void up_release_pending(void)
{
_TCB *rtcb = (_TCB*)g_readytorun.head;
slldbg("From TCB=%p\n", rtcb);
/* Merge the g_pendingtasks list into the g_readytorun task list */
/* sched_lock(); */
if (sched_mergepending())
{
/* The currently active task has changed! We will need to
* switch contexts. First check if we are operating in
* interrupt context:
*/
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* Copy the exception context into the TCB of the task that
* was currently active. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task
* restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
void up_release_pending(void)
{
_TCB *rtcb = (_TCB*)g_readytorun.head;
slldbg("From TCB=%p\n", rtcb);
/* Merge the g_pendingtasks list into the g_readytorun task list */
/* sched_lock(); */
if (sched_mergepending())
{
/* The currently active task has changed! We will need to
* switch contexts. First check if we are operating in
* interrupt context:
*/
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
_TCB *nexttcb = (_TCB*)g_readytorun.head;
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
void up_unblock_task(_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
{
_TCB *rtcb = (_TCB*)g_readytorun.head;
/* 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 (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* We are not in an interrupt handler. Copy the user C context
* into the TCB of the task that was previously active. if
* up_saveusercontext returns a non-zero value, then this is really the
* previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* 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 = (_TCB*)g_readytorun.head;
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
}
void up_block_task(struct tcb_s *tcb, tstate_t task_state)
{
struct tcb_s *rtcb = this_task();
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));
/* 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 ready-to-run
* task list now
*/
if (g_pendingtasks.head)
{
switch_needed |= sched_mergepending();
}
/* Now, perform the context switch if one is needed */
if (switch_needed)
{
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we in an interrupt handler? */
if (CURRENT_REGS)
{
/* Yes, then we have to do things differently.
* Just copy the CURRENT_REGS into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Reset scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* Copy the user C context into the TCB at the (old) head of the
* ready-to-run Task list. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(rtcb);
#endif
/* Reset scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
void up_release_pending(void)
{
struct tcb_s *rtcb = this_task();
sinfo("From TCB=%p\n", rtcb);
/* Merge the g_pendingtasks list into the ready-to-run task list */
/* sched_lock(); */
if (sched_mergepending())
{
/* The currently active task has changed! We will need to switch
* contexts.
*/
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we operating in interrupt context? */
if (CURRENT_REGS)
{
/* Yes, then we have to do things differently. Just copy the
* CURRENT_REGS into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
struct tcb_s *nexttcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(nexttcb);
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
/* Refuse to handle nested signal actions */
sdbg("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
if (!tcb->xcp.sigdeliver)
{
irqstate_t flags;
/* Make sure that interrupts are disabled */
flags = irqsave();
/* First, handle some special cases when the signal is
* being delivered to the currently executing task.
*/
sdbg("rtcb=0x%p current_regs=0x%p\n", g_readytorun.head, current_regs);
if (tcb == (struct tcb_s*)g_readytorun.head)
{
/* CASE 1: We are not in an interrupt handler and
* a task is signalling itself for some reason.
*/
if (!current_regs)
{
/* In this case just deliver the signal now. */
sigdeliver(tcb);
}
/* CASE 2: We are in an interrupt handler AND the
* interrupted task is the same as the one that
* must receive the signal, then we will have to modify
* the return state as well as the state in the TCB.
*
* Hmmm... there looks like a latent bug here: The following
* logic would fail in the strange case where we are in an
* interrupt handler, the thread is signalling itself, but
* a context switch to another task has occurred so that
* current_regs does not refer to the thread at g_readytorun.head!
*/
else
{
/* Save the return lr and cpsr and one scratch register
* These will be restored by the signal trampoline after
* the signals have been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_pc = current_regs[REG_PC];
tcb->xcp.saved_basepri = current_regs[REG_BASEPRI];
tcb->xcp.saved_xpsr = current_regs[REG_XPSR];
/* Then set up to vector to the trampoline with interrupts
* disabled. The kernel-space trampoline must run in
* privileged thread mode.
*/
current_regs[REG_PC] = (uint32_t)up_sigdeliver;
current_regs[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
current_regs[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_NUTTX_KERNEL
current_regs[REG_XPSR] = EXC_RETURN_PRIVTHR;
#endif
/* And make sure that the saved context in the TCB
* is the same as the interrupt return context.
*/
up_savestate(tcb->xcp.regs);
}
}
/* Otherwise, we are (1) signaling a task is not running
* from an interrupt handler or (2) we are not in an
* interrupt handler and the running task is signalling
* some non-running task.
