WebSVN – HelenOS – Diff – /trunk/kernel/generic/src/proc/thread.c


/*
 * Copyright (C) 2001-2004 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup genericproc
 * @{
 */
 
/**
 * @file
 * @brief   Thread management functions.
 */
 
#include <proc/scheduler.h>
#include <proc/thread.h>
#include <proc/task.h>
#include <proc/uarg.h>
#include <mm/frame.h>
#include <mm/page.h>
#include <arch/asm.h>
#include <arch/cycle.h>
#include <arch.h>
#include <synch/synch.h>
#include <synch/spinlock.h>
#include <synch/waitq.h>
#include <synch/rwlock.h>
#include <cpu.h>
#include <func.h>
#include <context.h>
#include <adt/btree.h>
#include <adt/list.h>
#include <typedefs.h>
#include <time/clock.h>
#include <config.h>
#include <arch/interrupt.h>
#include <smp/ipi.h>
#include <arch/faddr.h>
#include <atomic.h>
#include <memstr.h>
#include <print.h>
#include <mm/slab.h>
#include <debug.h>
#include <main/uinit.h>
#include <syscall/copy.h>
#include <errno.h>
 
 
/** Thread states */
char *thread_states[] = {
    "Invalid",
    "Running",
    "Sleeping",
    "Ready",
    "Entering",
    "Exiting",
    "Undead"
};
 
/** Lock protecting the threads_btree B+tree. For locking rules, see declaration thereof. */
SPINLOCK_INITIALIZE(threads_lock);
 
/** B+tree of all threads.
 *
 * When a thread is found in the threads_btree B+tree, it is guaranteed to exist as long
 * as the threads_lock is held.
 */
btree_t threads_btree;     
 
SPINLOCK_INITIALIZE(tidlock);
uint32_t last_tid = 0;
 
static slab_cache_t *thread_slab;
#ifdef ARCH_HAS_FPU
slab_cache_t *fpu_context_slab;
#endif
 
/** Thread wrapper
 *
 * This wrapper is provided to ensure that every thread
 * makes a call to thread_exit() when its implementing
 * function returns.
 *
 * interrupts_disable() is assumed.
 *
 */
static void cushion(void)
{
    void (*f)(void *) = THREAD->thread_code;
    void *arg = THREAD->thread_arg;
    THREAD->last_cycle = get_cycle();
 
    /* This is where each thread wakes up after its creation */
    spinlock_unlock(&THREAD->lock);
    interrupts_enable();
 
    f(arg);
   
    /* Accumulate accounting to the task */
    ipl_t ipl = interrupts_disable();
   
    spinlock_lock(&THREAD->lock);
    if (!THREAD->uncounted) {
        thread_update_accounting();
        uint64_t cycles = THREAD->cycles;
        THREAD->cycles = 0;
        spinlock_unlock(&THREAD->lock);
       
        spinlock_lock(&TASK->lock);
        TASK->cycles += cycles;
        spinlock_unlock(&TASK->lock);
    } else
        spinlock_unlock(&THREAD->lock);
   
    interrupts_restore(ipl);
   
    thread_exit();
    /* not reached */
}
 
/** Initialization and allocation for thread_t structure */
static int thr_constructor(void *obj, int kmflags)
{
    thread_t *t = (thread_t *) obj;
 
    spinlock_initialize(&t->lock, "thread_t_lock");
    link_initialize(&t->rq_link);
    link_initialize(&t->wq_link);
    link_initialize(&t->th_link);
 
    /* call the architecture-specific part of the constructor */
    thr_constructor_arch(t);
   
#ifdef ARCH_HAS_FPU
#  ifdef CONFIG_FPU_LAZY
    t->saved_fpu_context = NULL;
#  else
    t->saved_fpu_context = slab_alloc(fpu_context_slab,kmflags);
    if (!t->saved_fpu_context)
        return -1;
#  endif
#endif  
 
    t->kstack = frame_alloc(STACK_FRAMES, FRAME_KA | kmflags);
    if (! t->kstack) {
#ifdef ARCH_HAS_FPU
        if (t->saved_fpu_context)
            slab_free(fpu_context_slab,t->saved_fpu_context);
#endif
        return -1;
    }
 
    return 0;
}
 
/** Destruction of thread_t object */
static int thr_destructor(void *obj)
{
    thread_t *t = (thread_t *) obj;
 
    /* call the architecture-specific part of the destructor */
    thr_destructor_arch(t);
 
    frame_free(KA2PA(t->kstack));
#ifdef ARCH_HAS_FPU
    if (t->saved_fpu_context)
        slab_free(fpu_context_slab,t->saved_fpu_context);
#endif
    return 1; /* One page freed */
}
 
/** Initialize threads
 *
 * Initialize kernel threads support.
 *
 */
void thread_init(void)
{
    THREAD = NULL;
    atomic_set(&nrdy,0);
    thread_slab = slab_cache_create("thread_slab",
                    sizeof(thread_t),0,
                    thr_constructor, thr_destructor, 0);
#ifdef ARCH_HAS_FPU
    fpu_context_slab = slab_cache_create("fpu_slab",
                         sizeof(fpu_context_t),
                         FPU_CONTEXT_ALIGN,
                         NULL, NULL, 0);
#endif
 
    btree_create(&threads_btree);
}
 
/** Make thread ready
 *
 * Switch thread t to the ready state.
 *
 * @param t Thread to make ready.
 *
 */
void thread_ready(thread_t *t)
{
    cpu_t *cpu;
    runq_t *r;
    ipl_t ipl;
    int i, avg;
 
    ipl = interrupts_disable();
 
    spinlock_lock(&t->lock);
 
    ASSERT(! (t->state == Ready));
 
    i = (t->priority < RQ_COUNT -1) ? ++t->priority : t->priority;
   
    cpu = CPU;
    if (t->flags & THREAD_FLAG_WIRED) {
        cpu = t->cpu;
    }
    t->state = Ready;
    spinlock_unlock(&t->lock);
   
