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-rw-r--r--linuxthreads/manager.c1112
1 files changed, 0 insertions, 1112 deletions
diff --git a/linuxthreads/manager.c b/linuxthreads/manager.c
deleted file mode 100644
index f21a6def6f..0000000000
--- a/linuxthreads/manager.c
+++ /dev/null
@@ -1,1112 +0,0 @@
-/* Linuxthreads - a simple clone()-based implementation of Posix */
-/* threads for Linux. */
-/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
-/* */
-/* This program is free software; you can redistribute it and/or */
-/* modify it under the terms of the GNU Library General Public License */
-/* as published by the Free Software Foundation; either version 2 */
-/* of the License, or (at your option) any later version. */
-/* */
-/* This program 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 Library General Public License for more details. */
-
-/* The "thread manager" thread: manages creation and termination of threads */
-
-#include <assert.h>
-#include <errno.h>
-#include <sched.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/poll.h> /* for poll */
-#include <sys/mman.h> /* for mmap */
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/wait.h> /* for waitpid macros */
-#include <locale.h> /* for __uselocale */
-#include <resolv.h> /* for __resp */
-
-#include <ldsodefs.h>
-#include "pthread.h"
-#include "internals.h"
-#include "spinlock.h"
-#include "restart.h"
-#include "semaphore.h"
-#include <not-cancel.h>
-
-/* For debugging purposes put the maximum number of threads in a variable. */
-const int __linuxthreads_pthread_threads_max = PTHREAD_THREADS_MAX;
-
-#ifndef THREAD_SELF
-/* Indicate whether at least one thread has a user-defined stack (if 1),
- or if all threads have stacks supplied by LinuxThreads (if 0). */
-int __pthread_nonstandard_stacks;
-#endif
-
-/* Number of active entries in __pthread_handles (used by gdb) */
-volatile int __pthread_handles_num = 2;
-
-/* Whether to use debugger additional actions for thread creation
- (set to 1 by gdb) */
-volatile int __pthread_threads_debug;
-
-/* Globally enabled events. */
-volatile td_thr_events_t __pthread_threads_events;
-
-/* Pointer to thread descriptor with last event. */
-volatile pthread_descr __pthread_last_event;
-
-static pthread_descr manager_thread;
-
-/* Mapping from stack segment to thread descriptor. */
-/* Stack segment numbers are also indices into the __pthread_handles array. */
-/* Stack segment number 0 is reserved for the initial thread. */
-
-#if FLOATING_STACKS
-# define thread_segment(seq) NULL
-#else
-static inline pthread_descr thread_segment(int seg)
-{
-# ifdef _STACK_GROWS_UP
- return (pthread_descr)(THREAD_STACK_START_ADDRESS + (seg - 1) * STACK_SIZE)
- + 1;
-# else
- return (pthread_descr)(THREAD_STACK_START_ADDRESS - (seg - 1) * STACK_SIZE)
- - 1;
-# endif
-}
-#endif
-
-/* Flag set in signal handler to record child termination */
-
-static volatile int terminated_children;
-
-/* Flag set when the initial thread is blocked on pthread_exit waiting
- for all other threads to terminate */
-
-static int main_thread_exiting;
-
-/* Counter used to generate unique thread identifier.
- Thread identifier is pthread_threads_counter + segment. */
-
-static pthread_t pthread_threads_counter;
-
-/* Forward declarations */
-
-static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
- void * (*start_routine)(void *), void *arg,
- sigset_t *mask, int father_pid,
- int report_events,
- td_thr_events_t *event_maskp);
-static void pthread_handle_free(pthread_t th_id);
-static void pthread_handle_exit(pthread_descr issuing_thread, int exitcode)
- __attribute__ ((noreturn));
-static void pthread_reap_children(void);
-static void pthread_kill_all_threads(int sig, int main_thread_also);
-static void pthread_for_each_thread(void *arg,
- void (*fn)(void *, pthread_descr));
-
-/* The server thread managing requests for thread creation and termination */
-
-int
-__attribute__ ((noreturn))
-__pthread_manager(void *arg)
-{
- pthread_descr self = manager_thread = arg;
- int reqfd = __pthread_manager_reader;
- struct pollfd ufd;
- sigset_t manager_mask;
- int n;
- struct pthread_request request;
-
- /* If we have special thread_self processing, initialize it. */
-#ifdef INIT_THREAD_SELF
- INIT_THREAD_SELF(self, 1);
-#endif
-#if !(USE_TLS && HAVE___THREAD)
- /* Set the error variable. */
- self->p_errnop = &self->p_errno;
- self->p_h_errnop = &self->p_h_errno;
-#endif
- /* Block all signals except __pthread_sig_cancel and SIGTRAP */
- sigfillset(&manager_mask);
- sigdelset(&manager_mask, __pthread_sig_cancel); /* for thread termination */
- sigdelset(&manager_mask, SIGTRAP); /* for debugging purposes */
- if (__pthread_threads_debug && __pthread_sig_debug > 0)
- sigdelset(&manager_mask, __pthread_sig_debug);
- sigprocmask(SIG_SETMASK, &manager_mask, NULL);
- /* Raise our priority to match that of main thread */
