else cmpxchgl %esi, MUTEX(%r12) #endif jnz 12f 13: decl READERS_QUEUED(%r12) cmpq $-ETIMEDOUT, %rdx jne 2b 18: movl $ETIMEDOUT, %edx jmp 9f 5: xorl %edx, %edx incl NR_READERS(%r12) je 8f 9: LOCK #if MUTEX == 0 decl (%r12) #else decl MUTEX(%r12) #endif jne 6f 7: movq %rdx, %rax #ifndef __ASSUME_FUTEX_CLOCK_REALTIME addq $16, %rsp cfi_adjust_cfa_offset(-16) popq %r14 cfi_adjust_cfa_offset(-8) cfi_restore(%r14) #endif popq %r13 cfi_adjust_cfa_offset(-8) cfi_restore(%r13) popq %r12 cfi_adjust_cfa_offset(-8) cfi_restore(%r12) retq #ifdef __ASSUME_PRIVATE_FUTEX cfi_adjust_cfa_offset(16) cfi_rel_offset(%r12, 8) cfi_rel_offset(%r13, 0) #else cfi_adjust_cfa_offset(40) cfi_offset(%r12, -16) cfi_offset(%r13, -24) cfi_offset(%r14, -32) #endif 1: movl PSHARED(%rdi), %esi #if MUTEX != 0 addq $MUTEX, %rdi #endif callq __lll_lock_wait jmp 2b 14: cmpl %fs:TID, %eax jne 3b movl $EDEADLK, %edx jmp 9b 6: movl PSHARED(%r12), %esi #if MUTEX == 0 movq %r12, %rdi #else leal MUTEX(%r12), %rdi #endif callq __lll_unlock_wake jmp 7b /* Overflow. */ 8: decl NR_READERS(%r12) movl $EAGAIN, %edx jmp 9b /* Overflow. */ 4: decl READERS_QUEUED(%r12) movl $EAGAIN, %edx jmp 9b 10: movl PSHARED(%r12), %esi #if MUTEX == 0 movq %r12, %rdi #else leaq MUTEX(%r12), %rdi #endif callq __lll_unlock_wake jmp 11b 12: movl PSHARED(%r12), %esi #if MUTEX == 0 movq %r12, %rdi #else leaq MUTEX(%r12), %rdi #endif callq __lll_lock_wait jmp 13b 16: movq $-ETIMEDOUT, %rdx jmp 17b 19: movl $EINVAL, %edx jmp 9b cfi_endproc .size pthread_rwlock_timedrdlock,.-pthread_rwlock_timedrdlock