diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/x86_64/cancellation.S')
| -rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/x86_64/cancellation.S | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/x86_64/cancellation.S b/REORG.TODO/sysdeps/unix/sysv/linux/x86_64/cancellation.S new file mode 100644 index 0000000000..ed804df138 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/x86_64/cancellation.S @@ -0,0 +1,115 @@ +/* Copyright (C) 2009-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2009. + + 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 + <http://www.gnu.org/licenses/>. */ + +#include <sysdep.h> +#include <tcb-offsets.h> +#include <kernel-features.h> +#include "lowlevellock.h" + +#define PTHREAD_UNWIND JUMPTARGET(__pthread_unwind) +#if IS_IN (libpthread) +# if defined SHARED && !defined NO_HIDDEN +# undef PTHREAD_UNWIND +# define PTHREAD_UNWIND __GI___pthread_unwind +# endif +#else +# ifndef SHARED + .weak __pthread_unwind +# endif +#endif + + +#ifdef __ASSUME_PRIVATE_FUTEX +# define LOAD_PRIVATE_FUTEX_WAIT(reg) \ + movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg +#else +# if FUTEX_WAIT == 0 +# define LOAD_PRIVATE_FUTEX_WAIT(reg) \ + movl %fs:PRIVATE_FUTEX, reg +# else +# define LOAD_PRIVATE_FUTEX_WAIT(reg) \ + movl %fs:PRIVATE_FUTEX, reg ; \ + orl $FUTEX_WAIT, reg +# endif +#endif + +/* It is crucial that the functions in this file don't modify registers + other than %rax and %r11. The syscall wrapper code depends on this + because it doesn't explicitly save the other registers which hold + relevant values. */ + .text + + .hidden __pthread_enable_asynccancel +ENTRY(__pthread_enable_asynccancel) + movl %fs:CANCELHANDLING, %eax +2: movl %eax, %r11d + orl $TCB_CANCELTYPE_BITMASK, %r11d + cmpl %eax, %r11d + je 1f + + lock + cmpxchgl %r11d, %fs:CANCELHANDLING + jnz 2b + + andl $(TCB_CANCELSTATE_BITMASK|TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK|TCB_EXITING_BITMASK|TCB_CANCEL_RESTMASK|TCB_TERMINATED_BITMASK), %r11d + cmpl $(TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK), %r11d + je 3f + +1: ret + +3: subq $8, %rsp + cfi_adjust_cfa_offset(8) + LP_OP(mov) $TCB_PTHREAD_CANCELED, %fs:RESULT + lock + orl $TCB_EXITING_BITMASK, %fs:CANCELHANDLING + mov %fs:CLEANUP_JMP_BUF, %RDI_LP + call PTHREAD_UNWIND + hlt +END(__pthread_enable_asynccancel) + + + .hidden __pthread_disable_asynccancel +ENTRY(__pthread_disable_asynccancel) + testl $TCB_CANCELTYPE_BITMASK, %edi + jnz 1f + + movl %fs:CANCELHANDLING, %eax +2: movl %eax, %r11d + andl $~TCB_CANCELTYPE_BITMASK, %r11d + lock + cmpxchgl %r11d, %fs:CANCELHANDLING + jnz 2b + + movl %r11d, %eax +3: andl $(TCB_CANCELING_BITMASK|TCB_CANCELED_BITMASK), %eax + cmpl $TCB_CANCELING_BITMASK, %eax + je 4f +1: ret + + /* Performance doesn't matter in this loop. We will + delay until the thread is canceled. And we will unlikely + enter the loop twice. */ +4: mov %fs:0, %RDI_LP + movl $__NR_futex, %eax + xorq %r10, %r10 + addq $CANCELHANDLING, %rdi + LOAD_PRIVATE_FUTEX_WAIT (%esi) + syscall + movl %fs:CANCELHANDLING, %eax + jmp 3b +END(__pthread_disable_asynccancel) |