summaryrefslogtreecommitdiff
path: root/libpthread/linuxthreads.old/manager.c
diff options
context:
space:
mode:
authorMike Frysinger <vapier@gentoo.org>2005-11-15 03:13:04 +0000
committerMike Frysinger <vapier@gentoo.org>2005-11-15 03:13:04 +0000
commita9f5aa1cc96fc2c71f19a9c3e9dcbee0e78f83ca (patch)
tree2c5d251bdfd06d0a76cec9fc507b1873b4bbbdad /libpthread/linuxthreads.old/manager.c
parentfd6dde5a19092be5bb1990dadd5c595d2ed0b3aa (diff)
rename current stable linuxthreads to linuxthreads.old to prepare for import of latest glibc version
Diffstat (limited to 'libpthread/linuxthreads.old/manager.c')
-rw-r--r--libpthread/linuxthreads.old/manager.c905
1 files changed, 905 insertions, 0 deletions
diff --git a/libpthread/linuxthreads.old/manager.c b/libpthread/linuxthreads.old/manager.c
new file mode 100644
index 000000000..204344aef
--- /dev/null
+++ b/libpthread/linuxthreads.old/manager.c
@@ -0,0 +1,905 @@
+/* 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 */
+
+/* mods for uClibc: getpwd and getpagesize are the syscalls */
+#define __getpid getpid
+#define __getpagesize getpagesize
+
+#include <features.h>
+#define __USE_GNU
+#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 "pthread.h"
+#include "internals.h"
+#include "spinlock.h"
+#include "restart.h"
+#include "semaphore.h"
+#include "debug.h" /* PDEBUG, added by StS */
+
+
+/* poll() is not supported in kernel <= 2.0, therefore is __NR_poll is
+ * not available, we assume an old Linux kernel is in use and we will
+ * use select() instead. */
+#include <sys/syscall.h>
+#ifndef __NR_poll
+# define USE_SELECT
+#endif
+
+
+/* Array of active threads. Entry 0 is reserved for the initial thread. */
+struct pthread_handle_struct __pthread_handles[PTHREAD_THREADS_MAX] =
+{ { __LOCK_INITIALIZER, &__pthread_initial_thread, 0},
+ { __LOCK_INITIALIZER, &__pthread_manager_thread, 0}, /* All NULLs */ };
+
+/* For debugging purposes put the maximum number of threads in a variable. */
+const int __linuxthreads_pthread_threads_max = PTHREAD_THREADS_MAX;
+
+/* 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;
+
+/* 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;
+
+/* 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. */
+
+static inline pthread_descr thread_segment(int seg)
+{
+ return (pthread_descr)(THREAD_STACK_START_ADDRESS - (seg - 1) * STACK_SIZE)
+ - 1;
+}
+
+/* Flag set in signal handler to record child termination */
+
+static volatile int terminated_children = 0;
+
+/* Flag set when the initial thread is blocked on pthread_exit waiting
+ for all other threads to terminate */
+
+static int main_thread_exiting = 0;
+
+/* Counter used to generate unique thread identifier.
+ Thread identifier is pthread_threads_counter + segment. */
+
+static pthread_t pthread_threads_counter = 0;
+
+/* 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);
+static void pthread_reap_children(void);
+static void pthread_kill_all_threads(int sig, int main_thread_also);
+
+/* The server thread managing requests for thread creation and termination */
+
+int __pthread_manager(void *arg)
+{
+ int reqfd = (int) (long int) arg;
+#ifdef USE_SELECT
+ struct timeval tv;
+ fd_set fd;
+#else
+ struct pollfd ufd;
+#endif
+ 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(&__pthread_manager_thread, 1);
+#endif
+ /* Set the error variable. */
+ __pthread_manager_thread.p_errnop = &__pthread_manager_thread.p_errno;
+ __pthread_manager_thread.p_h_errnop = &__pthread_manager_thread.p_h_errno;
+
+#ifdef __UCLIBC_HAS_XLOCALE__
+ /* Initialize thread's locale to the global locale. */
+ __pthread_manager_thread.locale = __global_locale;
+#endif /* __UCLIBC_HAS_XLOCALE__ */
+
+ /* 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(__libc_read(reqfd, (char *)&request,
+ sizeof(request)));
+ ASSERT(n == sizeof(request) && request.req_kind == REQ_DEBUG);
+#ifndef USE_SELECT
+ ufd.fd = reqfd;
+ ufd.events = POLLIN;
+#endif
+ /* Enter server loop */
+ while(1) {
+#ifdef USE_SELECT
+ tv.tv_sec = 2;
