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776 lines
23 KiB
C
776 lines
23 KiB
C
/* Copyright (C) 2002-2015 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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#include <ctype.h>
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#include <errno.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdint.h>
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#include "pthreadP.h"
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#include <hp-timing.h>
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#include <ldsodefs.h>
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#include <atomic.h>
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#include <libc-internal.h>
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#include <resolv.h>
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#include <kernel-features.h>
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#include <exit-thread.h>
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#include <default-sched.h>
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#include <shlib-compat.h>
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#include <stap-probe.h>
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/* Nozero if debugging mode is enabled. */
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int __pthread_debug;
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/* Globally enabled events. */
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static td_thr_events_t __nptl_threads_events __attribute_used__;
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/* Pointer to descriptor with the last event. */
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static struct pthread *__nptl_last_event __attribute_used__;
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/* Number of threads running. */
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unsigned int __nptl_nthreads = 1;
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/* Code to allocate and deallocate a stack. */
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#include "allocatestack.c"
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/* createthread.c defines this function, and two macros:
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START_THREAD_DEFN and START_THREAD_SELF (see below).
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create_thread is obliged to initialize PD->stopped_start. It
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should be true if the STOPPED_START parameter is true, or if
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create_thread needs the new thread to synchronize at startup for
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some other implementation reason. If PD->stopped_start will be
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true, then create_thread is obliged to perform the operation
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"lll_lock (PD->lock, LLL_PRIVATE)" before starting the thread.
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The return value is zero for success or an errno code for failure.
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If the return value is ENOMEM, that will be translated to EAGAIN,
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so create_thread need not do that. On failure, *THREAD_RAN should
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be set to true iff the thread actually started up and then got
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cancelled before calling user code (*PD->start_routine), in which
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case it is responsible for doing its own cleanup. */
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static int create_thread (struct pthread *pd, const struct pthread_attr *attr,
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bool stopped_start, STACK_VARIABLES_PARMS,
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bool *thread_ran);
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#include <createthread.c>
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struct pthread *
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internal_function
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__find_in_stack_list (pd)
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struct pthread *pd;
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{
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list_t *entry;
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struct pthread *result = NULL;
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lll_lock (stack_cache_lock, LLL_PRIVATE);
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list_for_each (entry, &stack_used)
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{
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struct pthread *curp;
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curp = list_entry (entry, struct pthread, list);
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if (curp == pd)
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{
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result = curp;
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break;
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}
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}
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if (result == NULL)
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list_for_each (entry, &__stack_user)
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{
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struct pthread *curp;
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curp = list_entry (entry, struct pthread, list);
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if (curp == pd)
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{
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result = curp;
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break;
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}
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}
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lll_unlock (stack_cache_lock, LLL_PRIVATE);
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return result;
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}
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/* Deallocate POSIX thread-local-storage. */
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void
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attribute_hidden
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__nptl_deallocate_tsd (void)
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{
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struct pthread *self = THREAD_SELF;
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/* Maybe no data was ever allocated. This happens often so we have
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a flag for this. */
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if (THREAD_GETMEM (self, specific_used))
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{
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size_t round;
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size_t cnt;
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round = 0;
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do
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{
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size_t idx;
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/* So far no new nonzero data entry. */
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THREAD_SETMEM (self, specific_used, false);
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for (cnt = idx = 0; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
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{
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struct pthread_key_data *level2;
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level2 = THREAD_GETMEM_NC (self, specific, cnt);
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if (level2 != NULL)
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{
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size_t inner;
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for (inner = 0; inner < PTHREAD_KEY_2NDLEVEL_SIZE;
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++inner, ++idx)
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{
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void *data = level2[inner].data;
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if (data != NULL)
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{
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/* Always clear the data. */
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level2[inner].data = NULL;
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/* Make sure the data corresponds to a valid
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key. This test fails if the key was
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deallocated and also if it was
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re-allocated. It is the user's
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responsibility to free the memory in this
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case. */
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if (level2[inner].seq
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== __pthread_keys[idx].seq
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/* It is not necessary to register a destructor
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function. */
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&& __pthread_keys[idx].destr != NULL)
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/* Call the user-provided destructor. */
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__pthread_keys[idx].destr (data);