- __pthread_manager_adjust_prio(__pthread_main_thread->p_priority);
- /* Synchronize debugging of the thread manager */
- n = TEMP_FAILURE_RETRY(read_not_cancel(reqfd, (char *)&request,
- sizeof(request)));
- ASSERT(n == sizeof(request) && request.req_kind == REQ_DEBUG);
- ufd.fd = reqfd;
- ufd.events = POLLIN;
- /* Enter server loop */
- while(1) {
- n = __poll(&ufd, 1, 2000);
-
- /* Check for termination of the main thread */
- if (getppid() == 1) {
- pthread_kill_all_threads(SIGKILL, 0);
- _exit(0);
- }
- /* Check for dead children */
- if (terminated_children) {
- terminated_children = 0;
- pthread_reap_children();
- }
- /* Read and execute request */
- if (n == 1 && (ufd.revents & POLLIN)) {
- n = TEMP_FAILURE_RETRY(read_not_cancel(reqfd, (char *)&request,
- sizeof(request)));
-#ifdef DEBUG
- if (n < 0) {
- char d[64];
- write(STDERR_FILENO, d, snprintf(d, sizeof(d), "*** read err %m\n"));
- } else if (n != sizeof(request)) {
- write(STDERR_FILENO, "*** short read in manager\n", 26);
- }
-#endif
-
- switch(request.req_kind) {
- case REQ_CREATE:
- request.req_thread->p_retcode =
- pthread_handle_create((pthread_t *) &request.req_thread->p_retval,
- request.req_args.create.attr,
- request.req_args.create.fn,
- request.req_args.create.arg,
- &request.req_args.create.mask,
- request.req_thread->p_pid,
- request.req_thread->p_report_events,
- &request.req_thread->p_eventbuf.eventmask);
- restart(request.req_thread);
- break;
- case REQ_FREE:
- pthread_handle_free(request.req_args.free.thread_id);
- break;
- case REQ_PROCESS_EXIT:
- pthread_handle_exit(request.req_thread,
- request.req_args.exit.code);
- /* NOTREACHED */
- break;
- case REQ_MAIN_THREAD_EXIT:
- main_thread_exiting = 1;
- /* Reap children in case all other threads died and the signal handler
- went off before we set main_thread_exiting to 1, and therefore did
- not do REQ_KICK. */
- pthread_reap_children();
-
- if (__pthread_main_thread->p_nextlive == __pthread_main_thread) {
- restart(__pthread_main_thread);
- /* The main thread will now call exit() which will trigger an
- __on_exit handler, which in turn will send REQ_PROCESS_EXIT
- to the thread manager. In case you are wondering how the
- manager terminates from its loop here. */
- }
- break;
- case REQ_POST:
- __new_sem_post(request.req_args.post);
- break;
- case REQ_DEBUG:
- /* Make gdb aware of new thread and gdb will restart the
- new thread when it is ready to handle the new thread. */
- if (__pthread_threads_debug && __pthread_sig_debug > 0)
- raise(__pthread_sig_debug);
- break;
- case REQ_KICK:
- /* This is just a prod to get the manager to reap some
- threads right away, avoiding a potential delay at shutdown. */
- break;
- case REQ_FOR_EACH_THREAD:
- pthread_for_each_thread(request.req_args.for_each.arg,
- request.req_args.for_each.fn);
- restart(request.req_thread);
- break;
- }
- }
- }
-}
-
-int __pthread_manager_event(void *arg)
-{
- pthread_descr self = arg;
- /* If we have special thread_self processing, initialize it. */
-#ifdef INIT_THREAD_SELF
- INIT_THREAD_SELF(self, 1);
-#endif
-
- /* Get the lock the manager will free once all is correctly set up. */
- __pthread_lock (THREAD_GETMEM(self, p_lock), NULL);
- /* Free it immediately. */
- __pthread_unlock (THREAD_GETMEM(self, p_lock));
-
- return __pthread_manager(arg);
-}
-
-/* Process creation */
-
-static int
-__attribute__ ((noreturn))
-pthread_start_thread(void *arg)
-{
- pthread_descr self = (pthread_descr) arg;
- struct pthread_request request;
- void * outcome;
-#if HP_TIMING_AVAIL
- hp_timing_t tmpclock;
-#endif
- /* Initialize special thread_self processing, if any. */
-#ifdef INIT_THREAD_SELF
- INIT_THREAD_SELF(self, self->p_nr);
-#endif
-#if HP_TIMING_AVAIL
- HP_TIMING_NOW (tmpclock);
- THREAD_SETMEM (self, p_cpuclock_offset, tmpclock);
-#endif
- /* Make sure our pid field is initialized, just in case we get there
- before our father has initialized it. */
- THREAD_SETMEM(self, p_pid, __getpid());
- /* Initial signal mask is that of the creating thread. (Otherwise,
- we'd just inherit the mask of the thread manager.) */
- sigprocmask(SIG_SETMASK, &self->p_start_args.mask, NULL);
- /* Set the scheduling policy and priority for the new thread, if needed */
- if (THREAD_GETMEM(self, p_start_args.schedpolicy) >= 0)
- /* Explicit scheduling attributes were provided: apply them */
- __sched_setscheduler(THREAD_GETMEM(self, p_pid),
- THREAD_GETMEM(self, p_start_args.schedpolicy),
- &self->p_start_args.schedparam);
- else if (manager_thread->p_priority > 0)
- /* Default scheduling required, but thread manager runs in realtime
- scheduling: switch new thread to SCHED_OTHER policy */
- {
- struct sched_param default_params;
- default_params.sched_priority = 0;
- __sched_setscheduler(THREAD_GETMEM(self, p_pid),
- SCHED_OTHER, &default_params);
- }
-#if !(USE_TLS && HAVE___THREAD)
- /* Initialize thread-locale current locale to point to the global one.
