1c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes/* 2c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * Copyright (C) 2008 The Android Open Source Project 3c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * All rights reserved. 4c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * 5c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * Redistribution and use in source and binary forms, with or without 6c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * modification, are permitted provided that the following conditions 7c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * are met: 8c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * * Redistributions of source code must retain the above copyright 9c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * notice, this list of conditions and the following disclaimer. 10c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * * Redistributions in binary form must reproduce the above copyright 11c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * notice, this list of conditions and the following disclaimer in 12c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * the documentation and/or other materials provided with the 13c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * distribution. 14c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * 15c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * SUCH DAMAGE. 27c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes */ 28c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 29c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes#include <pthread.h> 30c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 3161fb3fc770566c7bafe7af8fb93590bcad387fbbElliott Hughes#include <signal.h> 32c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes#include <stdlib.h> 33f86c4494ff9613dcdf3dd7713d1e2c5d989d8ebaElliott Hughes#include <string.h> 34c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes#include <sys/mman.h> 35c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 36c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes#include "pthread_internal.h" 37c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 386203e7b853a587fbd70cea2e58b63ae38a71a13eElliott Hughesextern "C" __noreturn void _exit_with_stack_teardown(void*, size_t); 396203e7b853a587fbd70cea2e58b63ae38a71a13eElliott Hughesextern "C" __noreturn void __exit(int); 40101fb7d963ed362c4e351d95e55cbd70dc59eac3Christopher Ferrisextern "C" int __set_tid_address(int*); 41df79c330d895af31f39ee301dee62731fa586168Dmitriy Ivanovextern "C" void __cxa_thread_finalize(); 42c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 43c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes/* CAVEAT: our implementation of pthread_cleanup_push/pop doesn't support C++ exceptions 44c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes * and thread cancelation 45c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes */ 46c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 47c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughesvoid __pthread_cleanup_push(__pthread_cleanup_t* c, __pthread_cleanup_func_t routine, void* arg) { 48c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes pthread_internal_t* thread = __get_thread(); 49c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes c->__cleanup_routine = routine; 50c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes c->__cleanup_arg = arg; 51c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes c->__cleanup_prev = thread->cleanup_stack; 52c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes thread->cleanup_stack = c; 53c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes} 54c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 55c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughesvoid __pthread_cleanup_pop(__pthread_cleanup_t* c, int execute) { 56c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes pthread_internal_t* thread = __get_thread(); 57c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes thread->cleanup_stack = c->__cleanup_prev; 58c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes if (execute) { 59c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes c->__cleanup_routine(c->__cleanup_arg); 60c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes } 61c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes} 62c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 63877ec6d90418ff1d6597147d355a2229fdffae7eElliott Hughesvoid pthread_exit(void* return_value) { 64df79c330d895af31f39ee301dee62731fa586168Dmitriy Ivanov // Call dtors for thread_local objects first. 65df79c330d895af31f39ee301dee62731fa586168Dmitriy Ivanov __cxa_thread_finalize(); 66df79c330d895af31f39ee301dee62731fa586168Dmitriy Ivanov 67c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes pthread_internal_t* thread = __get_thread(); 68877ec6d90418ff1d6597147d355a2229fdffae7eElliott Hughes thread->return_value = return_value; 69c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 70df79c330d895af31f39ee301dee62731fa586168Dmitriy Ivanov // Call the cleanup handlers. 