WebSVN – HelenOS-historic – Diff – /kernel/trunk/generic/src/proc/task.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.
  */
 /**
  * @file    task.c
  * @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>
 #ifndef LOADED_PROG_STACK_PAGES_NO
 #define LOADED_PROG_STACK_PAGES_NO 1
 #endif
 SPINLOCK_INITIALIZE(tasks_lock);
 btree_t tasks_btree;
 static task_id_t task_counter = 0;
+static void ktask_cleanup(void *);
 /** 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->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)
+{
+}
 /** 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 *t;
     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);
     t = thread_create(uinit, kernel_uarg, task, 0, "uinit");
     ASSERT(t);
     thread_ready(t);
     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.
  */
 __native 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 (__native) 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;
+    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);
+    t = thread_create(ktask_cleanup, NULL, ta, 0, "ktask_cleanup");
+    spinlock_lock(&ta->lock);
+    ta->refcount--;
+    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);
+    }
+    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. */
+void ktask_cleanup(void *arg)
+{
+    /*
+     * TODO:
+     * Wait until it is save to cleanup the task (i.e. all other threads exit)
+     * and do the cleanup (e.g. close IPC communication and release used futexes).
+     * When this thread exits, the task refcount drops to zero and the task structure is
+     * cleaned.
+     */
+}

Subversion Repositories HelenOS-historic

(root)/kernel/trunk/generic/src/proc/task.c @ 1757 – Rev 1573 → 1579