- With __thread support, the variable's initializer takes care of this. */
- __uselocale (LC_GLOBAL_LOCALE);
-#else
- /* Initialize __resp. */
- __resp = &self->p_res;
-#endif
- /* Make gdb aware of new thread */
- if (__pthread_threads_debug && __pthread_sig_debug > 0) {
- request.req_thread = self;
- request.req_kind = REQ_DEBUG;
- TEMP_FAILURE_RETRY(write_not_cancel(__pthread_manager_request,
- (char *) &request, sizeof(request)));
- suspend(self);
- }
- /* Run the thread code */
- outcome = self->p_start_args.start_routine(THREAD_GETMEM(self,
- p_start_args.arg));
- /* Exit with the given return value */
- __pthread_do_exit(outcome, CURRENT_STACK_FRAME);
-}
-
-static int
-__attribute__ ((noreturn))
-pthread_start_thread_event(void *arg)
-{
- pthread_descr self = (pthread_descr) arg;
-
-#ifdef INIT_THREAD_SELF
- INIT_THREAD_SELF(self, self->p_nr);
-#endif
- /* Make sure our pid field is initialized, just in case we get there
- before our father has initialized it. */
- THREAD_SETMEM(self, p_pid, __getpid());
- /* Get the lock the manager will free once all is correctly set up. */
- __pthread_lock (THREAD_GETMEM(self, p_lock), NULL);
- /* Free it immediately. */
- __pthread_unlock (THREAD_GETMEM(self, p_lock));
-
- /* Continue with the real function. */
- pthread_start_thread (arg);
-}
-
-#if defined USE_TLS && !FLOATING_STACKS
-# error "TLS can only work with floating stacks"
-#endif
-
-static int pthread_allocate_stack(const pthread_attr_t *attr,
- pthread_descr default_new_thread,
- int pagesize,
- char ** out_new_thread,
- char ** out_new_thread_bottom,
- char ** out_guardaddr,
- size_t * out_guardsize,
- size_t * out_stacksize)
-{
- pthread_descr new_thread;
- char * new_thread_bottom;
- char * guardaddr;
- size_t stacksize, guardsize;
-
-#ifdef USE_TLS
- /* TLS cannot work with fixed thread descriptor addresses. */
- assert (default_new_thread == NULL);
-#endif
-
- if (attr != NULL && attr->__stackaddr_set)
- {
-#ifdef _STACK_GROWS_UP
- /* The user provided a stack. */
-# ifdef USE_TLS
- /* This value is not needed. */
- new_thread = (pthread_descr) attr->__stackaddr;
- new_thread_bottom = (char *) new_thread;
-# else
- new_thread = (pthread_descr) attr->__stackaddr;
- new_thread_bottom = (char *) (new_thread + 1);
-# endif
- guardaddr = attr->__stackaddr + attr->__stacksize;
- guardsize = 0;
-#else
- /* The user provided a stack. For now we interpret the supplied
- address as 1 + the highest addr. in the stack segment. If a
- separate register stack is needed, we place it at the low end
- of the segment, relying on the associated stacksize to
- determine the low end of the segment. This differs from many
- (but not all) other pthreads implementations. The intent is
- that on machines with a single stack growing toward higher
- addresses, stackaddr would be the lowest address in the stack
- segment, so that it is consistently close to the initial sp
- value. */
-# ifdef USE_TLS
- new_thread = (pthread_descr) attr->__stackaddr;
-# else
- new_thread =
- (pthread_descr) ((long)(attr->__stackaddr) & -sizeof(void *)) - 1;
-# endif
- new_thread_bottom = (char *) attr->__stackaddr - attr->__stacksize;
- guardaddr = new_thread_bottom;
- guardsize = 0;
-#endif
-#ifndef THREAD_SELF
- __pthread_nonstandard_stacks = 1;
-#endif
-#ifndef USE_TLS
- /* Clear the thread data structure. */
- memset (new_thread, '\0', sizeof (*new_thread));
-#endif
- stacksize = attr->__stacksize;
- }
- else
- {
-#ifdef NEED_SEPARATE_REGISTER_STACK
- const size_t granularity = 2 * pagesize;
- /* Try to make stacksize/2 a multiple of pagesize */
-#else
- const size_t granularity = pagesize;
-#endif
- void *map_addr;
-
- /* Allocate space for stack and thread descriptor at default address */
-#if FLOATING_STACKS
- if (attr != NULL)
- {
- guardsize = page_roundup (attr->__guardsize, granularity);
- stacksize = __pthread_max_stacksize - guardsize;
- stacksize = MIN (stacksize,