71c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes while (thread->cleanup_stack) { 72c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes __pthread_cleanup_t* c = thread->cleanup_stack; 73c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes thread->cleanup_stack = c->__cleanup_prev; 74c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes c->__cleanup_routine(c->__cleanup_arg); 75c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes } 76c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 77c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes // Call the TLS destructors. It is important to do that before removing this 78c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes // thread from the global list. This will ensure that if someone else deletes 79c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes // a TLS key, the corresponding value will be set to NULL in this thread's TLS 80c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes // space (see pthread_key_delete). 81c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes pthread_key_clean_all(); 82c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 83c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes if (thread->alternate_signal_stack != NULL) { 84c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes // Tell the kernel to stop using the alternate signal stack. 852c6c95348ca9df1727fd7402b3704e0e87cb347eElliott Hughes stack_t ss; 862c6c95348ca9df1727fd7402b3704e0e87cb347eElliott Hughes memset(&ss, 0, sizeof(ss)); 87c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes ss.ss_flags = SS_DISABLE; 88c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes sigaltstack(&ss, NULL); 89c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 90c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes // Free it. 91ef115003012f61cf5539fdfeb201b98e4a92f610Yabin Cui munmap(thread->alternate_signal_stack, SIGNAL_STACK_SIZE); 92c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes thread->alternate_signal_stack = NULL; 93c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes } 94c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes 955450f86b31287173278513eb8b4c8e73b9fdd3aeJosh Gao // Unmap the bionic TLS, including guard pages. 965450f86b31287173278513eb8b4c8e73b9fdd3aeJosh Gao void* allocation = reinterpret_cast<char*>(thread->bionic_tls) - PAGE_SIZE; 975450f86b31287173278513eb8b4c8e73b9fdd3aeJosh Gao munmap(allocation, BIONIC_TLS_SIZE + 2 * PAGE_SIZE); 985450f86b31287173278513eb8b4c8e73b9fdd3aeJosh Gao 9958cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui ThreadJoinState old_state = THREAD_NOT_JOINED; 10058cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui while (old_state == THREAD_NOT_JOINED && 10158cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui !atomic_compare_exchange_weak(&thread->join_state, &old_state, THREAD_EXITED_NOT_JOINED)) { 10258cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui } 10358cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui 10458cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui if (old_state == THREAD_DETACHED) { 105ba8dfc2669d658dc340eb8f9c9b40ca074f05047Yabin Cui // The thread is detached, no one will use pthread_internal_t after pthread_exit. 106ba8dfc2669d658dc340eb8f9c9b40ca074f05047Yabin Cui // So we can free mapped space, which includes pthread_internal_t and thread stack. 107960ee37f2aaf52bbec2f6265fd6e30fb2b41fef3Elliott Hughes // First make sure that the kernel does not try to clear the tid field 108960ee37f2aaf52bbec2f6265fd6e30fb2b41fef3Elliott Hughes // because we'll have freed the memory before the thread actually exits. 109101fb7d963ed362c4e351d95e55cbd70dc59eac3Christopher Ferris __set_tid_address(NULL); 1108cf1b305670123aed7638d984ca39bfd22388440Yabin Cui 1117484c21c4c352a2200d94939fabc10d1bd3f0723Elliott Hughes // pthread_internal_t is freed below with stack, not here. 1127484c21c4c352a2200d94939fabc10d1bd3f0723Elliott Hughes __pthread_internal_remove(thread); 1137484c21c4c352a2200d94939fabc10d1bd3f0723Elliott Hughes 11458cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui if (thread->mmap_size != 0) { 11558cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui // We need to free mapped space for detached threads when they exit. 11658cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui // That's not something we can do in C. 11758cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui 11858cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui // We don't want to take a signal after we've unmapped the stack. 11958cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui // That's one last thing we can handle in C. 12058cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui sigset_t mask; 12158cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui sigfillset(&mask); 12258cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui sigprocmask(SIG_SETMASK, &mask, NULL); 12358cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui 12458cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui _exit_with_stack_teardown(thread->attr.stack_base, thread->mmap_size); 12558cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui } 126c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes } 12758cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui 12858cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui // No need to free mapped space. Either there was no space mapped, or it is left for 12958cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui // the pthread_join caller to clean up. 13058cf31b50699ed9f523de38c8e943f3bbd1ced9eYabin Cui __exit(0); 131c3f114037dbf028896310609fd28cf2b3da99c4dElliott Hughes} 132