0,0 → 1,499 |
/* |
* 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 Task management. |
*/ |
|
#include <main/uinit.h> |
#include <proc/thread.h> |
#include <proc/task.h> |
#include <proc/uarg.h> |
#include <mm/as.h> |
#include <mm/slab.h> |
#include <synch/spinlock.h> |
#include <arch.h> |
#include <panic.h> |
#include <adt/btree.h> |
#include <adt/list.h> |
#include <ipc/ipc.h> |
#include <security/cap.h> |
#include <memstr.h> |
#include <print.h> |
#include <elf.h> |
#include <errno.h> |
#include <syscall/copy.h> |
#include <console/klog.h> |
|
#ifndef LOADED_PROG_STACK_PAGES_NO |
#define LOADED_PROG_STACK_PAGES_NO 1 |
#endif |
|
/** Spinlock protecting the tasks_btree B+tree. */ |
SPINLOCK_INITIALIZE(tasks_lock); |
|
/** B+tree of active tasks. |
* |
* The task is guaranteed to exist after it was found in the tasks_btree as long as: |
* @li the tasks_lock is held, |
* @li the task's lock is held when task's lock is acquired before releasing tasks_lock or |
* @li the task's refcount is grater than 0 |
* |
*/ |
btree_t tasks_btree; |
|
static task_id_t task_counter = 0; |
|
static void ktaskclnp(void *arg); |
static void ktaskgc(void *arg); |
|
/** Initialize tasks |
* |
* Initialize kernel tasks support. |
* |
*/ |
void task_init(void) |
{ |
TASK = NULL; |
btree_create(&tasks_btree); |
} |
|
|
/** Create new task |
* |
* Create new task with no threads. |
* |
* @param as Task's address space. |
* @param name Symbolic name. |
* |
* @return New task's structure |
* |
*/ |
task_t *task_create(as_t *as, char *name) |
{ |
ipl_t ipl; |
task_t *ta; |
int i; |
|
ta = (task_t *) malloc(sizeof(task_t), 0); |
|
task_create_arch(ta); |
|
spinlock_initialize(&ta->lock, "task_ta_lock"); |
list_initialize(&ta->th_head); |
ta->as = as; |
ta->name = name; |
ta->main_thread = NULL; |
ta->refcount = 0; |
|
ta->capabilities = 0; |
ta->accept_new_threads = true; |
|
ipc_answerbox_init(&ta->answerbox); |
for (i=0; i < IPC_MAX_PHONES;i++) |
ipc_phone_init(&ta->phones[i]); |
if (ipc_phone_0) |
ipc_phone_connect(&ta->phones[0], ipc_phone_0); |
atomic_set(&ta->active_calls, 0); |
|
mutex_initialize(&ta->futexes_lock); |
btree_create(&ta->futexes); |
|
ipl = interrupts_disable(); |
|
/* |
* Increment address space reference count. |
* TODO: Reconsider the locking scheme. |
*/ |
mutex_lock(&as->lock); |
as->refcount++; |
mutex_unlock(&as->lock); |
|
spinlock_lock(&tasks_lock); |
|
ta->taskid = ++task_counter; |
btree_insert(&tasks_btree, (btree_key_t) ta->taskid, (void *) ta, NULL); |
|
spinlock_unlock(&tasks_lock); |
interrupts_restore(ipl); |
|
return ta; |
} |
|
/** Destroy task. |
* |
* @param t Task to be destroyed. |
*/ |
void task_destroy(task_t *t) |
{ |
task_destroy_arch(t); |
btree_destroy(&t->futexes); |
|
mutex_lock_active(&t->as->lock); |
if (--t->as->refcount == 0) { |
mutex_unlock(&t->as->lock); |
as_destroy(t->as); |
/* |
* t->as is destroyed. |
*/ |
} else { |
mutex_unlock(&t->as->lock); |
} |
|
free(t); |
TASK = NULL; |
} |
|
/** Create new task with 1 thread and run it |
* |
* @param program_addr Address of program executable image. |
* @param name Program name. |
* |
* @return Task of the running program or NULL on error. |
*/ |
task_t * task_run_program(void *program_addr, char *name) |
{ |
as_t *as; |
as_area_t *a; |
int rc; |
thread_t *t1, *t2; |
task_t *task; |
uspace_arg_t *kernel_uarg; |
|
as = as_create(0); |
ASSERT(as); |
|
