thread_structures.h

Go to the documentation of this file.

/* -*- mode: c; c-basic-offset: 4; -*- */
/* Created by Hershal Bhave and Eric Crosson 2015-03-08 */
/* Revision history: Look in Git FGT */
#ifndef __thread_structrues__
#define __thread_structrues__

#include "libstd/defines.h"

typedef uint32_t tick_t;

#define SEMAPHORE_DEFAULT_VALUE                 0

typedef int8_t semaphore_t;

#define spinlock_until(blocker)                 \
    while (!(*blocker))

#define sem_init_(sem, initial_value)           \
    semaphore_t sem;                            \
    sem = initial_value

#define sem_guard(sem)                          \
    if(!semaphore_blocked(sem))

#define sem_take(sem)                           \
    atomic (                                    \
        --sem;                                  \
       /* TODO: wake thread */                  \
    )

/* TODO: define */
#define sem_check(sem)

#define sem_init(sem)                           \
    sem_init_(sem, SEMAPHORE_DEFAULT_VALUE)

#define sem_signal(sem)                         \
    sem_post(sem)

#define sem_post(sem)                           \
    atomic (                                    \
        ++sem;                                  \
       /* TODO: wake thread */                  \
    )

#define sem_wait(sem)                           \
    while (semaphore_blocked(sem)) {            \
        os_surrender_context();                 \
    }                                           \
    atomic (                                    \
        --sem;                                  \
    )

#define semaphore_blocked(sem)                  \
    (sem <= 0)

#define thread_blocked(tcb_t)                   \
    (tcb_t->sem != NULL)


typedef uint8_t priority_t;

typedef int32_t deadline_t;
typedef int32_t microseconds_t;         /* smallest divisible task time */

typedef enum {
    DL_HARD,
    DL_SOFT,
} DEADLINE_TYPE;

typedef struct tcb_t {

    int32_t *sp;

    struct tcb_t *next;
    struct tcb_t *prev;

    immutable int32_t id;

    priority_t priority;

    task_t entry_point;

    /* Semaphore value of this thread.
     * sem == NULL :: unblocked
     * sem contains a pointer's address :: blocked
     */
    semaphore_t* sem;

    /* int32_t sleep_timer;

    /* int8_t priority; */
} tcb_t;

typedef struct sched_task {
    task_t task;
    tcb_t* tcb;
    DEADLINE_TYPE seriousness;
    tick_t absolute_deadline;

    void* pool;

    /* For use by utlist library */
    struct sched_task *next;
    struct sched_task *prev;
    struct sched_task *pri_next;
    struct sched_task *pri_prev;
    int id;
} sched_task;

typedef struct sched_task_pool {
    frequency_t deadline;       /* Key */
    sched_task *queue;

    /* allow this structure to be hashable */
    /* UT_hash_handle hh; */
    /* Allow this structure to be linked-list-able */
    struct sched_task_pool *next, *prev;
    int id;
} sched_task_pool;

#endif

/* End Doxygen group
    * @}
     */