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arch/: Correct critical section logic associated with the recent signal handler changes (yet again).

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This commit is contained in:
Gregory Nutt 2018-06-06 17:39:10 -06:00
parent b5c6d9c849
commit 8aa486515e
3 changed files with 115 additions and 28 deletions
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47
arch/arm/src/armv7-a/arm_sigdeliver.c
View File

@ -81,6 +81,15 @@ void up_sigdeliver(void)
int saved_errno = rtcb->pterrno;
#ifdef CONFIG_SMP
/* In the SMP case, we must terminate the critical section while the signal
* handler executes, but we also need to restore the irqcount when the
* we resume the main thread of the task.
*/
int16_t saved_irqcount;
#endif
board_autoled_on(LED_SIGNAL);
sinfo("rtcb=%p sigdeliver=%p sigpendactionq.head=%p\n",
@ -103,22 +112,27 @@ void up_sigdeliver(void)
#ifdef CONFIG_SMP
/* In the SMP case, up_schedule_sigaction(0) will have incremented
* 'irqcount' in order to force us into a critical section. At a minimum,
* we must call leave_critical_section() at least once in order to
* compensate for that.
* 'irqcount' in order to force us into a critical section. Save the
* pre-incremented irqcount.
*/
leave_critical_section(regs[REG_CPSR]);
saved_irqcount = rtcb->irqcount - 1;
DEBUGASSERT(saved_irqcount >= 0);
/* Now we need call leave_critical_section() repeatedly to get the irqcount
* to zero, freeing all global spinlocks that enforce the critical section.
*/
do
{
leave_critical_section(regs[REG_CPSR]);
}
while (rtcb->irqcount > 0);
#endif /* CONFIG_SMP */
#ifndef CONFIG_SUPPRESS_INTERRUPTS
/* Then make sure that interrupts are enabled. Signal handlers must always
* run with interrupts enabled.
*
* REVISIT: 'irqcount' could still be greater than zero in the SMP case.
* This is an issue because (1) global spinlocks are still held and (2) if
* the signal handler were to suspend the the critical section would be
* re-established when the signal handler resumes.
*/
up_irq_enable();
@ -144,8 +158,23 @@ void up_sigdeliver(void)
sinfo("Resuming\n");
(void)up_irq_save();
/* Restore the saved errno value */
rtcb->pterrno = saved_errno;
#ifdef CONFIG_SMP
/* Restore the saved 'irqcount' and recover the critical section
* spinlocks.
*/
DEBUGASSERT(rtcb->irqcount == 0);
while (rtcb->irqcount < saved_irqcount)
{
(void)enter_critical_section();
}
#endif
/* Then restore the correct state for this thread of execution. */
board_autoled_off(LED_SIGNAL);