- page_roundup (attr->__stacksize, granularity));
- }
- else
- {
- guardsize = granularity;
- stacksize = __pthread_max_stacksize - guardsize;
- }
-
- map_addr = mmap(NULL, stacksize + guardsize,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (map_addr == MAP_FAILED)
- /* No more memory available. */
- return -1;
-
-# ifdef NEED_SEPARATE_REGISTER_STACK
- guardaddr = map_addr + stacksize / 2;
- if (guardsize > 0)
- mprotect (guardaddr, guardsize, PROT_NONE);
-
- new_thread_bottom = (char *) map_addr;
-# ifdef USE_TLS
- new_thread = ((pthread_descr) (new_thread_bottom + stacksize
- + guardsize));
-# else
- new_thread = ((pthread_descr) (new_thread_bottom + stacksize
- + guardsize)) - 1;
-# endif
-# elif _STACK_GROWS_DOWN
- guardaddr = map_addr;
- if (guardsize > 0)
- mprotect (guardaddr, guardsize, PROT_NONE);
-
- new_thread_bottom = (char *) map_addr + guardsize;
-# ifdef USE_TLS
- new_thread = ((pthread_descr) (new_thread_bottom + stacksize));
-# else
- new_thread = ((pthread_descr) (new_thread_bottom + stacksize)) - 1;
-# endif
-# elif _STACK_GROWS_UP
- guardaddr = map_addr + stacksize;
- if (guardsize > 0)
- mprotect (guardaddr, guardsize, PROT_NONE);
-
- new_thread = (pthread_descr) map_addr;
-# ifdef USE_TLS
- new_thread_bottom = (char *) new_thread;
-# else
- new_thread_bottom = (char *) (new_thread + 1);
-# endif
-# else
-# error You must define a stack direction
-# endif /* Stack direction */
-#else /* !FLOATING_STACKS */
- void *res_addr;
-
- if (attr != NULL)
- {
- guardsize = page_roundup (attr->__guardsize, granularity);
- stacksize = STACK_SIZE - guardsize;
- stacksize = MIN (stacksize,
- page_roundup (attr->__stacksize, granularity));
- }
- else
- {
- guardsize = granularity;
- stacksize = STACK_SIZE - granularity;
- }
-
-# ifdef NEED_SEPARATE_REGISTER_STACK
- new_thread = default_new_thread;
- new_thread_bottom = (char *) (new_thread + 1) - stacksize - guardsize;
- /* Includes guard area, unlike the normal case. Use the bottom
- end of the segment as backing store for the register stack.
- Needed on IA64. In this case, we also map the entire stack at
- once. According to David Mosberger, that's cheaper. It also
- avoids the risk of intermittent failures due to other mappings
- in the same region. The cost is that we might be able to map
- slightly fewer stacks. */
-
- /* First the main stack: */
- map_addr = (caddr_t)((char *)(new_thread + 1) - stacksize / 2);
- res_addr = mmap(map_addr, stacksize / 2,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (res_addr != map_addr)
- {
- /* Bad luck, this segment is already mapped. */
- if (res_addr != MAP_FAILED)
- munmap(res_addr, stacksize / 2);
- return -1;
- }
- /* Then the register stack: */
- map_addr = (caddr_t)new_thread_bottom;
- res_addr = mmap(map_addr, stacksize/2,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (res_addr != map_addr)
- {
- if (res_addr != MAP_FAILED)
- munmap(res_addr, stacksize / 2);
- munmap((caddr_t)((char *)(new_thread + 1) - stacksize/2),
- stacksize/2);
- return -1;
- }
-
- guardaddr = new_thread_bottom + stacksize/2;
- /* We leave the guard area in the middle unmapped. */
-# else /* !NEED_SEPARATE_REGISTER_STACK */
-# ifdef _STACK_GROWS_DOWN
- new_thread = default_new_thread;
- new_thread_bottom = (char *) (new_thread + 1) - stacksize;
- map_addr = new_thread_bottom - guardsize;
- res_addr = mmap(map_addr, stacksize + guardsize,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (res_addr != map_addr)
- {
- /* Bad luck, this segment is already mapped. */
- if (res_addr != MAP_FAILED)
- munmap (res_addr, stacksize + guardsize);
- return -1;
- }
-
- /* We manage to get a stack. Protect the guard area pages if
- necessary. */
- guardaddr = map_addr;
- if (guardsize > 0)
- mprotect (guardaddr, guardsize, PROT_NONE);
-# else
- /* The thread description goes at the bottom of this area, and
- * the stack starts directly above it.
