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nest-open-source / nest-learning-thermostat / 5.1.5 / nspr / refs/heads/master / . / nspr-4.8.6 / mozilla / nsprpub / pr / src / threads / combined / pruthr.c
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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Netscape Portable Runtime (NSPR).
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998-2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "primpl.h"
#include <signal.h>
#include <string.h>
#if defined(WIN95)
/*
** Some local variables report warnings on Win95 because the code paths
** using them are conditioned on HAVE_CUSTOME_USER_THREADS.
** The pragma suppresses the warning.
**
*/
#pragma warning(disable : 4101)
#endif
/* _pr_activeLock protects the following global variables */
PRLock *_pr_activeLock;
PRInt32 _pr_primordialExitCount; /* In PR_Cleanup(), the primordial thread
* waits until all other user (non-system)
* threads have terminated before it exits.
* So whenever we decrement _pr_userActive,
* it is compared with
* _pr_primordialExitCount.
* If the primordial thread is a system
* thread, then _pr_primordialExitCount
* is 0. If the primordial thread is
* itself a user thread, then
* _pr_primordialThread is 1.
*/
PRCondVar *_pr_primordialExitCVar; /* When _pr_userActive is decremented to
* _pr_primordialExitCount, this condition
* variable is notified.
*/
PRLock *_pr_deadQLock;
PRUint32 _pr_numNativeDead;
PRUint32 _pr_numUserDead;
PRCList _pr_deadNativeQ;
PRCList _pr_deadUserQ;
PRUint32 _pr_join_counter;
PRUint32 _pr_local_threads;
PRUint32 _pr_global_threads;
PRBool suspendAllOn = PR_FALSE;
PRThread *suspendAllThread = NULL;
extern PRCList _pr_active_global_threadQ;
extern PRCList _pr_active_local_threadQ;
static void _PR_DecrActiveThreadCount(PRThread *thread);
static PRThread *_PR_AttachThread(PRThreadType, PRThreadPriority, PRThreadStack *);
static void _PR_InitializeNativeStack(PRThreadStack *ts);
static void _PR_InitializeRecycledThread(PRThread *thread);
static void _PR_UserRunThread(void);
void _PR_InitThreads(PRThreadType type, PRThreadPriority priority,
PRUintn maxPTDs)
{
PRThread *thread;
PRThreadStack *stack;
_pr_terminationCVLock = PR_NewLock();
_pr_activeLock = PR_NewLock();
#ifndef HAVE_CUSTOM_USER_THREADS
stack = PR_NEWZAP(PRThreadStack);
#ifdef HAVE_STACK_GROWING_UP
stack->stackTop = (char*) ((((long)&type) >> _pr_pageShift)
<< _pr_pageShift);
#else
#if defined(SOLARIS) || defined (UNIXWARE) && defined (USR_SVR4_THREADS)
stack->stackTop = (char*) &thread;
#else
stack->stackTop = (char*) ((((long)&type + _pr_pageSize - 1)
>> _pr_pageShift) << _pr_pageShift);
#endif
#endif
#else
/* If stack is NULL, we're using custom user threads like NT fibers. */
stack = PR_NEWZAP(PRThreadStack);
if (stack) {
stack->stackSize = 0;
_PR_InitializeNativeStack(stack);
}
#endif /* HAVE_CUSTOM_USER_THREADS */
thread = _PR_AttachThread(type, priority, stack);
if (thread) {
_PR_MD_SET_CURRENT_THREAD(thread);
if (type == PR_SYSTEM_THREAD) {
thread->flags = _PR_SYSTEM;
_pr_systemActive++;
_pr_primordialExitCount = 0;
} else {
_pr_userActive++;
_pr_primordialExitCount = 1;
}
thread->no_sched = 1;
_pr_primordialExitCVar = PR_NewCondVar(_pr_activeLock);
}
if (!thread) PR_Abort();
#ifdef _PR_LOCAL_THREADS_ONLY
thread->flags |= _PR_PRIMORDIAL;
#else
thread->flags |= _PR_PRIMORDIAL | _PR_GLOBAL_SCOPE;
#endif
/*
* Needs _PR_PRIMORDIAL flag set before calling
* _PR_MD_INIT_THREAD()
*/
if (_PR_MD_INIT_THREAD(thread) == PR_FAILURE) {
/*
* XXX do what?
*/
}
if (_PR_IS_NATIVE_THREAD(thread)) {
PR_APPEND_LINK(&thread->active, &_PR_ACTIVE_GLOBAL_THREADQ());
_pr_global_threads++;
} else {
PR_APPEND_LINK(&thread->active, &_PR_ACTIVE_LOCAL_THREADQ());
_pr_local_threads++;
}
_pr_recycleThreads = 0;
_pr_deadQLock = PR_NewLock();
_pr_numNativeDead = 0;
_pr_numUserDead = 0;
PR_INIT_CLIST(&_pr_deadNativeQ);
PR_INIT_CLIST(&_pr_deadUserQ);
}
void _PR_CleanupThreads(void)
{
if (_pr_terminationCVLock) {
PR_DestroyLock(_pr_terminationCVLock);
_pr_terminationCVLock = NULL;
}
if (_pr_activeLock) {
PR_DestroyLock(_pr_activeLock);
_pr_activeLock = NULL;
}
if (_pr_primordialExitCVar) {
PR_DestroyCondVar(_pr_primordialExitCVar);
_pr_primordialExitCVar = NULL;
}
/* TODO _pr_dead{Native,User}Q need to be deleted */
if (_pr_deadQLock) {
PR_DestroyLock(_pr_deadQLock);
_pr_deadQLock = NULL;
}
}
/*
** Initialize a stack for a native thread
*/
static void _PR_InitializeNativeStack(PRThreadStack *ts)
{
if( ts && (ts->stackTop == 0) ) {
ts->allocSize = ts->stackSize;
/*
** Setup stackTop and stackBottom values.
*/
#ifdef HAVE_STACK_GROWING_UP
ts->allocBase = (char*) ((((long)&ts) >> _pr_pageShift)
<< _pr_pageShift);
ts->stackBottom = ts->allocBase + ts->stackSize;
ts->stackTop = ts->allocBase;
#else
ts->allocBase = (char*) ((((long)&ts + _pr_pageSize - 1)
>> _pr_pageShift) << _pr_pageShift);
ts->stackTop = ts->allocBase;
ts->stackBottom = ts->allocBase - ts->stackSize;
#endif
}
}
void _PR_NotifyJoinWaiters(PRThread *thread)
{
/*
** Handle joinable threads. Change the state to waiting for join.
** Remove from our run Q and put it on global waiting to join Q.
** Notify on our "termination" condition variable so that joining
** thread will know about our termination. Switch our context and
** come back later on to continue the cleanup.
*/
PR_ASSERT(thread == _PR_MD_CURRENT_THREAD());
if (thread->term != NULL) {
PR_Lock(_pr_terminationCVLock);
_PR_THREAD_LOCK(thread);
thread->state = _PR_JOIN_WAIT;
if ( !_PR_IS_NATIVE_THREAD(thread) ) {
_PR_MISCQ_LOCK(thread->cpu);
_PR_ADD_JOINQ(thread, thread->cpu);
_PR_MISCQ_UNLOCK(thread->cpu);
}
_PR_THREAD_UNLOCK(thread);
PR_NotifyCondVar(thread->term);
PR_Unlock(_pr_terminationCVLock);
_PR_MD_WAIT(thread, PR_INTERVAL_NO_TIMEOUT);
PR_ASSERT(thread->state != _PR_JOIN_WAIT);
}
}
/*
* Zero some of the data members of a recycled thread.