    /*
     * Append t to respective ready queue on respective processor.
     */
    r = &cpu->rq[i];
    spinlock_lock(&r->lock);
    list_append(&t->rq_link, &r->rq_head);
    r->n++;
    spinlock_unlock(&r->lock);
 
    atomic_inc(&nrdy);
    avg = atomic_get(&nrdy) / config.cpu_active;
    atomic_inc(&cpu->nrdy);
 
    interrupts_restore(ipl);
}
 
/** Destroy thread memory structure
 *
 * Detach thread from all queues, cpus etc. and destroy it.
 *
 * Assume thread->lock is held!!
 */
void thread_destroy(thread_t *t)
{
    bool destroy_task = false; 
 
    ASSERT(t->state == Exiting || t->state == Undead);
    ASSERT(t->task);
    ASSERT(t->cpu);
 
    spinlock_lock(&t->cpu->lock);
    if(t->cpu->fpu_owner==t)
        t->cpu->fpu_owner=NULL;
    spinlock_unlock(&t->cpu->lock);
 
    spinlock_unlock(&t->lock);
 
    spinlock_lock(&threads_lock);
    btree_remove(&threads_btree, (btree_key_t) ((uintptr_t ) t), NULL);
    spinlock_unlock(&threads_lock);
 
    /*
     * Detach from the containing task.
     */
    spinlock_lock(&t->task->lock);
    list_remove(&t->th_link);
    if (--t->task->refcount == 0) {
        t->task->accept_new_threads = false;
        destroy_task = true;
    }
    spinlock_unlock(&t->task->lock);   
   
    if (destroy_task)
        task_destroy(t->task);
   
    slab_free(thread_slab, t);
}
 
/** Create new thread
 *
 * Create a new thread.
 *
 * @param func      Thread's implementing function.
 * @param arg       Thread's implementing function argument.
 * @param task      Task to which the thread belongs.
 * @param flags     Thread flags.
 * @param name      Symbolic name.
 * @param uncounted Thread's accounting doesn't affect accumulated task accounting.
 *
 * @return New thread's structure on success, NULL on failure.
 *
 */
thread_t *thread_create(void (* func)(void *), void *arg, task_t *task, int flags, char *name, bool uncounted)
{
    thread_t *t;
    ipl_t ipl;
   
    t = (thread_t *) slab_alloc(thread_slab, 0);
    if (!t)
        return NULL;
   
    /* Not needed, but good for debugging */
    memsetb((uintptr_t) t->kstack, THREAD_STACK_SIZE * 1 << STACK_FRAMES, 0);
   
    ipl = interrupts_disable();
    spinlock_lock(&tidlock);
    t->tid = ++last_tid;
    spinlock_unlock(&tidlock);
    interrupts_restore(ipl);
   
    context_save(&t->saved_context);
    context_set(&t->saved_context, FADDR(cushion), (uintptr_t) t->kstack, THREAD_STACK_SIZE);
   
    the_initialize((the_t *) t->kstack);
   
    ipl = interrupts_disable();
    t->saved_context.ipl = interrupts_read();
    interrupts_restore(ipl);
   
    memcpy(t->name, name, THREAD_NAME_BUFLEN);
   
    t->thread_code = func;
    t->thread_arg = arg;
    t->ticks = -1;
    t->cycles = 0;
    t->uncounted = uncounted;
    t->priority = -1;       /* start in rq[0] */
    t->cpu = NULL;
    t->flags = flags;
    t->state = Entering;
    t->call_me = NULL;
    t->call_me_with = NULL;
   
    timeout_initialize(&t->sleep_timeout);
    t->sleep_interruptible = false;
    t->sleep_queue = NULL;
    t->timeout_pending = 0;
 
    t->in_copy_from_uspace = false;
    t->in_copy_to_uspace = false;
 
    t->interrupted = false;
    t->join_type = None;
    t->detached = false;
    waitq_initialize(&t->join_wq);
   
    t->rwlock_holder_type = RWLOCK_NONE;
       
    t->task = task;
   
    t->fpu_context_exists = 0;
    t->fpu_context_engaged = 0;
 
    thread_create_arch(t);      /* might depend on previous initialization */
   
    /*
     * Attach to the containing task.
     */
    ipl = interrupts_disable();  
    spinlock_lock(&task->lock);
    if (!task->accept_new_threads) {
        spinlock_unlock(&task->lock);
        slab_free(thread_slab, t);
        interrupts_restore(ipl);
        return NULL;
    }
    list_append(&t->th_link, &task->th_head);
    if (task->refcount++ == 0)
        task->main_thread = t;
    spinlock_unlock(&task->lock);
 
    /*
     * Register this thread in the system-wide list.
     */
    spinlock_lock(&threads_lock);
    btree_insert(&threads_btree, (btree_key_t) ((uintptr_t) t), (void *) t, NULL);
    spinlock_unlock(&threads_lock);
   
    interrupts_restore(ipl);
   
    return t;
}
 
/** Terminate thread.
 *
 * End current thread execution and switch it to the exiting
 * state. All pending timeouts are executed.
 *
 */
void thread_exit(void)
{
    ipl_t ipl;
 
restart:
    ipl = interrupts_disable();
    spinlock_lock(&THREAD->lock);
    if (THREAD->timeout_pending) { /* busy waiting for timeouts in progress */
        spinlock_unlock(&THREAD->lock);
        interrupts_restore(ipl);
        goto restart;
    }
    THREAD->state = Exiting;
    spinlock_unlock(&THREAD->lock);
    scheduler();
 
    /* Not reached */
    while (1)
        ;
}
 
 
/** Thread sleep
 *
 * Suspend execution of the current thread.
 *
 * @param sec Number of seconds to sleep.
 *
 */
void thread_sleep(uint32_t sec)
{
    thread_usleep(sec*1000000);
}
 