*/
else
{
/* Save the return lr and cpsr and one scratch register
* These will be restored by the signal trampoline after
* the signals have been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
tcb->xcp.saved_basepri = tcb->xcp.regs[REG_BASEPRI];
tcb->xcp.saved_xpsr = tcb->xcp.regs[REG_XPSR];
/* Then set up to vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode
* to be here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
tcb->xcp.regs[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
tcb->xcp.regs[REG_XPSR] = ARMV6M_XPSR_T;
}
irqrestore(flags);
}
}
void up_reprioritize_rtr(struct tcb_s *tcb, uint8_t priority)
{
/* Verify that the caller is sane */
if (tcb->task_state < FIRST_READY_TO_RUN_STATE ||
tcb->task_state > LAST_READY_TO_RUN_STATE
#if SCHED_PRIORITY_MIN > 0
|| priority < SCHED_PRIORITY_MIN
#endif
#if SCHED_PRIORITY_MAX < UINT8_MAX
|| priority > SCHED_PRIORITY_MAX
#endif
)
{
PANIC();
}
else
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
bool switch_needed;
slldbg("TCB=%p PRI=%d\n", tcb, priority);
/* Remove the tcb task from the ready-to-run list.
* sched_removereadytorun will return true if we just removed the head
* of the ready to run list.
*/
switch_needed = sched_removereadytorun(tcb);
/* Setup up the new task priority */
tcb->sched_priority = (uint8_t)priority;
/* Return the task to the ready-to-run task list. sched_addreadytorun
* will return true if the task was added to the head of ready-to-run
* list. We will need to perform a context switch only if the
* EXCLUSIVE or of the two calls is non-zero (i.e., one and only one
* the calls changes the head of the ready-to-run list).
*/
switch_needed ^= sched_addreadytorun(tcb);
/* Now, perform the context switch if one is needed (i.e. if the head
* of the ready-to-run list is no longer the same).
*/
if (switch_needed)
{
/* If we are going to do a context switch, then now is the right
* time to add any pending tasks back into the ready-to-run list.
* task list now
*/
if (g_pendingtasks.head)
{
sched_mergepending();
}
/* Are we in an interrupt handler? */
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
struct tcb_s *nexttcb = (struct tcb_s*)g_readytorun.head;
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
}
void up_reprioritize_rtr(struct tcb_s *tcb, uint8_t priority)
{
/* Verify that the caller is sane */
if (tcb->task_state < FIRST_READY_TO_RUN_STATE ||
tcb->task_state > LAST_READY_TO_RUN_STATE
#if SCHED_PRIORITY_MIN > 0
|| priority < SCHED_PRIORITY_MIN
#endif
#if SCHED_PRIORITY_MAX < UINT8_MAX
|| priority > SCHED_PRIORITY_MAX
#endif
)
{
PANIC();
}
else
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
bool switch_needed;
slldbg("TCB=%p PRI=%d\n", tcb, priority);
/* Remove the tcb task from the ready-to-run list.
* sched_removereadytorun will return true if we just
* remove the head of the ready to run list.
*/
switch_needed = sched_removereadytorun(tcb);
/* Setup up the new task priority */
tcb->sched_priority = (uint8_t)priority;
/* Return the task to the specified blocked task list.
* sched_addreadytorun will return true if the task was
* added to the new list. We will need to perform a context
* switch only if the EXCLUSIVE or of the two calls is non-zero
* (i.e., one and only one the calls changes the head of the
* ready-to-run list).
*/
switch_needed ^= sched_addreadytorun(tcb);
/* Now, perform the context switch if one is needed */
if (switch_needed)
{
/* If we are going to do a context switch, then now is the right
* time to add any pending tasks back into the ready-to-run list.
* task list now
*/
if (g_pendingtasks.head)
{
sched_mergepending();
}
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we in an interrupt handler? */
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* Copy the exception context into the TCB at the (old) head of the
* g_readytorun Task list. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(rtcb);
#endif
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
}
void up_unblock_task(struct tcb_s *tcb)
{
struct tcb_s *rtcb = this_task();
/* Verify that the context switch can be performed */
DEBUGASSERT((tcb->task_state >= FIRST_BLOCKED_STATE) &&
(tcb->task_state <= LAST_BLOCKED_STATE));
/* Remove the task from the blocked task list */
sched_removeblocked(tcb);
/* Add the task in the correct location in the prioritized
* ready-to-run task list
*/
if (sched_addreadytorun(tcb))
{
/* The currently active task has changed! We need to do
* a context switch to the new task.