*
* Note that we can do this either when a dead thread is added to
* the dead thread queue or when it is reused. Here, we are doing
* this lazily, when the thread is reused in _PR_CreateThread().
*/
static void _PR_InitializeRecycledThread(PRThread *thread)
{
/*
* Assert that the following data members are already zeroed
* by _PR_CleanupThread().
*/
#ifdef DEBUG
if (thread->privateData) {
unsigned int i;
for (i = 0; i < thread->tpdLength; i++) {
PR_ASSERT(thread->privateData[i] == NULL);
}
}
#endif
PR_ASSERT(thread->dumpArg == 0 && thread->dump == 0);
PR_ASSERT(thread->errorString == 0 && thread->errorStringSize == 0);
PR_ASSERT(thread->errorStringLength == 0);
/* Reset data members in thread structure */
thread->errorCode = thread->osErrorCode = 0;
thread->io_pending = thread->io_suspended = PR_FALSE;
thread->environment = 0;
PR_INIT_CLIST(&thread->lockList);
}
PRStatus _PR_RecycleThread(PRThread *thread)
{
if ( _PR_IS_NATIVE_THREAD(thread) &&
_PR_NUM_DEADNATIVE < _pr_recycleThreads) {
_PR_DEADQ_LOCK;
PR_APPEND_LINK(&thread->links, &_PR_DEADNATIVEQ);
_PR_INC_DEADNATIVE;
_PR_DEADQ_UNLOCK;
return (PR_SUCCESS);
} else if ( !_PR_IS_NATIVE_THREAD(thread) &&
_PR_NUM_DEADUSER < _pr_recycleThreads) {
_PR_DEADQ_LOCK;
PR_APPEND_LINK(&thread->links, &_PR_DEADUSERQ);
_PR_INC_DEADUSER;
_PR_DEADQ_UNLOCK;
return (PR_SUCCESS);
}
return (PR_FAILURE);
}
/*
* Decrement the active thread count, either _pr_systemActive or
* _pr_userActive, depending on whether the thread is a system thread
* or a user thread. If all the user threads, except possibly
* the primordial thread, have terminated, we notify the primordial
* thread of this condition.
*
* Since this function will lock _pr_activeLock, do not call this
* function while holding the _pr_activeLock lock, as this will result
* in a deadlock.
*/
static void
_PR_DecrActiveThreadCount(PRThread *thread)
{
PR_Lock(_pr_activeLock);
if (thread->flags & _PR_SYSTEM) {
_pr_systemActive--;
} else {
_pr_userActive--;
if (_pr_userActive == _pr_primordialExitCount) {
PR_NotifyCondVar(_pr_primordialExitCVar);
}
}
PR_Unlock(_pr_activeLock);
}
/*
** Detach thread structure
*/
static void
_PR_DestroyThread(PRThread *thread)
{
_PR_MD_FREE_LOCK(&thread->threadLock);
PR_DELETE(thread);
}
void
_PR_NativeDestroyThread(PRThread *thread)
{
if(thread->term) {
PR_DestroyCondVar(thread->term);
thread->term = 0;
}
if (NULL != thread->privateData) {
PR_ASSERT(0 != thread->tpdLength);
PR_DELETE(thread->privateData);
thread->tpdLength = 0;
}
PR_DELETE(thread->stack);
_PR_DestroyThread(thread);
}
void
_PR_UserDestroyThread(PRThread *thread)
{
if(thread->term) {
PR_DestroyCondVar(thread->term);
thread->term = 0;
}
if (NULL != thread->privateData) {
PR_ASSERT(0 != thread->tpdLength);
PR_DELETE(thread->privateData);
thread->tpdLength = 0;
}
_PR_MD_FREE_LOCK(&thread->threadLock);
if (thread->threadAllocatedOnStack == 1) {
_PR_MD_CLEAN_THREAD(thread);
/*
* Because the no_sched field is set, this thread/stack will
* will not be re-used until the flag is cleared by the thread
* we will context switch to.
*/
_PR_FreeStack(thread->stack);
} else {
#ifdef WINNT
_PR_MD_CLEAN_THREAD(thread);
#else
/*
* This assertion does not apply to NT. On NT, every fiber
* has its threadAllocatedOnStack equal to 0. Elsewhere,
* only the primordial thread has its threadAllocatedOnStack
* equal to 0.
*/
PR_ASSERT(thread->flags & _PR_PRIMORDIAL);
#endif
}
}
/*
** Run a thread's start function. When the start function returns the
** thread is done executing and no longer needs the CPU. If there are no
** more user threads running then we can exit the program.
*/
void _PR_NativeRunThread(void *arg)
{
PRThread *thread = (PRThread *)arg;
_PR_MD_SET_CURRENT_THREAD(thread);
_PR_MD_SET_CURRENT_CPU(NULL);
/* Set up the thread stack information */
_PR_InitializeNativeStack(thread->stack);
/* Set up the thread md information */
if (_PR_MD_INIT_THREAD(thread) == PR_FAILURE) {
/*
* thread failed to initialize itself, possibly due to
* failure to allocate per-thread resources
*/
return;
}
while(1) {
thread->state = _PR_RUNNING;
/*
* Add to list of active threads
*/
PR_Lock(_pr_activeLock);
PR_APPEND_LINK(&thread->active, &_PR_ACTIVE_GLOBAL_THREADQ());
_pr_global_threads++;
PR_Unlock(_pr_activeLock);
(*thread->startFunc)(thread->arg);
/*
* The following two assertions are meant for NT asynch io.
*
* The thread should have no asynch io in progress when it
* exits, otherwise the overlapped buffer, which is part of
* the thread structure, would become invalid.
*/
PR_ASSERT(thread->io_pending == PR_FALSE);
/*
* This assertion enforces the programming guideline that
* if an io function times out or is interrupted, the thread
* should close the fd to force the asynch io to abort
* before it exits. Right now, closing the fd is the only
* way to clear the io_suspended flag.
*/
PR_ASSERT(thread->io_suspended == PR_FALSE);
/*
* remove thread from list of active threads
*/
PR_Lock(_pr_activeLock);
PR_REMOVE_LINK(&thread->active);
_pr_global_threads--;
PR_Unlock(_pr_activeLock);
PR_LOG(_pr_thread_lm, PR_LOG_MIN, ("thread exiting"));
/* All done, time to go away */
_PR_CleanupThread(thread);
_PR_NotifyJoinWaiters(thread);
_PR_DecrActiveThreadCount(thread);
thread->state = _PR_DEAD_STATE;
if (!_pr_recycleThreads || (_PR_RecycleThread(thread) ==
PR_FAILURE)) {
/*
* thread not recycled
* platform-specific thread exit processing
* - for stuff like releasing native-thread resources, etc.