/** Wait for another thread to exit.
 *
 * @param t Thread to join on exit.
 * @param usec Timeout in microseconds.
 * @param flags Mode of operation.
 *
 * @return An error code from errno.h or an error code from synch.h.
 */
int thread_join_timeout(thread_t *t, uint32_t usec, int flags)
{
    ipl_t ipl;
    int rc;
 
    if (t == THREAD)
        return EINVAL;
 
    /*
     * Since thread join can only be called once on an undetached thread,
     * the thread pointer is guaranteed to be still valid.
     */
   
    ipl = interrupts_disable();
    spinlock_lock(&t->lock);
    ASSERT(!t->detached);
    spinlock_unlock(&t->lock);
    interrupts_restore(ipl);
   
    rc = waitq_sleep_timeout(&t->join_wq, usec, flags);
   
    return rc; 
}
 
/** Detach thread.
 *
 * Mark the thread as detached, if the thread is already in the Undead state,
 * deallocate its resources.
 *
 * @param t Thread to be detached.
 */
void thread_detach(thread_t *t)
{
    ipl_t ipl;
 
    /*
     * Since the thread is expected to not be already detached,
     * pointer to it must be still valid.
     */
    ipl = interrupts_disable();
    spinlock_lock(&t->lock);
    ASSERT(!t->detached);
    if (t->state == Undead) {
        thread_destroy(t);  /* unlocks &t->lock */
        interrupts_restore(ipl);
        return;
    } else {
        t->detached = true;
    }
    spinlock_unlock(&t->lock);
    interrupts_restore(ipl);
}
 
/** Thread usleep
 *
 * Suspend execution of the current thread.
 *
 * @param usec Number of microseconds to sleep.
 *
 */
void thread_usleep(uint32_t usec)
{
    waitq_t wq;
                 
    waitq_initialize(&wq);
 
    (void) waitq_sleep_timeout(&wq, usec, SYNCH_FLAGS_NON_BLOCKING);
}
 
/** Register thread out-of-context invocation
 *
 * Register a function and its argument to be executed
 * on next context switch to the current thread.
 *
 * @param call_me      Out-of-context function.
 * @param call_me_with Out-of-context function argument.
 *
 */
void thread_register_call_me(void (* call_me)(void *), void *call_me_with)
{
    ipl_t ipl;
   
    ipl = interrupts_disable();
    spinlock_lock(&THREAD->lock);
    THREAD->call_me = call_me;
    THREAD->call_me_with = call_me_with;
    spinlock_unlock(&THREAD->lock);
    interrupts_restore(ipl);
}
 
/** Print list of threads debug info */
void thread_print_list(void)
{
    link_t *cur;
    ipl_t ipl;
   
    /* Messing with thread structures, avoid deadlock */
    ipl = interrupts_disable();
    spinlock_lock(&threads_lock);
   
    printf("tid    name       address    state    task       ctx code       stack      cycles     cpu  kstack     waitqueue\n");
    printf("------ ---------- ---------- -------- ---------- --- ---------- ---------- ---------- ---- ---------- ----------\n");
 
    for (cur = threads_btree.leaf_head.next; cur != &threads_btree.leaf_head; cur = cur->next) {
        btree_node_t *node;
        int i;
 
        node = list_get_instance(cur, btree_node_t, leaf_link);
        for (i = 0; i < node->keys; i++) {
            thread_t *t;
       
            t = (thread_t *) node->value[i];
           
            uint64_t cycles;
            char suffix;
 
 
 
 
 
 
 
 
            order(t->cycles, &cycles, &suffix);
 
 
 
 
 
           
            printf("%-6zd %-10s %#10zx %-8s %#10zx %-3ld %#10zx %#10zx %9llu%c ", t->tid, t->name, t, thread_states[t->state], t->task, t->task->context, t->thread_code, t->kstack, cycles, suffix);
           
            if (t->cpu)
                printf("%-4zd", t->cpu->id);
            else
                printf("none");
           
            if (t->state == Sleeping)
                printf(" %#10zx %#10zx", t->kstack, t->sleep_queue);
           
            printf("\n");
        }
    }
 
    spinlock_unlock(&threads_lock);
    interrupts_restore(ipl);
}
 
/** Check whether thread exists.
 *
 * Note that threads_lock must be already held and
 * interrupts must be already disabled.
 *
 * @param t Pointer to thread.
 *
 * @return True if thread t is known to the system, false otherwise.
 */
bool thread_exists(thread_t *t)
{
    btree_node_t *leaf;
   
    return btree_search(&threads_btree, (btree_key_t) ((uintptr_t) t), &leaf) != NULL;
}
 
 
/** Update accounting of current thread.
 *
 * Note that thread_lock on THREAD must be already held and
 * interrupts must be already disabled.
 *
 */
void thread_update_accounting(void)
{
    uint64_t time = get_cycle();
    THREAD->cycles += time - THREAD->last_cycle;
    THREAD->last_cycle = time;
}
 
/** Process syscall to create new thread.
 *
 */
unative_t sys_thread_create(uspace_arg_t *uspace_uarg, char *uspace_name)
{
    thread_t *t;
    char namebuf[THREAD_NAME_BUFLEN];
    uspace_arg_t *kernel_uarg;
    uint32_t tid;
    int rc;
 
    rc = copy_from_uspace(namebuf, uspace_name, THREAD_NAME_BUFLEN);
    if (rc != 0)
        return (unative_t) rc;
 
    kernel_uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t), 0);
    rc = copy_from_uspace(kernel_uarg, uspace_uarg, sizeof(uspace_arg_t));
    if (rc != 0) {
        free(kernel_uarg);
        return (unative_t) rc;
    }
 
    if ((t = thread_create(uinit, kernel_uarg, TASK, THREAD_FLAG_USPACE, namebuf, false))) {
        tid = t->tid;
        thread_ready(t);
        return (unative_t) tid;
    } else {
        free(kernel_uarg);
    }
 
    return (unative_t) ENOMEM;
}
 
/** Process syscall to terminate thread.
 *
 */
unative_t sys_thread_exit(int uspace_status)
{
    thread_exit();
    /* Unreachable */
    return 0;
}
 