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}
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}
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}
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else
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idx += PTHREAD_KEY_1STLEVEL_SIZE;
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}
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if (THREAD_GETMEM (self, specific_used) == 0)
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/* No data has been modified. */
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goto just_free;
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}
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/* We only repeat the process a fixed number of times. */
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while (__builtin_expect (++round < PTHREAD_DESTRUCTOR_ITERATIONS, 0));
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/* Just clear the memory of the first block for reuse. */
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memset (&THREAD_SELF->specific_1stblock, '\0',
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sizeof (self->specific_1stblock));
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just_free:
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/* Free the memory for the other blocks. */
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for (cnt = 1; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
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{
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struct pthread_key_data *level2;
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level2 = THREAD_GETMEM_NC (self, specific, cnt);
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if (level2 != NULL)
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{
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/* The first block is allocated as part of the thread
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descriptor. */
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free (level2);
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THREAD_SETMEM_NC (self, specific, cnt, NULL);
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}
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}
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THREAD_SETMEM (self, specific_used, false);
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}
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}
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/* Deallocate a thread's stack after optionally making sure the thread
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descriptor is still valid. */
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void
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internal_function
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__free_tcb (struct pthread *pd)
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{
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/* The thread is exiting now. */
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if (__builtin_expect (atomic_bit_test_set (&pd->cancelhandling,
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TERMINATED_BIT) == 0, 1))
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{
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/* Remove the descriptor from the list. */
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if (DEBUGGING_P && __find_in_stack_list (pd) == NULL)
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/* Something is really wrong. The descriptor for a still
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running thread is gone. */
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abort ();
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/* Free TPP data. */
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if (__glibc_unlikely (pd->tpp != NULL))
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{
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struct priority_protection_data *tpp = pd->tpp;
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pd->tpp = NULL;
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free (tpp);
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}
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/* Queue the stack memory block for reuse and exit the process. The
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kernel will signal via writing to the address returned by
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QUEUE-STACK when the stack is available. */
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__deallocate_stack (pd);
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}
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}
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/* Local function to start thread and handle cleanup.
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createthread.c defines the macro START_THREAD_DEFN to the
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declaration that its create_thread function will refer to, and
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START_THREAD_SELF to the expression to optimally deliver the new
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thread's THREAD_SELF value. */
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START_THREAD_DEFN
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{
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struct pthread *pd = START_THREAD_SELF;
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#if HP_TIMING_AVAIL
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/* Remember the time when the thread was started. */
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hp_timing_t now;
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HP_TIMING_NOW (now);
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THREAD_SETMEM (pd, cpuclock_offset, now);
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#endif
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/* Initialize resolver state pointer. */
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__resp = &pd->res;
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/* Initialize pointers to locale data. */
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__ctype_init ();
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/* Allow setxid from now onwards. */
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if (__glibc_unlikely (atomic_exchange_acq (&pd->setxid_futex, 0) == -2))
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lll_futex_wake (&pd->setxid_futex, 1, LLL_PRIVATE);
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#ifdef __NR_set_robust_list
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# ifndef __ASSUME_SET_ROBUST_LIST
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if (__set_robust_list_avail >= 0)
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# endif
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{
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INTERNAL_SYSCALL_DECL (err);
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/* This call should never fail because the initial call in init.c
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succeeded. */
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INTERNAL_SYSCALL (set_robust_list, err, 2, &pd->robust_head,
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sizeof (struct robust_list_head));
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}
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#endif
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#ifdef SIGCANCEL
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/* If the parent was running cancellation handlers while creating
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the thread the new thread inherited the signal mask. Reset the
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cancellation signal mask. */
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if (__glibc_unlikely (pd->parent_cancelhandling & CANCELING_BITMASK))
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{
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INTERNAL_SYSCALL_DECL (err);
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sigset_t mask;
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__sigemptyset (&mask);
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__sigaddset (&mask, SIGCANCEL);
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(void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &mask,
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NULL, _NSIG / 8);
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}
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#endif
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/* This is where the try/finally block should be created. For
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compilers without that support we do use setjmp. */
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struct pthread_unwind_buf unwind_buf;
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/* No previous handlers. */
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unwind_buf.priv.data.prev = NULL;
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unwind_buf.priv.data.cleanup = NULL;
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int not_first_call;
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not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf);
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if (__glibc_likely (! not_first_call))
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{
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/* Store the new cleanup handler info. */
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THREAD_SETMEM (pd, cleanup_jmp_buf, &unwind_buf);
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if (__glibc_unlikely (pd->stopped_start))
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{