+ tv.tv_usec = 0;
+ FD_ZERO (&fd);
+ FD_SET (reqfd, &fd);
+ n = select (reqfd + 1, &fd, NULL, NULL, &tv);
+#else
+ PDEBUG("before poll\n");
+ n = poll(&ufd, 1, 2000);
+ PDEBUG("after poll\n");
+#endif
+ /* 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 */
+#ifdef USE_SELECT
+ if (n == 1)
+#else
+ if (n == 1 && (ufd.revents & POLLIN))
+#endif
+ {
+
+ PDEBUG("before __libc_read\n");
+ n = __libc_read(reqfd, (char *)&request, sizeof(request));
+ PDEBUG("after __libc_read, n=%d\n", n);
+ ASSERT(n == sizeof(request));
+ switch(request.req_kind) {
+ case REQ_CREATE:
+ PDEBUG("got REQ_CREATE\n");
+ 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);
+ PDEBUG("restarting %d\n", request.req_thread);
+ restart(request.req_thread);
+ break;
+ case REQ_FREE:
+ PDEBUG("got REQ_FREE\n");
+ pthread_handle_free(request.req_args.free.thread_id);
+ break;
+ case REQ_PROCESS_EXIT:
+ PDEBUG("got REQ_PROCESS_EXIT from %d, exit code = %d\n",
+ request.req_thread, request.req_args.exit.code);
+ pthread_handle_exit(request.req_thread,
+ request.req_args.exit.code);
+ break;
+ case REQ_MAIN_THREAD_EXIT:
+ PDEBUG("got REQ_MAIN_THREAD_EXIT\n");
+ 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:
+ PDEBUG("got REQ_POST\n");
+ __new_sem_post(request.req_args.post);
+ break;
+ case REQ_DEBUG:
+ PDEBUG("got REQ_DEBUG\n");
+ /* 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) {
+ PDEBUG("about to call raise(__pthread_sig_debug)\n");
+ raise(__pthread_sig_debug);
+ }
+ 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;
+ }
+ }
+ }
+}
+
+int __pthread_manager_event(void *arg)
+{
+ /* If we have special thread_self processing, initialize it. */
+#ifdef INIT_THREAD_SELF
+ INIT_THREAD_SELF(&__pthread_manager_thread, 1);
+#endif
+
+ /* Get the lock the manager will free once all is correctly set up. */
+ __pthread_lock (THREAD_GETMEM((&__pthread_manager_thread), p_lock), NULL);
+ /* Free it immediately. */
+ __pthread_unlock (THREAD_GETMEM((&__pthread_manager_thread), 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;
+ /* Initialize special thread_self processing, if any. */
+#ifdef INIT_THREAD_SELF
+ INIT_THREAD_SELF(self, self->p_nr);
+#endif
+ PDEBUG("\n");
+ /* 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 (__pthread_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);
+ }
+ /* 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(__libc_write(__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_exit(outcome);
+}
+
+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);
+}
+
+static int pthread_allocate_stack(const pthread_attr_t *attr,
+ pthread_descr default_new_thread,
+ int pagesize,
+ pthread_descr * out_new_thread,
+ char ** out_new_thread_bottom,
+ char ** out_guardaddr,
+ size_t * out_guardsize)
+{
+ pthread_descr new_thread;
+ char * new_thread_bottom;
+ char * guardaddr;
+ size_t stacksize, guardsize;
+
+ if (attr != NULL && attr->__stackaddr_set)
+ {
+ /* The user provided a stack. */
+ new_thread =
+ (pthread_descr) ((long)(attr->__stackaddr) & -sizeof(void *)) - 1;
+ new_thread_bottom = (char *) attr->__stackaddr - attr->__stacksize;
+ guardaddr = NULL;
+ guardsize = 0;
+ __pthread_nonstandard_stacks = 1;
+ }
+ else
+ {
+#ifdef __ARCH_HAS_MMU__
+ stacksize = STACK_SIZE - pagesize;
+ if (attr != NULL)
+ stacksize = MIN (stacksize, roundup(attr->__stacksize, pagesize));
+ /* Allocate space for stack and thread descriptor at default address */
+ new_thread = default_new_thread;
+ new_thread_bottom = (char *) (new_thread + 1) - stacksize;
+ if (mmap((caddr_t)((char *)(new_thread + 1) - INITIAL_STACK_SIZE),
+ INITIAL_STACK_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED | MAP_GROWSDOWN,
+ -1, 0) == MAP_FAILED)
+ /* Bad luck, this segment is already mapped. */
+ return -1;
+ /* We manage to get a stack. Now see whether we need a guard
+ and allocate it if necessary. Notice that the default
+ attributes (stack_size = STACK_SIZE - pagesize) do not need
+ a guard page, since the RLIMIT_STACK soft limit prevents stacks
