[Glibc-bsd-commits] r4506 - trunk/glibc-ports/linuxthreads
Petr Salinger
ps-guest at alioth.debian.org
Thu May 30 17:42:37 UTC 2013
Author: ps-guest
Date: 2013-05-30 17:42:37 +0000 (Thu, 30 May 2013)
New Revision: 4506
Added:
trunk/glibc-ports/linuxthreads/manager.c
Log:
add manager.c (mising in r4429)
Added: trunk/glibc-ports/linuxthreads/manager.c
===================================================================
--- trunk/glibc-ports/linuxthreads/manager.c (rev 0)
+++ trunk/glibc-ports/linuxthreads/manager.c 2013-05-30 17:42:37 UTC (rev 4506)
@@ -0,0 +1,1124 @@
+/* Linuxthreads - a simple clone()-based implementation of Posix */
+/* threads for Linux. */
+/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy at 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;
+
+ /* Copy the stack guard canary. */
+#ifdef THREAD_COPY_STACK_GUARD
+ THREAD_COPY_STACK_GUARD (new_thread);
+#endif
+
+ /* Copy the pointer guard value. */
+#ifdef THREAD_COPY_POINTER_GUARD
+ THREAD_COPY_POINTER_GUARD (new_thread);
+#endif
+
+ /* 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 | CLONE_SYSVSEM |
+ __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 | CLONE_SYSVSEM |
+ __pthread_sig_cancel, new_thread);
+#else
+ pid = __clone(pthread_start_thread_event, stack_addr,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND | CLONE_SYSVSEM |
+ __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 | CLONE_SYSVSEM |
+ __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 | CLONE_SYSVSEM |
+ __pthread_sig_cancel, new_thread);
+#else
+ pid = __clone(pthread_start_thread, stack_addr,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND | CLONE_SYSVSEM |
+ __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;
+ guardaddr = th->p_stackaddr;
+# else
+ size_t stacksize = guardaddr - (char *)th;
+ guardaddr = (char *)th;
+# endif
+#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, ¶m);
+ manager_thread->p_priority = thread_prio;
+}
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