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int oldtype = CANCEL_ASYNC ();
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/* Get the lock the parent locked to force synchronization. */
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lll_lock (pd->lock, LLL_PRIVATE);
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/* And give it up right away. */
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lll_unlock (pd->lock, LLL_PRIVATE);
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CANCEL_RESET (oldtype);
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}
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LIBC_PROBE (pthread_start, 3, (pthread_t) pd, pd->start_routine, pd->arg);
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/* Run the code the user provided. */
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#ifdef CALL_THREAD_FCT
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THREAD_SETMEM (pd, result, CALL_THREAD_FCT (pd));
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#else
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THREAD_SETMEM (pd, result, pd->start_routine (pd->arg));
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#endif
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}
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/* Call destructors for the thread_local TLS variables. */
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#ifndef SHARED
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if (&__call_tls_dtors != NULL)
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#endif
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__call_tls_dtors ();
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/* Run the destructor for the thread-local data. */
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__nptl_deallocate_tsd ();
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/* Clean up any state libc stored in thread-local variables. */
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__libc_thread_freeres ();
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/* If this is the last thread we terminate the process now. We
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do not notify the debugger, it might just irritate it if there
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is no thread left. */
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if (__glibc_unlikely (atomic_decrement_and_test (&__nptl_nthreads)))
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/* This was the last thread. */
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exit (0);
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/* Report the death of the thread if this is wanted. */
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if (__glibc_unlikely (pd->report_events))
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{
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/* See whether TD_DEATH is in any of the mask. */
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const int idx = __td_eventword (TD_DEATH);
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const uint32_t mask = __td_eventmask (TD_DEATH);
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if ((mask & (__nptl_threads_events.event_bits[idx]
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| pd->eventbuf.eventmask.event_bits[idx])) != 0)
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{
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/* Yep, we have to signal the death. Add the descriptor to
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the list but only if it is not already on it. */
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if (pd->nextevent == NULL)
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{
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pd->eventbuf.eventnum = TD_DEATH;
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pd->eventbuf.eventdata = pd;
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do
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pd->nextevent = __nptl_last_event;
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while (atomic_compare_and_exchange_bool_acq (&__nptl_last_event,
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pd, pd->nextevent));
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}
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/* Now call the function to signal the event. */
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__nptl_death_event ();
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}
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}
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/* The thread is exiting now. Don't set this bit until after we've hit
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the event-reporting breakpoint, so that td_thr_get_info on us while at
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the breakpoint reports TD_THR_RUN state rather than TD_THR_ZOMBIE. */
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atomic_bit_set (&pd->cancelhandling, EXITING_BIT);
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#ifndef __ASSUME_SET_ROBUST_LIST
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/* If this thread has any robust mutexes locked, handle them now. */
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# ifdef __PTHREAD_MUTEX_HAVE_PREV
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void *robust = pd->robust_head.list;
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# else
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__pthread_slist_t *robust = pd->robust_list.__next;
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# endif
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/* We let the kernel do the notification if it is able to do so.
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If we have to do it here there for sure are no PI mutexes involved
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since the kernel support for them is even more recent. */
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if (__set_robust_list_avail < 0
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&& __builtin_expect (robust != (void *) &pd->robust_head, 0))
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{
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do
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{
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struct __pthread_mutex_s *this = (struct __pthread_mutex_s *)
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((char *) robust - offsetof (struct __pthread_mutex_s,
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__list.__next));
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robust = *((void **) robust);
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# ifdef __PTHREAD_MUTEX_HAVE_PREV
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this->__list.__prev = NULL;
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# endif
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this->__list.__next = NULL;
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atomic_or (&this->__lock, FUTEX_OWNER_DIED);
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lll_futex_wake (&this->__lock, 1, /* XYZ */ LLL_SHARED);
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}
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while (robust != (void *) &pd->robust_head);
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}
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#endif
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/* Mark the memory of the stack as usable to the kernel. We free
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everything except for the space used for the TCB itself. */
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size_t pagesize_m1 = __getpagesize () - 1;
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#ifdef _STACK_GROWS_DOWN
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char *sp = CURRENT_STACK_FRAME;
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size_t freesize = (sp - (char *) pd->stackblock) & ~pagesize_m1;
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#else
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# error "to do"
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#endif
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assert (freesize < pd->stackblock_size);
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if (freesize > PTHREAD_STACK_MIN)
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__madvise (pd->stackblock, freesize - PTHREAD_STACK_MIN, MADV_DONTNEED);
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/* If the thread is detached free the TCB. */
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if (IS_DETACHED (pd))
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/* Free the TCB. */
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__free_tcb (pd);
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else if (__glibc_unlikely (pd->cancelhandling & SETXID_BITMASK))
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{
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/* Some other thread might call any of the setXid functions and expect
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us to reply. In this case wait until we did that. */
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do
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lll_futex_wait (&pd->setxid_futex, 0, LLL_PRIVATE);
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while (pd->cancelhandling & SETXID_BITMASK);
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/* Reset the value so that the stack can be reused. */
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pd->setxid_futex = 0;
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}
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/* We cannot call '_exit' here. '_exit' will terminate the process.