*/
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we in an interrupt handler? */
if (g_current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the g_current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* We are not in an interrupt handler. Copy the user C context
* into the TCB of the task that was previously active. if
* up_saveusercontext returns a non-zero value, then this is really the
* previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* 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
* ready-to-run task list.
*/
rtcb = this_task();
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(rtcb);
#endif
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
irqstate_t flags;
sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
DEBUGASSERT(tcb != NULL && sigdeliver != NULL);
/* Make sure that interrupts are disabled */
flags = enter_critical_section();
/* Refuse to handle nested signal actions */
if (tcb->xcp.sigdeliver == NULL)
{
/* First, handle some special cases when the signal is being delivered
* to the currently executing task.
*/
sinfo("rtcb=0x%p CURRENT_REGS=0x%p\n", this_task(), CURRENT_REGS);
if (tcb == this_task())
{
/* CASE 1: We are not in an interrupt handler and a task is
* signaling itself for some reason.
*/
if (!CURRENT_REGS)
{
/* In this case just deliver the signal now.
* REVISIT: Signal handle will run in a critical section!
*/
sigdeliver(tcb);
}
/* CASE 2: We are in an interrupt handler AND the interrupted
* task is the same as the one that must receive the signal, then
* we will have to modify the return state as well as the state in
* the TCB.
*/
else
{
/* Save the return PC, CPSR and either the BASEPRI or PRIMASK
* registers (and perhaps also the LR). These will be
* restored by the signal trampoline after the signal has been
* delivered.
*/
tcb->xcp.sigdeliver = (FAR void *)sigdeliver;
tcb->xcp.saved_pc = CURRENT_REGS[REG_PC];
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.saved_basepri = CURRENT_REGS[REG_BASEPRI];
#else
tcb->xcp.saved_primask = CURRENT_REGS[REG_PRIMASK];
#endif
tcb->xcp.saved_xpsr = CURRENT_REGS[REG_XPSR];
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.saved_lr = CURRENT_REGS[REG_LR];
#endif
/* Then set up to vector to the trampoline with interrupts
* disabled. The kernel-space trampoline must run in
* privileged thread mode.
*/
CURRENT_REGS[REG_PC] = (uint32_t)up_sigdeliver;
#ifdef CONFIG_ARMV7M_USEBASEPRI
CURRENT_REGS[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
#else
CURRENT_REGS[REG_PRIMASK] = 1;
#endif
CURRENT_REGS[REG_XPSR] = ARMV7M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
CURRENT_REGS[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
/* And make sure that the saved context in the TCB is the same
* as the interrupt return context.
*/
up_savestate(tcb->xcp.regs);
}
}
/* Otherwise, we are (1) signaling a task is not running from an
* interrupt handler or (2) we are not in an interrupt handler and the
* running task is signaling* some non-running task.
*/
else
{
/* Save the return PC, CPSR and either the BASEPRI or PRIMASK
* registers (and perhaps also the LR). These will be restored
* by the signal trampoline after the signal has been delivered.
*/
tcb->xcp.sigdeliver = (FAR void *)sigdeliver;
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.saved_basepri = tcb->xcp.regs[REG_BASEPRI];
#else
tcb->xcp.saved_primask = tcb->xcp.regs[REG_PRIMASK];
#endif
tcb->xcp.saved_xpsr = tcb->xcp.regs[REG_XPSR];
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.saved_lr = tcb->xcp.regs[REG_LR];
#endif
/* Then set up to vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode to be
* here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.regs[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
#else
tcb->xcp.regs[REG_PRIMASK] = 1;
#endif
tcb->xcp.regs[REG_XPSR] = ARMV7M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
}
leave_critical_section(flags);
}
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
irqstate_t flags;
int cpu;
int me;
sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
/* Make sure that interrupts are disabled */
flags = enter_critical_section();
/* Refuse to handle nested signal actions */
if (!tcb->xcp.sigdeliver)
{
/* First, handle some special cases when the signal is being delivered
* to task that is currently executing on any CPU.
*/
sinfo("rtcb=0x%p CURRENT_REGS=0x%p\n", this_task(), CURRENT_REGS);
if (tcb->task_state == TSTATE_TASK_RUNNING)
{
me = this_cpu();
cpu = tcb->cpu;
/* CASE 1: We are not in an interrupt handler and a task is
* signaling itself for some reason.