/** @}
 */
 

Rev 2042	Rev 2050
1	/*	1	/*
2	* Copyright (C) 2001-2004 Jakub Jermar	2	* Copyright (C) 2001-2004 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup genericproc	29	/** @addtogroup genericproc
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file	34	* @file
35	* @brief Thread management functions.	35	* @brief Thread management functions.
36	*/	36	*/
37		37
38	#include <proc/scheduler.h>	38	#include <proc/scheduler.h>
39	#include <proc/thread.h>	39	#include <proc/thread.h>
40	#include <proc/task.h>	40	#include <proc/task.h>
41	#include <proc/uarg.h>	41	#include <proc/uarg.h>
42	#include <mm/frame.h>	42	#include <mm/frame.h>
43	#include <mm/page.h>	43	#include <mm/page.h>
44	#include <arch/asm.h>	44	#include <arch/asm.h>
45	#include <arch/cycle.h>	45	#include <arch/cycle.h>
46	#include <arch.h>	46	#include <arch.h>
47	#include <synch/synch.h>	47	#include <synch/synch.h>
48	#include <synch/spinlock.h>	48	#include <synch/spinlock.h>
49	#include <synch/waitq.h>	49	#include <synch/waitq.h>
50	#include <synch/rwlock.h>	50	#include <synch/rwlock.h>
51	#include <cpu.h>	51	#include <cpu.h>
52	#include <func.h>	52	#include <func.h>
53	#include <context.h>	53	#include <context.h>
54	#include <adt/btree.h>	54	#include <adt/btree.h>
55	#include <adt/list.h>	55	#include <adt/list.h>
56	#include <typedefs.h>	56	#include <typedefs.h>
57	#include <time/clock.h>	57	#include <time/clock.h>
58	#include <config.h>	58	#include <config.h>
59	#include <arch/interrupt.h>	59	#include <arch/interrupt.h>
60	#include <smp/ipi.h>	60	#include <smp/ipi.h>
61	#include <arch/faddr.h>	61	#include <arch/faddr.h>
62	#include <atomic.h>	62	#include <atomic.h>
63	#include <memstr.h>	63	#include <memstr.h>
64	#include <print.h>	64	#include <print.h>
65	#include <mm/slab.h>	65	#include <mm/slab.h>
66	#include <debug.h>	66	#include <debug.h>
67	#include <main/uinit.h>	67	#include <main/uinit.h>
68	#include <syscall/copy.h>	68	#include <syscall/copy.h>
69	#include <errno.h>	69	#include <errno.h>
70		70
71		71
72	/** Thread states */	72	/** Thread states */
73	char *thread_states[] = {	73	char *thread_states[] = {
74	"Invalid",	74	"Invalid",
75	"Running",	75	"Running",
76	"Sleeping",	76	"Sleeping",
77	"Ready",	77	"Ready",
78	"Entering",	78	"Entering",
79	"Exiting",	79	"Exiting",
80	"Undead"	80	"Undead"
81	};	81	};
82		82
83	/** Lock protecting the threads_btree B+tree. For locking rules, see declaration thereof. */	83	/** Lock protecting the threads_btree B+tree. For locking rules, see declaration thereof. */
84	SPINLOCK_INITIALIZE(threads_lock);	84	SPINLOCK_INITIALIZE(threads_lock);
85		85
86	/** B+tree of all threads.	86	/** B+tree of all threads.
87	*	87	*
88	* When a thread is found in the threads_btree B+tree, it is guaranteed to exist as long	88	* When a thread is found in the threads_btree B+tree, it is guaranteed to exist as long
89	* as the threads_lock is held.	89	* as the threads_lock is held.
90	*/	90	*/
91	btree_t threads_btree;	91	btree_t threads_btree;
92		92
93	SPINLOCK_INITIALIZE(tidlock);	93	SPINLOCK_INITIALIZE(tidlock);
94	uint32_t last_tid = 0;	94	uint32_t last_tid = 0;
95		95
96	static slab_cache_t *thread_slab;	96	static slab_cache_t *thread_slab;
97	#ifdef ARCH_HAS_FPU	97	#ifdef ARCH_HAS_FPU
98	slab_cache_t *fpu_context_slab;	98	slab_cache_t *fpu_context_slab;
99	#endif	99	#endif
100		100
101	/** Thread wrapper	101	/** Thread wrapper
102	*	102	*
103	* This wrapper is provided to ensure that every thread	103	* This wrapper is provided to ensure that every thread
104	* makes a call to thread_exit() when its implementing	104	* makes a call to thread_exit() when its implementing
105	* function returns.	105	* function returns.
106	*	106	*
107	* interrupts_disable() is assumed.	107	* interrupts_disable() is assumed.
108	*	108	*
109	*/	109	*/
110	static void cushion(void)	110	static void cushion(void)
111	{	111	{
112	void (f)(void ) = THREAD->thread_code;	112	void (f)(void ) = THREAD->thread_code;
113	void *arg = THREAD->thread_arg;	113	void *arg = THREAD->thread_arg;
114	THREAD->last_cycle = get_cycle();	114	THREAD->last_cycle = get_cycle();
115		115
116	/* This is where each thread wakes up after its creation */	116	/* This is where each thread wakes up after its creation */
117	spinlock_unlock(&THREAD->lock);	117	spinlock_unlock(&THREAD->lock);
118	interrupts_enable();	118	interrupts_enable();
119		119
120	f(arg);	120	f(arg);
121		121
122	/* Accumulate accounting to the task */	122	/* Accumulate accounting to the task */
123	ipl_t ipl = interrupts_disable();	123	ipl_t ipl = interrupts_disable();
124		124