+ from running into one another. */
+ if (stacksize == STACK_SIZE - pagesize)
+ {
+ /* We don't need a guard page. */
+ guardaddr = NULL;
+ guardsize = 0;
+ }
+ else
+ {
+ /* Put a bad page at the bottom of the stack */
+ guardsize = attr->__guardsize;
+ guardaddr = (void *)new_thread_bottom - guardsize;
+ if (mmap ((caddr_t) guardaddr, guardsize, 0, MAP_FIXED, -1, 0)
+ == MAP_FAILED)
+ {
+ /* We don't make this an error. */
+ guardaddr = NULL;
+ guardsize = 0;
+ }
+ }
+#else
+ /* We cannot mmap to this huge chunk of stack space when we don't have
+ * an MMU. Pretend we are using a user provided stack even if there was
+ * none provided by the user. Thus, we get around the mmap and reservation
+ * of a huge stack segment. -StS */
+
+ stacksize = INITIAL_STACK_SIZE;
+ /* The user may want to use a non-default stacksize */
+ if (attr != NULL)
+ {
+ stacksize = attr->__stacksize;
+ }
+
+ /* malloc a stack - memory from the bottom up */
+ if ((new_thread_bottom = malloc(stacksize)) == NULL)
+ {
+ /* bad luck, we cannot malloc any more */
+ return -1 ;
+ }
+ PDEBUG("malloced chunk: base=%p, size=0x%04x\n", new_thread_bottom, stacksize);
+
+ /* Set up the pointers. new_thread marks the TOP of the stack frame and
+ * the address of the pthread_descr struct at the same time. Therefore we
+ * must account for its size and fit it in the malloc()'ed block. The
+ * value of `new_thread' is then passed to clone() as the stack argument.
+ *
+ * ^ +------------------------+
+ * | | pthread_descr struct |
+ * | +------------------------+ <- new_thread
+ * malloc block | | |
+ * | | thread stack |
+ * | | |
+ * v +------------------------+ <- new_thread_bottom
+ *
+ * Note: The calculated value of new_thread must be word aligned otherwise
+ * the kernel chokes on a non-aligned stack frame. Choose the lower
+ * available word boundary.
+ */
+ new_thread = ((pthread_descr) ((int)(new_thread_bottom + stacksize) & -sizeof(void*))) - 1;
+ guardaddr = NULL;
+ guardsize = 0;
+
+ PDEBUG("thread stack: bos=%p, tos=%p\n", new_thread_bottom, new_thread);
+
+ /* check the initial thread stack boundaries so they don't overlap */
+ NOMMU_INITIAL_THREAD_BOUNDS((char *) new_thread, (char *) new_thread_bottom);
+
+ PDEBUG("initial stack: bos=%p, tos=%p\n", __pthread_initial_thread_bos,
+ __pthread_initial_thread_tos);
+
+ /* on non-MMU systems we always have non-standard stack frames */
+ __pthread_nonstandard_stacks = 1;
+
+#endif /* __ARCH_HAS_MMU__ */
+ }
+
+ /* Clear the thread data structure. */
+ memset (new_thread, '\0', sizeof (*new_thread));
+ *out_new_thread = new_thread;
+ *out_new_thread_bottom = new_thread_bottom;
+ *out_guardaddr = guardaddr;
+ *out_guardsize = guardsize;
+ 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 * new_thread_bottom;
+ pthread_t new_thread_id;
+ char *guardaddr = NULL;
+ size_t guardsize = 0;
+ int pagesize = __getpagesize();
+ int saved_errno = 0;
+
+ /* 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)
+ return EAGAIN;
+ if (__pthread_handles[sseg].h_descr != NULL)
+ continue;
+ if (pthread_allocate_stack(attr, thread_segment(sseg), pagesize,
+ &new_thread, &new_thread_bottom,
+ &guardaddr, &guardsize) == 0)
+ 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. */
+ 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;
+ new_thread->p_errnop = &new_thread->p_errno;
+ new_thread->p_h_errnop = &new_thread->p_h_errno;
+#ifdef __UCLIBC_HAS_XLOCALE__
+ /* Initialize thread's locale to the global locale. */
+ new_thread->locale = __global_locale;
+#endif /* __UCLIBC_HAS_XLOCALE__ */
+ new_thread->p_guardaddr = guardaddr;
+ new_thread->p_guardsize = guardsize;
+ new_thread->p_self = new_thread;
+ new_thread->p_nr = sseg;
+ /* 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;
+ /* 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. */
+
+
+ /* ******************************************************** */
+ /* This code was moved from below to cope with running threads
+ * on uClinux systems. See comment below...
