incubator-nuttx/include/nuttx/sched.h

349 lines
13 KiB
C

/********************************************************************************
* nuttx/sched.h
*
* Copyright (C) 2007-2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
*
********************************************************************************/
#ifndef __NUTTX_SCHED_H
#define __NUTTX_SCHED_H
/********************************************************************************
* Included Files
********************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <queue.h>
#include <signal.h>
#include <semaphore.h>
#include <pthread.h>
#include <mqueue.h>
#include <time.h>
#include <nuttx/irq.h>
#include <nuttx/net.h>
/********************************************************************************
* Pre-processor Definitions
********************************************************************************/
/* Task Management Definitins ***************************************************/
/* This is the maximum number of times that a lock can be set */
#define MAX_LOCK_COUNT 127
/* Values for the _TCB flags flag bits */
#define TCB_FLAG_TTYPE_SHIFT (0) /* Bits 0-1: thread type */
#define TCB_FLAG_TTYPE_MASK (3 << TCB_FLAG_TTYPE_SHIFT)
# define TCB_FLAG_TTYPE_TASK (0 << TCB_FLAG_TTYPE_SHIFT) /* Normal user task */
# define TCB_FLAG_TTYPE_PTHREAD (1 << TCB_FLAG_TTYPE_SHIFT) /* User pthread */
# define TCB_FLAG_TTYPE_KERNEL (2 << TCB_FLAG_TTYPE_SHIFT) /* Kernel thread */
#define TCB_FLAG_NONCANCELABLE (1 << 2) /* Bit 2: Pthread is non-cancelable */
#define TCB_FLAG_CANCEL_PENDING (1 << 3) /* Bit 3: Pthread cancel is pending */
#define TCB_FLAG_ROUND_ROBIN (1 << 4) /* Bit 4: Round robin sched enabled */
/********************************************************************************
* Global Type Definitions
********************************************************************************/
#ifndef __ASSEMBLY__
/* General Task Management Types ************************************************/
/* This is the type of the task_state field of the TCB. NOTE: the order and
* content of this enumeration is critical since there are some OS tables indexed
* by these values. The range of values is assumed to fit into a uint8_t in _TCB.
*/
enum tstate_e
{
TSTATE_TASK_INVALID = 0, /* INVALID - The TCB is uninitialized */
TSTATE_TASK_PENDING, /* READY_TO_RUN - Pending preemption unlock */
TSTATE_TASK_READYTORUN, /* READY-TO-RUN - But not running */
TSTATE_TASK_RUNNING, /* READY_TO_RUN - And running */
TSTATE_TASK_INACTIVE, /* BLOCKED - Initialized but not yet activated */
TSTATE_WAIT_SEM, /* BLOCKED - Waiting for a semaphore */
#ifndef CONFIG_DISABLE_SIGNALS
TSTATE_WAIT_SIG, /* BLOCKED - Waiting for a signal */
#endif
#ifndef CONFIG_DISABLE_MQUEUE
TSTATE_WAIT_MQNOTEMPTY, /* BLOCKED - Waiting for a MQ to become not empty. */
TSTATE_WAIT_MQNOTFULL, /* BLOCKED - Waiting for a MQ to become not full. */
#endif
#ifdef CONFIG_PAGING
TSTATE_WAIT_PAGEFILL, /* BLOCKED - Waiting for page fill */
#endif
NUM_TASK_STATES /* Must be last */
};
typedef enum tstate_e tstate_t;
/* The following definitions are determined by tstate_t */
#define FIRST_READY_TO_RUN_STATE TSTATE_TASK_READYTORUN
#define LAST_READY_TO_RUN_STATE TSTATE_TASK_RUNNING
#define FIRST_BLOCKED_STATE TSTATE_TASK_INACTIVE
#define LAST_BLOCKED_STATE (NUM_TASK_STATES-1)
/* The following is the form of a thread start-up function */
typedef void (*start_t)(void);
/* This is the entry point into the main thread of the task or into a created
* pthread within the task.
*/
union entry_u
{
pthread_startroutine_t pthread;
main_t main;
};
typedef union entry_u entry_t;
/* This is the type of the function that is executed with exit() is called
* (if registered via atexit()).
