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Diffstat (limited to 'nuttx/sched/os_start.c')
| -rw-r--r-- | nuttx/sched/os_start.c | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/nuttx/sched/os_start.c b/nuttx/sched/os_start.c new file mode 100644 index 000000000..6cd508b8c --- /dev/null +++ b/nuttx/sched/os_start.c @@ -0,0 +1,463 @@ +/**************************************************************************** + * sched/os_start.c + * + * Copyright (C) 2007-2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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 <sys/types.h> +#include <stdbool.h> +#include <debug.h> +#include <string.h> + +#include <nuttx/arch.h> +#include <nuttx/compiler.h> +#include <nuttx/fs/fs.h> +#include <nuttx/net/net.h> +#include <nuttx/lib.h> +#include <nuttx/kmalloc.h> +#include <nuttx/init.h> + +#include "os_internal.h" +#include "sig_internal.h" +#include "wd_internal.h" +#include "sem_internal.h" +#ifndef CONFIG_DISABLE_MQUEUE +# include "mq_internal.h" +#endif +#ifndef CONFIG_DISABLE_PTHREAD +# include "pthread_internal.h" +#endif +#include "clock_internal.h" +#include "timer_internal.h" +#include "irq_internal.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Type Declarations + ****************************************************************************/ + +/**************************************************************************** + * Global Variables + ****************************************************************************/ + +/* Task Lists ***************************************************************/ +/* The state of a task is indicated both by the task_state field of the TCB + * and by a series of task lists. All of these tasks lists are declared + * below. Although it is not always necessary, most of these lists are + * prioritized so that common list handling logic can be used (only the + * g_readytorun, the g_pendingtasks, and the g_waitingforsemaphore lists need + * to be prioritized). + */ + +/* This is the list of all tasks that are ready to run. The head of this + * list is the currently active task; the tail of this list is always the + * IDLE task. + */ + +volatile dq_queue_t g_readytorun; + +/* This is the list of all tasks that are ready-to-run, but cannot be placed + * in the g_readytorun list because: (1) They are higher priority than the + * currently active task at the head of the g_readytorun list, and (2) the + * currently active task has disabled pre-emption. + */ + +volatile dq_queue_t g_pendingtasks; + +/* This is the list of all tasks that are blocked waiting for a semaphore */ + +volatile dq_queue_t g_waitingforsemaphore; + +/* This is the list of all tasks that are blocked waiting for a signal */ + +#ifndef CONFIG_DISABLE_SIGNALS +volatile dq_queue_t g_waitingforsignal; +#endif + +/* This is the list of all tasks that are blocked waiting for a message + * queue to become non-empty. + */ + +#ifndef CONFIG_DISABLE_MQUEUE +volatile dq_queue_t g_waitingformqnotempty; +#endif + +/* This is the list of all tasks that are blocked waiting for a message + * queue to become non-full. + */ + +#ifndef CONFIG_DISABLE_MQUEUE +volatile dq_queue_t g_waitingformqnotfull; +#endif + +/* This is the list of all tasks that are blocking waiting for a page fill */ + +#ifdef CONFIG_PAGING +volatile dq_queue_t g_waitingforfill; +#endif + +/* This the list of all tasks that have been initialized, but not yet + * activated. NOTE: This is the only list that is not prioritized. + */ + +volatile dq_queue_t g_inactivetasks; + +/* This is the list of dayed memory deallocations that need to be handled + * within the IDLE loop. These deallocations get queued by sched_free() + * if the OS attempts to deallocate memory while it is within an interrupt + * handler. + */ + +volatile sq_queue_t g_delayeddeallocations; + +/* This is the value of the last process ID assigned to a task */ + +volatile pid_t g_lastpid; + +/* The following hash