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The 'exit' implementation in the kernel will signal when the
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process is really dead since 'clone' got passed the CLONE_CHILD_CLEARTID
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flag. The 'tid' field in the TCB will be set to zero.
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The exit code is zero since in case all threads exit by calling
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'pthread_exit' the exit status must be 0 (zero). */
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__exit_thread ();
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/* NOTREACHED */
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}
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/* Return true iff obliged to report TD_CREATE events. */
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static bool
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report_thread_creation (struct pthread *pd)
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{
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if (__glibc_unlikely (THREAD_GETMEM (THREAD_SELF, report_events)))
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{
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/* The parent thread is supposed to report events.
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Check whether the TD_CREATE event is needed, too. */
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const size_t idx = __td_eventword (TD_CREATE);
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const uint32_t mask = __td_eventmask (TD_CREATE);
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return ((mask & (__nptl_threads_events.event_bits[idx]
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| pd->eventbuf.eventmask.event_bits[idx])) != 0);
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}
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return false;
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}
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int
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__pthread_create_2_1 (newthread, attr, start_routine, arg)
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pthread_t *newthread;
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const pthread_attr_t *attr;
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void *(*start_routine) (void *);
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void *arg;
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{
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STACK_VARIABLES;
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const struct pthread_attr *iattr = (struct pthread_attr *) attr;
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struct pthread_attr default_attr;
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bool free_cpuset = false;
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if (iattr == NULL)
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{
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lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
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default_attr = __default_pthread_attr;
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size_t cpusetsize = default_attr.cpusetsize;
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if (cpusetsize > 0)
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{
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cpu_set_t *cpuset;
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if (__glibc_likely (__libc_use_alloca (cpusetsize)))
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cpuset = __alloca (cpusetsize);
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else
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{
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cpuset = malloc (cpusetsize);
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if (cpuset == NULL)
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{
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lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
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return ENOMEM;
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}
|
||
free_cpuset = true;
|
||
}
|
||
memcpy (cpuset, default_attr.cpuset, cpusetsize);
|
||
default_attr.cpuset = cpuset;
|
||
}
|
||
lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
|
||
iattr = &default_attr;