*/
_PR_MD_EXIT_THREAD(thread);
/*
* Free memory allocated for the thread
*/
_PR_NativeDestroyThread(thread);
/*
* thread gone, cannot de-reference thread now
*/
return;
}
/* Now wait for someone to activate us again... */
_PR_MD_WAIT(thread, PR_INTERVAL_NO_TIMEOUT);
}
}
static void _PR_UserRunThread(void)
{
PRThread *thread = _PR_MD_CURRENT_THREAD();
PRIntn is;
if (_MD_LAST_THREAD())
_MD_LAST_THREAD()->no_sched = 0;
#ifdef HAVE_CUSTOM_USER_THREADS
if (thread->stack == NULL) {
thread->stack = PR_NEWZAP(PRThreadStack);
_PR_InitializeNativeStack(thread->stack);
}
#endif /* HAVE_CUSTOM_USER_THREADS */
while(1) {
/* Run thread main */
if ( !_PR_IS_NATIVE_THREAD(thread)) _PR_MD_SET_INTSOFF(0);
/*
* Add to list of active threads
*/
if (!(thread->flags & _PR_IDLE_THREAD)) {
PR_Lock(_pr_activeLock);
PR_APPEND_LINK(&thread->active, &_PR_ACTIVE_LOCAL_THREADQ());
_pr_local_threads++;
PR_Unlock(_pr_activeLock);
}
(*thread->startFunc)(thread->arg);
/*
* The following two assertions are meant for NT asynch io.
*
* The thread should have no asynch io in progress when it
* exits, otherwise the overlapped buffer, which is part of
* the thread structure, would become invalid.
*/
PR_ASSERT(thread->io_pending == PR_FALSE);
/*
* This assertion enforces the programming guideline that
* if an io function times out or is interrupted, the thread
* should close the fd to force the asynch io to abort
* before it exits. Right now, closing the fd is the only
* way to clear the io_suspended flag.
*/
PR_ASSERT(thread->io_suspended == PR_FALSE);
PR_Lock(_pr_activeLock);
/*
* remove thread from list of active threads
*/
if (!(thread->flags & _PR_IDLE_THREAD)) {
PR_REMOVE_LINK(&thread->active);
_pr_local_threads--;
}
PR_Unlock(_pr_activeLock);
PR_LOG(_pr_thread_lm, PR_LOG_MIN, ("thread exiting"));
/* All done, time to go away */
_PR_CleanupThread(thread);
_PR_INTSOFF(is);
_PR_NotifyJoinWaiters(thread);
_PR_DecrActiveThreadCount(thread);
thread->state = _PR_DEAD_STATE;
if (!_pr_recycleThreads || (_PR_RecycleThread(thread) ==
PR_FAILURE)) {
/*
** Destroy the thread resources
*/
_PR_UserDestroyThread(thread);
}
/*
** Find another user thread to run. This cpu has finished the
** previous threads main and is now ready to run another thread.
*/
{
PRInt32 is;
_PR_INTSOFF(is);
_PR_MD_SWITCH_CONTEXT(thread);
}
/* Will land here when we get scheduled again if we are recycling... */
}
}
void _PR_SetThreadPriority(PRThread *thread, PRThreadPriority newPri)
{
PRThread *me = _PR_MD_CURRENT_THREAD();
PRIntn is;
if ( _PR_IS_NATIVE_THREAD(thread) ) {
_PR_MD_SET_PRIORITY(&(thread->md), newPri);
return;
}
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSOFF(is);
_PR_THREAD_LOCK(thread);
if (newPri != thread->priority) {
_PRCPU *cpu = thread->cpu;
switch (thread->state) {
case _PR_RUNNING:
/* Change my priority */
_PR_RUNQ_LOCK(cpu);
thread->priority = newPri;
if (_PR_RUNQREADYMASK(cpu) >> (newPri + 1)) {
if (!_PR_IS_NATIVE_THREAD(me))
_PR_SET_RESCHED_FLAG();
}
_PR_RUNQ_UNLOCK(cpu);
break;
case _PR_RUNNABLE:
_PR_RUNQ_LOCK(cpu);
/* Move to different runQ */
_PR_DEL_RUNQ(thread);
thread->priority = newPri;
PR_ASSERT(!(thread->flags & _PR_IDLE_THREAD));
_PR_ADD_RUNQ(thread, cpu, newPri);
_PR_RUNQ_UNLOCK(cpu);
if (newPri > me->priority) {
if (!_PR_IS_NATIVE_THREAD(me))
_PR_SET_RESCHED_FLAG();
}
break;
case _PR_LOCK_WAIT:
case _PR_COND_WAIT:
case _PR_IO_WAIT:
case _PR_SUSPENDED:
thread->priority = newPri;
break;
}
}
_PR_THREAD_UNLOCK(thread);
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSON(is);
}
/*
** Suspend the named thread and copy its gc registers into regBuf
*/
static void _PR_Suspend(PRThread *thread)
{
PRIntn is;
PRThread *me = _PR_MD_CURRENT_THREAD();
PR_ASSERT(thread != me);
PR_ASSERT(!_PR_IS_NATIVE_THREAD(thread) || (!thread->cpu));
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSOFF(is);
_PR_THREAD_LOCK(thread);
switch (thread->state) {
case _PR_RUNNABLE:
if (!_PR_IS_NATIVE_THREAD(thread)) {
_PR_RUNQ_LOCK(thread->cpu);
_PR_DEL_RUNQ(thread);
_PR_RUNQ_UNLOCK(thread->cpu);
_PR_MISCQ_LOCK(thread->cpu);
_PR_ADD_SUSPENDQ(thread, thread->cpu);
_PR_MISCQ_UNLOCK(thread->cpu);
} else {
/*
* Only LOCAL threads are suspended by _PR_Suspend
*/
PR_ASSERT(0);
}
thread->state = _PR_SUSPENDED;
break;
case _PR_RUNNING:
/*
* The thread being suspended should be a LOCAL thread with
* _pr_numCPUs == 1. Hence, the thread cannot be in RUNNING state
*/
PR_ASSERT(0);
break;
case _PR_LOCK_WAIT:
case _PR_IO_WAIT:
case _PR_COND_WAIT:
if (_PR_IS_NATIVE_THREAD(thread)) {
_PR_MD_SUSPEND_THREAD(thread);
}
thread->flags |= _PR_SUSPENDING;
break;
default:
PR_Abort();
}
_PR_THREAD_UNLOCK(thread);
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSON(is);
}
static void _PR_Resume(PRThread *thread)
{
PRThreadPriority pri;
PRIntn is;
PRThread *me = _PR_MD_CURRENT_THREAD();
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSOFF(is);
_PR_THREAD_LOCK(thread);
switch (thread->state) {
case _PR_SUSPENDED:
thread->state = _PR_RUNNABLE;
thread->flags &= ~_PR_SUSPENDING;
if (!_PR_IS_NATIVE_THREAD(thread)) {
_PR_MISCQ_LOCK(thread->cpu);
_PR_DEL_SUSPENDQ(thread);
_PR_MISCQ_UNLOCK(thread->cpu);
pri = thread->priority;
_PR_RUNQ_LOCK(thread->cpu);
_PR_ADD_RUNQ(thread, thread->cpu, pri);
_PR_RUNQ_UNLOCK(thread->cpu);
if (pri > _PR_MD_CURRENT_THREAD()->priority) {
if (!_PR_IS_NATIVE_THREAD(me))
_PR_SET_RESCHED_FLAG();
}
} else {
PR_ASSERT(0);
}
break;
case _PR_IO_WAIT:
case _PR_COND_WAIT:
thread->flags &= ~_PR_SUSPENDING;
/* PR_ASSERT(thread->wait.monitor->stickyCount == 0); */
break;
case _PR_LOCK_WAIT:
{
PRLock *wLock = thread->wait.lock;
thread->flags &= ~_PR_SUSPENDING;
_PR_LOCK_LOCK(wLock);
if (thread->wait.lock->owner == 0) {
_PR_UnblockLockWaiter(thread->wait.lock);
}
_PR_LOCK_UNLOCK(wLock);
break;
}
case _PR_RUNNABLE:
break;
case _PR_RUNNING:
/*
* The thread being suspended should be a LOCAL thread with
* _pr_numCPUs == 1. Hence, the thread cannot be in RUNNING state
*/
PR_ASSERT(0);
break;
default:
/*
* thread should have been in one of the above-listed blocked states
* (_PR_JOIN_WAIT, _PR_IO_WAIT, _PR_UNBORN, _PR_DEAD_STATE)
*/
PR_Abort();
}
_PR_THREAD_UNLOCK(thread);
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSON(is);
}
#if !defined(_PR_LOCAL_THREADS_ONLY) && defined(XP_UNIX)
static PRThread *get_thread(_PRCPU *cpu, PRBool *wakeup_cpus)
{
PRThread *thread;
PRIntn pri;
PRUint32 r;
PRCList *qp;
PRIntn priMin, priMax;
_PR_RUNQ_LOCK(cpu);
r = _PR_RUNQREADYMASK(cpu);
if (r==0) {
priMin = priMax = PR_PRIORITY_FIRST;
} else if (r == (1<<PR_PRIORITY_NORMAL) ) {
priMin = priMax = PR_PRIORITY_NORMAL;
} else {
priMin = PR_PRIORITY_FIRST;
priMax = PR_PRIORITY_LAST;
}
thread = NULL;
for (pri = priMax; pri >= priMin ; pri-- ) {
if (r & (1 << pri)) {
for (qp = _PR_RUNQ(cpu)[pri].next;
qp != &_PR_RUNQ(cpu)[pri];
qp = qp->next) {
thread = _PR_THREAD_PTR(qp);
/*
* skip non-schedulable threads
*/
PR_ASSERT(!(thread->flags & _PR_IDLE_THREAD));
if (thread->no_sched) {
thread = NULL;
/*
* Need to wakeup cpus to avoid missing a
* runnable thread
* Waking up all CPU's need happen only once.