49
arch/arm/src/armv7-m/up_sigdeliver.c
View File

@ -82,6 +82,15 @@ void up_sigdeliver(void)
int saved_errno = rtcb->pterrno;
#ifdef CONFIG_SMP
/* In the SMP case, we must terminate the critical section while the signal
* handler executes, but we also need to restore the irqcount when the
* we resume the main thread of the task.
*/
int16_t saved_irqcount;
#endif
board_autoled_on(LED_SIGNAL);
sinfo("rtcb=%p sigdeliver=%p sigpendactionq.head=%p\n",
@ -112,26 +121,31 @@ void up_sigdeliver(void)
#ifdef CONFIG_SMP
/* In the SMP case, up_schedule_sigaction(0) will have incremented
* 'irqcount' in order to force us into a critical section. At a minimum,
* we must call leave_critical_section() at least once in order to
* compensate for that.
* 'irqcount' in order to force us into a critical section. Save the
* pre-incremented irqcount.
*/
saved_irqcount = rtcb->irqcount - 1;
DEBUGASSERT(saved_irqcount >= 0);
/* Now we need call leave_critical_section() repeatedly to get the irqcount
* to zero, freeing all global spinlocks that enforce the critical section.
*/
do
{
#ifdef CONFIG_ARMV7M_USEBASEPRI
leave_critical_section((uint8_t)regs[REG_BASEPRI]);
leave_critical_section((uint8_t)regs[REG_BASEPRI]);
#else
leave_critical_section((uint16_t)regs[REG_PRIMASK]);
leave_critical_section((uint16_t)regs[REG_PRIMASK]);
#endif
}
while (rtcb->irqcount > 0);
#endif /* CONFIG_SMP */
#ifndef CONFIG_SUPPRESS_INTERRUPTS
/* Then make sure that interrupts are enabled. Signal handlers must always
* run with interrupts enabled.
*
* REVISIT: 'irqcount' could still be greater than zero in the SMP case.
* This is an issue because (1) global spinlocks are still held and (2) if
* the signal handler were to suspend the the critical section would be
* re-established when the signal handler resumes.
*/
up_irq_enable();
@ -157,8 +171,23 @@ void up_sigdeliver(void)
sinfo("Resuming\n");
(void)up_irq_save();
/* Restore the saved errno value */
rtcb->pterrno = saved_errno;
#ifdef CONFIG_SMP
/* Restore the saved 'irqcount' and recover the critical section
* spinlocks.
*/
DEBUGASSERT(rtcb->irqcount == 0);
while (rtcb->irqcount < saved_irqcount)
{
(void)enter_critical_section();
}
#endif
/* Then restore the correct state for this thread of
* execution.
*/

47
arch/xtensa/src/common/xtensa_sigdeliver.c
View File

@ -80,6 +80,15 @@ void xtensa_sig_deliver(void)
int saved_errno = rtcb->pterrno;
#ifdef CONFIG_SMP
/* In the SMP case, we must terminate the critical section while the signal
* handler executes, but we also need to restore the irqcount when the
* we resume the main thread of the task.
*/
int16_t saved_irqcount;
#endif
board_autoled_on(LED_SIGNAL);
sinfo("rtcb=%p sigdeliver=%p sigpendactionq.head=%p\n",
@ -102,22 +111,27 @@ void xtensa_sig_deliver(void)
#ifdef CONFIG_SMP
/* In the SMP case, up_schedule_sigaction(0) will have incremented
* 'irqcount' in order to force us into a critical section. At a minimum,
* we must call leave_critical_section() at least once in order to
* compensate for that.
* 'irqcount' in order to force us into a critical section. Save the
* pre-incremented irqcount.
*/
leave_critical_section((regs[REG_PS]));
saved_irqcount = rtcb->irqcount - 1;
DEBUGASSERT(saved_irqcount >= 0);
/* Now we need call leave_critical_section() repeatedly to get the irqcount
* to zero, freeing all global spinlocks that enforce the critical section.
*/
do
{
leave_critical_section((regs[REG_PS]));
}
while (rtcb->irqcount > 0);
#endif /* CONFIG_SMP */
#ifndef CONFIG_SUPPRESS_INTERRUPTS
/* Then make sure that interrupts are enabled. Signal handlers must always
* run with interrupts enabled.
*
* REVISIT: 'irqcount' could still be greater than zero in the SMP case.
* This is an issue because (1) global spinlocks are still held and (2) if
* the signal handler were to suspend the the critical section would be
* re-established when the signal handler resumes.
*/
up_irq_enable();
@ -134,8 +148,23 @@ void xtensa_sig_deliver(void)
sinfo("Resuming\n");
(void)up_irq_save();
/* Restore the saved errno value */
rtcb->pterrno = saved_errno;
#ifdef CONFIG_SMP
/* Restore the saved 'irqcount' and recover the critical section
* spinlocks.
*/
DEBUGASSERT(rtcb->irqcount == 0);
while (rtcb->irqcount < saved_irqcount)
{
(void)enter_critical_section();
}
#endif
/* Then restore the correct state for this thread of execution.
* NOTE: The co-processor state should already be correct.
*/