- */
- new_thread = (pthread_descr)((unsigned long)default_new_thread &~ (STACK_SIZE - 1));
- map_addr = mmap(new_thread, stacksize + guardsize,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (map_addr == MAP_FAILED)
- return -1;
-
- new_thread_bottom = map_addr + sizeof(*new_thread);
- guardaddr = map_addr + stacksize;
- if (guardsize > 0)
- mprotect (guardaddr, guardsize, PROT_NONE);
-
-# endif /* stack direction */
-# endif /* !NEED_SEPARATE_REGISTER_STACK */
-#endif /* !FLOATING_STACKS */
- }
- *out_new_thread = (char *) new_thread;
- *out_new_thread_bottom = new_thread_bottom;
- *out_guardaddr = guardaddr;
- *out_guardsize = guardsize;
-#ifdef NEED_SEPARATE_REGISTER_STACK
- *out_stacksize = stacksize / 2;
-#else
- *out_stacksize = stacksize;
-#endif
- return 0;
-}
-
-static int pthread_handle_create(pthread_t *thread, const pthread_attr_t *attr,
- void * (*start_routine)(void *), void *arg,
- sigset_t * mask, int father_pid,
- int report_events,
- td_thr_events_t *event_maskp)
-{
- size_t sseg;
- int pid;
- pthread_descr new_thread;
- char *stack_addr;
- char * new_thread_bottom;
- pthread_t new_thread_id;
- char *guardaddr = NULL;
- size_t guardsize = 0, stksize = 0;
- int pagesize = __getpagesize();
- int saved_errno = 0;
-
-#ifdef USE_TLS
- new_thread = _dl_allocate_tls (NULL);
- if (new_thread == NULL)
- return EAGAIN;
-# if TLS_DTV_AT_TP
- /* pthread_descr is below TP. */
- new_thread = (pthread_descr) ((char *) new_thread - TLS_PRE_TCB_SIZE);
-# endif
-#else
- /* Prevent warnings. */
- new_thread = NULL;
-#endif
-
- /* First check whether we have to change the policy and if yes, whether
- we can do this. Normally this should be done by examining the
- return value of the __sched_setscheduler call in pthread_start_thread
- but this is hard to implement. FIXME */
- if (attr != NULL && attr->__schedpolicy != SCHED_OTHER && geteuid () != 0)
- return EPERM;
- /* Find a free segment for the thread, and allocate a stack if needed */
- for (sseg = 2; ; sseg++)
- {
- if (sseg >= PTHREAD_THREADS_MAX)
- {
-#ifdef USE_TLS
-# if TLS_DTV_AT_TP
- new_thread = (pthread_descr) ((char *) new_thread + TLS_PRE_TCB_SIZE);
-# endif
- _dl_deallocate_tls (new_thread, true);
-#endif
- return EAGAIN;
- }
- if (__pthread_handles[sseg].h_descr != NULL)
- continue;
- if (pthread_allocate_stack(attr, thread_segment(sseg),
- pagesize, &stack_addr, &new_thread_bottom,
- &guardaddr, &guardsize, &stksize) == 0)
- {
-#ifdef USE_TLS
- new_thread->p_stackaddr = stack_addr;
-#else
- new_thread = (pthread_descr) stack_addr;
-#endif
- break;
- }
- }
- __pthread_handles_num++;
- /* Allocate new thread identifier */
- pthread_threads_counter += PTHREAD_THREADS_MAX;
- new_thread_id = sseg + pthread_threads_counter;
- /* Initialize the thread descriptor. Elements which have to be
- initialized to zero already have this value. */
-#if !defined USE_TLS || !TLS_DTV_AT_TP
- new_thread->p_header.data.tcb = new_thread;
- new_thread->p_header.data.self = new_thread;
-#endif
-#if TLS_MULTIPLE_THREADS_IN_TCB || !defined USE_TLS || !TLS_DTV_AT_TP
- new_thread->p_multiple_threads = 1;
-#endif
- new_thread->p_tid = new_thread_id;
- new_thread->p_lock = &(__pthread_handles[sseg].h_lock);
- new_thread->p_cancelstate = PTHREAD_CANCEL_ENABLE;
- new_thread->p_canceltype = PTHREAD_CANCEL_DEFERRED;
-#if !(USE_TLS && HAVE___THREAD)
- new_thread->p_errnop = &new_thread->p_errno;
- new_thread->p_h_errnop = &new_thread->p_h_errno;
- new_thread->p_resp = &new_thread->p_res;
-#endif
- new_thread->p_guardaddr = guardaddr;
- new_thread->p_guardsize = guardsize;
- new_thread->p_nr = sseg;
- new_thread->p_inheritsched = attr ? attr->__inheritsched : 0;
- new_thread->p_alloca_cutoff = stksize / 4 > __MAX_ALLOCA_CUTOFF
- ? __MAX_ALLOCA_CUTOFF : stksize / 4;
- /* Initialize the thread handle */
- __pthread_init_lock(&__pthread_handles[sseg].h_lock);
- __pthread_handles[sseg].h_descr = new_thread;
- __pthread_handles[sseg].h_bottom = new_thread_bottom;
- /* Determine scheduling parameters for the thread */
- new_thread->p_start_args.schedpolicy = -1;
- if (attr != NULL) {
- new_thread->p_detached = attr->__detachstate;
- new_thread->p_userstack = attr->__stackaddr_set;
-
- switch(attr->__inheritsched) {
- case PTHREAD_EXPLICIT_SCHED:
- new_thread->p_start_args.schedpolicy = attr->__schedpolicy;
- memcpy (&new_thread->p_start_args.schedparam, &attr->__schedparam,
- sizeof (struct sched_param));
- break;
- case PTHREAD_INHERIT_SCHED:
- new_thread->p_start_args.schedpolicy = __sched_getscheduler(father_pid);
- __sched_getparam(father_pid, &new_thread->p_start_args.schedparam);
- break;
- }
- new_thread->p_priority =
- new_thread->p_start_args.schedparam.sched_priority;
- }