*/
*wakeup_cpus = PR_TRUE;
continue;
} else if (thread->flags & _PR_BOUND_THREAD) {
/*
* Thread bound to cpu 0
*/
thread = NULL;
#ifdef IRIX
_PR_MD_WAKEUP_PRIMORDIAL_CPU();
#endif
continue;
} else if (thread->io_pending == PR_TRUE) {
/*
* A thread that is blocked for I/O needs to run
* on the same cpu on which it was blocked. This is because
* the cpu's ioq is accessed without lock protection and scheduling
* the thread on a different cpu would preclude this optimization.
*/
thread = NULL;
continue;
} else {
/* Pull thread off of its run queue */
_PR_DEL_RUNQ(thread);
_PR_RUNQ_UNLOCK(cpu);
return(thread);
}
}
}
thread = NULL;
}
_PR_RUNQ_UNLOCK(cpu);
return(thread);
}
#endif /* !defined(_PR_LOCAL_THREADS_ONLY) && defined(XP_UNIX) */
/*
** Schedule this native thread by finding the highest priority nspr
** thread that is ready to run.
**
** Note- everyone really needs to call _PR_MD_SWITCH_CONTEXT (which calls
** PR_Schedule() rather than calling PR_Schedule. Otherwise if there
** is initialization required for switching from SWITCH_CONTEXT,
** it will not get done!
*/
void _PR_Schedule(void)
{
PRThread *thread, *me = _PR_MD_CURRENT_THREAD();
_PRCPU *cpu = _PR_MD_CURRENT_CPU();
PRIntn pri;
PRUint32 r;
PRCList *qp;
PRIntn priMin, priMax;
#if !defined(_PR_LOCAL_THREADS_ONLY) && defined(XP_UNIX)
PRBool wakeup_cpus;
#endif
/* Interrupts must be disabled */
PR_ASSERT(_PR_IS_NATIVE_THREAD(me) || _PR_MD_GET_INTSOFF() != 0);
/* Since we are rescheduling, we no longer want to */
_PR_CLEAR_RESCHED_FLAG();
/*
** Find highest priority thread to run. Bigger priority numbers are
** higher priority threads
*/
_PR_RUNQ_LOCK(cpu);
/*
* if we are in SuspendAll mode, can schedule only the thread
* that called PR_SuspendAll
*
* The thread may be ready to run now, after completing an I/O
* operation, for example
*/
if ((thread = suspendAllThread) != 0) {
if ((!(thread->no_sched)) && (thread->state == _PR_RUNNABLE)) {
/* Pull thread off of its run queue */
_PR_DEL_RUNQ(thread);
_PR_RUNQ_UNLOCK(cpu);
goto found_thread;
} else {
thread = NULL;
_PR_RUNQ_UNLOCK(cpu);
goto idle_thread;
}
}
r = _PR_RUNQREADYMASK(cpu);
if (r==0) {
priMin = priMax = PR_PRIORITY_FIRST;
} else if (r == (1<<PR_PRIORITY_NORMAL) ) {
priMin = priMax = PR_PRIORITY_NORMAL;
} else {
priMin = PR_PRIORITY_FIRST;
priMax = PR_PRIORITY_LAST;
}
thread = NULL;
for (pri = priMax; pri >= priMin ; pri-- ) {
if (r & (1 << pri)) {
for (qp = _PR_RUNQ(cpu)[pri].next;
qp != &_PR_RUNQ(cpu)[pri];
qp = qp->next) {
thread = _PR_THREAD_PTR(qp);
/*
* skip non-schedulable threads
*/
PR_ASSERT(!(thread->flags & _PR_IDLE_THREAD));
if ((thread->no_sched) && (me != thread)){
thread = NULL;
continue;
} else {
/* Pull thread off of its run queue */
_PR_DEL_RUNQ(thread);
_PR_RUNQ_UNLOCK(cpu);
goto found_thread;
}
}
}
thread = NULL;
}
_PR_RUNQ_UNLOCK(cpu);
#if !defined(_PR_LOCAL_THREADS_ONLY) && defined(XP_UNIX)
wakeup_cpus = PR_FALSE;
_PR_CPU_LIST_LOCK();
for (qp = _PR_CPUQ().next; qp != &_PR_CPUQ(); qp = qp->next) {
if (cpu != _PR_CPU_PTR(qp)) {
if ((thread = get_thread(_PR_CPU_PTR(qp), &wakeup_cpus))
!= NULL) {
thread->cpu = cpu;
_PR_CPU_LIST_UNLOCK();
if (wakeup_cpus == PR_TRUE)
_PR_MD_WAKEUP_CPUS();
goto found_thread;
}
}
}
_PR_CPU_LIST_UNLOCK();
if (wakeup_cpus == PR_TRUE)
_PR_MD_WAKEUP_CPUS();
#endif /* _PR_LOCAL_THREADS_ONLY */
idle_thread:
/*
** There are no threads to run. Switch to the idle thread
*/
PR_LOG(_pr_sched_lm, PR_LOG_MAX, ("pausing"));
thread = _PR_MD_CURRENT_CPU()->idle_thread;
found_thread:
PR_ASSERT((me == thread) || ((thread->state == _PR_RUNNABLE) &&
(!(thread->no_sched))));
/* Resume the thread */
PR_LOG(_pr_sched_lm, PR_LOG_MAX,
("switching to %d[%p]", thread->id, thread));
PR_ASSERT(thread->state != _PR_RUNNING);
thread->state = _PR_RUNNING;
/* If we are on the runq, it just means that we went to sleep on some
* resource, and by the time we got here another real native thread had
* already given us the resource and put us back on the runqueue
*/
PR_ASSERT(thread->cpu == _PR_MD_CURRENT_CPU());
if (thread != me)
_PR_MD_RESTORE_CONTEXT(thread);
#if 0
/* XXXMB; with setjmp/longjmp it is impossible to land here, but
* it is not with fibers... Is this a bad thing? I believe it is
* still safe.