*/
if (cpu == me && !CURRENT_REGS)
{
/* In this case just deliver the signal now.
* REVISIT: Signal handler will run in a critical section!
*/
sigdeliver(tcb);
}
/* CASE 2: The task that needs to receive the signal is running.
* This could happen if the task is running on another CPU OR if
* we are in an interrupt handler and the task is running on this
* CPU. In the former case, we will have to PAUSE the other CPU
* first. But in either case, we will have to modify the return
* state as well as the state in the TCB.
*/
else
{
/* If we signaling a task running on the other CPU, we have
* to PAUSE the other CPU.
*/
if (cpu != me)
{
/* Pause the CPU */
up_cpu_pause(cpu);
/* Wait while the pause request is pending */
while (up_cpu_pausereq(cpu))
{
}
/* Now tcb on the other CPU can be accessed safely */
/* Copy tcb->xcp.regs to tcp.xcp.saved. These will be restored
* by the signal trampoline after the signal has been delivered.
*/
tcb->xcp.sigdeliver = (FAR void *)sigdeliver;
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.saved_basepri = tcb->xcp.regs[REG_BASEPRI];
#else
tcb->xcp.saved_primask = tcb->xcp.regs[REG_PRIMASK];
#endif
tcb->xcp.saved_xpsr = tcb->xcp.regs[REG_XPSR];
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.saved_lr = tcb->xcp.regs[REG_LR];
#endif
/* Then set up vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode
* to be here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.regs[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
#else
tcb->xcp.regs[REG_PRIMASK] = 1;
#endif
tcb->xcp.regs[REG_XPSR] = ARMV7M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
else
{
/* tcb is running on the same CPU */
/* Save the return PC, CPSR and either the BASEPRI or PRIMASK
* registers (and perhaps also the LR). These will be
* restored by the signal trampoline after the signal has been
* delivered.
*/
tcb->xcp.sigdeliver = (FAR void *)sigdeliver;
tcb->xcp.saved_pc = CURRENT_REGS[REG_PC];
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.saved_basepri = CURRENT_REGS[REG_BASEPRI];
#else
tcb->xcp.saved_primask = CURRENT_REGS[REG_PRIMASK];
#endif
tcb->xcp.saved_xpsr = CURRENT_REGS[REG_XPSR];
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.saved_lr = CURRENT_REGS[REG_LR];
#endif
/* Then set up vector to the trampoline with interrupts
* disabled. The kernel-space trampoline must run in
* privileged thread mode.
*/
CURRENT_REGS[REG_PC] = (uint32_t)up_sigdeliver;
#ifdef CONFIG_ARMV7M_USEBASEPRI
CURRENT_REGS[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
#else
CURRENT_REGS[REG_PRIMASK] = 1;
#endif
CURRENT_REGS[REG_XPSR] = ARMV7M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
CURRENT_REGS[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
/* And make sure that the saved context in the TCB is the same
* as the interrupt return context.
*/
up_savestate(tcb->xcp.regs);
}
/* Increment the IRQ lock count so that when the task is restarted,
* it will hold the IRQ spinlock.
*/
DEBUGASSERT(tcb->irqcount < INT16_MAX);
tcb->irqcount++;
/* In an SMP configuration, the interrupt disable logic also
* involves spinlocks that are configured per the TCB irqcount
* field. This is logically equivalent to enter_critical_section().
* The matching call to leave_critical_section() will be
* performed in up_sigdeliver().
*/
spin_setbit(&g_cpu_irqset, cpu, &g_cpu_irqsetlock,
&g_cpu_irqlock);
/* RESUME the other CPU if it was PAUSED */
if (cpu != me)
{
up_cpu_resume(cpu);
}
}
}
/* Otherwise, we are (1) signaling a task is not running from an
* interrupt handler or (2) we are not in an interrupt handler and the
* running task is signaling some other non-running task.
*/
else
{
/* Save the return PC, CPSR and either the BASEPRI or PRIMASK
* registers (and perhaps also the LR). These will be restored
* by the signal trampoline after the signal has been delivered.
*/
tcb->xcp.sigdeliver = (FAR void *)sigdeliver;
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.saved_basepri = tcb->xcp.regs[REG_BASEPRI];
#else
tcb->xcp.saved_primask = tcb->xcp.regs[REG_PRIMASK];
#endif
tcb->xcp.saved_xpsr = tcb->xcp.regs[REG_XPSR];
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.saved_lr = tcb->xcp.regs[REG_LR];
#endif
/* Increment the IRQ lock count so that when the task is restarted,
* it will hold the IRQ spinlock.