+ * 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;
+ /* ********************************************************* */
+
+ 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. */
+ pid = clone(pthread_start_thread_event, (void **) new_thread,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
+ __pthread_sig_cancel, new_thread);
+
+ 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)
+ {
+ PDEBUG("cloning new_thread = %p\n", new_thread);
+ pid = clone(pthread_start_thread, (void **) new_thread,
+ CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND |
+ __pthread_sig_cancel, new_thread);
+ saved_errno = errno;
+ }
+ /* Check if cloning succeeded */
+ if (pid == -1) {
+ /********************************************************
+ * Code inserted to remove the thread from our list of active
+ * threads in case of failure (needed to cope with uClinux),
+ * See comment below. */
+ new_thread->p_nextlive->p_prevlive = new_thread->p_prevlive;
+ new_thread->p_prevlive->p_nextlive = new_thread->p_nextlive;
+ /********************************************************/
+
+ /* Free the stack if we allocated it */
+ if (attr == NULL || !attr->__stackaddr_set)
+ {
+#ifdef __ARCH_HAS_MMU__
+ if (new_thread->p_guardsize != 0)
+ munmap(new_thread->p_guardaddr, new_thread->p_guardsize);
+ munmap((caddr_t)((char *)(new_thread+1) - INITIAL_STACK_SIZE),
+ INITIAL_STACK_SIZE);
+#else
+ free(new_thread_bottom);
+#endif /* __ARCH_HAS_MMU__ */
+ }
+ __pthread_handles[sseg].h_descr = NULL;
+ __pthread_handles[sseg].h_bottom = NULL;
+ __pthread_handles_num--;
+ return errno;
+ }
+ PDEBUG("new thread pid = %d\n", pid);
+
+#if 0
+ /* ***********************************************************
+ This code has been moved before the call to clone(). In uClinux,
+ the use of wait on a semaphore is dependant upon that the child so
+ the child must be in the active threads list. This list is used in
+ pthread_find_self() to get the pthread_descr of self. So, if the
+ child calls sem_wait before this code is executed , it will hang
+ forever and initial_thread will instead be posted by a sem_post
+ call. */
+
+ /* 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;
+ /************************************************************/
+#endif
+
+ /* Set pid field of the new thread, in case we get there before the
+ child starts. */
+ new_thread->p_pid = pid;
+ /* We're all set */
+ *thread = new_thread_id;
+ 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;
+ char *h_bottom_save;
+
+ ASSERT(th->p_exited);
+ /* Make the handle invalid */
+ handle = thread_handle(th->p_tid);
+ __pthread_lock(&handle->h_lock, NULL);
+ h_bottom_save = handle->h_bottom;
+ handle->h_descr = NULL;
+ handle->h_bottom = (char *)(-1L);
+ __pthread_unlock(&handle->h_lock);
+#ifdef FREE_THREAD_SELF
+ FREE_THREAD_SELF(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 == &__pthread_initial_thread) return;
+#ifdef __ARCH_HAS_MMU__
+ if (!th->p_userstack)
+ {
+ /* Free the stack and thread descriptor area */
+ if (th->p_guardsize != 0)
+ munmap(th->p_guardaddr, th->p_guardsize);
+ munmap((caddr_t) ((char *)(th+1) - STACK_SIZE), STACK_SIZE);
+ }
+#else
+ /* For non-MMU systems we always malloc the stack, so free it here. -StS */
+ if (!th->p_userstack) {
+ free(h_bottom_save);
+ }
+#endif /* __ARCH_HAS_MMU__ */
+}
+
+/* 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;
+ PDEBUG("\n");
+
+ while ((pid = __libc_waitpid(-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 (invalid_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);
+ }
+}
+
+/* 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;
+ /* 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);
+ }
+ 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(__libc_write(__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 <= __pthread_manager_thread.p_priority) return;
+ param.sched_priority =
+ thread_prio < sched_get_priority_max(SCHED_FIFO)
+ ? thread_prio + 1 : thread_prio;
+ sched_setscheduler(__pthread_manager_thread.p_pid, SCHED_FIFO, &param);
+ __pthread_manager_thread.p_priority = thread_prio;
+}