diff options
Diffstat (limited to 'newlib/libc/sys/linux/linuxthreads/pthread.c')
| -rw-r--r-- | newlib/libc/sys/linux/linuxthreads/pthread.c | 1248 |
1 files changed, 0 insertions, 1248 deletions
diff --git a/newlib/libc/sys/linux/linuxthreads/pthread.c b/newlib/libc/sys/linux/linuxthreads/pthread.c deleted file mode 100644 index b42d9d60a..000000000 --- a/newlib/libc/sys/linux/linuxthreads/pthread.c +++ /dev/null @@ -1,1248 +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. */ - -/* Thread creation, initialization, and basic low-level routines */ - -#include <errno.h> -#include <stddef.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include <fcntl.h> -#include <sys/wait.h> -#include <sys/resource.h> -#include <sys/sysctl.h> -#include <shlib-compat.h> -#include "pthread.h" -#include "internals.h" -#include "spinlock.h" -#include "restart.h" -#include <machine/syscall.h> - -/* for threading we use processes so we require a few EL/IX level 2 and - level 3 syscalls. We only allow this file to see them to preserve - the interface. */ -#if defined(_ELIX_LEVEL) && _ELIX_LEVEL < 3 -static _syscall1_base(int,pipe,int *,filedes) -#endif /* _ELIX_LEVEL < 3 */ - -#if defined(_ELIX_LEVEL) && _ELIX_LEVEL < 2 -static _syscall2_base(int,setrlimit,int,resource,const struct rlimit *,rlp) -int on_exit (void (*fn)(int, void *), void *arg) -{ - register struct _atexit *p; - void (*x)(void) = (void (*)(void))fn; - -/* _REENT_SMALL on_exit() doesn't allow more than the required 32 entries. */ -#ifndef _REENT_SMALL - if ((p = _REENT->_atexit) == NULL) - _REENT->_atexit = p = &_REENT->_atexit0; - if (p->_ind >= _ATEXIT_SIZE) - { - if ((p = (struct _atexit *) malloc (sizeof *p)) == NULL) - return -1; - p->_ind = 0; - p->_fntypes = 0; - p->_next = _REENT->_atexit; - _REENT->_atexit = p; - } -#else - p = &_REENT->_atexit; - if (p->_ind >= _ATEXIT_SIZE) - return -1; -#endif - p->_fntypes |= (1 << p->_ind); - p->_fnargs[p->_ind] = arg; - p->_fns[p->_ind++] = x; - return 0; -} - -#endif /* _ELIX_LEVEL < 2 */ - -/* We need the global/static resolver state here. */ -#include <resolv.h> -#undef _res - -/* FIXME: for now, set up _res here */ -struct __res_state _res; - -/* Sanity check. */ -#if __ASSUME_REALTIME_SIGNALS && !defined __SIGRTMIN -# error "This must not happen; new kernel assumed but old headers" -#endif - -/* These variables are used by the setup code. */ - -/* Descriptor of the initial thread */ - -struct _pthread_descr_struct __pthread_initial_thread = { - { - { - &__pthread_initial_thread /* pthread_descr self */ - } - }, - &__pthread_initial_thread, /* pthread_descr p_nextlive */ - &__pthread_initial_thread, /* pthread_descr p_prevlive */ - NULL, /* pthread_descr p_nextwaiting */ - NULL, /* pthread_descr p_nextlock */ - PTHREAD_THREADS_MAX, /* pthread_t p_tid */ - 0, /* int p_pid */ - 0, /* int p_priority */ - &__pthread_handles[0].h_lock, /* struct _pthread_fastlock * p_lock */ - 0, /* int p_signal */ - NULL, /* sigjmp_buf * p_signal_buf */ - NULL, /* sigjmp_buf * p_cancel_buf */ - 0, /* char p_terminated */ - 0, /* char p_detached */ - 0, /* char p_exited */ - NULL, /* void * p_retval */ - 0, /* int p_retval */ - NULL, /* pthread_descr p_joining */ - NULL, /* struct _pthread_cleanup_buffer * p_cleanup */ - 0, /* char p_cancelstate */ - 0, /* char p_canceltype */ - 0, /* char p_canceled */ - &__pthread_initial_thread.p_reent, /* struct _reent *p_reentp */ - _REENT_INIT(__pthread_initial_thread.p_reent), /* struct _reent p_reent */ - NULL, /* int *p_h_errnop */ - 0, /* int p_h_errno */ - NULL, /* char * p_in_sighandler */ - 0, /* char p_sigwaiting */ - PTHREAD_START_ARGS_INITIALIZER(NULL), - /* struct pthread_start_args p_start_args */ - {NULL}, /* void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE] */ - {NULL}, /* void * p_libc_specific[_LIBC_TSD_KEY_N] */ - 1, /* int p_userstack */ - NULL, /* void * p_guardaddr */ - 0, /* size_t p_guardsize */ - 0, /* Always index 0 */ - 0, /* int p_report_events */ - {{{0, }}, 0, NULL}, /* td_eventbuf_t p_eventbuf */ - __ATOMIC_INITIALIZER, /* struct pthread_atomic p_resume_count */ - 0, /* char p_woken_by_cancel */ - 0, /* char p_condvar_avail */ - 0, /* char p_sem_avail */ - NULL, /* struct pthread_extricate_if *p_extricate */ - NULL, /* pthread_readlock_info *p_readlock_list; */ - NULL, /* pthread_readlock_info *p_readlock_free; */ - 0 /* int p_untracked_readlock_count; */ -}; - -/* Descriptor of the manager thread; none of this is used but the error - variables, the p_pid and p_priority fields, - and the address for identification. */ - -struct _pthread_descr_struct __pthread_manager_thread = { - { - { - &__pthread_manager_thread /* pthread_descr self */ - } - }, - NULL, /* pthread_descr p_nextlive */ - NULL, /* pthread_descr p_prevlive */ - NULL, /* pthread_descr p_nextwaiting */ - NULL, /* pthread_descr p_nextlock */ - 0, /* int p_tid */ - 0, /* int p_pid */ - 0, /* int p_priority */ - &__pthread_handles[1].h_lock, /* struct _pthread_fastlock * p_lock */ - 0, /* int p_signal */ - NULL, /* sigjmp_buf * p_signal_buf */ - NULL, /* sigjmp_buf * p_cancel_buf */ - 0, /* char p_terminated */ - 0, /* char p_detached */ - 0, /* char p_exited */ - NULL, /* void * p_retval */ - 0, /* int p_retval */ - NULL, /* pthread_descr p_joining */ - NULL, /* struct _pthread_cleanup_buffer * p_cleanup */ - 0, /* char p_cancelstate */ - 0, /* char p_canceltype */ - 0, /* char p_canceled */ - &__pthread_manager_thread.p_reent, /* struct _reent *p_reentp */ - _REENT_INIT(__pthread_manager_thread.p_reent), /* struct _reent p_reent */ - NULL, /* int *p_h_errnop */ - 0, /* int p_h_errno */ - NULL, /* char * p_in_sighandler */ - 0, /* char p_sigwaiting */ - PTHREAD_START_ARGS_INITIALIZER(__pthread_manager), - /* struct pthread_start_args p_start_args */ - {NULL}, /* void ** p_specific[PTHREAD_KEY_1STLEVEL_SIZE] */ - {NULL}, /* void * p_libc_specific[_LIBC_TSD_KEY_N] */ - 0, /* int p_userstack */ - NULL, /* void * p_guardaddr */ - 0, /* size_t p_guardsize */ - 1, /* Always index 1 */ - 0, /* int p_report_events */ - {{{0, }}, 0, NULL}, /* td_eventbuf_t p_eventbuf */ - __ATOMIC_INITIALIZER, /* struct pthread_atomic p_resume_count */ - 0, /* char p_woken_by_cancel */ - 0, /* char p_condvar_avail */ - 0, /* char p_sem_avail */ - NULL, /* struct pthread_extricate_if *p_extricate */ - NULL, /* pthread_readlock_info *p_readlock_list; */ - NULL, /* pthread_readlock_info *p_readlock_free; */ - 0 /* int p_untracked_readlock_count; */ -}; - -/* Pointer to the main thread (the father of the thread manager thread) */ -/* Originally, this is the initial thread, but this changes after fork() */ - -pthread_descr __pthread_main_thread = &__pthread_initial_thread; - -/* Limit between the stack of the initial thread (above) and the - stacks of other threads (below). Aligned on a STACK_SIZE boundary. */ - -char *__pthread_initial_thread_bos; - -/* File descriptor for sending requests to the thread manager. */ -/* Initially -1, meaning that the thread manager is not running. */ - -int __pthread_manager_request = -1; - -/* Other end of the pipe for sending requests to the thread manager. */ - -int __pthread_manager_reader; - -/* Limits of the thread manager stack */ - -char *__pthread_manager_thread_bos; -char *__pthread_manager_thread_tos; - -/* For process-wide exit() */ - -int __pthread_exit_requested; -int __pthread_exit_code; - -/* Maximum stack size. */ -size_t __pthread_max_stacksize; - -/* Nozero if the machine has more than one processor. */ -int __pthread_smp_kernel; - - -#if !__ASSUME_REALTIME_SIGNALS -/* Pointers that select new or old suspend/resume functions - based on availability of rt signals. */ - -void (*__pthread_restart)(pthread_descr) = __pthread_restart_old; -void (*__pthread_suspend)(pthread_descr) = __pthread_suspend_old; -int (*__pthread_timedsuspend)(pthread_descr, const struct timespec *) = __pthread_timedsuspend_old; -#endif /* __ASSUME_REALTIME_SIGNALS */ - -/* Communicate relevant LinuxThreads constants to gdb */ - -const int __pthread_threads_max = PTHREAD_THREADS_MAX; -const int __pthread_sizeof_handle = sizeof(struct pthread_handle_struct); -const int __pthread_offsetof_descr = offsetof(struct pthread_handle_struct, - h_descr); -const int __pthread_offsetof_pid = offsetof(struct _pthread_descr_struct, - p_pid); -const int __linuxthreads_pthread_sizeof_descr - = sizeof(struct _pthread_descr_struct); - -/* Forward declarations */ - -static void pthread_onexit_process(int retcode, void *arg); -#ifndef HAVE_Z_NODELETE -static void pthread_atexit_process(void *arg, int retcode); -static void pthread_atexit_retcode(void *arg, int retcode); -#endif -static void pthread_handle_sigcancel(int sig); -static void pthread_handle_sigrestart(int sig); -static void pthread_handle_sigdebug(int sig); - -/* CPU clock handling. */ -#if HP_TIMING_AVAIL -extern hp_timing_t _dl_cpuclock_offset; -#endif - -/* Signal numbers used for the communication. - In these variables we keep track of the used variables. If the - platform does not support any real-time signals we will define the - values to some unreasonable value which will signal failing of all - the functions below. */ -#ifndef __SIGRTMIN -static int current_rtmin = -1; -static int current_rtmax = -1; -int __pthread_sig_restart = SIGUSR1; -int __pthread_sig_cancel = SIGUSR2; -int __pthread_sig_debug; -#else -static int current_rtmin; -static int current_rtmax; - -#if __SIGRTMAX - __SIGRTMIN >= 3 -int __pthread_sig_restart = __SIGRTMIN; -int __pthread_sig_cancel = __SIGRTMIN + 1; -int __pthread_sig_debug = __SIGRTMIN + 2; -#else -int __pthread_sig_restart = SIGUSR1; -int __pthread_sig_cancel = SIGUSR2; -int __pthread_sig_debug; -#endif - -static int rtsigs_initialized; - -#if !__ASSUME_REALTIME_SIGNALS -# include "testrtsig.h" -#endif - -static void -init_rtsigs (void) -{ -#if !