- /* Finish setting up arguments to pthread_start_thread */
- new_thread->p_start_args.start_routine = start_routine;
- new_thread->p_start_args.arg = arg;
- new_thread->p_start_args.mask = *mask;
- /* Make the new thread ID available already now. If any of the later
- functions fail we return an error value and the caller must not use
- the stored thread ID. */
- *thread = new_thread_id;
- /* Raise priority of thread manager if needed */
- __pthread_manager_adjust_prio(new_thread->p_priority);
- /* Do the cloning. We have to use two different functions depending
- on whether we are debugging or not. */
- pid = 0; /* Note that the thread never can have PID zero. */
- if (report_events)
- {
- /* See whether the TD_CREATE event bit is set in any of the
- masks. */
- int idx = __td_eventword (TD_CREATE);
- uint32_t mask = __td_eventmask (TD_CREATE);
-
- if ((mask & (__pthread_threads_events.event_bits[idx]
- | event_maskp->event_bits[idx])) != 0)
- {
- /* Lock the mutex the child will use now so that it will stop. */
- __pthread_lock(new_thread->p_lock, NULL);
-
- /* We have to report this event. */
-#ifdef NEED_SEPARATE_REGISTER_STACK
- /* Perhaps this version should be used on all platforms. But
- this requires that __clone2 be uniformly supported
- everywhere.
-
- And there is some argument for changing the __clone2
- interface to pass sp and bsp instead, making it more IA64
- specific, but allowing stacks to grow outward from each
- other, to get less paging and fewer mmaps. */
- pid = __clone2(pthread_start_thread_event,
- (void **)new_thread_bottom,
- (char *)stack_addr - new_thread_bottom,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
- __pthread_sig_cancel, new_thread);
-#elif _STACK_GROWS_UP
- pid = __clone(pthread_start_thread_event, (void *) new_thread_bottom,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
- __pthread_sig_cancel, new_thread);
-#else
- pid = __clone(pthread_start_thread_event, stack_addr,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
- __pthread_sig_cancel, new_thread);
-#endif
- saved_errno = errno;
- if (pid != -1)
- {
- /* 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. */
- new_thread->p_eventbuf.eventdata = new_thread;
- new_thread->p_eventbuf.eventnum = TD_CREATE;
- __pthread_last_event = new_thread;
-
- /* We have to set the PID here since the callback function
- in the debug library will need it and we cannot guarantee
- the child got scheduled before the debugger. */
- new_thread->p_pid = pid;
-
- /* Now call the function which signals the event. */
- __linuxthreads_create_event ();
-
- /* Now restart the thread. */
- __pthread_unlock(new_thread->p_lock);
- }
- }
- }
- if (pid == 0)
- {
-#ifdef NEED_SEPARATE_REGISTER_STACK
- pid = __clone2(pthread_start_thread,
- (void **)new_thread_bottom,
- (char *)stack_addr - new_thread_bottom,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
- __pthread_sig_cancel, new_thread);
-#elif _STACK_GROWS_UP
- pid = __clone(pthread_start_thread, (void *) new_thread_bottom,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
- __pthread_sig_cancel, new_thread);
-#else
- pid = __clone(pthread_start_thread, stack_addr,
- CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
- __pthread_sig_cancel, new_thread);
-#endif /* !NEED_SEPARATE_REGISTER_STACK */
- saved_errno = errno;
- }
- /* Check if cloning succeeded */
- if (pid == -1) {
- /* Free the stack if we allocated it */
- if (attr == NULL || !attr->__stackaddr_set)
- {
-#ifdef NEED_SEPARATE_REGISTER_STACK
- size_t stacksize = ((char *)(new_thread->p_guardaddr)
- - new_thread_bottom);
- munmap((caddr_t)new_thread_bottom,
- 2 * stacksize + new_thread->p_guardsize);
-#elif _STACK_GROWS_UP
-# ifdef USE_TLS
- size_t stacksize = guardaddr - stack_addr;
- munmap(stack_addr, stacksize + guardsize);
-# else
- size_t stacksize = guardaddr - (char *)new_thread;
- munmap(new_thread, stacksize + guardsize);
-# endif
-#else
-# ifdef USE_TLS
- size_t stacksize = stack_addr - new_thread_bottom;
-# else
- size_t stacksize = (char *)(new_thread+1) - new_thread_bottom;
-# endif
- munmap(new_thread_bottom - guardsize, guardsize + stacksize);
-#endif
- }
-#ifdef USE_TLS
-# if TLS_DTV_AT_TP
- new_thread = (pthread_descr) ((char *) new_thread + TLS_PRE_TCB_SIZE);
-# endif
- _dl_deallocate_tls (new_thread, true);
-#endif
- __pthread_handles[sseg].h_descr = NULL;
- __pthread_handles[sseg].h_bottom = NULL;
- __pthread_handles_num--;
- return saved_errno;
- }
- /* Insert new thread in doubly linked list of active threads */
- new_thread->p_prevlive = __pthread_main_thread;
- new_thread->p_nextlive = __pthread_main_thread->p_nextlive;
- __pthread_main_thread->p_nextlive->p_prevlive = new_thread;
- __pthread_main_thread->p_nextlive = new_thread;