*/
DEBUGASSERT(tcb->irqcount < INT16_MAX);
tcb->irqcount++;
/* Then set up to vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode to be
* here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
#ifdef CONFIG_ARMV7M_USEBASEPRI
tcb->xcp.regs[REG_BASEPRI] = NVIC_SYSH_DISABLE_PRIORITY;
#else
tcb->xcp.regs[REG_PRIMASK] = 1;
#endif
tcb->xcp.regs[REG_XPSR] = ARMV7M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
}
leave_critical_section(flags);
}
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
irqstate_t flags;
uint32_t int_ctx;
sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
/* Make sure that interrupts are disabled */
flags = enter_critical_section();
/* Refuse to handle nested signal actions */
if (!tcb->xcp.sigdeliver)
{
/* First, handle some special cases when the signal is
* being delivered to the currently executing task.
*/
sinfo("rtcb=0x%p g_current_regs=0x%p\n",
this_task(), g_current_regs);
if (tcb == this_task())
{
/* CASE 1: We are not in an interrupt handler and
* a task is signalling itself for some reason.
*/
if (!g_current_regs)
{
/* In this case just deliver the signal now. */
sigdeliver(tcb);
}
/* CASE 2: We are in an interrupt handler AND the
* interrupted task is the same as the one that
* must receive the signal, then we will have to modify
* the return state as well as the state in the TCB.
*
* Hmmm... there looks like a latent bug here: The following
* logic would fail in the strange case where we are in an
* interrupt handler, the thread is signalling itself, but
* a context switch to another task has occurred so that
* g_current_regs does not refer to the thread of this_task()!
*/
else
{
/* Save the return EPC and STATUS registers. These will be
* restored by the signal trampoline after the signals have
* been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_epc = g_current_regs[REG_EPC];
/* Then set up to vector to the trampoline with interrupts
* disabled
*/
g_current_regs[REG_EPC] = (uint32_t)up_sigdeliver;
int_ctx = g_current_regs[REG_INT_CTX];
int_ctx &= ~EPIC_STATUS_INT_PRI_MASK;
int_ctx |= EPIC_STATUS_INT_PRI1;
g_current_regs[REG_INT_CTX] = int_ctx;
/* And make sure that the saved context in the TCB
* is the same as the interrupt return context.
*/
up_savestate(tcb->xcp.regs);
sinfo("PC/STATUS Saved: %08x/%08x New: %08x/%08x\n",
tcb->xcp.saved_epc, tcb->xcp.saved_status,
g_current_regs[REG_EPC], g_current_regs[REG_STATUS]);
}
}
/* Otherwise, we are (1) signaling a task is not running
* from an interrupt handler or (2) we are not in an
* interrupt handler and the running task is signalling
* some non-running task.
*/
else
{
/* Save the return EPC and STATUS registers. These will be
* restored by the signal trampoline after the signals have
* been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_epc = tcb->xcp.regs[REG_EPC];
tcb->xcp.saved_int_ctx = tcb->xcp.regs[REG_INT_CTX];
/* Then set up to vector to the trampoline with interrupts
* disabled
*/
tcb->xcp.regs[REG_EPC] = (uint32_t)up_sigdeliver;
int_ctx = tcb->xcp.regs[REG_INT_CTX];
int_ctx &= ~EPIC_STATUS_INT_PRI_MASK;
int_ctx |= EPIC_STATUS_INT_PRI1;
tcb->xcp.regs[REG_INT_CTX] = int_ctx;
sinfo("PC/STATUS Saved: %08x/%08x New: %08x/%08x\n",
tcb->xcp.saved_epc, tcb->xcp.saved_status,
tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_STATUS]);
}
}
leave_critical_section(flags);
}
void up_release_pending(void)
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
slldbg("From TCB=%p\n", rtcb);
/* Merge the g_pendingtasks list into the g_readytorun task list */
/* sched_lock(); */
if (sched_mergepending())
{
/* The currently active task has changed! We will need to
* switch contexts. First check if we are operating in
* interrupt context:
*/
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
struct tcb_s *nexttcb = (struct tcb_s*)g_readytorun.head;
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(nexttcb);
#endif
/* Then switch contexs */
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
void up_release_pending(void)
{
struct tcb_s *rtcb = this_task();
sinfo("From TCB=%p\n", rtcb);
/* Merge the g_pendingtasks list into the ready-to-run task list */
/* sched_lock(); */
if (sched_mergepending())
{
/* The currently active task has changed! We will need to
* switch contexts.
