C++ (Cpp) number_of_lowest_bit Examples

Example #1

File: sched.c Project: benpicco/RIOT-old

void sched_run() {
    sched_context_switch_request = 0;

    tcb_t *my_active_thread = (tcb_t*)active_thread;

    if (my_active_thread) {
        if( my_active_thread->status ==  STATUS_RUNNING) {
            my_active_thread->status =  STATUS_PENDING;
        }

#ifdef SCHED_TEST_STACK
        if (*((unsigned int*)my_active_thread->stack_start) != (unsigned int) my_active_thread->stack_start) {
            printf("scheduler(): stack overflow detected, task=%s pid=%u\n", my_active_thread->name, my_active_thread->pid);
        }
#endif

    }

#if SCHEDSTATISTICS
    extern unsigned long hwtimer_now(void);
    unsigned int time = hwtimer_now();
    if (my_active_thread && (pidlist[my_active_thread->pid].laststart)) {
        pidlist[my_active_thread->pid].runtime += time - pidlist[my_active_thread->pid].laststart;
    }
#endif

    DEBUG("\nscheduler: previous task: %s\n", ( my_active_thread == NULL) ? "none" : my_active_thread->name );

    if (num_tasks == 0) {
        DEBUG("scheduler: no tasks left.\n");
        while(! num_tasks);
        DEBUG("scheduler: new task created.\n");
    }

    my_active_thread = NULL;
    while(! my_active_thread) {

        //        for (int i = 0; i < SCHED_PRIO_LEVELS; i++) { /* TODO: introduce bitfield cache */
        //            if (runqueues[i]) {
        int nextrq = number_of_lowest_bit(runqueue_bitcache);
        clist_node_t next = *(runqueues[nextrq]);
        DEBUG("scheduler: first in queue: %s\n", ((tcb_t*)next.data)->name);
        clist_advance(&(runqueues[nextrq]));
        my_active_thread = (tcb_t*)next.data;
        thread_pid = (volatile int) my_active_thread->pid;
#if SCHEDSTATISTICS
        pidlist[my_active_thread->pid].laststart = time;
        pidlist[my_active_thread->pid].schedules ++;
#endif
        //                break;
        //            }
        //        }
        if (active_thread->pid != last_pid) {
            last_pid = active_thread->pid;
        }
    }

    DEBUG("scheduler: next task: %s\n", my_active_thread->name);

    if (my_active_thread != active_thread) {
        if (active_thread != NULL) { //TODO: necessary?
            if (active_thread->status ==  STATUS_RUNNING) {
                active_thread->status =  STATUS_PENDING ;
            }
        }
        sched_set_status((tcb_t*)my_active_thread,  STATUS_RUNNING);
    }

    active_thread = (volatile tcb_t*) my_active_thread;

    DEBUG("scheduler: done.\n");
}

Example #2

File: sched.c Project: JarvisW/ez430_RIOT

void sched_run()
{
    sched_context_switch_request = 0;

    tcb_t *my_active_thread = (tcb_t *)active_thread;

    if (my_active_thread) {
        if (my_active_thread->status == STATUS_RUNNING) {
            my_active_thread->status = STATUS_PENDING;
        }

#ifdef SCHED_TEST_STACK

        if (*((unsigned int *)my_active_thread->stack_start) != (unsigned int) my_active_thread->stack_start) {
            printf("scheduler(): stack overflow detected, task=%s pid=%u\n", my_active_thread->name, my_active_thread->pid);
        }

#endif

    }

#ifdef SCHEDSTATISTICS
    unsigned long time = hwtimer_now();

    if (my_active_thread && (pidlist[my_active_thread->pid].laststart)) {
        pidlist[my_active_thread->pid].runtime_ticks += time - pidlist[my_active_thread->pid].laststart;
    }

#endif

    DEBUG("\nscheduler: previous task: %s\n", (my_active_thread == NULL) ? "none" : my_active_thread->name);

    if (num_tasks == 0) {
        DEBUG("scheduler: no tasks left.\n");

        while (!num_tasks) {
            /* loop until a new task arrives */
            ;
        }

        DEBUG("scheduler: new task created.\n");
    }

    my_active_thread = NULL;

    while (!my_active_thread) {
        int nextrq = number_of_lowest_bit(runqueue_bitcache);
        clist_node_t next = *(runqueues[nextrq]);
        DEBUG("scheduler: first in queue: %s\n", ((tcb_t *)next.data)->name);
        clist_advance(&(runqueues[nextrq]));
        my_active_thread = (tcb_t *)next.data;
        thread_pid = (volatile int) my_active_thread->pid;
#if SCHEDSTATISTICS
        pidlist[my_active_thread->pid].laststart = time;
        pidlist[my_active_thread->pid].schedules++;
        if ((sched_cb) && (my_active_thread->pid != last_pid)) {
            sched_cb(hwtimer_now(), my_active_thread->pid);
            last_pid = my_active_thread->pid;
        }
#endif
#ifdef MODULE_NSS

        if (active_thread && active_thread->pid != last_pid) {
            last_pid = active_thread->pid;
        }

#endif
    }

    DEBUG("scheduler: next task: %s\n", my_active_thread->name);

    if (my_active_thread != active_thread) {
        if (active_thread != NULL) {  /* TODO: necessary? */
            if (active_thread->status ==  STATUS_RUNNING) {
                active_thread->status =  STATUS_PENDING ;
            }
        }

        sched_set_status((tcb_t *)my_active_thread,  STATUS_RUNNING);
    }

    active_thread = (volatile tcb_t *) my_active_thread;

    DEBUG("scheduler: done.\n");
}