table is used for two things: + * + * 1. This hash table greatly speeds the determination of + * a new unique process ID for a task, and + * 2. Is used to quickly map a process ID into a TCB. + * It has the side effects of using more memory and limiting + * + * the number of tasks to CONFIG_MAX_TASKS. + */ + +pidhash_t g_pidhash[CONFIG_MAX_TASKS]; + +/* This is a table of task lists. This table is indexed by + * the task state enumeration type (tstate_t) and provides + * a pointer to the associated static task list (if there + * is one) as well as a boolean indication as to if the list + * is an ordered list or not. + */ + +const tasklist_t g_tasklisttable[NUM_TASK_STATES] = +{ + { NULL, false }, /* TSTATE_TASK_INVALID */ + { &g_pendingtasks, true }, /* TSTATE_TASK_PENDING */ + { &g_readytorun, true }, /* TSTATE_TASK_READYTORUN */ + { &g_readytorun, true }, /* TSTATE_TASK_RUNNING */ + { &g_inactivetasks, false }, /* TSTATE_TASK_INACTIVE */ + { &g_waitingforsemaphore, true } /* TSTATE_WAIT_SEM */ +#ifndef CONFIG_DISABLE_SIGNALS + , + { &g_waitingforsignal, false } /* TSTATE_WAIT_SIG */ +#endif +#ifndef CONFIG_DISABLE_MQUEUE + , + { &g_waitingformqnotempty, true }, /* TSTATE_WAIT_MQNOTEMPTY */ + { &g_waitingformqnotfull, true } /* TSTATE_WAIT_MQNOTFULL */ +#endif +#ifdef CONFIG_PAGING + , + { &g_waitingforfill, true } /* TSTATE_WAIT_PAGEFILL */ +#endif +}; + +/**************************************************************************** + * Private Variables + ****************************************************************************/ +/* This is the task control block for this thread of execution. This thread + * of execution is the IDLE task. NOTE: the system boots into the IDLE + * task. The IDLE task spawns the user initialization task (user_start) and + * that user init task is responsible for bringing up the rest of the system + */ + +static FAR _TCB g_idletcb; + +/* This is the name of the idle task */ + +static FAR const char g_idlename[] = "Idle Task"; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: os_start + * + * Description: + * This function is called to initialize the operating system and to spawn + * the user initization thread of execution + * + ****************************************************************************/ + +void os_start(void) +{ + int i; + + slldbg("Entry\n"); + + /* Initialize all task lists */ + + dq_init(&g_readytorun); + dq_init(&g_pendingtasks); + dq_init(&g_waitingforsemaphore); +#ifndef CONFIG_DISABLE_SIGNALS + dq_init(&g_waitingforsignal); +#endif +#ifndef CONFIG_DISABLE_MQUEUE + dq_init(&g_waitingformqnotfull); + dq_init(&g_waitingformqnotempty); +#endif +#ifdef CONFIG_PAGING + dq_init(&g_waitingforfill); +#endif + dq_init(&g_inactivetasks); + sq_init(&g_delayeddeallocations); + + /* Initialize the logic that determine unique process IDs. */ + + g_lastpid = 0; + for (i = 0; i < CONFIG_MAX_TASKS; i++) + { + g_pidhash[i].tcb = NULL; + g_pidhash[i].pid = INVALID_PROCESS_ID; + } + + /* Assign the process ID of ZERO to the idle task */ + + g_pidhash[ PIDHASH(0)].tcb = &g_idletcb; + g_pidhash[ PIDHASH(0)].pid = 0; + + /* Initialize a TCB for this thread of execution. NOTE: The default + * value for most components of the g_idletcb are zero. The entire + * structure is set to zero. Then only the (potentially) non-zero + * elements are initialized. NOTE: The idle task is the only task in + * that has pid == 0 and sched_priority == 0. + */ + + bzero((void*)&g_idletcb, sizeof(_TCB)); + g_idletcb.task_state = TSTATE_TASK_RUNNING; + g_idletcb.entry.main = (main_t)os_start; + +#if CONFIG_TASK_NAME_SIZE > 0 + strncpy(g_idletcb.name, g_idlename, CONFIG_TASK_NAME_SIZE-1); + g_idletcb.argv[0] = g_idletcb.name; +#else + g_idletcb.argv[0] = (char*)g_idlename; +#endif /* CONFIG_TASK_NAME_SIZE */ + + /* Then add the idle task's TCB to the head of the ready to run list */ + + dq_addfirst((FAR dq_entry_t*)&g_idletcb, (FAR dq_queue_t*)&g_readytorun); + + /* Initialize