[PATCH V2 1/5] cobalt/tick: dovetail: implement pipeline_set_timer_shot to trigger tick shot

[PATCH V2 1/5] cobalt/tick: dovetail: implement pipeline_set_timer_shot to trigger tick shot

[hongzha1]

Signed-off-by: hongzha1 <hongzhan.chen@intel.com>

diff --git a/include/cobalt/kernel/dovetail/pipeline/clock.h b/include/cobalt/kernel/dovetail/pipeline/clock.h
index 28d89b44b..7b6ce161c 100644
--- a/include/cobalt/kernel/dovetail/pipeline/clock.h
+++ b/include/cobalt/kernel/dovetail/pipeline/clock.h
@@ -17,17 +17,7 @@ static inline u64 pipeline_read_cycle_counter(void)
 	return  ktime_get_raw_fast_ns();
 }
 
-static inline void pipeline_set_timer_shot(unsigned long cycles)
-{
-	/*
-	 * N/A. Revisit: xnclock_core_local_shot() should go to the
-	 * I-pipe section, we do things differently on Dovetail via
-	 * the proxy tick device. As a consequence,
-	 * pipeline_set_timer_shot() should not be part of the
-	 * pipeline interface.
-	 */
-	TODO();
-}
+void pipeline_set_timer_shot(unsigned long cycles);
 
 static inline const char *pipeline_timer_name(void)
 {
diff --git a/kernel/cobalt/dovetail/tick.c b/kernel/cobalt/dovetail/tick.c
index 6a196496c..75d908bd4 100644
--- a/kernel/cobalt/dovetail/tick.c
+++ b/kernel/cobalt/dovetail/tick.c
@@ -16,6 +16,36 @@ extern struct xnintr nktimer;
 
 static DEFINE_PER_CPU(struct clock_proxy_device *, proxy_device);
 
+void pipeline_set_timer_shot(unsigned long cycles)
+{
+	struct clock_proxy_device *dev = __this_cpu_read(proxy_device);
+	struct clock_event_device *real_dev = dev->real_device;
+	int ret;
+	u64 sumcyc;
+	ktime_t t;
+
+	if (real_dev->features & CLOCK_EVT_FEAT_KTIME) {
+		t = ktime_add(cycles, xnclock_core_read_raw());
+		real_dev->set_next_ktime(t, real_dev);
+	} else {
+		if (cycles <= 0)
+			cycles = real_dev->min_delta_ns;
+		else {
+			cycles = min_t(int64_t, cycles,
+					real_dev->max_delta_ns);
+			cycles = max_t(int64_t, cycles,
+					real_dev->min_delta_ns);
+		}
+		sumcyc = ((u64)cycles * real_dev->mult) >> real_dev->shift;
+
+		ret = real_dev->set_next_event(sumcyc, real_dev);
+		if (ret) {
+			ret = real_dev->set_next_event(real_dev->min_delta_ticks,
+							real_dev);
+		}
+	}
+}
+
 static int proxy_set_next_ktime(ktime_t expires,
 				struct clock_event_device *proxy_dev)
 {
-- 
2.17.1

[PATCH V2 2/5] cobalt/tick: dovetail: implement pipeline_timer_name

[hongzha1]

Get the name of real device controlled by the proxy tick device.

Signed-off-by: hongzha1 <hongzhan.chen@intel.com>

diff --git a/include/cobalt/kernel/dovetail/pipeline/clock.h b/include/cobalt/kernel/dovetail/pipeline/clock.h
index 7b6ce161c..6761ed70d 100644
--- a/include/cobalt/kernel/dovetail/pipeline/clock.h
+++ b/include/cobalt/kernel/dovetail/pipeline/clock.h
@@ -19,16 +19,7 @@ static inline u64 pipeline_read_cycle_counter(void)
 
 void pipeline_set_timer_shot(unsigned long cycles);
 
-static inline const char *pipeline_timer_name(void)
-{
-	/*
-	 * Return the name of the current clock event chip, which is
-	 * the real device controlled by the proxy tick device.
-	 */
-	TODO();
-
-	return "?";
-}
+const char *pipeline_timer_name(void);
 
 static inline const char *pipeline_clock_name(void)
 {
diff --git a/kernel/cobalt/dovetail/tick.c b/kernel/cobalt/dovetail/tick.c
index 75d908bd4..1b622defb 100644
--- a/kernel/cobalt/dovetail/tick.c
+++ b/kernel/cobalt/dovetail/tick.c
@@ -16,6 +16,18 @@ extern struct xnintr nktimer;
 
 static DEFINE_PER_CPU(struct clock_proxy_device *, proxy_device);
 
+const char *pipeline_timer_name(void)
+{
+	struct clock_proxy_device *dev = __this_cpu_read(proxy_device);
+	struct clock_event_device *real_dev = dev->real_device;
+
+	/*
+	 * Return the name of the current clock event chip, which is
+	 * the real device controlled by the proxy tick device.
+	 */
+	return real_dev->name;
+}
+
 void pipeline_set_timer_shot(unsigned long cycles)
 {
 	struct clock_proxy_device *dev = __this_cpu_read(proxy_device);
-- 
2.17.1

[PATCH V2 3/5] dovetail/kevents: dovetail: implement handle_ptrace_cont

[hongzha1]