125	spinlock_lock(&THREAD->lock);	125	spinlock_lock(&THREAD->lock);
126	if (!THREAD->uncounted) {	126	if (!THREAD->uncounted) {
127	thread_update_accounting();	127	thread_update_accounting();
128	uint64_t cycles = THREAD->cycles;	128	uint64_t cycles = THREAD->cycles;
129	THREAD->cycles = 0;	129	THREAD->cycles = 0;
130	spinlock_unlock(&THREAD->lock);	130	spinlock_unlock(&THREAD->lock);
131		131
132	spinlock_lock(&TASK->lock);	132	spinlock_lock(&TASK->lock);
133	TASK->cycles += cycles;	133	TASK->cycles += cycles;
134	spinlock_unlock(&TASK->lock);	134	spinlock_unlock(&TASK->lock);
135	} else	135	} else
136	spinlock_unlock(&THREAD->lock);	136	spinlock_unlock(&THREAD->lock);
137		137
138	interrupts_restore(ipl);	138	interrupts_restore(ipl);
139		139
140	thread_exit();	140	thread_exit();
141	/* not reached */	141	/* not reached */
142	}	142	}
143		143
144	/** Initialization and allocation for thread_t structure */	144	/** Initialization and allocation for thread_t structure */
145	static int thr_constructor(void *obj, int kmflags)	145	static int thr_constructor(void *obj, int kmflags)
146	{	146	{
147	thread_t t = (thread_t ) obj;	147	thread_t t = (thread_t ) obj;
148		148
149	spinlock_initialize(&t->lock, "thread_t_lock");	149	spinlock_initialize(&t->lock, "thread_t_lock");
150	link_initialize(&t->rq_link);	150	link_initialize(&t->rq_link);
151	link_initialize(&t->wq_link);	151	link_initialize(&t->wq_link);
152	link_initialize(&t->th_link);	152	link_initialize(&t->th_link);
153		153
154	/* call the architecture-specific part of the constructor */	154	/* call the architecture-specific part of the constructor */
155	thr_constructor_arch(t);	155	thr_constructor_arch(t);
156		156
157	#ifdef ARCH_HAS_FPU	157	#ifdef ARCH_HAS_FPU
158	# ifdef CONFIG_FPU_LAZY	158	# ifdef CONFIG_FPU_LAZY
159	t->saved_fpu_context = NULL;	159	t->saved_fpu_context = NULL;
160	# else	160	# else
161	t->saved_fpu_context = slab_alloc(fpu_context_slab,kmflags);	161	t->saved_fpu_context = slab_alloc(fpu_context_slab,kmflags);
162	if (!t->saved_fpu_context)	162	if (!t->saved_fpu_context)
163	return -1;	163	return -1;
164	# endif	164	# endif
165	#endif	165	#endif
166		166
167	t->kstack = frame_alloc(STACK_FRAMES, FRAME_KA \| kmflags);	167	t->kstack = frame_alloc(STACK_FRAMES, FRAME_KA \| kmflags);
168	if (! t->kstack) {	168	if (! t->kstack) {
169	#ifdef ARCH_HAS_FPU	169	#ifdef ARCH_HAS_FPU
170	if (t->saved_fpu_context)	170	if (t->saved_fpu_context)
171	slab_free(fpu_context_slab,t->saved_fpu_context);	171	slab_free(fpu_context_slab,t->saved_fpu_context);
172	#endif	172	#endif
173	return -1;	173	return -1;
174	}	174	}
175		175
176	return 0;	176	return 0;
177	}	177	}
178		178
179	/** Destruction of thread_t object */	179	/** Destruction of thread_t object */
180	static int thr_destructor(void *obj)	180	static int thr_destructor(void *obj)
181	{	181	{
182	thread_t t = (thread_t ) obj;	182	thread_t t = (thread_t ) obj;
183		183
184	/* call the architecture-specific part of the destructor */	184	/* call the architecture-specific part of the destructor */
185	thr_destructor_arch(t);	185	thr_destructor_arch(t);
186		186
187	frame_free(KA2PA(t->kstack));	187	frame_free(KA2PA(t->kstack));
188	#ifdef ARCH_HAS_FPU	188	#ifdef ARCH_HAS_FPU
189	if (t->saved_fpu_context)	189	if (t->saved_fpu_context)
190	slab_free(fpu_context_slab,t->saved_fpu_context);	190	slab_free(fpu_context_slab,t->saved_fpu_context);
191	#endif	191	#endif
192	return 1; /* One page freed */	192	return 1; /* One page freed */
193	}	193	}
194		194
195	/** Initialize threads	195	/** Initialize threads
196	*	196	*
197	* Initialize kernel threads support.	197	* Initialize kernel threads support.
198	*	198	*
199	*/	199	*/
200	void thread_init(void)	200	void thread_init(void)
201	{	201	{
202	THREAD = NULL;	202	THREAD = NULL;
203	atomic_set(&nrdy,0);	203	atomic_set(&nrdy,0);
204	thread_slab = slab_cache_create("thread_slab",	204	thread_slab = slab_cache_create("thread_slab",
205	sizeof(thread_t),0,	205	sizeof(thread_t),0,
206	thr_constructor, thr_destructor, 0);	206	thr_constructor, thr_destructor, 0);
207	#ifdef ARCH_HAS_FPU	207	#ifdef ARCH_HAS_FPU
208	fpu_context_slab = slab_cache_create("fpu_slab",	208	fpu_context_slab = slab_cache_create("fpu_slab",
209	sizeof(fpu_context_t),	209	sizeof(fpu_context_t),
210	FPU_CONTEXT_ALIGN,	210	FPU_CONTEXT_ALIGN,
211	NULL, NULL, 0);	211	NULL, NULL, 0);
212	#endif	212	#endif
213		213
214	btree_create(&threads_btree);	214	btree_create(&threads_btree);
215	}	215	}
216		216
217	/** Make thread ready	217	/** Make thread ready
218	*	218	*
219	* Switch thread t to the ready state.	219	* Switch thread t to the ready state.