the processor-specific portion of the TCB */ + + g_idletcb.flags = TCB_FLAG_TTYPE_KERNEL; + up_initial_state(&g_idletcb); + + /* Initialize the memory manager */ + +#ifndef CONFIG_HEAP_BASE + { + FAR void *heap_start; + size_t heap_size; + up_allocate_heap(&heap_start, &heap_size); + kmm_initialize(heap_start, heap_size); + } +#else + kmm_initialize((void*)CONFIG_HEAP_BASE, CONFIG_HEAP_SIZE); +#endif + + /* Initialize the interrupt handling subsystem (if included) */ + +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (irq_initialize != NULL) +#endif + { + irq_initialize(); + } + + /* Initialize the watchdog facility (if included in the link) */ + +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (wd_initialize != NULL) +#endif + { + wd_initialize(); + } + + /* Initialize the POSIX timer facility (if included in the link) */ + +#ifndef CONFIG_DISABLE_CLOCK +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (clock_initialize != NULL) +#endif + { + clock_initialize(); + } +#endif + +#ifndef CONFIG_DISABLE_POSIX_TIMERS +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (timer_initialize != NULL) +#endif + { + timer_initialize(); + } +#endif + + /* Initialize the signal facility (if in link) */ + +#ifndef CONFIG_DISABLE_SIGNALS +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (sig_initialize != NULL) +#endif + { + sig_initialize(); + } +#endif + + /* Initialize the semaphore facility. (if in link) */ + +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (sem_initialize != NULL) +#endif + { + sem_initialize(); + } + + /* Initialize the named message queue facility (if in link) */ + +#ifndef CONFIG_DISABLE_MQUEUE +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (mq_initialize != NULL) +#endif + { + mq_initialize(); + } +#endif + + /* Initialize the thread-specific data facility (if in link) */ + +#ifndef CONFIG_DISABLE_PTHREAD +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (pthread_initialize != NULL) +#endif + { + pthread_initialize(); + } +#endif + + /* Initialize the file system (needed to support device drivers) */ + +#if CONFIG_NFILE_DESCRIPTORS > 0 +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (fs_initialize != NULL) +#endif + { + fs_initialize(); + } +#endif + + /* Initialize the network system */ + +#ifdef CONFIG_NET +#if 0 + if (net_initialize != NULL) +#endif + { + net_initialize(); + } +#endif + + /* The processor specific details of running the operating system + * will be handled here. Such things as setting up interrupt + * service routines and starting the clock are some of the things + * that are different for each processor and hardware platform. + */ + + up_initialize(); + + /* Initialize the C libraries (if included in the link). This + * is done last because the libraries may depend on the above. + */ + +#ifdef CONFIG_HAVE_WEAKFUNCTIONS + if (lib_initialize != NULL) +#endif + { + lib_initialize(); + } + + /* Create stdout, stderr, stdin */ + + (void)sched_setupidlefiles(&g_idletcb); + + /* Create initial tasks and bring-up the system */ + + (void)os_bringup(); + + /* When control is return to this point, the system is idle. */ + + sdbg("Beginning Idle Loop\n"); + for (;;) + { + /* Perform garbage collection (if it is not being done by the worker + * thread). This cleans-up memory de-allocations that were queued + * because they could not be freed in that execution context (for + * example, if the memory was freed from an interrupt handler). + */ + +#ifndef CONFIG_SCHED_WORKQUEUE + /* We must have exclusive access to the memory manager to do this + * BUT the idle task cannot wait on a semaphore. So we only do + * the cleanup now if we can get the semaphore -- this should be + * possible because if the IDLE thread is running, no other task is! + */ + + if (kmm_trysemaphore() == 0) + { + sched_garbagecollection(); + kmm_givesemaphore(); + } +#endif + + /* Perform any processor-specific idle state operations */ + + up_idle(); + } +} |