rc = elf_load((elf_header_t *) program_addr, as); |
if (rc != EE_OK) { |
as_destroy(as); |
return NULL; |
} |
|
kernel_uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t), 0); |
kernel_uarg->uspace_entry = (void *) ((elf_header_t *) program_addr)->e_entry; |
kernel_uarg->uspace_stack = (void *) USTACK_ADDRESS; |
kernel_uarg->uspace_thread_function = NULL; |
kernel_uarg->uspace_thread_arg = NULL; |
kernel_uarg->uspace_uarg = NULL; |
|
task = task_create(as, name); |
ASSERT(task); |
|
/* |
* Create the data as_area. |
*/ |
a = as_area_create(as, AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE, |
LOADED_PROG_STACK_PAGES_NO*PAGE_SIZE, |
USTACK_ADDRESS, AS_AREA_ATTR_NONE, &anon_backend, NULL); |
|
/* |
* Create the main thread. |
*/ |
t1 = thread_create(uinit, kernel_uarg, task, 0, "uinit"); |
ASSERT(t1); |
|
/* |
* Create killer thread for the new task. |
*/ |
t2 = thread_create(ktaskgc, t1, task, 0, "ktaskgc"); |
ASSERT(t2); |
thread_ready(t2); |
|
thread_ready(t1); |
|
return task; |
} |
|
/** Syscall for reading task ID from userspace. |
* |
* @param uspace_task_id Userspace address of 8-byte buffer where to store current task ID. |
* |
* @return 0 on success or an error code from @ref errno.h. |
*/ |
unative_t sys_task_get_id(task_id_t *uspace_task_id) |
{ |
/* |
* No need to acquire lock on TASK because taskid |
* remains constant for the lifespan of the task. |
*/ |
return (unative_t) copy_to_uspace(uspace_task_id, &TASK->taskid, sizeof(TASK->taskid)); |
} |
|
/** Find task structure corresponding to task ID. |
* |
* The tasks_lock must be already held by the caller of this function |
* and interrupts must be disabled. |
* |
* @param id Task ID. |
* |
* @return Task structure address or NULL if there is no such task ID. |
*/ |
task_t *task_find_by_id(task_id_t id) |
{ |
btree_node_t *leaf; |
|
return (task_t *) btree_search(&tasks_btree, (btree_key_t) id, &leaf); |
} |
|
/** Kill task. |
* |
* @param id ID of the task to be killed. |
* |
* @return 0 on success or an error code from errno.h |
*/ |
int task_kill(task_id_t id) |
{ |
ipl_t ipl; |
task_t *ta; |
thread_t *t; |
link_t *cur; |
|
if (id == 1) |
return EPERM; |
|
ipl = interrupts_disable(); |
spinlock_lock(&tasks_lock); |
|
if (!(ta = task_find_by_id(id))) { |
spinlock_unlock(&tasks_lock); |
interrupts_restore(ipl); |
return ENOENT; |
} |
|
spinlock_lock(&ta->lock); |
ta->refcount++; |
spinlock_unlock(&ta->lock); |
|
btree_remove(&tasks_btree, ta->taskid, NULL); |
spinlock_unlock(&tasks_lock); |
|
t = thread_create(ktaskclnp, NULL, ta, 0, "ktaskclnp"); |
|
spinlock_lock(&ta->lock); |
ta->accept_new_threads = false; |
ta->refcount--; |
|
/* |
* Interrupt all threads except ktaskclnp. |
*/ |
for (cur = ta->th_head.next; cur != &ta->th_head; cur = cur->next) { |
thread_t *thr; |
bool sleeping = false; |
|
thr = list_get_instance(cur, thread_t, th_link); |
if (thr == t) |
continue; |
|
spinlock_lock(&thr->lock); |
thr->interrupted = true; |
if (thr->state == Sleeping) |
sleeping = true; |
spinlock_unlock(&thr->lock); |
|
if (sleeping) |
waitq_interrupt_sleep(thr); |
} |
|
spinlock_unlock(&ta->lock); |
interrupts_restore(ipl); |
|
if (t) |
thread_ready(t); |
|
return 0; |
} |
|
/** Print task list */ |
void task_print_list(void) |
{ |
link_t *cur; |
ipl_t ipl; |
|
/* Messing with thread structures, avoid deadlock */ |
ipl = interrupts_disable(); |
spinlock_lock(&tasks_lock); |
|
