/* src/threads/thread.cpp - machine independent thread functions Copyright (C) 1996-2011 CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO This file is part of CACAO. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include "config.h" #include #include #include #include "vm/types.h" #include "mm/memory.hpp" #if defined(ENABLE_GC_BOEHM) /* We need to include Boehm's gc.h here for GC_register_my_thread and friends. */ # include "mm/boehm-gc/include/gc.h" #endif #include "native/llni.h" #include "native/native.hpp" #include "threads/lock.hpp" #include "threads/threadlist.hpp" #include "threads/thread.hpp" #include "vm/jit/builtin.hpp" #include "vm/class.hpp" #include "vm/exceptions.hpp" #include "vm/finalizer.hpp" #include "vm/globals.hpp" #include "vm/javaobjects.hpp" #include "vm/method.hpp" #include "vm/options.h" #include "vm/string.hpp" #include "vm/utf8.h" #include "vm/vm.hpp" #if defined(ENABLE_STATISTICS) # include "vm/statistics.h" #endif #include "vm/jit/stacktrace.hpp" /* global variables ***********************************************************/ static methodinfo *thread_method_init; static java_handle_t *threadgroup_system; static java_handle_t *threadgroup_main; #if defined(__LINUX__) /* XXX Remove for exact-GC. */ bool threads_pthreads_implementation_nptl; #endif /* static functions ***********************************************************/ static void thread_create_initial_thread(void); static threadobject *thread_new(int32_t flags); /* threads_preinit ************************************************************* Do some early initialization of stuff required. *******************************************************************************/ void threads_preinit(void) { threadobject *mainthread; #if defined(__LINUX__) && defined(_CS_GNU_LIBPTHREAD_VERSION) char *pathbuf; size_t len; #endif TRACESUBSYSTEMINITIALIZATION("threads_preinit"); #if defined(__LINUX__) /* XXX Remove for exact-GC. */ /* On Linux we need to check the pthread implementation. */ /* _CS_GNU_LIBPTHREAD_VERSION (GNU C library only; since glibc 2.3.2) */ /* If the glibc is a pre-2.3.2 version, we fall back to linuxthreads. */ # if defined(_CS_GNU_LIBPTHREAD_VERSION) len = confstr(_CS_GNU_LIBPTHREAD_VERSION, NULL, (size_t) 0); /* Some systems return as length 0 (maybe cross-compilation related). In this case we also fall back to linuxthreads. */ if (len > 0) { pathbuf = MNEW(char, len); (void) confstr(_CS_GNU_LIBPTHREAD_VERSION, pathbuf, len); if (strstr(pathbuf, "NPTL") != NULL) threads_pthreads_implementation_nptl = true; else threads_pthreads_implementation_nptl = false; } else threads_pthreads_implementation_nptl = false; # else threads_pthreads_implementation_nptl = false; # endif #endif /* Initialize the threads implementation (sets the thinlock on the main thread). */ threads_impl_preinit(); /* Create internal thread data-structure for the main thread. */ mainthread = thread_new(THREAD_FLAG_JAVA); /* Add the thread to the thread list. */ ThreadList::add_to_active_thread_list(mainthread); /* The main thread should always have index 1. */ if (mainthread->index != 1) vm_abort("threads_preinit: main thread index not 1: %d != 1", mainthread->index); /* Thread is already running. */ mainthread->state = THREAD_STATE_RUNNABLE; /* Store the internal thread data-structure in the TSD. */ thread_set_current(mainthread); } /* threads_init **************************************************************** Initialize the main thread. *******************************************************************************/ void threads_init(void) { TRACESUBSYSTEMINITIALIZATION("threads_init"); /* Create the system and main thread groups. */ ThreadRuntime::thread_create_initial_threadgroups(&threadgroup_main, &threadgroup_system); /* Cache the java.lang.Thread initialization method. */ thread_method_init = ThreadRuntime::get_thread_init_method(); if (thread_method_init == NULL) vm_abort("threads_init: failed to resolve thread init method"); thread_create_initial_thread(); } /* thread_create_object ******************************************************** Create a Java thread object for the given thread data-structure, initializes it and adds the thread to the threadgroup. ARGUMENTS: t ....... thread name .... thread name group ... threadgroup RETURN: *******************************************************************************/ static bool thread_create_object(threadobject *t, java_handle_t *name, java_handle_t *group) { /* Create a java.lang.Thread Java object. */ java_handle_t* h = builtin_new(class_java_lang_Thread); if (h == NULL) return false; java_lang_Thread jlt(h); // Set the Java object in the thread data-structure. This // indicates that the thread is attached to the VM. t->object = LLNI_DIRECT(jlt.get_handle()); return