*/
PR_NOT_REACHED("impossible return from schedule");
#endif
}
/*
** Attaches a thread.
** Does not set the _PR_MD_CURRENT_THREAD.
** Does not specify the scope of the thread.
*/
static PRThread *
_PR_AttachThread(PRThreadType type, PRThreadPriority priority,
PRThreadStack *stack)
{
PRThread *thread;
char *mem;
if (priority > PR_PRIORITY_LAST) {
priority = PR_PRIORITY_LAST;
} else if (priority < PR_PRIORITY_FIRST) {
priority = PR_PRIORITY_FIRST;
}
mem = (char*) PR_CALLOC(sizeof(PRThread));
if (mem) {
thread = (PRThread*) mem;
thread->priority = priority;
thread->stack = stack;
thread->state = _PR_RUNNING;
PR_INIT_CLIST(&thread->lockList);
if (_PR_MD_NEW_LOCK(&thread->threadLock) == PR_FAILURE) {
PR_DELETE(thread);
return 0;
}
return thread;
}
return 0;
}
PR_IMPLEMENT(PRThread*)
_PR_NativeCreateThread(PRThreadType type,
void (*start)(void *arg),
void *arg,
PRThreadPriority priority,
PRThreadScope scope,
PRThreadState state,
PRUint32 stackSize,
PRUint32 flags)
{
PRThread *thread;
thread = _PR_AttachThread(type, priority, NULL);
if (thread) {
PR_Lock(_pr_activeLock);
thread->flags = (flags | _PR_GLOBAL_SCOPE);
thread->id = ++_pr_utid;
if (type == PR_SYSTEM_THREAD) {
thread->flags |= _PR_SYSTEM;
_pr_systemActive++;
} else {
_pr_userActive++;
}
PR_Unlock(_pr_activeLock);
thread->stack = PR_NEWZAP(PRThreadStack);
if (!thread->stack) {
PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
goto done;
}
thread->stack->stackSize = stackSize?stackSize:_MD_DEFAULT_STACK_SIZE;
thread->stack->thr = thread;
thread->startFunc = start;
thread->arg = arg;
/*
Set thread flags related to scope and joinable state. If joinable
thread, allocate a "termination" conidition variable.
*/
if (state == PR_JOINABLE_THREAD) {
thread->term = PR_NewCondVar(_pr_terminationCVLock);
if (thread->term == NULL) {
PR_DELETE(thread->stack);
goto done;
}
}
thread->state = _PR_RUNNING;
if (_PR_MD_CREATE_THREAD(thread, _PR_NativeRunThread, priority,
scope,state,stackSize) == PR_SUCCESS) {
return thread;
}
if (thread->term) {
PR_DestroyCondVar(thread->term);
thread->term = NULL;
}
PR_DELETE(thread->stack);
}
done:
if (thread) {
_PR_DecrActiveThreadCount(thread);
_PR_DestroyThread(thread);
}
return NULL;
}
/************************************************************************/
PR_IMPLEMENT(PRThread*) _PR_CreateThread(PRThreadType type,
void (*start)(void *arg),
void *arg,
PRThreadPriority priority,
PRThreadScope scope,
PRThreadState state,
PRUint32 stackSize,
PRUint32 flags)
{
PRThread *me;
PRThread *thread = NULL;
PRThreadStack *stack;
char *top;
PRIntn is;
PRIntn native = 0;
PRIntn useRecycled = 0;
PRBool status;
/*
First, pin down the priority. Not all compilers catch passing out of
range enum here. If we let bad values thru, priority queues won't work.
*/
if (priority > PR_PRIORITY_LAST) {
priority = PR_PRIORITY_LAST;
} else if (priority < PR_PRIORITY_FIRST) {
priority = PR_PRIORITY_FIRST;
}
if (!_pr_initialized) _PR_ImplicitInitialization();
if (! (flags & _PR_IDLE_THREAD))
me = _PR_MD_CURRENT_THREAD();
#if defined(_PR_GLOBAL_THREADS_ONLY)
/*
* can create global threads only
*/
if (scope == PR_LOCAL_THREAD)
scope = PR_GLOBAL_THREAD;
#endif
if (_native_threads_only)
scope = PR_GLOBAL_THREAD;
native = (((scope == PR_GLOBAL_THREAD)|| (scope == PR_GLOBAL_BOUND_THREAD))
&& _PR_IS_NATIVE_THREAD_SUPPORTED());
_PR_ADJUST_STACKSIZE(stackSize);
if (native) {
/*
* clear the IDLE_THREAD flag which applies to LOCAL
* threads only
*/
flags &= ~_PR_IDLE_THREAD;
flags |= _PR_GLOBAL_SCOPE;
if (_PR_NUM_DEADNATIVE > 0) {
_PR_DEADQ_LOCK;
if (_PR_NUM_DEADNATIVE == 0) { /* Thread safe check */
_PR_DEADQ_UNLOCK;
} else {
thread = _PR_THREAD_PTR(_PR_DEADNATIVEQ.next);
PR_REMOVE_LINK(&thread->links);
_PR_DEC_DEADNATIVE;
_PR_DEADQ_UNLOCK;
_PR_InitializeRecycledThread(thread);
thread->startFunc = start;
thread->arg = arg;
thread->flags = (flags | _PR_GLOBAL_SCOPE);
if (type == PR_SYSTEM_THREAD)
{
thread->flags |= _PR_SYSTEM;
PR_ATOMIC_INCREMENT(&_pr_systemActive);
}
else PR_ATOMIC_INCREMENT(&_pr_userActive);
if (state == PR_JOINABLE_THREAD) {
if (!thread->term)
thread->term = PR_NewCondVar(_pr_terminationCVLock);
}
else {
if(thread->term) {
PR_DestroyCondVar(thread->term);
thread->term = 0;
}
}
thread->priority = priority;
_PR_MD_SET_PRIORITY(&(thread->md), priority);
/* XXX what about stackSize? */
thread->state = _PR_RUNNING;
_PR_MD_WAKEUP_WAITER(thread);
return thread;
}
}
thread = _PR_NativeCreateThread(type, start, arg, priority,
scope, state, stackSize, flags);
} else {
if (_PR_NUM_DEADUSER > 0) {
_PR_DEADQ_LOCK;
if (_PR_NUM_DEADUSER == 0) { /* thread safe check */
_PR_DEADQ_UNLOCK;
} else {
PRCList *ptr;
/* Go down list checking for a recycled thread with a
* large enough stack. XXXMB - this has a bad degenerate case.