for (cur = tasks_btree.leaf_head.next; cur != &tasks_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++) { |
task_t *t; |
int j; |
|
t = (task_t *) node->value[i]; |
|
spinlock_lock(&t->lock); |
printf("%s(%lld): address=%#zx, as=%#zx, ActiveCalls: %zd", |
t->name, t->taskid, t, t->as, atomic_get(&t->active_calls)); |
for (j=0; j < IPC_MAX_PHONES; j++) { |
if (t->phones[j].callee) |
printf(" Ph(%zd): %#zx ", j, t->phones[j].callee); |
} |
printf("\n"); |
spinlock_unlock(&t->lock); |
} |
} |
|
spinlock_unlock(&tasks_lock); |
interrupts_restore(ipl); |
} |
|
/** Kernel thread used to cleanup the task after it is killed. */ |
void ktaskclnp(void *arg) |
{ |
ipl_t ipl; |
thread_t *t = NULL, *main_thread; |
link_t *cur; |
bool again; |
|
thread_detach(THREAD); |
|
loop: |
ipl = interrupts_disable(); |
spinlock_lock(&TASK->lock); |
|
main_thread = TASK->main_thread; |
|
/* |
* Find a thread to join. |
*/ |
again = false; |
for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) { |
t = list_get_instance(cur, thread_t, th_link); |
|
spinlock_lock(&t->lock); |
if (t == THREAD) { |
spinlock_unlock(&t->lock); |
continue; |
} else if (t == main_thread) { |
spinlock_unlock(&t->lock); |
continue; |
} else if (t->join_type != None) { |
spinlock_unlock(&t->lock); |
again = true; |
continue; |
} else { |
t->join_type = TaskClnp; |
spinlock_unlock(&t->lock); |
again = false; |
break; |
} |
} |
|
spinlock_unlock(&TASK->lock); |
interrupts_restore(ipl); |
|
if (again) { |
/* |
* Other cleanup (e.g. ktaskgc) is in progress. |
*/ |
scheduler(); |
goto loop; |
} |
|
if (t != THREAD) { |
ASSERT(t != main_thread); /* uninit is joined and detached in ktaskgc */ |
thread_join(t); |
thread_detach(t); |
goto loop; /* go for another thread */ |
} |
|
/* |
* Now there are no other threads in this task |
* and no new threads can be created. |
*/ |
|
ipc_cleanup(); |
futex_cleanup(); |
klog_printf("Cleanup of task %lld completed.", TASK->taskid); |
} |
|
/** Kernel thread used to kill the userspace task when its main thread exits. |
* |
* This thread waits until the main userspace thread (i.e. uninit) exits. |
* When this happens, the task is killed. In the meantime, exited threads |
* are garbage collected. |
* |
* @param arg Pointer to the thread structure of the task's main thread. |
*/ |
void ktaskgc(void *arg) |
{ |
thread_t *t = (thread_t *) arg; |
loop: |
/* |
* Userspace threads cannot detach themselves, |
* therefore the thread pointer is guaranteed to be valid. |
*/ |
if (thread_join_timeout(t, 1000000, SYNCH_FLAGS_NONE) == ESYNCH_TIMEOUT) { /* sleep uninterruptibly here! */ |
ipl_t ipl; |
link_t *cur; |
thread_t *thr = NULL; |
|
/* |
* The join timed out. Try to do some garbage collection of Undead threads. |
*/ |
more_gc: |
ipl = interrupts_disable(); |
spinlock_lock(&TASK->lock); |
|
for (cur = TASK->th_head.next; cur != &TASK->th_head; cur = cur->next) { |
thr = list_get_instance(cur, thread_t, th_link); |
spinlock_lock(&thr->lock); |
if (thr != t && thr->state == Undead && thr->join_type == None) { |
thr->join_type = TaskGC; |
spinlock_unlock(&thr->lock); |
break; |
} |
spinlock_unlock(&thr->lock); |
thr = NULL; |
} |
spinlock_unlock(&TASK->lock); |
interrupts_restore(ipl); |
|
if (thr) { |
thread_join(thr); |
thread_detach(thr); |
scheduler(); |
goto more_gc; |
} |
|
goto loop; |
} |
thread_detach(t); |
task_kill(TASK->taskid); |
} |
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/** @} |
*/ |