ThreadRuntime::invoke_thread_initializer(jlt, t, thread_method_init, name, group); } /* thread_create_initial_thread *********************************************** Create the initial thread: main *******************************************************************************/ static void thread_create_initial_thread(void) { threadobject *t; java_handle_t *name; /* Get the main-thread (NOTE: The main thread is always the first thread in the list). */ t = ThreadList::get_main_thread(); /* The thread name. */ name = javastring_new(utf_main); #if defined(ENABLE_INTRP) /* create interpreter stack */ if (opt_intrp) { MSET(intrp_main_stack, 0, u1, opt_stacksize); mainthread->_global_sp = (Cell*) (intrp_main_stack + opt_stacksize); } #endif /* Create the Java thread object. */ if (!thread_create_object(t, name, threadgroup_main)) vm_abort("thread_create_initial_thread: failed to create Java object"); /* Initialize the implementation specific bits. */ threads_impl_init(); DEBUGTHREADS("starting (main)", t); } /* thread_new ****************************************************************** Allocates and initializes an internal thread data-structure and adds it to the threads list. *******************************************************************************/ static threadobject *thread_new(int32_t flags) { int32_t index; threadobject *t; /* Lock the thread lists */ ThreadList::lock(); index = ThreadList::get_free_thread_index(); /* Allocate a thread data structure. */ /* First, try to get one from the free-list. */ t = ThreadList::get_free_thread(); /* Unlock the thread lists. */ ThreadList::unlock(); if (t != NULL) { /* Equivalent of MZERO on the else path */ threads_impl_thread_clear(t); } else { #if defined(ENABLE_GC_BOEHM) t = GCNEW_UNCOLLECTABLE(threadobject, 1); #else t = NEW(threadobject); #endif #if defined(ENABLE_STATISTICS) if (opt_stat) size_threadobject += sizeof(threadobject); #endif /* Clear memory. */ MZERO(t, threadobject, 1); // Initialize the mutex and the condition. t->flc_lock = new Mutex(); t->flc_cond = new Condition(); t->waitmutex = new Mutex(); t->waitcond = new Condition(); t->suspendmutex = new Mutex(); t->suspendcond = new Condition(); #if defined(ENABLE_TLH) tlh_init(&(t->tlh)); #endif #if defined(ENABLE_GC_CACAO) /* Register reference to java.lang.Thread with the GC. */ /* FIXME is it ok to do this only once? */ gc_reference_register(&(t->object), GC_REFTYPE_THREADOBJECT); gc_reference_register(&(t->_exceptionptr), GC_REFTYPE_THREADOBJECT); #endif t->_dumpmemory = new DumpMemory(); } /* Pre-compute the thinlock-word. */ assert(index != 0); t->index = index; t->thinlock = Lockword::pre_compute_thinlock(t->index); t->flags = flags; t->state = THREAD_STATE_NEW; #if defined(ENABLE_GC_CACAO) t->flags |= THREAD_FLAG_IN_NATIVE; #endif /* Initialize the implementation-specific bits. */ threads_impl_thread_reuse(t); return t; } /* thread_free ***************************************************************** Remove the thread from the threads-list and free the internal thread data structure. The thread index is added to the thread-index free-list. IN: t ... thread data structure *******************************************************************************/ void thread_free(threadobject *t) { java_handle_t *h = LLNI_WRAP(t->object); java_lang_Thread jlt(h); ThreadRuntime::clear_heap_reference(jlt); /* Set the reference to the Java object to NULL. */ t->object = 0; ThreadList::deactivate_thread(t); } /* threads_thread_start_internal *********************************************** Start an internal thread in the JVM. No Java thread objects exists so far. IN: name.......UTF-8 name of the thread f..........function pointer to C function to start *******************************************************************************/ static void thread_cleanup_finalizer(java_handle_t *h, void *data) { threadobject *t = reinterpret_cast(data); ThreadList::release_thread(t, false); } bool threads_thread_start_internal(utf *name, functionptr f) { threadobject *t; /* Create internal thread data-structure. */ t = thread_new(THREAD_FLAG_INTERNAL | THREAD_FLAG_DAEMON); /* Add the thread to the thread list. */ ThreadList::add_to_active_thread_list(t); /* Create the Java thread object. */ if (!thread_create_object(t, javastring_new(name), threadgroup_system)) { ThreadList::release_thread(t, true); return false; } #if defined(ENABLE_GC_BOEHM) Finalizer::attach_custom_finalizer(LLNI_WRAP(t->object), thread_cleanup_finalizer, t); #endif /* Start the thread. */ threads_impl_thread_start(t, f); /* everything's ok */ return true; } /* threads_thread_start ******************************************************** Start a Java thread in the JVM. Only the java thread object exists so far. IN: object.....the java thread object java.lang.Thread *******************************************************************************/ void threads_thread_start(java_handle_t *object) { java_lang_Thread jlt(object); /* Create internal thread data-structure. */ u4 flags = THREAD_FLAG_JAVA; #if defined(ENABLE_JAVASE) /* Is this a daemon thread? */ if (jlt.get_daemon()) flags |= THREAD_FLAG_DAEMON; #endif threadobject* t = thread_new(flags); /* Link the two objects together. */ t->object = LLNI_DIRECT(object); /* Add the thread to the thread list. */ ThreadList::add_to_active_thread_list(t); Atomic::write_memory_barrier(); ThreadRuntime::setup_thread_vmdata(jlt, t); #if defined(ENABLE_GC_BOEHM) Finalizer::attach_custom_finalizer(LLNI_WRAP(t->object), thread_cleanup_finalizer, t); #endif thread_set_state_runnable(t); /* Start the thread. Don't pass a function pointer (NULL) since we want Thread.run()V here. */ threads_impl_thread_start(t, NULL); } /** * Attaches the current thread to the VM. * * @param vm_aargs Attach arguments. * @param isdaemon true if the attached thread should be a daemon * thread. * * @return true on success, false otherwise. */ bool thread_attach_current_thread(JavaVMAttachArgs *vm_aargs, bool isdaemon) { bool result; threadobject *t; utf *u; java_handle_t *name; java_handle_t *group; /* If the current thread has already been attached, this operation is a no-op. */ result = thread_current_is_attached(); if (result == true) return true; /* Create internal thread data structure. */ u4 flags = THREAD_FLAG_JAVA; if (isdaemon) flags |= THREAD_FLAG_DAEMON; t = thread_new(flags); /* Store the internal thread data-structure in the TSD. */ thread_set_current(t); /* The thread is flagged and (non-)daemon thread, we can leave the mutex. */ /* Add the thread to the thread list. */ ThreadList::add_to_active_thread_list(t); DEBUGTHREADS("attaching", t); /* Get the thread name. */ if (vm_aargs != NULL) { u = utf_new_char(vm_aargs->name); } else { u = utf_null; } name = javastring_new(u); #if defined(ENABLE_JAVASE) /* Get the threadgroup. */ if (vm_aargs != NULL) group = (java_handle_t *) vm_aargs->group; else group = NULL; /* If no threadgroup was given, use the main threadgroup. */ if (group == NULL) group = threadgroup_main; #endif #if defined(ENABLE_INTRP) /* create interpreter stack */ if (opt_intrp) { MSET(intrp_main_stack, 0, u1, opt_stacksize); thread->_global_sp = (Cell *) (intrp_main_stack + opt_stacksize); } #endif /* Create the Java thread object. */ if (!thread_create_object(t, name, group)) { ThreadList::release_thread(t, true); return false; } /* The thread is completely initialized. */ thread_set_state_runnable(t); return true; } /** * Attaches the current external thread to the VM. This function is * called by JNI's AttachCurrentThread. * * @param vm_aargs Attach arguments. * @param isdaemon true if the attached thread should be a daemon * thread. * * @return true on success, false otherwise. */ bool thread_attach_current_external_thread(JavaVMAttachArgs *vm_aargs, bool isdaemon) { int result; #if defined(ENABLE_GC_BOEHM) struct GC_stack_base sb; /* Register the thread with Boehm-GC. This must happen before the thread allocates any memory from the GC heap.*/ result = GC_get_stack_base(&sb); if (result != GC_SUCCESS) vm_abort("threads_attach_current_thread: GC_get_stack_base failed"); GC_register_my_thread(&sb); #endif result = thread_attach_current_thread(vm_aargs, isdaemon); if (result == false) { #if defined(ENABLE_GC_BOEHM) /* Unregister the thread. */ GC_unregister_my_thread(); #endif return false; } return true; } /** * Detaches the current external thread from the VM. This function is * called by JNI's DetachCurrentThread. * * @return true on success, false otherwise. */ bool thread_detach_current_external_thread(void) { int result; result = thread_detach_current_thread(); if (result == false) return false; #if defined(ENABLE_GC_BOEHM) /* Unregister the thread with Boehm-GC. This must happen after the thread allocates any memory from the GC heap. */ /* Don't detach the main thread. This is a workaround for OpenJDK's java launcher. */ if (thread_get_current()->index != 1) GC_unregister_my_thread(); #endif return true; } /* thread_fprint_name ********************************************************** Print the name of the given thread to the given stream. ARGUMENTS: t ........ thread data-structure stream ... stream to print to *******************************************************************************/ void thread_fprint_name(threadobject *t, FILE *stream) { if (LLNI_WRAP(t->object) == NULL) vm_abort(""); java_lang_Thread jlt(LLNI_WRAP(t->object)); ThreadRuntime::print_thread_name(jlt, stream); } /* thread_print_info *********************************************************** Print information of the passed thread. ARGUMENTS: t ... thread data-structure. *******************************************************************************/ void thread_print_info(threadobject *t) { java_lang_Thread jlt(LLNI_WRAP(t->object)); /* Print as much as we can when we are in state NEW. */ if (jlt.get_handle() != NULL) { /* Print thread name. */ printf("\""); thread_fprint_name(t, stdout); printf("\""); } else { } if (thread_is_daemon(t)) printf(" daemon"); if (jlt.get_handle() != NULL) { printf(" prio=%d", jlt.get_priority()); } #if SIZEOF_VOID_P == 8 printf(" t=0x%016lx tid=0x%016lx (%ld)", (ptrint) t, (ptrint) t->tid, (ptrint) t->tid); #else printf(" t=0x%08x tid=0x%08x (%d)", (ptrint) t, (ptrint) t->tid, (ptrint) t->tid); #endif printf(" index=%d", t->index); /* Print thread state. */ int state = cacaothread_get_state(t); switch (state) { case THREAD_STATE_NEW: printf(" new"); break; case THREAD_STATE_RUNNABLE: printf(" runnable"); break; case THREAD_STATE_BLOCKED: printf(" blocked"); break; case THREAD_STATE_WAITING: printf(" waiting"); break; case THREAD_STATE_TIMED_WAITING: printf(" waiting on condition"); break; case THREAD_STATE_PARKED: printf(" parked"); break; case THREAD_STATE_TIMED_PARKED: printf(" timed parked"); break; case THREAD_STATE_TERMINATED: printf(" terminated"); break; default: vm_abort("thread_print_info: unknown thread state %d", state); } } /* threads_get_current_tid ***************************************************** Return the tid of the current thread. RETURN VALUE: the current tid *******************************************************************************/ intptr_t threads_get_current_tid(void) { threadobject *thread; thread = THREADOBJECT; /* this may happen during bootstrap */ if (thread == NULL) return 0; return (intptr_t) thread->tid; } /** * Set the current state of the given thread. This method should only * be called while holding the threadlist-lock and after checking that * the new state is valid. It is best to not call this method directly * but call the specific setter methods below. */ static inline void thread_set_state(threadobject *t, int state) { // Set the state of our internal threadobject. t->state = state; ThreadRuntime::set_javathread_state(t, state); } /* thread_set_state_runnable *************************************************** Set the current state of the given thread to THREAD_STATE_RUNNABLE. NOTE: If the thread has already terminated, don't set the state. This is important for threads_detach_thread. *******************************************************************************/ void thread_set_state_runnable(threadobject *t) { if (t->state != THREAD_STATE_TERMINATED) { thread_set_state(t, THREAD_STATE_RUNNABLE); DEBUGTHREADS("is RUNNABLE", t); } } /* thread_set_state_waiting **************************************************** Set the current state of the given thread to THREAD_STATE_WAITING. NOTE: If the thread has already terminated, don't set the state. This is important for threads_detach_thread. *******************************************************************************/ void thread_set_state_waiting(threadobject *t) { if (t->state != THREAD_STATE_TERMINATED) { thread_set_state(t, THREAD_STATE_WAITING); DEBUGTHREADS("is WAITING", t); } } /* thread_set_state_timed_waiting ********************************************** Set the current state of the given thread to THREAD_STATE_TIMED_WAITING. NOTE: If the thread has already terminated, don't set the state. This is important for threads_detach_thread. *******************************************************************************/ void thread_set_state_timed_waiting(threadobject *t) { if (t->state != THREAD_STATE_TERMINATED) { thread_set_state(t, THREAD_STATE_TIMED_WAITING); DEBUGTHREADS("is TIMED_WAITING", t); } } /* thread_set_state_parked ***************************************************** Set the current state of the given thread to THREAD_STATE_PARKED. NOTE: If the thread has already terminated, don't set the state. This is important for threads_detach_thread. *******************************************************************************/ void thread_set_state_parked(threadobject *t) { if (t->state != THREAD_STATE_TERMINATED) { thread_set_state(t, THREAD_STATE_PARKED); DEBUGTHREADS("is PARKED", t); } } /* thread_set_state_timed_parked *********************************************** Set the current state of the given thread to THREAD_STATE_TIMED_PARKED. NOTE: If the thread has already terminated, don't set the state. This is important for threads_detach_thread. *******************************************************************************/ void thread_set_state_timed_parked(threadobject *t) { if (t->state != THREAD_STATE_TERMINATED) { thread_set_state(t, THREAD_STATE_TIMED_PARKED); DEBUGTHREADS("is TIMED_PARKED", t); } } /* thread_set_state_terminated ************************************************* Set the current state of the given thread to THREAD_STATE_TERMINATED. *******************************************************************************/ void thread_set_state_terminated(threadobject *t) { /* Set the state inside a lock. */ thread_set_state(t, THREAD_STATE_TERMINATED); DEBUGTHREADS("is TERMINATED", t); } /* thread_get_thread ********************************************************** Return the thread data structure of the given Java thread object. ARGUMENTS: h ... java.lang.