*/
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we operating in interrupt context? */
if (CURRENT_REGS)
{
/* Yes, then we have to do things differently.
* Just copy the CURRENT_REGS into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* Copy the exception context into the TCB of the task that
* was currently active. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task
* restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
void up_block_task(_TCB *tcb, tstate_t task_state)
{
/* Verify that the context switch can be performed */
if ((tcb->task_state < FIRST_READY_TO_RUN_STATE) ||
(tcb->task_state > LAST_READY_TO_RUN_STATE))
{
PANIC(OSERR_BADBLOCKSTATE);
}
else
{
_TCB *rtcb = (_TCB*)g_readytorun.head;
bool switch_needed;
/* 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 (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
_TCB *nexttcb = (_TCB*)g_readytorun.head;
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
}
void up_block_task(struct tcb_s *tcb, tstate_t task_state)
{
struct tcb_s *rtcb = this_task();
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));
/* 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 ready-to-run
* task list now
*/
if (g_pendingtasks.head)
{
switch_needed |= sched_mergepending();
}
/* Now, perform the context switch if one is needed */
if (switch_needed)
{
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we in an interrupt handler? */
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Reset scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts. Any new address environment needed by
* the new thread will be instantiated before the return from
* interrupt.
*/
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Get the context of the task at the head of the ready to
* run list.
*/
struct tcb_s *nexttcb = this_task();
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(nexttcb);
#endif
/* Reset scheduler parameters */
sched_resume_scheduler(nexttcb);
/* Then switch contexts */
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
/* Refuse to handle nested signal actions */
sdbg("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
if (!tcb->xcp.sigdeliver)
{
irqstate_t flags;
/* Make sure that interrupts are disabled */
flags = irqsave();
/* First, handle some special cases when the signal is being delivered
* to the currently executing task.
*/
sdbg("rtcb=0x%p current_regs=0x%p\n", g_readytorun.head, current_regs);
if (tcb == (struct tcb_s*)g_readytorun.head)
{
/* CASE 1: We are not in an interrupt handler and a task is
* signalling itself for some reason.
*/
if (!current_regs)
{
/* In this case just deliver the signal now. */
sigdeliver(tcb);
}
/* CASE 2: We are in an interrupt handler AND the interrupted
* task is the same as the one that must receive the signal, then
* we will have to modify the return state as well as the state
* in the TCB.
*
* Hmmm... there looks like a latent bug here: The following logic
* would fail in the strange case where we are in an interrupt
* handler, the thread is signalling itself, but a context switch
* to another task has occurred so that current_regs does not
* refer to the thread at g_readytorun.head!
*/
else
{
/* Save the return lr and cpsr and one scratch register
* These will be restored by the signal trampoline after
* the signals have been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_pc = current_regs[REG_PC];
tcb->xcp.saved_cpsr = current_regs[REG_CPSR];
/* Then set up to vector to the trampoline with interrupts
* disabled
*/
current_regs[REG_PC] = (uint32_t)up_sigdeliver;
current_regs[REG_CPSR] = (PSR_MODE_SVC | PSR_I_BIT | PSR_F_BIT);
/* And make sure that the saved context in the TCB is the same
* as the interrupt return context.
*/
up_savestate(tcb->xcp.regs);
}
}
/* Otherwise, we are (1) signaling a task is not running from an
* interrupt handler or (2) we are not in an interrupt handler and the
* running task is signalling some non-running task.
*/
else
{
/* Save the return lr and cpsr and one scratch register. These
* will be restored by the signal trampoline after the signals
* have been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
tcb->xcp.saved_cpsr = tcb->xcp.regs[REG_CPSR];
/* Then set up to vector to the trampoline with interrupts
* disabled
*/
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
tcb->xcp.regs[REG_CPSR] = (PSR_MODE_SVC | PSR_I_BIT | PSR_F_BIT);
}
irqrestore(flags);
}
}
void up_release_pending(void)
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
slldbg("From TCB=%p\n", rtcb);
/* Merge the g_pendingtasks list into the g_readytorun task list */
/* sched_lock(); */
if (sched_mergepending())
{
/* The currently active task has changed! We will need to switch
* contexts.
*
* Update scheduler parameters.