*/
ptr = _PR_DEADUSERQ.next;
while( ptr != &_PR_DEADUSERQ ) {
thread = _PR_THREAD_PTR(ptr);
if ((thread->stack->stackSize >= stackSize) &&
(!thread->no_sched)) {
PR_REMOVE_LINK(&thread->links);
_PR_DEC_DEADUSER;
break;
} else {
ptr = ptr->next;
thread = NULL;
}
}
_PR_DEADQ_UNLOCK;
if (thread) {
_PR_InitializeRecycledThread(thread);
thread->startFunc = start;
thread->arg = arg;
thread->priority = priority;
if (state == PR_JOINABLE_THREAD) {
if (!thread->term)
thread->term = PR_NewCondVar(_pr_terminationCVLock);
} else {
if(thread->term) {
PR_DestroyCondVar(thread->term);
thread->term = 0;
}
}
useRecycled++;
}
}
}
if (thread == NULL) {
#ifndef HAVE_CUSTOM_USER_THREADS
stack = _PR_NewStack(stackSize);
if (!stack) {
PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
return NULL;
}
/* Allocate thread object and per-thread data off the top of the stack*/
top = stack->stackTop;
#ifdef HAVE_STACK_GROWING_UP
thread = (PRThread*) top;
top = top + sizeof(PRThread);
/*
* Make stack 64-byte aligned
*/
if ((PRUptrdiff)top & 0x3f) {
top = (char*)(((PRUptrdiff)top + 0x40) & ~0x3f);
}
#else
top = top - sizeof(PRThread);
thread = (PRThread*) top;
/*
* Make stack 64-byte aligned
*/
if ((PRUptrdiff)top & 0x3f) {
top = (char*)((PRUptrdiff)top & ~0x3f);
}
#endif
#if defined(GC_LEAK_DETECTOR)
/*
* sorry, it is not safe to allocate the thread on the stack,
* because we assign to this object before the GC can learn
* about this thread. we'll just leak thread objects instead.
*/
thread = PR_NEW(PRThread);
#endif
stack->thr = thread;
memset(thread, 0, sizeof(PRThread));
thread->threadAllocatedOnStack = 1;
#else
thread = _PR_MD_CREATE_USER_THREAD(stackSize, start, arg);
if (!thread) {
PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
return NULL;
}
thread->threadAllocatedOnStack = 0;
stack = NULL;
top = NULL;
#endif
/* Initialize thread */
thread->tpdLength = 0;
thread->privateData = NULL;
thread->stack = stack;
thread->priority = priority;
thread->startFunc = start;
thread->arg = arg;
PR_INIT_CLIST(&thread->lockList);
if (_PR_MD_INIT_THREAD(thread) == PR_FAILURE) {
if (thread->threadAllocatedOnStack == 1)
_PR_FreeStack(thread->stack);
else {
PR_DELETE(thread);
}
PR_SetError(PR_INSUFFICIENT_RESOURCES_ERROR, 0);
return NULL;
}
if (_PR_MD_NEW_LOCK(&thread->threadLock) == PR_FAILURE) {
if (thread->threadAllocatedOnStack == 1)
_PR_FreeStack(thread->stack);
else {
PR_DELETE(thread->privateData);
PR_DELETE(thread);
}
PR_SetError(PR_INSUFFICIENT_RESOURCES_ERROR, 0);
return NULL;
}
_PR_MD_INIT_CONTEXT(thread, top, _PR_UserRunThread, &status);
if (status == PR_FALSE) {
_PR_MD_FREE_LOCK(&thread->threadLock);
if (thread->threadAllocatedOnStack == 1)
_PR_FreeStack(thread->stack);
else {
PR_DELETE(thread->privateData);
PR_DELETE(thread);
}
return NULL;
}
/*
Set thread flags related to scope and joinable state. If joinable
thread, allocate a "termination" condition variable.
*/
if (state == PR_JOINABLE_THREAD) {
thread->term = PR_NewCondVar(_pr_terminationCVLock);
if (thread->term == NULL) {
_PR_MD_FREE_LOCK(&thread->threadLock);
if (thread->threadAllocatedOnStack == 1)
_PR_FreeStack(thread->stack);
else {
PR_DELETE(thread->privateData);
PR_DELETE(thread);
}
return NULL;
}
}
}
/* Update thread type counter */
PR_Lock(_pr_activeLock);
thread->flags = flags;
thread->id = ++_pr_utid;
if (type == PR_SYSTEM_THREAD) {
thread->flags |= _PR_SYSTEM;
_pr_systemActive++;
} else {
_pr_userActive++;
}
/* Make thread runnable */
thread->state = _PR_RUNNABLE;
/*
* Add to list of active threads
*/
PR_Unlock(_pr_activeLock);
if ((! (thread->flags & _PR_IDLE_THREAD)) && _PR_IS_NATIVE_THREAD(me) )
thread->cpu = _PR_GetPrimordialCPU();
else
thread->cpu = _PR_MD_CURRENT_CPU();
PR_ASSERT(!_PR_IS_NATIVE_THREAD(thread));
if ((! (thread->flags & _PR_IDLE_THREAD)) && !_PR_IS_NATIVE_THREAD(me)) {
_PR_INTSOFF(is);
_PR_RUNQ_LOCK(thread->cpu);
_PR_ADD_RUNQ(thread, thread->cpu, priority);
_PR_RUNQ_UNLOCK(thread->cpu);
}
if (thread->flags & _PR_IDLE_THREAD) {
/*
** If the creating thread is a kernel thread, we need to
** awaken the user thread idle thread somehow; potentially
** it could be sleeping in its idle loop, and we need to poke
** it. To do so, wake the idle thread...
*/
_PR_MD_WAKEUP_WAITER(NULL);
} else if (_PR_IS_NATIVE_THREAD(me)) {
_PR_MD_WAKEUP_WAITER(thread);
}
if ((! (thread->flags & _PR_IDLE_THREAD)) && !_PR_IS_NATIVE_THREAD(me) )
_PR_INTSON(is);
}
return thread;
}
PR_IMPLEMENT(PRThread*) PR_CreateThread(PRThreadType type,
void (*start)(void *arg),
void *arg,
PRThreadPriority priority,
PRThreadScope scope,
PRThreadState state,
PRUint32 stackSize)
{
return _PR_CreateThread(type, start, arg, priority, scope, state,
stackSize, 0);
}
/*
** Associate a thread object with an existing native thread.
** "type" is the type of thread object to attach
** "priority" is the priority to assign to the thread
** "stack" defines the shape of the threads stack
**
** This can return NULL if some kind of error occurs, or if memory is
** tight.
**
** This call is not normally needed unless you create your own native
** thread. PR_Init does this automatically for the primordial thread.
*/
PRThread* _PRI_AttachThread(PRThreadType type,
PRThreadPriority priority, PRThreadStack *stack, PRUint32 flags)
{
PRThread *thread;
if ((thread = _PR_MD_GET_ATTACHED_THREAD()) != NULL) {
return thread;
}
_PR_MD_SET_CURRENT_THREAD(NULL);
/* Clear out any state if this thread was attached before */
_PR_MD_SET_CURRENT_CPU(NULL);
thread = _PR_AttachThread(type, priority, stack);
if (thread) {
PRIntn is;
_PR_MD_SET_CURRENT_THREAD(thread);
thread->flags = flags | _PR_GLOBAL_SCOPE | _PR_ATTACHED;
if (!stack) {
thread->stack = PR_NEWZAP(PRThreadStack);
if (!thread->stack) {
_PR_DestroyThread(thread);
return NULL;
}
thread->stack->stackSize = _MD_DEFAULT_STACK_SIZE;
}
PR_INIT_CLIST(&thread->links);
if (_PR_MD_INIT_ATTACHED_THREAD(thread) == PR_FAILURE) {
PR_DELETE(thread->stack);
_PR_DestroyThread(thread);
return NULL;
}
_PR_MD_SET_CURRENT_CPU(NULL);
if (_PR_MD_CURRENT_CPU()) {
_PR_INTSOFF(is);
PR_Lock(_pr_activeLock);
}
if (type == PR_SYSTEM_THREAD) {
thread->flags |= _PR_SYSTEM;
_pr_systemActive++;
} else {
_pr_userActive++;
}
if (_PR_MD_CURRENT_CPU()) {
PR_Unlock(_pr_activeLock);
_PR_INTSON(is);
}
}
return thread;
}
PR_IMPLEMENT(PRThread*) PR_AttachThread(PRThreadType type,
PRThreadPriority priority, PRThreadStack *stack)
{
return PR_GetCurrentThread();
}
PR_IMPLEMENT(void) PR_DetachThread(void)
{
/*
* On IRIX, Solaris, and Windows, foreign threads are detached when
* they terminate.