- /* Set pid field of the new thread, in case we get there before the
- child starts. */
- new_thread->p_pid = pid;
- return 0;
-}
-
-
-/* Try to free the resources of a thread when requested by pthread_join
- or pthread_detach on a terminated thread. */
-
-static void pthread_free(pthread_descr th)
-{
- pthread_handle handle;
- pthread_readlock_info *iter, *next;
-
- ASSERT(th->p_exited);
- /* Make the handle invalid */
- handle = thread_handle(th->p_tid);
- __pthread_lock(&handle->h_lock, NULL);
- handle->h_descr = NULL;
- handle->h_bottom = (char *)(-1L);
- __pthread_unlock(&handle->h_lock);
-#ifdef FREE_THREAD
- FREE_THREAD(th, th->p_nr);
-#endif
- /* One fewer threads in __pthread_handles */
- __pthread_handles_num--;
-
- /* Destroy read lock list, and list of free read lock structures.
- If the former is not empty, it means the thread exited while
- holding read locks! */
-
- for (iter = th->p_readlock_list; iter != NULL; iter = next)
- {
- next = iter->pr_next;
- free(iter);
- }
-
- for (iter = th->p_readlock_free; iter != NULL; iter = next)
- {
- next = iter->pr_next;
- free(iter);
- }
-
- /* If initial thread, nothing to free */
- if (!th->p_userstack)
- {
- size_t guardsize = th->p_guardsize;
- /* Free the stack and thread descriptor area */
- char *guardaddr = th->p_guardaddr;
-#ifdef _STACK_GROWS_UP
-# ifdef USE_TLS
- size_t stacksize = guardaddr - th->p_stackaddr;
-# else
- size_t stacksize = guardaddr - (char *)th;
-# endif
- guardaddr = (char *)th;
-#else
- /* Guardaddr is always set, even if guardsize is 0. This allows
- us to compute everything else. */
-# ifdef USE_TLS
- size_t stacksize = th->p_stackaddr - guardaddr - guardsize;
-# else
- size_t stacksize = (char *)(th+1) - guardaddr - guardsize;
-# endif
-# ifdef NEED_SEPARATE_REGISTER_STACK
- /* Take account of the register stack, which is below guardaddr. */
- guardaddr -= stacksize;
- stacksize *= 2;
-# endif
-#endif
- /* Unmap the stack. */
- munmap(guardaddr, stacksize + guardsize);
-
- }
-
-#ifdef USE_TLS
-# if TLS_DTV_AT_TP
- th = (pthread_descr) ((char *) th + TLS_PRE_TCB_SIZE);
-# endif
- _dl_deallocate_tls (th, true);
-#endif
-}
-
-/* Handle threads that have exited */
-
-static void pthread_exited(pid_t pid)
-{
- pthread_descr th;
- int detached;
- /* Find thread with that pid */
- for (th = __pthread_main_thread->p_nextlive;
- th != __pthread_main_thread;
- th = th->p_nextlive) {
- if (th->p_pid == pid) {
- /* Remove thread from list of active threads */
- th->p_nextlive->p_prevlive = th->p_prevlive;
- th->p_prevlive->p_nextlive = th->p_nextlive;
- /* Mark thread as exited, and if detached, free its resources */
- __pthread_lock(th->p_lock, NULL);
- th->p_exited = 1;
- /* If we have to signal this event do it now. */
- if (th->p_report_events)
- {
- /* See whether TD_REAP is in any of the mask. */
- int idx = __td_eventword (TD_REAP);
- uint32_t mask = __td_eventmask (TD_REAP);
-
- if ((mask & (__pthread_threads_events.event_bits[idx]
- | th->p_eventbuf.eventmask.event_bits[idx])) != 0)
- {
- /* Yep, we have to signal the reapage. */
- th->p_eventbuf.eventnum = TD_REAP;
- th->p_eventbuf.eventdata = th;
- __pthread_last_event = th;
-
- /* Now call the function to signal the event. */
- __linuxthreads_reap_event();
- }
- }
- detached = th->p_detached;
- __pthread_unlock(th->p_lock);
- if (detached)
- pthread_free(th);
- break;
- }
- }
- /* If all threads have exited and the main thread is pending on a
- pthread_exit, wake up the main thread and terminate ourselves. */
- if (main_thread_exiting &&
- __pthread_main_thread->p_nextlive == __pthread_main_thread) {
- restart(__pthread_main_thread);
- /* Same logic as REQ_MAIN_THREAD_EXIT. */
- }
-}
-
-static void pthread_reap_children(void)
-{
- pid_t pid;
- int status;
-
- while ((pid = waitpid_not_cancel(-1, &status, WNOHANG | __WCLONE)) > 0) {
- pthread_exited(pid);
- if (WIFSIGNALED(status)) {
- /* If a thread died due to a signal, send the same signal to
- all other threads, including the main thread. */
- pthread_kill_all_threads(WTERMSIG(status), 1);
- _exit(0);
- }
- }
-}
-
-/* Try to free the resources of a thread when requested by pthread_join
- or pthread_detach on a terminated thread. */
-
-static void pthread_handle_free(pthread_t th_id)
-{
- pthread_handle handle = thread_handle(th_id);
- pthread_descr th;
-
- __pthread_lock(&handle->h_lock, NULL);
- if (nonexisting_handle(handle, th_id)) {
- /* pthread_reap_children has deallocated the thread already,
- nothing needs to be done */
- __pthread_unlock(&handle->h_lock);
- return;
- }
- th = handle->h_descr;
- if (th->p_exited) {
- __pthread_unlock(&handle->h_lock);
- pthread_free(th);
- } else {
- /* The Unix process of the thread is still running.