*/
sched_suspend_scheduler(rtcb);
/* Are we operating in interrupt context? */
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* Copy the exception context into the TCB of the task that
* was currently active. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task
* restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(rtcb);
#endif
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
void up_block_task(_TCB *tcb, tstate_t task_state)
{
/* Verify that the context switch can be performed */
if ((tcb->task_state < FIRST_READY_TO_RUN_STATE) ||
(tcb->task_state > LAST_READY_TO_RUN_STATE))
{
PANIC(OSERR_BADBLOCKSTATE);
}
else
{
_TCB *rtcb = (_TCB*)g_readytorun.head;
bool switch_needed;
/* 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 (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* Copy the user C context into the TCB at the (old) head of the
* g_readytorun Task list. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (_TCB*)g_readytorun.head;
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
}
void up_reprioritize_rtr(struct tcb_s *tcb, uint8_t priority)
{
/* Verify that the caller is sane */
if (tcb->task_state < FIRST_READY_TO_RUN_STATE ||
tcb->task_state > LAST_READY_TO_RUN_STATE
#if SCHED_PRIORITY_MIN > 0
|| priority < SCHED_PRIORITY_MIN
#endif
#if SCHED_PRIORITY_MAX < UINT8_MAX
|| priority > SCHED_PRIORITY_MAX
#endif
)
{
PANIC(OSERR_BADREPRIORITIZESTATE);
}
else
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
bool switch_needed;
slldbg("TCB=%p PRI=%d\n", tcb, priority);
/* Remove the tcb task from the ready-to-run list.
* sched_removereadytorun will return true if we just
* remove the head of the ready to run list.
*/
switch_needed = sched_removereadytorun(tcb);
/* Setup up the new task priority */
tcb->sched_priority = (uint8_t)priority;
/* Return the task to the specified blocked task list.
* sched_addreadytorun will return true if the task was
* added to the new list. We will need to perform a context
* switch only if the EXCLUSIVE or of the two calls is non-zero
* (i.e., one and only one the calls changes the head of the
* ready-to-run list).
*/
switch_needed ^= sched_addreadytorun(tcb);
/* Now, perform the context switch if one is needed */
if (switch_needed)
{
/* If we are going to do a context switch, then now is the right
* time to add any pending tasks back into the ready-to-run list.
* task list now
*/
if (g_pendingtasks.head)
{
sched_mergepending();
}
/* Are we in an interrupt handler? */
if (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* Copy the exception context into the TCB at the (old) head of the
* g_readytorun Task list. if up_saveusercontext returns a non-zero
* value, then this is really the previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
slldbg("New Active Task TCB=%p\n", rtcb);
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
}
void up_unblock_task(struct tcb_s *tcb)
{
struct tcb_s *rtcb = this_task();
/* Verify that the context switch can be performed */
DEBUGASSERT((tcb->task_state >= FIRST_BLOCKED_STATE) &&
(tcb->task_state <= LAST_BLOCKED_STATE));
/* Remove the task from the blocked task list */
sched_removeblocked(tcb);
/* Add the task in the correct location in the prioritized
* ready-to-run task list
*/
if (sched_addreadytorun(tcb))
{
/* The currently active task has changed! We need to do
* a context switch to the new task.
*/
/* Update scheduler parameters */
sched_suspend_scheduler(rtcb);
/* Are we in an interrupt handler? */
if (CURRENT_REGS)
{
/* Yes, then we have to do things differently.
* Just copy the CURRENT_REGS into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the ready-to-run task list.
*/
rtcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(rtcb);
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
struct tcb_s *nexttcb = this_task();
/* Update scheduler parameters */
sched_resume_scheduler(nexttcb);
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
void up_unblock_task(struct tcb_s *tcb)
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
/* Verify that the context switch can be performed */
ASSERT((tcb->task_state >= FIRST_BLOCKED_STATE) &&
(tcb->task_state <= LAST_BLOCKED_STATE));
/* 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 = MSEC2TICK(CONFIG_RR_INTERVAL);
#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 (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(rtcb);
#endif
}
/* We are not in an interrupt handler. Copy the user C context
* into the TCB of the task that was previously active. if
* up_saveusercontext returns a non-zero value, then this is really the
* previously running task restarting!
*/
else if (!up_saveusercontext(rtcb->xcp.regs))
{
/* 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 = (struct tcb_s*)g_readytorun.head;
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(rtcb);
#endif
/* Then switch contexts */
up_fullcontextrestore(rtcb->xcp.regs);
}
}
}
void up_unblock_task(struct tcb_s *tcb)
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
/* Verify that the context switch can be performed */
ASSERT((tcb->task_state >= FIRST_BLOCKED_STATE) &&
(tcb->task_state <= LAST_BLOCKED_STATE));
/* 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 = MSEC2TICK(CONFIG_RR_INTERVAL);
#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 (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
/* Then switch contexts. Any necessary address environment
* changes will be made when the interrupt returns.
