/**************************************************************************** * sched/task/task_create.c * * Copyright (C) 2007-2010, 2013-2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "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 * COPYRIGHT OWNER OR CONTRIBUTORS 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include "sched/sched.h" #include "group/group.h" #include "task/task.h" /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: thread_create * * Description: * This function creates and activates a new thread of the specified type * with a specified priority and returns its system-assigned ID. It is the * internal, common implementation of task_create() and kernel_thread(). * See comments with task_create() for further information. * * Input Parameters: * name - Name of the new task * ttype - Type of the new task * priority - Priority of the new task * stack_size - size (in bytes) of the stack needed * entry - Entry point of a new task * arg - A pointer to an array of input parameters. Up to * CONFIG_MAX_TASK_ARG parameters may be provided. If fewer * than CONFIG_MAX_TASK_ARG parameters are passed, the list * should be terminated with a NULL argv[] value. If no * parameters are required, argv may be NULL. * * Return Value: * Returns the non-zero process ID of the new task or ERROR if memory is * insufficient or the task cannot be created. The errno will be set to * indicate the nature of the error (always ENOMEM). * ****************************************************************************/ static int thread_create(FAR const char *name, uint8_t ttype, int priority, int stack_size, main_t entry, FAR char * const argv[]) { FAR struct task_tcb_s *tcb; pid_t pid; int errcode; int ret; /* Allocate a TCB for the new task. */ tcb = (FAR struct task_tcb_s *)kmm_zalloc(sizeof(struct task_tcb_s)); if (!tcb) { sdbg("ERROR: Failed to allocate TCB\n"); errcode = ENOMEM; goto errout; } /* Allocate a new task group with privileges appropriate for the parent * thread type. */ #ifdef HAVE_TASK_GROUP ret = group_allocate(tcb, ttype); if (ret < 0) { errcode = -ret; goto errout_with_tcb; } #endif /* Associate file descriptors with the new task */ #if CONFIG_NFILE_DESCRIPTORS > 0 || CONFIG_NSOCKET_DESCRIPTORS > 0 ret = group_setuptaskfiles(tcb); if (ret < OK) { errcode = -ret; goto errout_with_tcb; } #endif /* Allocate the stack for the TCB */ ret = up_create_stack((FAR struct tcb_s *)tcb, stack_size, ttype); if (ret < OK) { errcode = -ret; goto errout_with_tcb; } /* Initialize the task control block */ ret = task_schedsetup(tcb, priority, task_start, entry, ttype); if (ret < OK) { errcode = -ret; goto errout_with_tcb; } /* Setup to pass parameters to the new task */ (void)task_argsetup(tcb, name, argv); /* Now we have enough in place that we can join the group */ #ifdef HAVE_TASK_GROUP ret = group_initialize(tcb); if (ret < 0) { errcode = -ret; goto errout_with_tcb; } #endif /* Get the assigned pid before we start the task */ pid = (int)tcb->cmn.pid; /* Activate the task */ ret = task_activate((FAR struct tcb_s *)tcb); if (ret < OK) { errcode = get_errno(); /* The TCB was added to the active task list by task_schedsetup() */ dq_rem((FAR dq_entry_t *)tcb, (FAR dq_queue_t *)&g_inactivetasks); goto errout_with_tcb; } return pid; errout_with_tcb: sched_releasetcb((FAR struct tcb_s *)tcb, ttype); errout: set_errno(errcode); return ERROR; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: task_create * * Description: * This function creates and activates a new task with a specified * priority and returns its system-assigned ID. * * The entry address entry is the address of the "main" function of the * task. This function will be called once the C environment has been * set up. The specified function will be called with four arguments. * Should the specified routine return, a call to exit() will * automatically be made. * * Note that four (and only four) arguments must be passed for the spawned * functions. * * Input Parameters: * name - Name of the new task * priority - Priority of the new task * stack_size - size (in bytes) of the stack needed * entry - Entry point of a new task * arg - A pointer to an array of input parameters. Up to * CONFIG_MAX_TASK_ARG parameters may be provided. If fewer * than CONFIG_MAX_TASK_ARG parameters are passed, the list * should be terminated with a NULL argv[] value. If no * parameters are required, argv may be NULL. * * Return Value: * Returns the non-zero process ID of the new task or ERROR if memory is * insufficient or the task cannot be created. The errno will be set to * indicate the nature of the error (always ENOMEM). * ****************************************************************************/ #ifndef CONFIG_BUILD_KERNEL int task_create(FAR const char *name, int priority, int stack_size, main_t entry, FAR char * const argv[]) { return thread_create(name, TCB_FLAG_TTYPE_TASK, priority, stack_size, entry, argv); } #endif /**************************************************************************** * Name: kernel_thread * * Description: * This function creates and activates a kernel thread task with kernel- * mode privileges. It is identical to task_create() except that it * configures the newly started thread to run in kernel model. * * Input Parameters: * (same as task_create()) * * Return Value: * (same as task_create()) * ****************************************************************************/ int kernel_thread(FAR const char *name, int priority, int stack_size, main_t entry, FAR char * const argv[]) { return thread_create(name, TCB_FLAG_TTYPE_KERNEL, priority, stack_size, entry, argv); }