void up_unblock_task(FAR _TCB *tcb) { /* Verify that the context switch can be performed */ if ((tcb->task_state < FIRST_BLOCKED_STATE) || (tcb->task_state > LAST_BLOCKED_STATE)) { PANIC(OSERR_BADUNBLOCKSTATE); } else { FAR _TCB *rtcb = (FAR _TCB*)g_readytorun.head; dbg("Unblocking TCB=%p\n", tcb); /* Remove the task from the blocked task list */ sched_removeblocked(tcb); /* Reset its timeslice. This is only meaningful for round * robin tasks but it doesn't here to do it for everything */ #if CONFIG_RR_INTERVAL > 0 tcb->timeslice = CONFIG_RR_INTERVAL / MSEC_PER_TICK; #endif /* Add the task in the correct location in the prioritized * g_readytorun task list */ if (sched_addreadytorun(tcb)) { /* The currently active task has changed! We need to do * a context switch to the new task. * * Are we in an interrupt handler? */ if (g_irqtos) { /* Yes, then we have to do things differently. * Just copy the current stack into the OLD rtcb. */ up_saveirqcontext(&rtcb->xcp); /* Restore the exception context of the rtcb at the (new) head * of the g_readytorun task list. */ rtcb = (FAR _TCB*)g_readytorun.head; dbg("New Active Task TCB=%p\n", rtcb); /* Then setup so that the context will be performed on exit * from the interrupt. */ g_irqcontext = &rtcb->xcp; } /* We are not in an interrupt andler. Copy the user C context * into the TCB of the task that was previously active. if * up_savecontext returns a non-zero value, then this is really the * previously running task restarting! */ else if (!up_savecontext(&rtcb->xcp)) { /* Restore the exception context of the new task that is ready to * run (probably tcb). This is the new rtcb at the head of the * g_readytorun task list. */ rtcb = (FAR _TCB*)g_readytorun.head; dbg("New Active Task TCB=%p\n", rtcb); /* Then switch contexts */ up_restorecontext(&rtcb->xcp); } } } }
void up_block_task(FAR struct tcb_s *tcb, tstate_t task_state) { FAR struct tcb_s *rtcb = (FAR struct tcb_s*)g_readytorun.head; bool switch_needed; /* Verify that the context switch can be performed */ ASSERT((tcb->task_state >= FIRST_READY_TO_RUN_STATE) && (tcb->task_state <= LAST_READY_TO_RUN_STATE)); dbg("Blocking TCB=%p\n", tcb); /* Remove the tcb task from the ready-to-run list. If we * are blocking the task at the head of the task list (the * most likely case), then a context switch to the next * ready-to-run task is needed. In this case, it should * also be true that rtcb == tcb. */ switch_needed = sched_removereadytorun(tcb); /* Add the task to the specified blocked task list */ sched_addblocked(tcb, (tstate_t)task_state); /* If there are any pending tasks, then add them to the g_readytorun * task list now */ if (g_pendingtasks.head) { switch_needed |= sched_mergepending(); } /* Now, perform the context switch if one is needed */ if (switch_needed) { /* Are we in an interrupt handler? */ if (g_irqtos) { /* Yes, then we have to do things differently. * Just copy the current registers into the OLD rtcb. */ up_saveirqcontext(&tcb->xcp); /* Restore the exception context of the rtcb at the (new) head * of the g_readytorun task list. */ rtcb = (FAR struct tcb_s*)g_readytorun.head; dbg("New Active Task TCB=%p\n", rtcb); /* Then setup so that the context will be performed on exit * from the interrupt. */ g_irqcontext = &rtcb->xcp; } /* Copy the user C context into the TCB at the (old) head of the * g_readytorun Task list. if up_savecontext returns a non-zero * value, then this is really the previously running task restarting! */ else if (!up_savecontext(&rtcb->xcp)) { /* Restore the exception context of the rtcb at the (new) head * of the g_readytorun task list. */ rtcb = (FAR struct tcb_s*)g_readytorun.head; dbg("New Active Task TCB=%p\n", rtcb); /* Then switch contexts */ up_restorecontext(&rtcb->xcp); } } }