__ASSUME_REALTIME_SIGNALS - if (__builtin_expect (!kernel_has_rtsig (), 0)) - { - current_rtmin = -1; - current_rtmax = -1; -# if __SIGRTMAX - __SIGRTMIN >= 3 - __pthread_sig_restart = SIGUSR1; - __pthread_sig_cancel = SIGUSR2; - __pthread_sig_debug = 0; -# endif - } - else -#endif /* __ASSUME_REALTIME_SIGNALS */ - { -#if __SIGRTMAX - __SIGRTMIN >= 3 - current_rtmin = __SIGRTMIN + 3; -# if !__ASSUME_REALTIME_SIGNALS - __pthread_restart = __pthread_restart_new; - __pthread_suspend = __pthread_wait_for_restart_signal; - __pthread_timedsuspend = __pthread_timedsuspend_new; -# endif /* __ASSUME_REALTIME_SIGNALS */ -#else - current_rtmin = __SIGRTMIN; -#endif - - current_rtmax = __SIGRTMAX; - } - - rtsigs_initialized = 1; -} -#endif - -/* Return number of available real-time signal with highest priority. */ -int -__libc_current_sigrtmin (void) -{ -#ifdef __SIGRTMIN - if (__builtin_expect (!rtsigs_initialized, 0)) - init_rtsigs (); -#endif - return current_rtmin; -} - -/* Return number of available real-time signal with lowest priority. */ -int -__libc_current_sigrtmax (void) -{ -#ifdef __SIGRTMIN - if (__builtin_expect (!rtsigs_initialized, 0)) - init_rtsigs (); -#endif - return current_rtmax; -} - -/* Allocate real-time signal with highest/lowest available - priority. Please note that we don't use a lock since we assume - this function to be called at program start. */ -int -__libc_allocate_rtsig (int high) -{ -#ifndef __SIGRTMIN - return -1; -#else - if (__builtin_expect (!rtsigs_initialized, 0)) - init_rtsigs (); - if (__builtin_expect (current_rtmin == -1, 0) - || __builtin_expect (current_rtmin > current_rtmax, 0)) - /* We don't have anymore signal available. */ - return -1; - - return high ? current_rtmin++ : current_rtmax--; -#endif -} - -/* The function we use to get the kernel revision. */ -extern int __sysctl (int *name, int nlen, void *oldval, size_t *oldlenp, - void *newval, size_t newlen); - -/* Test whether the machine has more than one processor. This is not the - best test but good enough. More complicated tests would require `malloc' - which is not available at that time. */ -static int -is_smp_system (void) -{ - static const int sysctl_args[] = { CTL_KERN, KERN_VERSION }; - char buf[512]; - size_t reslen = sizeof (buf); - - /* Try reading the number using `sysctl' first. */ - if (__sysctl ((int *) sysctl_args, - sizeof (sysctl_args) / sizeof (sysctl_args[0]), - buf, &reslen, NULL, 0) < 0) - { - /* This was not successful. Now try reading the /proc filesystem. */ - int fd = __open ("/proc/sys/kernel/version", O_RDONLY); - if (__builtin_expect (fd, 0) == -1 - || (reslen = __read (fd, buf, sizeof (buf))) <= 0) - /* This also didn't work. We give up and say it's a UP machine. */ - buf[0] = '\0'; - - __close (fd); - } - - return strstr (buf, "SMP") != NULL; -} - - -/* Initialize the pthread library. - Initialization is split in two functions: - - a constructor function that blocks the __pthread_sig_restart signal - (must do this very early, since the program could capture the signal - mask with e.g. sigsetjmp before creating the first thread); - - a regular function called from pthread_create when needed. */ - -static void pthread_initialize(void) __attribute__((constructor)); - -#ifndef HAVE_Z_NODELETE -extern void *__dso_handle __attribute__ ((weak)); -#endif - - -/* Do some minimal initialization which has to be done during the - startup of the C library. */ -void -__pthread_initialize_minimal(void) -{ - /* If we have special thread_self processing, initialize that for the - main thread now. */ -#ifdef INIT_THREAD_SELF - INIT_THREAD_SELF(&__pthread_initial_thread, 0); -#endif -#if HP_TIMING_AVAIL - __pthread_initial_thread.p_cpuclock_offset = _dl_cpuclock_offset; -#endif -} - - -void -__pthread_init_max_stacksize(void) -{ - struct rlimit limit; - size_t max_stack; - - getrlimit(RLIMIT_STACK, &limit); -#ifdef FLOATING_STACKS - if (limit.rlim_cur == RLIM_INFINITY) - limit.rlim_cur = ARCH_STACK_MAX_SIZE; -# ifdef NEED_SEPARATE_REGISTER_STACK - max_stack = limit.rlim_cur / 2; -# else - max_stack = limit.rlim_cur; -# endif -#else - /* Play with the stack size limit to make sure that no stack ever grows - beyond STACK_SIZE minus one page (to act as a guard page). */ -# ifdef NEED_SEPARATE_REGISTER_STACK - /* STACK_SIZE bytes hold both the main stack and register backing - store. The rlimit value applies to each individually. */ - max_stack = STACK_SIZE/2 - __getpagesize (); -# else - max_stack = STACK_SIZE - __getpagesize(); -# endif - if (limit.rlim_cur > max_stack) { - limit.rlim_cur = max_stack; - __libc_setrlimit(RLIMIT_STACK, &limit); - } -#endif - __pthread_max_stacksize = max_stack; -} - - -static void pthread_initialize(void) -{ - struct sigaction sa; - sigset_t mask; - - /* If already done (e.g. by a constructor called earlier!), bail out */ - if (__pthread_initial_thread_bos != NULL) return; -#ifdef TEST_FOR_COMPARE_AND_SWAP - /* Test if compare-and-swap is available */ - __pthread_has_cas = compare_and_swap_is_available(); -#endif -#ifdef FLOATING_STACKS - /* We don't need to know the bottom of the stack. Give the pointer some - value to signal that initialization happened. */ - __pthread_initial_thread_bos = (void *) -1l; -#else - /* Determine stack size limits . */ - __pthread_init_max_stacksize (); -# ifdef _STACK_GROWS_UP - /* The initial thread already has all the stack it needs */ - __pthread_initial_thread_bos = (char *) - ((long)CURRENT_STACK_FRAME &~ (STACK_SIZE - 1)); -# else - /* For the initial stack, reserve at least STACK_SIZE bytes of stack - below the current stack address, and align that on a - STACK_SIZE boundary. */ - __pthread_initial_thread_bos = - (char *)(((long)CURRENT_STACK_FRAME - 2 * STACK_SIZE) & ~(STACK_SIZE - 1)); -# endif -#endif - /* Update the descriptor for the initial thread. */ - __pthread_initial_thread.p_pid = __getpid(); - /* Likewise for the resolver state _res. */ - __pthread_initial_thread.p_resp = &_res; -#ifdef __SIGRTMIN - /* Initialize real-time signals. */ - init_rtsigs (); -#endif - /* Setup signal handlers for the initial thread. - Since signal handlers are shared between threads, these settings - will be inherited by all other threads. */ - sa.sa_handler = pthread_handle_sigrestart; - sigemptyset(&sa.sa_mask); - sa.sa_flags = 0; - __libc_sigaction(__pthread_sig_restart, &sa, NULL); - sa.sa_handler = pthread_handle_sigcancel; - // sa.sa_flags = 0; - __libc_sigaction(__pthread_sig_cancel, &sa, NULL); - if (__pthread_sig_debug > 0) { - sa.sa_handler = pthread_handle_sigdebug; - sigemptyset(&sa.sa_mask); - // sa.sa_flags = 0; - __libc_sigaction(__pthread_sig_debug, &sa, NULL); - } - /* Initially, block __pthread_sig_restart. Will be unblocked on demand. */ - sigemptyset(&mask); - sigaddset(&mask, __pthread_sig_restart); - sigprocmask(SIG_BLOCK, &mask, NULL); - /* Register an exit function to kill all other threads. */ - /* Do it early so that user-registered atexit functions are called - before pthread_*exit_process. */ -#ifndef HAVE_Z_NODELETE - if (__builtin_expect (&__dso_handle != NULL, 1)) - __cxa_atexit ((void (*) (void *)) pthread_atexit_process, NULL, - __dso_handle); - else -#endif - on_exit (pthread_onexit_process, NULL); - /* How many processors. */ - __pthread_smp_kernel = is_smp_system (); -} - -void __pthread_initialize(void) -{ - pthread_initialize(); -} - -int __pthread_initialize_manager(void) -{ - int manager_pipe[2]; - int pid; - struct pthread_request request; - -#ifndef HAVE_Z_NODELETE - if (__builtin_expect (&__dso_handle != NULL, 1)) - __cxa_atexit ((void (*) (void *)) pthread_atexit_retcode, NULL, - __dso_handle); -#endif - - if (__pthread_max_stacksize == 0) - __pthread_init_max_stacksize (); - /* If basic initialization not done yet (e.g. we're called from a - constructor run before our constructor), do it now */ - if (__pthread_initial_thread_bos == NULL) pthread_initialize(); - /* Setup stack for thread manager */ - __pthread_manager_thread_bos = malloc(THREAD_MANAGER_STACK_SIZE); - if (__pthread_manager_thread_bos == NULL) return -1; - __pthread_manager_thread_tos = - __pthread_manager_thread_bos + THREAD_MANAGER_STACK_SIZE; - /* Setup pipe to communicate with thread manager */ - if (__libc_pipe(manager_pipe) == -1) { - free(__pthread_manager_thread_bos); - return -1; - } - /* Start the thread manager */ - pid = 0; - if (__builtin_expect (__pthread_initial_thread.p_report_events, 0)) - { - /* It's a bit more complicated. We have to report the creation of - the manager thread. */ - int idx = __td_eventword (TD_CREATE); - uint32_t mask = __td_eventmask (TD_CREATE); - - if ((mask & (__pthread_threads_events.event_bits[idx] - | __pthread_initial_thread.p_eventbuf.eventmask.event_bits[idx])) - != 0) - { - __pthread_lock(__pthread_manager_thread.p_lock, NULL); - -#ifdef NEED_SEPARATE_REGISTER_STACK - pid = __clone2(__pthread_manager_event, - (void **) __pthread_manager_thread_bos, - THREAD_MANAGER_STACK_SIZE, - CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, - (void *)(long)manager_pipe[0]); -#elif _STACK_GROWS_UP - pid = __clone(__pthread_manager_event, - (void **) __pthread_manager_thread_bos, - CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, - (void *)(long)manager_pipe[0]); -#else - pid = __clone(__pthread_manager_event, - (void **) __pthread_manager_thread_tos, - CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, - (void *)(long)manager_pipe[0]); -#endif - - 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. */ - __pthread_manager_thread.p_eventbuf.eventdata = - &__pthread_manager_thread; - __pthread_manager_thread.p_eventbuf.eventnum = TD_CREATE; - __pthread_last_event = &__pthread_manager_thread; - __pthread_manager_thread.p_tid = 2* PTHREAD_THREADS_MAX + 1; - __pthread_manager_thread.p_pid = pid; - - /* Now call the function which signals the event. */ - __linuxthreads_create_event (); - } - - /* Now restart the thread. */ - __pthread_unlock(__pthread_manager_thread.p_lock); - } - } - - if (__builtin_expect (pid, 0) == 0) - { -#ifdef NEED_SEPARATE_REGISTER_STACK - pid = __clone2(__pthread_manager, (void **) __pthread_manager_thread_bos, - THREAD_MANAGER_STACK_SIZE, - CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, - (void *)(long)manager_pipe[0]); -#elif _STACK_GROWS_UP - pid = __clone(__pthread_manager, (void **) __pthread_manager_thread_bos, - CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, - (void *)(long)manager_pipe[0]); -#else - pid = __clone(__pthread_manager, (void **) __pthread_manager_thread_tos, - CLONE_VM | CLONE_FS | CLONE_FILES | CLONE_SIGHAND, - (void *)(long)manager_pipe[0]); -#endif - } - if (__builtin_expect (pid, 0) == -1) { - free(__pthread_manager_thread_bos); - __libc_close(manager_pipe[0]); - __libc_close(manager_pipe[1]); - return -1; - } - __pthread_manager_request = manager_pipe[1]; /* writing end */ - __pthread_manager_reader = manager_pipe[0]; /* reading end */ - __pthread_manager_thread.p_tid = 2* PTHREAD_THREADS_MAX + 1; - __pthread_manager_thread.p_pid = pid; - /* Make gdb aware of new thread manager */ - if (__builtin_expect (__pthread_threads_debug, 0) && __pthread_sig_debug > 0) - { - raise(__pthread_sig_debug); - /* We suspend ourself and gdb will wake us up when it is - ready to handle us. */ - __pthread_wait_for_restart_signal(thread_self()); - } - /* Synchronize debugging of the thread manager */ - request.req_kind = REQ_DEBUG; - TEMP_FAILURE_RETRY(__libc_write(__pthread_manager_request, - (char *) &request, sizeof(request))); - return 0; -} - -/* Thread creation */ - -int __pthread_create_2_1(pthread_t *thread, const pthread_attr_t *attr, - void * (*start_routine)(void *), void *arg) -{ - pthread_descr self = thread_self(); - struct pthread_request request; - int retval; - if (__builtin_expect (__pthread_manager_request, 0) < 0) { - if (__pthread_initialize_manager() < 0) return EAGAIN; - } - request.req_thread = self; - request.req_kind = REQ_CREATE; - request.req_args.create.attr = attr; - request.req_args.create.fn = start_routine; - request.req_args.create.arg = arg; - sigprocmask(SIG_SETMASK, (const sigset_t *) NULL, - &request.req_args.create.mask); - TEMP_FAILURE_RETRY(__libc_write(__pthread_manager_request, - (char *) &request, sizeof(request))); - suspend(self); - retval = THREAD_GETMEM(self, p_retcode); - if (__builtin_expect (retval, 0) == 0) - *thread = (pthread_t) THREAD_GETMEM(self, p_retval); - return retval; -} - -versioned_symbol (libpthread, __pthread_create_2_1, pthread_create, GLIBC_2_1); - -#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1) - -int __pthread_create_2_0(pthread_t *thread, const pthread_attr_t *attr, - void * (*start_routine)(void *), void *arg) -{ - /* The ATTR attribute is not really of type `pthread_attr_t *'. It has - the old size and access to the new members might crash the program. - We convert the struct now. */ - pthread_attr_t new_attr; - - if (attr != NULL) - { - size_t ps = __getpagesize (); - - memcpy (&new_attr, attr, - (size_t) &(((pthread_attr_t*)NULL)->__guardsize)); - new_attr.__guardsize = ps; - new_attr.__stackaddr_set = 0; - new_attr.__stackaddr = NULL; - new_attr.__stacksize = STACK_SIZE - ps; - attr = &new_attr; - } - return __pthread_create_2_1 (thread, attr, start_routine, arg); -} -compat_symbol (libpthread, __pthread_create_2_0, pthread_create, GLIBC_2_0); -#endif - -/* Simple operations on thread identifiers */ - -pthread_t pthread_self(void) -{ - pthread_descr self = thread_self(); - return THREAD_GETMEM(self, p_tid); -} - -int pthread_equal(pthread_t thread1, pthread_t thread2) -{ - return thread1 == thread2; -} - -/* Helper function for thread_self in the case of user-provided stacks */ - -#ifndef THREAD_SELF - -pthread_descr __pthread_find_self(void) -{ - char * sp = CURRENT_STACK_FRAME; - pthread_handle h; - - /* __pthread_handles[0] is the initial thread, __pthread_handles[1] is - the manager threads handled specially in thread_self(), so start at 2 */ - h = __pthread_handles + 2; - while (! (sp <= (char *) h->h_descr && sp >= h->h_bottom)) h++; - return h->h_descr; -} - -#else - -static pthread_descr thread_self_stack(void) -{ - char *sp = CURRENT_STACK_FRAME; - pthread_handle h; - - if (sp >= __pthread_manager_thread_bos && sp < __pthread_manager_thread_tos) - return &__pthread_manager_thread; - h = __pthread_handles + 2; - while (! (sp <= (char *) h->h_descr && sp >= h->h_bottom)) - h++; - return h->h_descr; -} - -#endif - -/* Thread scheduling */ - -int pthread_setschedparam(pthread_t thread, int policy, - const struct sched_param *param) -{ - pthread_handle handle = thread_handle(thread); - pthread_descr th; - - __pthread_lock(&handle->h_lock, NULL); - if (__builtin_expect (invalid_handle(handle, thread), 0)) { - __pthread_unlock(&handle->h_lock); - return ESRCH; - } - th = handle->h_descr; - if (__builtin_expect (__sched_setscheduler(th->p_pid, policy, param) == -1, - 0)) { - __pthread_unlock(&handle->h_lock); - return errno; - } - th->p_priority = policy == SCHED_OTHER ? 