|
||
}
|
||
|
||
struct pthread *pd = NULL;
|
||
int err = ALLOCATE_STACK (iattr, &pd);
|
||
int retval = 0;
|
||
|
||
if (__glibc_unlikely (err != 0))
|
||
/* Something went wrong. Maybe a parameter of the attributes is
|
||
invalid or we could not allocate memory. Note we have to
|
||
translate error codes. */
|
||
{
|
||
retval = err == ENOMEM ? EAGAIN : err;
|
||
goto out;
|
||
}
|
||
|
||
|
||
/* Initialize the TCB. All initializations with zero should be
|
||
performed in 'get_cached_stack'. This way we avoid doing this if
|
||
the stack freshly allocated with 'mmap'. */
|
||
|
||
#if TLS_TCB_AT_TP
|
||
/* Reference to the TCB itself. */
|
||
pd->header.self = pd;
|
||
|
||
/* Self-reference for TLS. */
|
||
pd->header.tcb = pd;
|
||
#endif
|
||
|
||
/* Store the address of the start routine and the parameter. Since
|
||
we do not start the function directly the stillborn thread will
|
||
get the information from its thread descriptor. */
|
||
pd->start_routine = start_routine;
|
||
pd->arg = arg;
|
||
|
||
/* Copy the thread attribute flags. */
|
||
struct pthread *self = THREAD_SELF;
|
||
pd->flags = ((iattr->flags & ~(ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET))
|
||
| (self->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET)));
|
||
|
||
/* Initialize the field for the ID of the thread which is waiting
|
||
for us. This is a self-reference in case the thread is created
|
||
detached. */
|
||
pd->joinid = iattr->flags & ATTR_FLAG_DETACHSTATE ? pd : NULL;
|
||
|
||
/* The debug events are inherited from the parent. */
|
||
pd->eventbuf = self->eventbuf;
|
||
|
||
|
||
/* Copy the parent's scheduling parameters. The flags will say what
|
||
is valid and what is not. */
|
||
pd->schedpolicy = self->schedpolicy;
|
||
pd->schedparam = self->schedparam;
|
||
|
||
/* Copy the stack guard canary. */
|
||
#ifdef THREAD_COPY_STACK_GUARD
|
||
THREAD_COPY_STACK_GUARD (pd);
|
||
#endif
|
||
|
||
/* Copy the pointer guard value. */
|
||
#ifdef THREAD_COPY_POINTER_GUARD
|
||
THREAD_COPY_POINTER_GUARD (pd);
|
||
#endif
|
||
|
||
/* Verify the sysinfo bits were copied in allocate_stack if needed. */
|
||
#ifdef NEED_DL_SYSINFO
|
||
CHECK_THREAD_SYSINFO (pd);
|
||
#endif
|
||
|
||
/* Inform start_thread (above) about cancellation state that might
|
||
translate into inherited signal state. */
|
||
pd->parent_cancelhandling = THREAD_GETMEM (THREAD_SELF, cancelhandling);
|
||
|
||
/* Determine scheduling parameters for the thread. */
|
||
if (__builtin_expect ((iattr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0, 0)
|
||
&& (iattr->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET)) != 0)
|
||
{
|
||
/* Use the scheduling parameters the user provided. */
|
||
if (iattr->flags & ATTR_FLAG_POLICY_SET)
|
||
{
|
||
pd->schedpolicy = iattr->schedpolicy;
|
||
pd->flags |= ATTR_FLAG_POLICY_SET;
|
||
}
|
||
if (iattr->flags & ATTR_FLAG_SCHED_SET)
|
||
{
|
||
/* The values were validated in pthread_attr_setschedparam. */
|
||
pd->schedparam = iattr->schedparam;
|
||
pd->flags |= ATTR_FLAG_SCHED_SET;
|
||
}
|
||
|
||
if ((pd->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET))
|
||
!= (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET))
|
||
collect_default_sched (pd);
|
||
}
|
||
|
||
/* Pass the descriptor to the caller. */
|
||
*newthread = (pthread_t) pd;
|
||
|
||
LIBC_PROBE (pthread_create, 4, newthread, attr, start_routine, arg);
|
||
|
||
/* One more thread. We cannot have the thread do this itself, since it
|
||
might exist but not have been scheduled yet by the time we've returned
|
||
and need to check the value to behave correctly. We must do it before
|
||
creating the thread, in case it does get scheduled first and then
|
||
might mistakenly think it was the only thread. In the failure case,
|
||
we momentarily store a false value; this doesn't matter because there
|
||
is no kosher thing a signal handler interrupting us right here can do
|
||
that cares whether the thread count is correct. */
|
||
atomic_increment (&__nptl_nthreads);
|
||
|
||
bool thread_ran = false;
|
||
|
||
/* Start the thread. */
|
||
if (__glibc_unlikely (report_thread_creation (pd)))
|
||
{
|
||
/* Create the thread. We always create the thread stopped
|
||
so that it does not get far before we tell the debugger. */
|
||
retval = create_thread (pd, iattr, true, STACK_VARIABLES_ARGS,
|
||
&thread_ran);
|
||
if (retval == 0)
|
||
{
|
||
/* create_thread should have set this so that the logic below can
|
||
test it. */
|
||
assert (pd->stopped_start);