220	*	220	*
221	* @param t Thread to make ready.	221	* @param t Thread to make ready.
222	*	222	*
223	*/	223	*/
224	void thread_ready(thread_t *t)	224	void thread_ready(thread_t *t)
225	{	225	{
226	cpu_t *cpu;	226	cpu_t *cpu;
227	runq_t *r;	227	runq_t *r;
228	ipl_t ipl;	228	ipl_t ipl;
229	int i, avg;	229	int i, avg;
230		230
231	ipl = interrupts_disable();	231	ipl = interrupts_disable();
232		232
233	spinlock_lock(&t->lock);	233	spinlock_lock(&t->lock);
234		234
235	ASSERT(! (t->state == Ready));	235	ASSERT(! (t->state == Ready));
236		236
237	i = (t->priority < RQ_COUNT -1) ? ++t->priority : t->priority;	237	i = (t->priority < RQ_COUNT -1) ? ++t->priority : t->priority;
238		238
239	cpu = CPU;	239	cpu = CPU;
240	if (t->flags & THREAD_FLAG_WIRED) {	240	if (t->flags & THREAD_FLAG_WIRED) {
241	cpu = t->cpu;	241	cpu = t->cpu;
242	}	242	}
243	t->state = Ready;	243	t->state = Ready;
244	spinlock_unlock(&t->lock);	244	spinlock_unlock(&t->lock);
245		245
246	/*	246	/*
247	* Append t to respective ready queue on respective processor.	247	* Append t to respective ready queue on respective processor.
248	*/	248	*/
249	r = &cpu->rq[i];	249	r = &cpu->rq[i];
250	spinlock_lock(&r->lock);	250	spinlock_lock(&r->lock);
251	list_append(&t->rq_link, &r->rq_head);	251	list_append(&t->rq_link, &r->rq_head);
252	r->n++;	252	r->n++;
253	spinlock_unlock(&r->lock);	253	spinlock_unlock(&r->lock);
254		254
255	atomic_inc(&nrdy);	255	atomic_inc(&nrdy);
256	avg = atomic_get(&nrdy) / config.cpu_active;	256	avg = atomic_get(&nrdy) / config.cpu_active;
257	atomic_inc(&cpu->nrdy);	257	atomic_inc(&cpu->nrdy);
258		258
259	interrupts_restore(ipl);	259	interrupts_restore(ipl);
260	}	260	}
261		261
262	/** Destroy thread memory structure	262	/** Destroy thread memory structure
263	*	263	*
264	* Detach thread from all queues, cpus etc. and destroy it.	264	* Detach thread from all queues, cpus etc. and destroy it.
265	*	265	*
266	* Assume thread->lock is held!!	266	* Assume thread->lock is held!!
267	*/	267	*/
268	void thread_destroy(thread_t *t)	268	void thread_destroy(thread_t *t)
269	{	269	{
270	bool destroy_task = false;	270	bool destroy_task = false;
271		271
272	ASSERT(t->state == Exiting \|\| t->state == Undead);	272	ASSERT(t->state == Exiting \|\| t->state == Undead);
273	ASSERT(t->task);	273	ASSERT(t->task);
274	ASSERT(t->cpu);	274	ASSERT(t->cpu);
275		275
276	spinlock_lock(&t->cpu->lock);	276	spinlock_lock(&t->cpu->lock);
277	if(t->cpu->fpu_owner==t)	277	if(t->cpu->fpu_owner==t)
278	t->cpu->fpu_owner=NULL;	278	t->cpu->fpu_owner=NULL;
279	spinlock_unlock(&t->cpu->lock);	279	spinlock_unlock(&t->cpu->lock);
280		280
281	spinlock_unlock(&t->lock);	281	spinlock_unlock(&t->lock);
282		282
283	spinlock_lock(&threads_lock);	283	spinlock_lock(&threads_lock);
284	btree_remove(&threads_btree, (btree_key_t) ((uintptr_t ) t), NULL);	284	btree_remove(&threads_btree, (btree_key_t) ((uintptr_t ) t), NULL);
285	spinlock_unlock(&threads_lock);	285	spinlock_unlock(&threads_lock);
286		286
287	/*	287	/*
288	* Detach from the containing task.	288	* Detach from the containing task.
289	*/	289	*/
290	spinlock_lock(&t->task->lock);	290	spinlock_lock(&t->task->lock);
291	list_remove(&t->th_link);	291	list_remove(&t->th_link);
292	if (--t->task->refcount == 0) {	292	if (--t->task->refcount == 0) {
293	t->task->accept_new_threads = false;	293	t->task->accept_new_threads = false;
294	destroy_task = true;	294	destroy_task = true;
295	}	295	}
296	spinlock_unlock(&t->task->lock);	296	spinlock_unlock(&t->task->lock);
297		297
298	if (destroy_task)	298	if (destroy_task)
299	task_destroy(t->task);	299	task_destroy(t->task);
300		300
301	slab_free(thread_slab, t);	301	slab_free(thread_slab, t);
302	}	302	}
303		303
304	/** Create new thread	304	/** Create new thread
305	*	305	*
306	* Create a new thread.	306	* Create a new thread.
307	*	307	*
308	* @param func Thread's implementing function.	308	* @param func Thread's implementing function.
309	* @param arg Thread's implementing function argument.	309	* @param arg Thread's implementing function argument.
310	* @param task Task to which the thread belongs.	310	* @param task Task to which the thread belongs.
311	* @param flags Thread flags.	311	* @param flags Thread flags.
312	* @param name Symbolic name.	312	* @param name Symbolic name.
313	* @param uncounted Thread's accounting doesn't affect accumulated task accounting.	313	* @param uncounted Thread's accounting doesn't affect accumulated task accounting.
314	*	314	*
315	* @return New thread's structure on success, NULL on failure.	315	* @return New thread's structure on success, NULL on failure.