*/
#if !defined(IRIX) && !defined(WIN32) \
&& !(defined(SOLARIS) && defined(_PR_GLOBAL_THREADS_ONLY))
PRThread *me;
if (_pr_initialized) {
me = _PR_MD_GET_ATTACHED_THREAD();
if ((me != NULL) && (me->flags & _PR_ATTACHED))
_PRI_DetachThread();
}
#endif
}
void _PRI_DetachThread(void)
{
PRThread *me = _PR_MD_CURRENT_THREAD();
if (me->flags & _PR_PRIMORDIAL) {
/*
* ignore, if primordial thread
*/
return;
}
PR_ASSERT(me->flags & _PR_ATTACHED);
PR_ASSERT(_PR_IS_NATIVE_THREAD(me));
_PR_CleanupThread(me);
PR_DELETE(me->privateData);
_PR_DecrActiveThreadCount(me);
_PR_MD_CLEAN_THREAD(me);
_PR_MD_SET_CURRENT_THREAD(NULL);
if (!me->threadAllocatedOnStack)
PR_DELETE(me->stack);
_PR_MD_FREE_LOCK(&me->threadLock);
PR_DELETE(me);
}
/*
** Wait for thread termination:
** "thread" is the target thread
**
** This can return PR_FAILURE if no joinable thread could be found
** corresponding to the specified target thread.
**
** The calling thread is suspended until the target thread completes.
** Several threads cannot wait for the same thread to complete; one thread
** will complete successfully and others will terminate with an error PR_FAILURE.
** The calling thread will not be blocked if the target thread has already
** terminated.
*/
PR_IMPLEMENT(PRStatus) PR_JoinThread(PRThread *thread)
{
PRIntn is;
PRCondVar *term;
PRThread *me = _PR_MD_CURRENT_THREAD();
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSOFF(is);
term = thread->term;
/* can't join a non-joinable thread */
if (term == NULL) {
PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
goto ErrorExit;
}
/* multiple threads can't wait on the same joinable thread */
if (term->condQ.next != &term->condQ) {
goto ErrorExit;
}
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSON(is);
/* wait for the target thread's termination cv invariant */
PR_Lock (_pr_terminationCVLock);
while (thread->state != _PR_JOIN_WAIT) {
(void) PR_WaitCondVar(term, PR_INTERVAL_NO_TIMEOUT);
}
(void) PR_Unlock (_pr_terminationCVLock);
/*
Remove target thread from global waiting to join Q; make it runnable
again and put it back on its run Q. When it gets scheduled later in
_PR_RunThread code, it will clean up its stack.
*/
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSOFF(is);
thread->state = _PR_RUNNABLE;
if ( !_PR_IS_NATIVE_THREAD(thread) ) {
_PR_THREAD_LOCK(thread);
_PR_MISCQ_LOCK(thread->cpu);
_PR_DEL_JOINQ(thread);
_PR_MISCQ_UNLOCK(thread->cpu);
_PR_AddThreadToRunQ(me, thread);
_PR_THREAD_UNLOCK(thread);
}
if (!_PR_IS_NATIVE_THREAD(me))
_PR_INTSON(is);
_PR_MD_WAKEUP_WAITER(thread);
return PR_SUCCESS;
ErrorExit:
if ( !_PR_IS_NATIVE_THREAD(me)) _PR_INTSON(is);
return PR_FAILURE;
}
PR_IMPLEMENT(void) PR_SetThreadPriority(PRThread *thread,
PRThreadPriority newPri)
{
/*
First, pin down the priority. Not all compilers catch passing out of
range enum here. If we let bad values thru, priority queues won't work.
*/
if ((PRIntn)newPri > (PRIntn)PR_PRIORITY_LAST) {
newPri = PR_PRIORITY_LAST;
} else if ((PRIntn)newPri < (PRIntn)PR_PRIORITY_FIRST) {
newPri = PR_PRIORITY_FIRST;
}
if ( _PR_IS_NATIVE_THREAD(thread) ) {
thread->priority = newPri;
_PR_MD_SET_PRIORITY(&(thread->md), newPri);
} else _PR_SetThreadPriority(thread, newPri);
}
/*
** This routine prevents all other threads from running. This call is needed by
** the garbage collector.
*/
PR_IMPLEMENT(void) PR_SuspendAll(void)
{
PRThread *me = _PR_MD_CURRENT_THREAD();
PRCList *qp;
/*
* Stop all user and native threads which are marked GC able.
*/
PR_Lock(_pr_activeLock);
suspendAllOn = PR_TRUE;
suspendAllThread = _PR_MD_CURRENT_THREAD();
_PR_MD_BEGIN_SUSPEND_ALL();
for (qp = _PR_ACTIVE_LOCAL_THREADQ().next;
qp != &_PR_ACTIVE_LOCAL_THREADQ(); qp = qp->next) {
if ((me != _PR_ACTIVE_THREAD_PTR(qp)) &&
_PR_IS_GCABLE_THREAD(_PR_ACTIVE_THREAD_PTR(qp))) {
_PR_Suspend(_PR_ACTIVE_THREAD_PTR(qp));
PR_ASSERT((_PR_ACTIVE_THREAD_PTR(qp))->state != _PR_RUNNING);
}
}
for (qp = _PR_ACTIVE_GLOBAL_THREADQ().next;
qp != &_PR_ACTIVE_GLOBAL_THREADQ(); qp = qp->next) {
if ((me != _PR_ACTIVE_THREAD_PTR(qp)) &&
_PR_IS_GCABLE_THREAD(_PR_ACTIVE_THREAD_PTR(qp)))
/* PR_Suspend(_PR_ACTIVE_THREAD_PTR(qp)); */
_PR_MD_SUSPEND_THREAD(_PR_ACTIVE_THREAD_PTR(qp));
}
_PR_MD_END_SUSPEND_ALL();
}
/*
** This routine unblocks all other threads that were suspended from running by
** PR_SuspendAll(). This call is needed by the garbage collector.
*/
PR_IMPLEMENT(void) PR_ResumeAll(void)
{
PRThread *me = _PR_MD_CURRENT_THREAD();
PRCList *qp;
/*
* Resume all user and native threads which are marked GC able.