{VM}Thread object RETURN VALUE: the thread object NOTE: Usage of this function without the thread list lock held is almost certainly a bug. *******************************************************************************/ threadobject *thread_get_thread(java_handle_t *h) { return ThreadRuntime::get_threadobject_from_thread(h); } /* threads_thread_is_alive ***************************************************** Returns if the give thread is alive. *******************************************************************************/ bool threads_thread_is_alive(threadobject *t) { int state; state = cacaothread_get_state(t); switch (state) { case THREAD_STATE_NEW: case THREAD_STATE_TERMINATED: return false; case THREAD_STATE_RUNNABLE: case THREAD_STATE_BLOCKED: case THREAD_STATE_WAITING: case THREAD_STATE_TIMED_WAITING: case THREAD_STATE_PARKED: case THREAD_STATE_TIMED_PARKED: return true; default: vm_abort("threads_thread_is_alive: unknown thread state %d", state); } /* keep compiler happy */ return false; } /* thread_is_interrupted ******************************************************* Check if the given thread has been interrupted. ARGUMENTS: t ... the thread to check RETURN VALUE: true, if the given thread had been interrupted *******************************************************************************/ bool thread_is_interrupted(threadobject *t) { /* We need the mutex because classpath will call this function when a blocking system call is interrupted. The mutex ensures that it will see the correct value for the interrupted flag. */ t->waitmutex->lock(); bool interrupted = t->interrupted; t->waitmutex->unlock(); return interrupted; } /* thread_set_interrupted ****************************************************** Set the interrupted flag to the given value. ARGUMENTS: interrupted ... value to set *******************************************************************************/ void thread_set_interrupted(threadobject *t, bool interrupted) { t->waitmutex->lock(); t->interrupted = interrupted; t->waitmutex->unlock(); } /* thread_handle_set_priority ************************************************** Calls threads_set_thread_priority for the threadobject associated with the thread indicated by handle th, while holding the thread list lock. *******************************************************************************/ void thread_handle_set_priority(java_handle_t *th, int priority) { threadobject *t = thread_get_thread(th); /* For GNU classpath, this should not happen, because both setPriority() and start() are synchronized. */ assert(t != 0); threads_set_thread_priority(t->tid, priority); } /* thread_handle_is_interrupted ************************************************ Calls thread_is_interrupted for the threadobject associated with the thread indicated by handle th, while holding the thread list lock. *******************************************************************************/ bool thread_handle_is_interrupted(java_handle_t *th) { threadobject *t = thread_get_thread(th); return t ? thread_is_interrupted(t) : false; } /* thread_handle_interrupt ***************************************************** Calls threads_thread_interrupt for the threadobject associated with the thread indicated by handle th, while holding the thread list lock. *******************************************************************************/ void thread_handle_interrupt(java_handle_t *th) { threadobject *t = thread_get_thread(th); /* For GNU classpath, this should not happen, because both interrupt() and start() are synchronized. */ assert(t != 0); threads_thread_interrupt(t); } /* thread_handle_get_state ***************************************************** Calls cacaothread_get_state for the threadobject associated with the thread indicated by handle th, while holding the thread list lock. *******************************************************************************/ int thread_handle_get_state(java_handle_t *th) { threadobject *t = thread_get_thread(th); return t ? cacaothread_get_state(t) : THREAD_STATE_NEW; } /* * These are local overrides for various environment variables in Emacs. * Please do not remove this and leave it at the end of the file, where * Emacs will automagically detect them. * --------------------------------------------------------------------- * Local variables: * mode: c++ * indent-tabs-mode: t * c-basic-offset: 4 * tab-width: 4 * End: * vim:noexpandtab:sw=4:ts=4: */