316	*	316	*
317	*/	317	*/
318	thread_t thread_create(void ( func)(void ), void arg, task_t task, int flags, char name, bool uncounted)	318	thread_t thread_create(void ( func)(void ), void arg, task_t task, int flags, char name, bool uncounted)
319	{	319	{
320	thread_t *t;	320	thread_t *t;
321	ipl_t ipl;	321	ipl_t ipl;
322		322
323	t = (thread_t *) slab_alloc(thread_slab, 0);	323	t = (thread_t *) slab_alloc(thread_slab, 0);
324	if (!t)	324	if (!t)
325	return NULL;	325	return NULL;
326		326
327	/* Not needed, but good for debugging */	327	/* Not needed, but good for debugging */
328	memsetb((uintptr_t) t->kstack, THREAD_STACK_SIZE * 1 << STACK_FRAMES, 0);	328	memsetb((uintptr_t) t->kstack, THREAD_STACK_SIZE * 1 << STACK_FRAMES, 0);
329		329
330	ipl = interrupts_disable();	330	ipl = interrupts_disable();
331	spinlock_lock(&tidlock);	331	spinlock_lock(&tidlock);
332	t->tid = ++last_tid;	332	t->tid = ++last_tid;
333	spinlock_unlock(&tidlock);	333	spinlock_unlock(&tidlock);
334	interrupts_restore(ipl);	334	interrupts_restore(ipl);
335		335
336	context_save(&t->saved_context);	336	context_save(&t->saved_context);
337	context_set(&t->saved_context, FADDR(cushion), (uintptr_t) t->kstack, THREAD_STACK_SIZE);	337	context_set(&t->saved_context, FADDR(cushion), (uintptr_t) t->kstack, THREAD_STACK_SIZE);
338		338
339	the_initialize((the_t *) t->kstack);	339	the_initialize((the_t *) t->kstack);
340		340
341	ipl = interrupts_disable();	341	ipl = interrupts_disable();
342	t->saved_context.ipl = interrupts_read();	342	t->saved_context.ipl = interrupts_read();
343	interrupts_restore(ipl);	343	interrupts_restore(ipl);
344		344
345	memcpy(t->name, name, THREAD_NAME_BUFLEN);	345	memcpy(t->name, name, THREAD_NAME_BUFLEN);
346		346
347	t->thread_code = func;	347	t->thread_code = func;
348	t->thread_arg = arg;	348	t->thread_arg = arg;
349	t->ticks = -1;	349	t->ticks = -1;
350	t->cycles = 0;	350	t->cycles = 0;
351	t->uncounted = uncounted;	351	t->uncounted = uncounted;
352	t->priority = -1; /* start in rq[0] */	352	t->priority = -1; /* start in rq[0] */
353	t->cpu = NULL;	353	t->cpu = NULL;
354	t->flags = flags;	354	t->flags = flags;
355	t->state = Entering;	355	t->state = Entering;
356	t->call_me = NULL;	356	t->call_me = NULL;
357	t->call_me_with = NULL;	357	t->call_me_with = NULL;
358		358
359	timeout_initialize(&t->sleep_timeout);	359	timeout_initialize(&t->sleep_timeout);
360	t->sleep_interruptible = false;	360	t->sleep_interruptible = false;
361	t->sleep_queue = NULL;	361	t->sleep_queue = NULL;
362	t->timeout_pending = 0;	362	t->timeout_pending = 0;
363		363
364	t->in_copy_from_uspace = false;	364	t->in_copy_from_uspace = false;
365	t->in_copy_to_uspace = false;	365	t->in_copy_to_uspace = false;
366		366
367	t->interrupted = false;	367	t->interrupted = false;
368	t->join_type = None;	368	t->join_type = None;
369	t->detached = false;	369	t->detached = false;
370	waitq_initialize(&t->join_wq);	370	waitq_initialize(&t->join_wq);
371		371
372	t->rwlock_holder_type = RWLOCK_NONE;	372	t->rwlock_holder_type = RWLOCK_NONE;
373		373
374	t->task = task;	374	t->task = task;
375		375
376	t->fpu_context_exists = 0;	376	t->fpu_context_exists = 0;
377	t->fpu_context_engaged = 0;	377	t->fpu_context_engaged = 0;
378		378
379	thread_create_arch(t); /* might depend on previous initialization */	379	thread_create_arch(t); /* might depend on previous initialization */
380		380
381	/*	381	/*
382	* Attach to the containing task.	382	* Attach to the containing task.
383	*/	383	*/
384	ipl = interrupts_disable();	384	ipl = interrupts_disable();
385	spinlock_lock(&task->lock);	385	spinlock_lock(&task->lock);
386	if (!task->accept_new_threads) {	386	if (!task->accept_new_threads) {
387	spinlock_unlock(&task->lock);	387	spinlock_unlock(&task->lock);
388	slab_free(thread_slab, t);	388	slab_free(thread_slab, t);
389	interrupts_restore(ipl);	389	interrupts_restore(ipl);
390	return NULL;	390	return NULL;
391	}	391	}
392	list_append(&t->th_link, &task->th_head);	392	list_append(&t->th_link, &task->th_head);
393	if (task->refcount++ == 0)	393	if (task->refcount++ == 0)
394	task->main_thread = t;	394	task->main_thread = t;
395	spinlock_unlock(&task->lock);	395	spinlock_unlock(&task->lock);
396		396
397	/*	397	/*
398	* Register this thread in the system-wide list.	398	* Register this thread in the system-wide list.
399	*/	399	*/
400	spinlock_lock(&threads_lock);	400	spinlock_lock(&threads_lock);
401	btree_insert(&threads_btree, (btree_key_t) ((uintptr_t) t), (void *) t, NULL);	401	btree_insert(&threads_btree, (btree_key_t) ((uintptr_t) t), (void *) t, NULL);
