1 /* Copyright (C) 2009-2016 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2009.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
20 #include <tcb-offsets.h>
21 #include <kernel-features.h>
22 #include "lowlevellock.h"
24 #define PTHREAD_UNWIND JUMPTARGET(__pthread_unwind)
25 #if IS_IN (libpthread)
26 # if defined SHARED && !defined NO_HIDDEN
27 # undef PTHREAD_UNWIND
28 # define PTHREAD_UNWIND __GI___pthread_unwind
32 .weak __pthread_unwind
37 #ifdef __ASSUME_PRIVATE_FUTEX
38 # define LOAD_PRIVATE_FUTEX_WAIT(reg) \
39 movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
42 # define LOAD_PRIVATE_FUTEX_WAIT(reg) \
43 movl %fs:PRIVATE_FUTEX, reg
45 # define LOAD_PRIVATE_FUTEX_WAIT(reg) \
46 movl %fs:PRIVATE_FUTEX, reg ; \
51 /* It is crucial that the functions in this file don't modify registers
52 other than %rax and %r11. The syscall wrapper code depends on this
53 because it doesn't explicitly save the other registers which hold
57 .hidden __pthread_enable_asynccancel
58 ENTRY(__pthread_enable_asynccancel)
59 movl %fs:CANCELHANDLING, %eax
61 orl $TCB_CANCELTYPE_BITMASK, %r11d
66 cmpxchgl %r11d, %fs:CANCELHANDLING
69 andl $(TCB_CANCELSTATE_BITMASK|TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK|TCB_EXITING_BITMASK|TCB_CANCEL_RESTMASK|TCB_TERMINATED_BITMASK), %r11d
70 cmpl $(TCB_CANCELTYPE_BITMASK|TCB_CANCELED_BITMASK), %r11d
76 cfi_adjust_cfa_offset(8)
77 LP_OP(mov) $TCB_PTHREAD_CANCELED, %fs:RESULT
79 orl $TCB_EXITING_BITMASK, %fs:CANCELHANDLING
80 mov %fs:CLEANUP_JMP_BUF, %RDI_LP
83 END(__pthread_enable_asynccancel)
86 .hidden __pthread_disable_asynccancel
87 ENTRY(__pthread_disable_asynccancel)
88 testl $TCB_CANCELTYPE_BITMASK, %edi
91 movl %fs:CANCELHANDLING, %eax
93 andl $~TCB_CANCELTYPE_BITMASK, %r11d
95 cmpxchgl %r11d, %fs:CANCELHANDLING
99 3: andl $(TCB_CANCELING_BITMASK|TCB_CANCELED_BITMASK), %eax
100 cmpl $TCB_CANCELING_BITMASK, %eax
104 /* Performance doesn't matter in this loop. We will
105 delay until the thread is canceled. And we will unlikely
106 enter the loop twice. */
107 4: mov %fs:0, %RDI_LP
108 movl $__NR_futex, %eax
110 addq $CANCELHANDLING, %rdi
111 LOAD_PRIVATE_FUTEX_WAIT (%esi)
113 movl %fs:CANCELHANDLING, %eax
115 END(__pthread_disable_asynccancel)