- Mark the thread as detached so that the thread manager will
- deallocate its resources when the Unix process exits. */
- th->p_detached = 1;
- __pthread_unlock(&handle->h_lock);
- }
-}
-
-/* Send a signal to all running threads */
-
-static void pthread_kill_all_threads(int sig, int main_thread_also)
-{
- pthread_descr th;
- for (th = __pthread_main_thread->p_nextlive;
- th != __pthread_main_thread;
- th = th->p_nextlive) {
- kill(th->p_pid, sig);
- }
- if (main_thread_also) {
- kill(__pthread_main_thread->p_pid, sig);
- }
-}
-
-static void pthread_for_each_thread(void *arg,
- void (*fn)(void *, pthread_descr))
-{
- pthread_descr th;
-
- for (th = __pthread_main_thread->p_nextlive;
- th != __pthread_main_thread;
- th = th->p_nextlive) {
- fn(arg, th);
- }
-
- fn(arg, __pthread_main_thread);
-}
-
-/* Process-wide exit() */
-
-static void pthread_handle_exit(pthread_descr issuing_thread, int exitcode)
-{
- pthread_descr th;
- __pthread_exit_requested = 1;
- __pthread_exit_code = exitcode;
- /* A forced asynchronous cancellation follows. Make sure we won't
- get stuck later in the main thread with a system lock being held
- by one of the cancelled threads. Ideally one would use the same
- code as in pthread_atfork(), but we can't distinguish system and
- user handlers there. */
- __flockfilelist();
- /* Send the CANCEL signal to all running threads, including the main
- thread, but excluding the thread from which the exit request originated
- (that thread must complete the exit, e.g. calling atexit functions
- and flushing stdio buffers). */
- for (th = issuing_thread->p_nextlive;
- th != issuing_thread;
- th = th->p_nextlive) {
- kill(th->p_pid, __pthread_sig_cancel);
- }
- /* Now, wait for all these threads, so that they don't become zombies
- and their times are properly added to the thread manager's times. */
- for (th = issuing_thread->p_nextlive;
- th != issuing_thread;
- th = th->p_nextlive) {
- waitpid(th->p_pid, NULL, __WCLONE);
- }
- __fresetlockfiles();
- restart(issuing_thread);
- _exit(0);
-}
-
-/* Handler for __pthread_sig_cancel in thread manager thread */
-
-void __pthread_manager_sighandler(int sig)
-{
- int kick_manager = terminated_children == 0 && main_thread_exiting;
- terminated_children = 1;
-
- /* If the main thread is terminating, kick the thread manager loop
- each time some threads terminate. This eliminates a two second
- shutdown delay caused by the thread manager sleeping in the
- call to __poll(). Instead, the thread manager is kicked into
- action, reaps the outstanding threads and resumes the main thread
- so that it can complete the shutdown. */
-
- if (kick_manager) {
- struct pthread_request request;
- request.req_thread = 0;
- request.req_kind = REQ_KICK;
- TEMP_FAILURE_RETRY(write_not_cancel(__pthread_manager_request,
- (char *) &request, sizeof(request)));
- }
-}
-
-/* Adjust priority of thread manager so that it always run at a priority
- higher than all threads */
-
-void __pthread_manager_adjust_prio(int thread_prio)
-{
- struct sched_param param;
-
- if (thread_prio <= manager_thread->p_priority) return;
- param.sched_priority =
- thread_prio < __sched_get_priority_max(SCHED_FIFO)
- ? thread_prio + 1 : thread_prio;
- __sched_setscheduler(manager_thread->p_pid, SCHED_FIFO, &param);
- manager_thread->p_priority = thread_prio;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-05 17:36:04 +0000