402	spinlock_unlock(&threads_lock);	402	spinlock_unlock(&threads_lock);
403		403
404	interrupts_restore(ipl);	404	interrupts_restore(ipl);
405		405
406	return t;	406	return t;
407	}	407	}
408		408
409	/** Terminate thread.	409	/** Terminate thread.
410	*	410	*
411	* End current thread execution and switch it to the exiting	411	* End current thread execution and switch it to the exiting
412	* state. All pending timeouts are executed.	412	* state. All pending timeouts are executed.
413	*	413	*
414	*/	414	*/
415	void thread_exit(void)	415	void thread_exit(void)
416	{	416	{
417	ipl_t ipl;	417	ipl_t ipl;
418		418
419	restart:	419	restart:
420	ipl = interrupts_disable();	420	ipl = interrupts_disable();
421	spinlock_lock(&THREAD->lock);	421	spinlock_lock(&THREAD->lock);
422	if (THREAD->timeout_pending) { /* busy waiting for timeouts in progress */	422	if (THREAD->timeout_pending) { /* busy waiting for timeouts in progress */
423	spinlock_unlock(&THREAD->lock);	423	spinlock_unlock(&THREAD->lock);
424	interrupts_restore(ipl);	424	interrupts_restore(ipl);
425	goto restart;	425	goto restart;
426	}	426	}
427	THREAD->state = Exiting;	427	THREAD->state = Exiting;
428	spinlock_unlock(&THREAD->lock);	428	spinlock_unlock(&THREAD->lock);
429	scheduler();	429	scheduler();
430		430
431	/* Not reached */	431	/* Not reached */
432	while (1)	432	while (1)
433	;	433	;
434	}	434	}
435		435
436		436
437	/** Thread sleep	437	/** Thread sleep
438	*	438	*
439	* Suspend execution of the current thread.	439	* Suspend execution of the current thread.
440	*	440	*
441	* @param sec Number of seconds to sleep.	441	* @param sec Number of seconds to sleep.
442	*	442	*
443	*/	443	*/
444	void thread_sleep(uint32_t sec)	444	void thread_sleep(uint32_t sec)
445	{	445	{
446	thread_usleep(sec*1000000);	446	thread_usleep(sec*1000000);
447	}	447	}
448		448
449	/** Wait for another thread to exit.	449	/** Wait for another thread to exit.
450	*	450	*
451	* @param t Thread to join on exit.	451	* @param t Thread to join on exit.
452	* @param usec Timeout in microseconds.	452	* @param usec Timeout in microseconds.
453	* @param flags Mode of operation.	453	* @param flags Mode of operation.
454	*	454	*
455	* @return An error code from errno.h or an error code from synch.h.	455	* @return An error code from errno.h or an error code from synch.h.
456	*/	456	*/
457	int thread_join_timeout(thread_t *t, uint32_t usec, int flags)	457	int thread_join_timeout(thread_t *t, uint32_t usec, int flags)
458	{	458	{
459	ipl_t ipl;	459	ipl_t ipl;
460	int rc;	460	int rc;
461		461
462	if (t == THREAD)	462	if (t == THREAD)
463	return EINVAL;	463	return EINVAL;
464		464
465	/*	465	/*
466	* Since thread join can only be called once on an undetached thread,	466	* Since thread join can only be called once on an undetached thread,
467	* the thread pointer is guaranteed to be still valid.	467	* the thread pointer is guaranteed to be still valid.
468	*/	468	*/
469		469
470	ipl = interrupts_disable();	470	ipl = interrupts_disable();
471	spinlock_lock(&t->lock);	471	spinlock_lock(&t->lock);
472	ASSERT(!t->detached);	472	ASSERT(!t->detached);
473	spinlock_unlock(&t->lock);	473	spinlock_unlock(&t->lock);
474	interrupts_restore(ipl);	474	interrupts_restore(ipl);
475		475
476	rc = waitq_sleep_timeout(&t->join_wq, usec, flags);	476	rc = waitq_sleep_timeout(&t->join_wq, usec, flags);
477		477
478	return rc;	478	return rc;
479	}	479	}
480		480
481	/** Detach thread.	481	/** Detach thread.
482	*	482	*
483	* Mark the thread as detached, if the thread is already in the Undead state,	483	* Mark the thread as detached, if the thread is already in the Undead state,
484	* deallocate its resources.	484	* deallocate its resources.
485	*	485	*
486	* @param t Thread to be detached.	486	* @param t Thread to be detached.
487	*/	487	*/
488	void thread_detach(thread_t *t)	488	void thread_detach(thread_t *t)
489	{	489	{
490	ipl_t ipl;	490	ipl_t ipl;
491		491
492	/*	492	/*
493	* Since the thread is expected to not be already detached,	493	* Since the thread is expected to not be already detached,
494	* pointer to it must be still valid.	494	* pointer to it must be still valid.
495	*/	495	*/
496	ipl = interrupts_disable();	496	ipl = interrupts_disable();
497	spinlock_lock(&t->lock);	497	spinlock_lock(&t->lock);
498	ASSERT(!t->detached);	498	ASSERT(!t->detached);
499	if (t->state == Undead) {	499	if (t->state == Undead) {
500	thread_destroy(t); /* unlocks &t->lock */	500	thread_destroy(t); /* unlocks &t->lock */

Subversion Repositories HelenOS

(root)/trunk/kernel/generic/src/proc/thread.c @ 2444 – Rev 2042 → 2050