|
||
|
||
/* Now fill in the information about the new thread in
|
||
the newly created thread's data structure. We cannot let
|
||
the new thread do this since we don't know whether it was
|
||
already scheduled when we send the event. */
|
||
pd->eventbuf.eventnum = TD_CREATE;
|
||
pd->eventbuf.eventdata = pd;
|
||
|
||
/* Enqueue the descriptor. */
|
||
do
|
||
pd->nextevent = __nptl_last_event;
|
||
while (atomic_compare_and_exchange_bool_acq (&__nptl_last_event,
|
||
pd, pd->nextevent)
|
||
!= 0);
|
||
|
||
/* Now call the function which signals the event. */
|
||
__nptl_create_event ();
|
||
}
|
||
}
|
||
else
|
||
retval = create_thread (pd, iattr, false, STACK_VARIABLES_ARGS,
|
||
&thread_ran);
|
||
|
||
if (__glibc_unlikely (retval != 0))
|
||
{
|
||
/* If thread creation "failed", that might mean that the thread got
|
||
created and ran a little--short of running user code--but then
|
||
create_thread cancelled it. In that case, the thread will do all
|
||
its own cleanup just like a normal thread exit after a successful
|
||
creation would do. */
|
||
|
||
if (thread_ran)
|
||
assert (pd->stopped_start);
|
||
else
|
||
{
|
||
/* Oops, we lied for a second. */
|
||
atomic_decrement (&__nptl_nthreads);
|
||
|
||
/* Perhaps a thread wants to change the IDs and is waiting for this
|
||
stillborn thread. */
|
||
if (__glibc_unlikely (atomic_exchange_acq (&pd->setxid_futex, 0)
|
||
== -2))
|
||
lll_futex_wake (&pd->setxid_futex, 1, LLL_PRIVATE);
|
||
|
||
/* Free the resources. */
|
||
__deallocate_stack (pd);
|
||
}
|
||
|
||
/* We have to translate error codes. */
|
||
if (retval == ENOMEM)
|
||
retval = EAGAIN;
|
||
}
|
||
else
|
||
{
|
||
if (pd->stopped_start)
|
||
/* The thread blocked on this lock either because we're doing TD_CREATE
|
||
event reporting, or for some other reason that create_thread chose.
|
||
Now let it run free. */
|
||
lll_unlock (pd->lock, LLL_PRIVATE);
|
||
|
||
/* We now have for sure more than one thread. The main thread might
|
||
not yet have the flag set. No need to set the global variable
|
||
again if this is what we use. */
|
||
THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1);
|
||
}
|
||
|
||
out:
|
||
if (__glibc_unlikely (free_cpuset))
|
||
free (default_attr.cpuset);
|
||
|
||
return retval;
|
||
}
|
||
versioned_symbol (libpthread, __pthread_create_2_1, pthread_create, GLIBC_2_1);
|
||
|
||
|
||
#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
|
||
int
|
||
__pthread_create_2_0 (newthread, attr, start_routine, arg)
|
||
pthread_t *newthread;
|
||
const pthread_attr_t *attr;
|
||
void *(*start_routine) (void *);
|
||
void *arg;
|
||
{
|
||
/* The ATTR attribute is not really of type `pthread_attr_t *'. It has
|
||
the old size and access to the new members might crash the program.
|
||
We convert the struct now. */
|
||
struct pthread_attr new_attr;
|
||
|
||
if (attr != NULL)
|
||
{
|
||
struct pthread_attr *iattr = (struct pthread_attr *) attr;
|
||
size_t ps = __getpagesize ();
|
||
|
||
/* Copy values from the user-provided attributes. */
|
||
new_attr.schedparam = iattr->schedparam;
|
||
new_attr.schedpolicy = iattr->schedpolicy;
|
||
new_attr.flags = iattr->flags;
|
||
|
||
/* Fill in default values for the fields not present in the old
|
||
implementation. */
|
||
new_attr.guardsize = ps;
|
||
new_attr.stackaddr = NULL;
|
||
new_attr.stacksize = 0;
|
||
new_attr.cpuset = NULL;
|
||
|
||
/* We will pass this value on to the real implementation. */
|
||
attr = (pthread_attr_t *) &new_attr;
|
||
}
|
||
|
||
return __pthread_create_2_1 (newthread, attr, start_routine, arg);
|
||
}
|
||
compat_symbol (libpthread, __pthread_create_2_0, pthread_create,
|
||
GLIBC_2_0);
|
||
#endif
|
||
|
||
/* Information for libthread_db. */
|
||
|
||
#include "../nptl_db/db_info.c"
|
||
|
||
/* If pthread_create is present, libgcc_eh.a and libsupc++.a expects some other POSIX thread
|
||
functions to be present as well. */
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_mutex_lock)
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_mutex_trylock)
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_mutex_unlock)
|
||
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_once)
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_cancel)
|
||
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_key_create)
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_key_delete)
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_setspecific)
|
||
PTHREAD_STATIC_FN_REQUIRE (pthread_getspecific)
|