*/
#ifdef CONFIG_SCHED_ATEXIT
typedef void (*exitfunc_t)(void);
#endif
/* POSIX Message queue */
typedef struct msgq_s msgq_t;
/* The structure used to maintain environment variables */
#ifndef CONFIG_DISABLE_ENVIRON
struct environ_s
{
unsigned int ev_crefs; /* Reference count used when environment
* is shared by threads */
size_t ev_alloc; /* Number of bytes allocated in environment */
char ev_env[1]; /* Environment strings */
};
typedef struct environ_s environ_t;
# define SIZEOF_ENVIRON_T(alloc) (sizeof(environ_t) + alloc - 1)
#endif
/* This structure describes a reference counted D-Space region */
struct dspace_s
{
uint32_t crefs; /* This is the number of pthreads that shared the
* the same D-Space */
uint8_t region[1]; /* Beginning of the allocated region */
};
#define SIZEOF_DSPACE_S(n) (sizeof(struct dspace_s) - 1 + (n))
/* This is the task control block (TCB) */
struct _TCB
{
/* Fields used to support list management *************************************/
FAR struct _TCB *flink; /* link in DQ of TCBs */
FAR struct _TCB *blink;
/* Task Management Fields *****************************************************/
pid_t pid; /* This is the ID of the thread */
start_t start; /* Thread start function */
entry_t entry; /* Entry Point into the thread */
#ifdef CONFIG_SCHED_ATEXIT
exitfunc_t exitfunc; /* Called if exit is called. */
#endif
#ifdef CONFIG_SCHED_WAITPID /* Experimental */
sem_t exitsem; /* Support for waitpid */
int *stat_loc; /* Location to return exit status */
#endif
uint8_t sched_priority; /* Current priority of the thread */
#ifdef CONFIG_PRIORITY_INHERITANCE
# if CONFIG_SEM_NNESTPRIO > 0
uint8_t npend_reprio; /* Number of nested reprioritizations */
uint8_t pend_reprios[CONFIG_SEM_NNESTPRIO];
# endif
uint8_t base_priority; /* "Normal" priority of the thread */
#endif
uint8_t task_state; /* Current state of the thread */
uint16_t flags; /* Misc. general status flags */
int16_t lockcount; /* 0=preemptable (not-locked) */
#ifndef CONFIG_DISABLE_PTHREAD
FAR void *joininfo; /* Detach-able info to support join */
#endif
#if CONFIG_RR_INTERVAL > 0
int timeslice; /* RR timeslice interval remaining */
#endif
/* Values needed to restart a task ********************************************/
uint8_t init_priority; /* Initial priority of the task */
char *argv[CONFIG_MAX_TASK_ARGS+1]; /* Name+start-up parameters */
#ifndef CONFIG_DISABLE_ENVIRON
FAR environ_t *envp; /* Environment variables */
#endif
/* Stack-Related Fields *******************************************************/
#ifndef CONFIG_CUSTOM_STACK
size_t adj_stack_size; /* Stack size after adjustment */
/* for hardware, processor, etc. */
/* (for debug purposes only) */
FAR void *stack_alloc_ptr; /* Pointer to allocated stack */
/* Need to deallocate stack */
FAR void *adj_stack_ptr; /* Adjusted stack_alloc_ptr for HW */
/* The initial stack pointer value */
#endif
/* External Module Support ****************************************************/
#ifdef CONFIG_PIC
FAR struct dspace_s *dspace; /* Allocated area for .bss and .data */
#endif
/* POSIX Thread Specific Data *************************************************/
#if !defined(CONFIG_DISABLE_PTHREAD) && CONFIG_NPTHREAD_KEYS > 0
FAR void *pthread_data[CONFIG_NPTHREAD_KEYS];
#endif
/* POSIX Semaphore Control Fields *********************************************/
sem_t *waitsem; /* Semaphore ID waiting on */
/* POSIX Signal Control Fields ************************************************/
#ifndef CONFIG_DISABLE_SIGNALS
sigset_t sigprocmask; /* Signals that are blocked */
sigset_t sigwaitmask; /* Waiting for pending signals */
sq_queue_t sigactionq; /* List of actions for signals */
sq_queue_t sigpendingq; /* List of Pending Signals */
sq_queue_t sigpendactionq; /* List of pending signal actions */
sq_queue_t sigpostedq; /* List of posted signals */
siginfo_t sigunbinfo; /* Signal info when task unblocked */
#endif
/* POSIX Named Message Queue Fields *******************************************/
#ifndef CONFIG_DISABLE_MQUEUE
sq_queue_t msgdesq; /* List of opened message queues */
FAR msgq_t *msgwaitq; /* Waiting for this message queue */
#endif
/* Library related fields *****************************************************/
int pterrno; /* Current per-thread errno */
/* File system support ********************************************************/
#if CONFIG_NFILE_DESCRIPTORS > 0
FAR struct filelist *filelist; /* Maps file descriptor to file */
#endif
#if CONFIG_NFILE_STREAMS > 0
FAR struct streamlist *streams; /* Holds C buffered I/O info */
#endif
/* Network socket *************************************************************/
#if CONFIG_NSOCKET_DESCRIPTORS > 0
FAR struct socketlist *sockets; /* Maps file descriptor to file */
#endif
/* State save areas ***********************************************************/
/* The form and content of these fields are processor-specific. */
struct xcptcontext xcp; /* Interrupt register save area */
#if CONFIG_TASK_NAME_SIZE > 0
char name[CONFIG_TASK_NAME_SIZE]; /* Task name */
#endif
};
typedef struct _TCB _TCB;
/* This is the callback type used by sched_foreach() */
typedef void (*sched_foreach_t)(FAR _TCB *tcb, FAR void *arg);
#endif /* __ASSEMBLY__ */
/********************************************************************************
* Global Function Prototypes
********************************************************************************/
#ifndef __ASSEMBLY__
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif
/* TCB helpers */
EXTERN FAR _TCB *sched_self(void);
/* File system helpers */
#if CONFIG_NFILE_DESCRIPTORS > 0
EXTERN FAR struct filelist *sched_getfiles(void);
#if CONFIG_NFILE_STREAMS > 0
EXTERN FAR struct streamlist *sched_getstreams(void);
#endif /* CONFIG_NFILE_STREAMS */
#endif /* CONFIG_NFILE_DESCRIPTORS */
#if CONFIG_NSOCKET_DESCRIPTORS > 0
EXTERN FAR struct socketlist *sched_getsockets(void);
#endif /* CONFIG_NSOCKET_DESCRIPTORS */
/* sched_foreach will enumerate over each task and provide the
* TCB of each task to a user callback functions. Interrupts
* will be disabled throughout this enumeration!
*/
EXTERN void sched_foreach(sched_foreach_t handler, FAR void *arg);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* __NUTTX_SCHED_H */