0 : param->sched_priority; - __pthread_unlock(&handle->h_lock); - if (__pthread_manager_request >= 0) - __pthread_manager_adjust_prio(th->p_priority); - return 0; -} - -int pthread_getschedparam(pthread_t thread, int *policy, - struct sched_param *param) -{ - pthread_handle handle = thread_handle(thread); - int pid, pol; - - __pthread_lock(&handle->h_lock, NULL); - if (__builtin_expect (invalid_handle(handle, thread), 0)) { - __pthread_unlock(&handle->h_lock); - return ESRCH; - } - pid = handle->h_descr->p_pid; - __pthread_unlock(&handle->h_lock); - pol = __sched_getscheduler(pid); - if (__builtin_expect (pol, 0) == -1) return errno; - if (__sched_getparam(pid, param) == -1) return errno; - *policy = pol; - return 0; -} - -int __pthread_yield (void) -{ - /* For now this is equivalent with the POSIX call. */ - return sched_yield (); -} -weak_alias (__pthread_yield, pthread_yield) - -/* Process-wide exit() request */ - -static void pthread_onexit_process(int retcode, void *arg) -{ - if (__builtin_expect (__pthread_manager_request, 0) >= 0) { - struct pthread_request request; - pthread_descr self = thread_self(); - - request.req_thread = self; - request.req_kind = REQ_PROCESS_EXIT; - request.req_args.exit.code = retcode; - TEMP_FAILURE_RETRY(__libc_write(__pthread_manager_request, - (char *) &request, sizeof(request))); - suspend(self); - /* Main thread should accumulate times for thread manager and its - children, so that timings for main thread account for all threads. */ - if (self == __pthread_main_thread) - { - __waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE); - /* Since all threads have been asynchronously terminated - (possibly holding locks), free cannot be used any more. */ - /*free (__pthread_manager_thread_bos);*/ - __pthread_manager_thread_bos = __pthread_manager_thread_tos = NULL; - } - } -} - -#ifndef HAVE_Z_NODELETE -static int __pthread_atexit_retcode; - -static void pthread_atexit_process(void *arg, int retcode) -{ - pthread_onexit_process (retcode ?: __pthread_atexit_retcode, arg); -} - -static void pthread_atexit_retcode(void *arg, int retcode) -{ - __pthread_atexit_retcode = retcode; -} -#endif - -/* The handler for the RESTART signal just records the signal received - in the thread descriptor, and optionally performs a siglongjmp - (for pthread_cond_timedwait). */ - -static void pthread_handle_sigrestart(int sig) -{ - pthread_descr self = thread_self(); - THREAD_SETMEM(self, p_signal, sig); - if (THREAD_GETMEM(self, p_signal_jmp) != NULL) - siglongjmp(*THREAD_GETMEM(self, p_signal_jmp), 1); -} - -/* The handler for the CANCEL signal checks for cancellation - (in asynchronous mode), for process-wide exit and exec requests. - For the thread manager thread, redirect the signal to - __pthread_manager_sighandler. */ - -static void pthread_handle_sigcancel(int sig) -{ - pthread_descr self = thread_self(); - sigjmp_buf * jmpbuf; - - if (self == &__pthread_manager_thread) - { -#ifdef THREAD_SELF - /* A new thread might get a cancel signal before it is fully - initialized, so that the thread register might still point to the - manager thread. Double check that this is really the manager - thread. */ - pthread_descr real_self = thread_self_stack(); - if (real_self == &__pthread_manager_thread) - { - __pthread_manager_sighandler(sig); - return; - } - /* Oops, thread_self() isn't working yet.. */ - self = real_self; -# ifdef INIT_THREAD_SELF - INIT_THREAD_SELF(self, self->p_nr); -# endif -#else - __pthread_manager_sighandler(sig); - return; -#endif - } - if (__builtin_expect (__pthread_exit_requested, 0)) { - /* Main thread should accumulate times for thread manager and its - children, so that timings for main thread account for all threads. */ - if (self == __pthread_main_thread) - __waitpid(__pthread_manager_thread.p_pid, NULL, __WCLONE); - _exit(__pthread_exit_code); - } - if (__builtin_expect (THREAD_GETMEM(self, p_canceled), 0) - && THREAD_GETMEM(self, p_cancelstate) == PTHREAD_CANCEL_ENABLE) { - if (THREAD_GETMEM(self, p_canceltype) == PTHREAD_CANCEL_ASYNCHRONOUS) - __pthread_do_exit(PTHREAD_CANCELED, CURRENT_STACK_FRAME); - jmpbuf = THREAD_GETMEM(self, p_cancel_jmp); - if (jmpbuf != NULL) { - THREAD_SETMEM(self, p_cancel_jmp, NULL); - siglongjmp(*jmpbuf, 1); - } - } -} - -/* Handler for the DEBUG signal. - The debugging strategy is as follows: - On reception of a REQ_DEBUG request (sent by new threads created to - the thread manager under debugging mode), the thread manager throws - __pthread_sig_debug to itself. The