*/
_PR_MD_BEGIN_RESUME_ALL();
for (qp = _PR_ACTIVE_LOCAL_THREADQ().next;
qp != &_PR_ACTIVE_LOCAL_THREADQ(); qp = qp->next) {
if ((me != _PR_ACTIVE_THREAD_PTR(qp)) &&
_PR_IS_GCABLE_THREAD(_PR_ACTIVE_THREAD_PTR(qp)))
_PR_Resume(_PR_ACTIVE_THREAD_PTR(qp));
}
for (qp = _PR_ACTIVE_GLOBAL_THREADQ().next;
qp != &_PR_ACTIVE_GLOBAL_THREADQ(); qp = qp->next) {
if ((me != _PR_ACTIVE_THREAD_PTR(qp)) &&
_PR_IS_GCABLE_THREAD(_PR_ACTIVE_THREAD_PTR(qp)))
_PR_MD_RESUME_THREAD(_PR_ACTIVE_THREAD_PTR(qp));
}
_PR_MD_END_RESUME_ALL();
suspendAllThread = NULL;
suspendAllOn = PR_FALSE;
PR_Unlock(_pr_activeLock);
}
PR_IMPLEMENT(PRStatus) PR_EnumerateThreads(PREnumerator func, void *arg)
{
PRCList *qp, *qp_next;
PRIntn i = 0;
PRStatus rv = PR_SUCCESS;
PRThread* t;
/*
** Currently Enumerate threads happen only with suspension and
** pr_activeLock held
*/
PR_ASSERT(suspendAllOn);
/* Steve Morse, 4-23-97: Note that we can't walk a queue by taking
* qp->next after applying the function "func". In particular, "func"
* might remove the thread from the queue and put it into another one in
* which case qp->next no longer points to the next entry in the original
* queue.
*
* To get around this problem, we save qp->next in qp_next before applying
* "func" and use that saved value as the next value after applying "func".
*/
/*
* Traverse the list of local and global threads
*/
for (qp = _PR_ACTIVE_LOCAL_THREADQ().next;
qp != &_PR_ACTIVE_LOCAL_THREADQ(); qp = qp_next)
{
qp_next = qp->next;
t = _PR_ACTIVE_THREAD_PTR(qp);
if (_PR_IS_GCABLE_THREAD(t))
{
rv = (*func)(t, i, arg);
if (rv != PR_SUCCESS)
return rv;
i++;
}
}
for (qp = _PR_ACTIVE_GLOBAL_THREADQ().next;
qp != &_PR_ACTIVE_GLOBAL_THREADQ(); qp = qp_next)
{
qp_next = qp->next;
t = _PR_ACTIVE_THREAD_PTR(qp);
if (_PR_IS_GCABLE_THREAD(t))
{
rv = (*func)(t, i, arg);
if (rv != PR_SUCCESS)
return rv;
i++;
}
}
return rv;
}
/* FUNCTION: _PR_AddSleepQ
** DESCRIPTION:
** Adds a thread to the sleep/pauseQ.
** RESTRICTIONS:
** Caller must have the RUNQ lock.
** Caller must be a user level thread
*/
PR_IMPLEMENT(void)
_PR_AddSleepQ(PRThread *thread, PRIntervalTime timeout)
{
_PRCPU *cpu = thread->cpu;
if (timeout == PR_INTERVAL_NO_TIMEOUT) {
/* append the thread to the global pause Q */
PR_APPEND_LINK(&thread->links, &_PR_PAUSEQ(thread->cpu));
thread->flags |= _PR_ON_PAUSEQ;
} else {
PRIntervalTime sleep;
PRCList *q;
PRThread *t;
/* sort onto global sleepQ */
sleep = timeout;
/* Check if we are longest timeout */
if (timeout >= _PR_SLEEPQMAX(cpu)) {
PR_INSERT_BEFORE(&thread->links, &_PR_SLEEPQ(cpu));
thread->sleep = timeout - _PR_SLEEPQMAX(cpu);
_PR_SLEEPQMAX(cpu) = timeout;
} else {
/* Sort thread into global sleepQ at appropriate point */
q = _PR_SLEEPQ(cpu).next;
/* Now scan the list for where to insert this entry */
while (q != &_PR_SLEEPQ(cpu)) {
t = _PR_THREAD_PTR(q);
if (sleep < t->sleep) {
/* Found sleeper to insert in front of */
break;
}
sleep -= t->sleep;
q = q->next;
}
thread->sleep = sleep;
PR_INSERT_BEFORE(&thread->links, q);
/*
** Subtract our sleep time from the sleeper that follows us (there
** must be one) so that they remain relative to us.
*/
PR_ASSERT (thread->links.next != &_PR_SLEEPQ(cpu));
t = _PR_THREAD_PTR(thread->links.next);
PR_ASSERT(_PR_THREAD_PTR(t->links.prev) == thread);
t->sleep -= sleep;
}
thread->flags |= _PR_ON_SLEEPQ;
}
}
/* FUNCTION: _PR_DelSleepQ
** DESCRIPTION:
** Removes a thread from the sleep/pauseQ.
** INPUTS:
** If propogate_time is true, then the thread following the deleted
** thread will be get the time from the deleted thread. This is used
** when deleting a sleeper that has not timed out.
** RESTRICTIONS:
** Caller must have the RUNQ lock.
** Caller must be a user level thread
*/
PR_IMPLEMENT(void)
_PR_DelSleepQ(PRThread *thread, PRBool propogate_time)
{
_PRCPU *cpu = thread->cpu;
/* Remove from pauseQ/sleepQ */
if (thread->flags & (_PR_ON_PAUSEQ|_PR_ON_SLEEPQ)) {
if (thread->flags & _PR_ON_SLEEPQ) {
PRCList *q = thread->links.next;
if (q != &_PR_SLEEPQ(cpu)) {
if (propogate_time == PR_TRUE) {
PRThread *after = _PR_THREAD_PTR(q);
after->sleep += thread->sleep;
} else
_PR_SLEEPQMAX(cpu) -= thread->sleep;
} else {
/* Check if prev is the beggining of the list; if so,
* we are the only element on the list.
*/
if (thread->links.prev != &_PR_SLEEPQ(cpu))
_PR_SLEEPQMAX(cpu) -= thread->sleep;
else
_PR_SLEEPQMAX(cpu) = 0;
}
thread->flags &= ~_PR_ON_SLEEPQ;
} else {
thread->flags &= ~_PR_ON_PAUSEQ;
}
PR_REMOVE_LINK(&thread->links);
} else
PR_ASSERT(0);
}
void
_PR_AddThreadToRunQ(
PRThread *me, /* the current thread */
PRThread *thread) /* the local thread to be added to a run queue */
{
PRThreadPriority pri = thread->priority;
_PRCPU *cpu = thread->cpu;
PR_ASSERT(!_PR_IS_NATIVE_THREAD(thread));
#if defined(WINNT)
/*
* On NT, we can only reliably know that the current CPU
* is not idle. We add the awakened thread to the run
* queue of its CPU if its CPU is the current CPU.
* For any other CPU, we don't really know whether it
* is busy or idle. So in all other cases, we just
* "post" the awakened thread to the IO completion port
* for the next idle CPU to execute (this is done in
* _PR_MD_WAKEUP_WAITER).
* Threads with a suspended I/O operation remain bound to
* the same cpu until I/O is cancelled
*
* NOTE: the boolean expression below must be the exact
* opposite of the corresponding boolean expression in
* _PR_MD_WAKEUP_WAITER.
*/
if ((!_PR_IS_NATIVE_THREAD(me) && (cpu == me->cpu)) ||
(thread->md.thr_bound_cpu)) {
PR_ASSERT(!thread->md.thr_bound_cpu ||
(thread->md.thr_bound_cpu == cpu));
_PR_RUNQ_LOCK(cpu);
_PR_ADD_RUNQ(thread, cpu, pri);
_PR_RUNQ_UNLOCK(cpu);
}
#else
_PR_RUNQ_LOCK(cpu);
_PR_ADD_RUNQ(thread, cpu, pri);
_PR_RUNQ_UNLOCK(cpu);
if (!_PR_IS_NATIVE_THREAD(me) && (cpu == me->cpu)) {
if (pri > me->priority) {
_PR_SET_RESCHED_FLAG();
}
}
#endif
}