*/
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* 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.
*/
struct tcb_s *nexttcb = (struct tcb_s*)g_readytorun.head;
#ifdef CONFIG_ARCH_ADDRENV
/* Make sure that the address environment for the previously
* running task is closed down gracefully (data caches dump,
* MMU flushed) and set up the address environment for the new
* thread at the head of the ready-to-run list.
*/
(void)group_addrenv(nexttcb);
#endif
/* Then switch contexts */
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
void up_unblock_task(struct tcb_s *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
{
struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head;
/* 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 (current_regs)
{
/* Yes, then we have to do things differently.
* Just copy the current_regs into the OLD rtcb.
*/
up_savestate(rtcb->xcp.regs);
/* Restore the exception context of the rtcb at the (new) head
* of the g_readytorun task list.
*/
rtcb = (struct tcb_s*)g_readytorun.head;
/* Then switch contexts */
up_restorestate(rtcb->xcp.regs);
}
/* No, then we will need to perform the user context switch */
else
{
/* Switch context to the context of the task at the head of the
* ready to run list.
*/
struct tcb_s *nexttcb = (struct tcb_s*)g_readytorun.head;
up_switchcontext(rtcb->xcp.regs, nexttcb->xcp.regs);
/* up_switchcontext forces a context switch to the task at the
* head of the ready-to-run list. It does not 'return' in the
* normal sense. When it does return, it is because the blocked
* task is again ready to run and has execution priority.
*/
}
}
}
}
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
/* Refuse to handle nested signal actions */
sdbg("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
if (!tcb->xcp.sigdeliver)
{
irqstate_t flags;
/* Make sure that interrupts are disabled */
flags = irqsave();
/* First, handle some special cases when the signal is being delivered
* to the currently executing task.
*/
sdbg("rtcb=0x%p current_regs=0x%p\n", g_readytorun.head, current_regs);
if (tcb == (struct tcb_s*)g_readytorun.head)
{
/* CASE 1: We are not in an interrupt handler and a task is
* signalling itself for some reason.
*/
if (!current_regs)
{
/* In this case just deliver the signal now. */
sigdeliver(tcb);
}
/* CASE 2: We are in an interrupt handler AND the interrupted
* task is the same as the one that must receive the signal, then
* we will have to modify the return state as well as the state in
* the TCB.
*/
else
{
/* Save the return PC, CPSR, and PRIMASK registers (and
* perhaps the LR). These will be restored by the signal
* trampoline after the signal has been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_pc = current_regs[REG_PC];
tcb->xcp.saved_primask = current_regs[REG_PRIMASK];
tcb->xcp.saved_xpsr = current_regs[REG_XPSR];
#ifdef CONFIG_NUTTX_KERNEL
tcb->xcp.saved_lr = current_regs[REG_LR];
#endif
/* Then set up to vector to the trampoline with interrupts
* disabled. The kernel-space trampoline must run in
* privileged thread mode.
*/
current_regs[REG_PC] = (uint32_t)up_sigdeliver;
current_regs[REG_PRIMASK] = 1;
current_regs[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_NUTTX_KERNEL
current_regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
/* And make sure that the saved context in the TCB is the same
* as the interrupt return context.
*/
up_savestate(tcb->xcp.regs);
}
}
/* Otherwise, we are (1) signalling a task is not running from an
* interrupt handler or (2) we are not in an interrupt handler and the
* running task is signalling some non-running task.
*/
else
{
/* Save the return PS, CPSR and PRIMASK register (a perhaps also
* the LR). These will be restored by the signal trampoline after
* the signal has been delivered.
*/
tcb->xcp.sigdeliver = sigdeliver;
tcb->xcp.saved_pc = tcb->xcp.regs[REG_PC];
tcb->xcp.saved_primask = tcb->xcp.regs[REG_PRIMASK];
tcb->xcp.saved_xpsr = tcb->xcp.regs[REG_XPSR];
#ifdef CONFIG_NUTTX_KERNEL
tcb->xcp.saved_lr = tcb->xcp.regs[REG_LR];
#endif
/* Then set up to vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode to be
* here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)up_sigdeliver;
tcb->xcp.regs[REG_PRIMASK] = 1;
tcb->xcp.regs[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_NUTTX_KERNEL
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
irqrestore(flags);
}
}