debugger (if active) intercepts - this signal, takes into account new threads and continue execution - of the thread manager by propagating the signal because it doesn't - know what it is specifically done for. In the current implementation, - the thread manager simply discards it. */ - -static void pthread_handle_sigdebug(int sig) -{ - /* Nothing */ -} - -/* Reset the state of the thread machinery after a fork(). - Close the pipe used for requests and set the main thread to the forked - thread. - Notice that we can't free the stack segments, as the forked thread - may hold pointers into them. */ - -void __pthread_reset_main_thread(void) -{ - pthread_descr self = thread_self(); - struct rlimit limit; - - if (__pthread_manager_request != -1) { - /* Free the thread manager stack */ - free(__pthread_manager_thread_bos); - __pthread_manager_thread_bos = __pthread_manager_thread_tos = NULL; - /* Close the two ends of the pipe */ - __libc_close(__pthread_manager_request); - __libc_close(__pthread_manager_reader); - __pthread_manager_request = __pthread_manager_reader = -1; - } - - /* Update the pid of the main thread */ - THREAD_SETMEM(self, p_pid, __getpid()); - /* Make the forked thread the main thread */ - __pthread_main_thread = self; - THREAD_SETMEM(self, p_nextlive, self); - THREAD_SETMEM(self, p_prevlive, self); - /* Now this thread modifies the global variables. */ - THREAD_SETMEM(self, p_resp, &_res); - - if (getrlimit (RLIMIT_STACK, &limit) == 0 - && limit.rlim_cur != limit.rlim_max) { - limit.rlim_cur = limit.rlim_max; - __libc_setrlimit(RLIMIT_STACK, &limit); - } -} - -/* Process-wide exec() request */ - -#if !defined(_ELIX_LEVEL) || _ELIX_LEVEL >= 2 - -void __pthread_kill_other_threads_np(void) -{ - struct sigaction sa; - /* Terminate all other threads and thread manager */ - pthread_onexit_process(0, NULL); - /* Make current thread the main thread in case the calling thread - changes its mind, does not exec(), and creates new threads instead. */ - __pthread_reset_main_thread(); - - /* Reset the signal handlers behaviour for the signals the - implementation uses since this would be passed to the new - process. */ - sigemptyset(&sa.sa_mask); - sa.sa_flags = 0; - sa.sa_handler = SIG_DFL; - __libc_sigaction(__pthread_sig_restart, &sa, NULL); - __libc_sigaction(__pthread_sig_cancel, &sa, NULL); - if (__pthread_sig_debug > 0) - __libc_sigaction(__pthread_sig_debug, &sa, NULL); -} -weak_alias (__pthread_kill_other_threads_np, pthread_kill_other_threads_np) - -#endif /* !_ELIX_LEVEL || _ELIX_LEVEL >= 2 */ - -/* Concurrency symbol level. */ -static int current_level; - -int __pthread_setconcurrency(int level) -{ - /* We don't do anything unless we have found a useful interpretation. */ - current_level = level; - return 0; -} -weak_alias (__pthread_setconcurrency, pthread_setconcurrency) - -int __pthread_getconcurrency(void) -{ - return current_level; -} -weak_alias (__pthread_getconcurrency, pthread_getconcurrency) - -/* Primitives for controlling thread execution */ - -void __pthread_wait_for_restart_signal(pthread_descr self) -{ - sigset_t mask; - - sigprocmask(SIG_SETMASK, NULL, &mask); /* Get current signal mask */ - sigdelset(&mask, __pthread_sig_restart); /* Unblock the restart signal */ - THREAD_SETMEM(self, p_signal, 0); - do { - sigsuspend(&mask); /* Wait for signal */ - } while (THREAD_GETMEM(self, p_signal) !=__pthread_sig_restart); - - READ_MEMORY_BARRIER(); /* See comment in __pthread_restart_new */ -} - -#if !__ASSUME_REALTIME_SIGNALS -/* The _old variants are for 2.0 and early 2.1 kernels which don't have RT - signals. - On these kernels, we use SIGUSR1 and SIGUSR2 for restart and cancellation. - Since the restart signal does not queue, we use an atomic counter to create - queuing semantics. This is needed to resolve a rare race condition in - pthread_cond_timedwait_relative. */ - -void __pthread_restart_old(pthread_descr th) -{ - if (atomic_increment(&th->p_resume_count) == -1) - kill(th->p_pid, __pthread_sig_restart); -} - -void __pthread_suspend_old(pthread_descr self) -{ - if (atomic_decrement(&self->p_resume_count) <= 0) - __pthread_wait_for_restart_signal(self); -} - -int -__pthread_timedsuspend_old(pthread_descr self, const struct timespec *abstime) -{ - sigset_t unblock, initial_mask; - int was_signalled = 0; - sigjmp_buf jmpbuf; - - if (atomic_decrement(&self->p_resume_count) == 0) { - /* Set up a longjmp handler for the restart signal, unblock - the signal and sleep. */ - - if (sigsetjmp(jmpbuf, 1) == 0) { - THREAD_SETMEM(self, p_signal_jmp, &jmpbuf); - THREAD_SETMEM(self, p_signal, 0); - /* Unblock the restart signal */ - sigemptyset(&unblock); - sigaddset(&unblock, __pthread_sig_restart); - sigprocmask(SIG_UNBLOCK, &unblock, &initial_mask); - - while (1) { - struct timeval now; - struct timespec reltime; - - /* Compute a time offset relative to now. */ - __gettimeofday (&now, NULL); - reltime.tv_nsec = abstime->tv_nsec - now.tv_usec * 1000; - reltime.tv_sec = abstime->tv_sec - now.tv_sec; - if (reltime.tv_nsec < 0) { - reltime.tv_nsec += 1000000000; - reltime.tv_sec -= 1; - } - - /* Sleep for the required duration. If woken by a signal, - resume waiting as required by Single Unix Specification. */ - if (reltime.tv_sec < 0 || __libc_nanosleep(&reltime, NULL) == 0) - break; - } - - /* Block the restart signal again */ - sigprocmask(SIG_SETMASK, &initial_mask, NULL); - was_signalled = 0; - } else { - was_signalled = 1; - } - THREAD_SETMEM(self, p_signal_jmp, NULL); - } - - /* Now was_signalled is true if we exited the above code - due to the delivery of a restart signal. In that case, - we know we have been dequeued and resumed and that the - resume count is balanced. Otherwise, there are some - cases to consider. First, try to bump up the resume count - back to zero. If it goes to 1, it means restart() was - invoked on this thread. The signal must be consumed - and the count bumped down and everything is cool. We - can return a 1 to the caller. - Otherwise, no restart was delivered yet, so a potential - race exists; we return a 0 to the caller which must deal - with this race in an appropriate way; for example by - atomically removing the thread from consideration for a - wakeup---if such a thing fails, it means a restart is - being delivered. */ - - if (!was_signalled) { - if (atomic_increment(&self->p_resume_count) != -1) { - __pthread_wait_for_restart_signal(self); - atomic_decrement(&self->p_resume_count); /* should be zero now! */ - /* woke spontaneously and consumed restart signal */ - return 1; - } - /* woke spontaneously but did not consume restart---caller must resolve */ - return 0; - } - /* woken due to restart signal */ - return 1; -} -#endif /* __ASSUME_REALTIME_SIGNALS */ - -void __pthread_restart_new(pthread_descr th) -{ - /* The barrier is proabably not needed, in which case it still documents - our assumptions. The intent is to commit previous writes to shared - memory so the woken thread will have a consistent view. Complementary - read barriers are present to the suspend functions. */ - WRITE_MEMORY_BARRIER(); - kill(th->p_pid, __pthread_sig_restart); -} - -/* There is no __pthread_suspend_new because it would just - be a wasteful wrapper for __pthread_wait_for_restart_signal */ - -int -__pthread_timedsuspend_new(pthread_descr self, const struct timespec *abstime) -{ - sigset_t unblock, initial_mask; - int was_signalled = 0; - sigjmp_buf jmpbuf; - - if (sigsetjmp(jmpbuf, 1) == 0) { - THREAD_SETMEM(self, p_signal_jmp, &jmpbuf); - THREAD_SETMEM(self, p_signal, 0); - /* Unblock the restart signal */ - sigemptyset(&unblock); - sigaddset(&unblock, __pthread_sig_restart); - sigprocmask(SIG_UNBLOCK, &unblock, &initial_mask); - - while (1) { - struct timeval now; - struct timespec reltime; - - /* Compute a time offset relative to now. */ - __gettimeofday (&now, NULL); - reltime.tv_nsec = abstime->tv_nsec - now.tv_usec * 1000; - reltime.tv_sec = abstime->tv_sec - now.tv_sec; - if (reltime.tv_nsec < 0) { - reltime.tv_nsec += 1000000000; - reltime.tv_sec -= 1; - } - - /* Sleep for the required duration. If woken by a signal, - resume waiting as required by Single Unix Specification. */ - if (reltime.tv_sec < 0 || __libc_nanosleep(&reltime, NULL) == 0) - break; - } - - /* Block the restart signal again */ - sigprocmask(SIG_SETMASK, &initial_mask, NULL); - was_signalled = 0; - } else { - was_signalled = 1; - } - THREAD_SETMEM(self, p_signal_jmp, NULL); - - /* Now was_signalled is true if we exited the above code - due to the delivery of a restart signal. In that case, - everything is cool. We have been removed from whatever - we were waiting on by the other thread, and consumed its signal. - - Otherwise we this thread woke up spontaneously, or due to a signal other - than restart. This is an ambiguous case that must be resolved by - the caller; the thread is still eligible for a restart wakeup - so there is a race. */ - - READ_MEMORY_BARRIER(); /* See comment in __pthread_restart_new */ - return was_signalled; -} - - -/* Debugging aid */ - -#ifdef DEBUG -#include <stdarg.h> - -void __pthread_message(char * fmt, ...) -{ - char buffer[1024]; - va_list args; - sprintf(buffer, "%05d : ", __getpid()); - va_start(args, fmt); - vsnprintf(buffer + 8, sizeof(buffer) - 8, fmt, args); - va_end(args); - TEMP_FAILURE_RETRY(__libc_write(2, buffer, strlen(buffer))); -} - -#endif - - -#ifndef SHARED -/* We need a hook to force the cancelation wrappers and file locking - to be linked in when static libpthread is used. */ -extern const int __pthread_provide_wrappers; -static const int *const __pthread_require_wrappers = - &__pthread_provide_wrappers; -extern const int __pthread_provide_lockfile; -static const int *const __pthread_require_lockfile = - &__pthread_provide_lockfile; -#endif |