Signed-off-by: hongzha1 <hongzhan.chen@intel.com>

diff --git a/kernel/cobalt/dovetail/kevents.c b/kernel/cobalt/dovetail/kevents.c
index 6aec170d1..0528e2938 100644
--- a/kernel/cobalt/dovetail/kevents.c
+++ b/kernel/cobalt/dovetail/kevents.c
@@ -480,7 +480,75 @@ static void handle_ptrace_cont(void)
 	 * stopped state, which is what look for in
 	 * handle_schedule_event().
 	 */
-	TODO();
+	struct task_struct *next_task;
+	struct xnthread *next;
+	sigset_t pending;
+	spl_t s;
+
+	cobalt_signal_yield();
+
+	next_task = current;
+	next = xnthread_from_task(next_task);
+	if (next == NULL)
+		return;
+
+	xnlock_get_irqsave(&nklock, s);
+
+	/*
+	 * Track tasks leaving the ptraced state.  Check both SIGSTOP
+	 * (NPTL) and SIGINT (LinuxThreads) to detect ptrace
+	 * continuation.
+	 */
+	if (xnthread_test_state(next, XNSSTEP)) {
+		if (signal_pending(next_task)) {
+			/*
+			 * Do not grab the sighand lock here: it's
+			 * useless, and we already own the runqueue
+			 * lock, so this would expose us to deadlock
+			 * situations on SMP.
+			 */
+			sigorsets(&pending,
+				  &next_task->pending.signal,
+				  &next_task->signal->shared_pending.signal);
+			if (sigismember(&pending, SIGSTOP) ||
+			    sigismember(&pending, SIGINT))
+				goto no_ptrace;
+		}
+
+		/*
+		 * Do not unregister before the thread migrated.
+		 * unregister_debugged_thread will then be called by our
+		 * resume_oob_task.
+		 */
+		if (!xnthread_test_info(next, XNCONTHI))
+			unregister_debugged_thread(next);
+
+		xnthread_set_localinfo(next, XNHICCUP);
+	}
+
+no_ptrace:
+	xnlock_put_irqrestore(&nklock, s);
+
+	/*
+	 * Do basic sanity checks on the incoming thread state.
+	 * NOTE: we allow ptraced threads to run shortly in order to
+	 * properly recover from a stopped state.
+	 */
+	if (!XENO_WARN(COBALT, !xnthread_test_state(next, XNRELAX),
+		       "hardened thread %s[%d] running in Linux domain?! "
+		       "(status=0x%x, sig=%d)",
+		       next->name, task_pid_nr(next_task),
+		       xnthread_get_state(next),
+		       signal_pending(next_task)))
+		XENO_WARN(COBALT,
+			  !(next_task->ptrace & PT_PTRACED) &&
+			   !xnthread_test_state(next, XNDORMANT)
+			  && xnthread_test_state(next, XNPEND),
+			  "blocked thread %s[%d] rescheduled?! "
+			  "(status=0x%x, sig=%d)",
+			  next->name, task_pid_nr(next_task),
+			  xnthread_get_state(next),
+			  signal_pending(next_task));
 }
 
 void handle_inband_event(enum inband_event_type event, void *data)
-- 
2.17.1

[PATCH V2 4/5] cobalt/timer: pipeline: abstract signal test of XNTSTOP

[hongzha1]

It adds a way to force the timer management code to reprogram the
hardware on option, to make the real device controlled by the proxy
tick again as it leaves the ONESHOT_STOPPED mode. The I-pipe does not
require any further action in this case, leading to a nop.

Signed-off-by: hongzha1 <hongzhan.chen@intel.com>

diff --git a/include/cobalt/kernel/ipipe/pipeline/tick.h b/include/cobalt/kernel/ipipe/pipeline/tick.h
index 409581a3c..41347f7b1 100644
--- a/include/cobalt/kernel/ipipe/pipeline/tick.h
+++ b/include/cobalt/kernel/ipipe/pipeline/tick.h
@@ -9,4 +9,10 @@ int pipeline_install_tick_proxy(void);
 
 void pipeline_uninstall_tick_proxy(void);
 
+struct xnsched;
+static inline bool pipeline_must_force_program_tick(struct xnsched *sched)
+{
+	return false;
+}
+
 #endif /* !_COBALT_KERNEL_IPIPE_TICK_H */
diff --git a/include/cobalt/kernel/sched.h b/include/cobalt/kernel/sched.h
index c13f46ff7..aa24d5442 100644
--- a/include/cobalt/kernel/sched.h
+++ b/include/cobalt/kernel/sched.h
@@ -48,6 +48,11 @@
 #define XNINIRQ		0x00004000	/* In IRQ handling context */
 #define XNHDEFER	0x00002000	/* Host tick deferred */
 
+/*
+ * Hardware timer is stopped.
+ */
+#define XNTSTOP		0x00000800
+
 struct xnsched_rt {
 	xnsched_queue_t runnable;	/*!< Runnable thread queue. */
 };
diff --git a/kernel/cobalt/clock.c b/kernel/cobalt/clock.c
index bf24e1693..2115b15ef 100644
--- a/kernel/cobalt/clock.c
+++ b/kernel/cobalt/clock.c
@@ -147,7 +147,7 @@ void xnclock_core_local_shot(struct xnsched *sched)
 	 * or a timer with an earlier timeout date is scheduled,
 	 * whichever comes first.
 	 */
-	sched->lflags &= ~(XNHDEFER|XNIDLE);
+	sched->lflags &= ~(XNHDEFER|XNIDLE|XNTSTOP);
 	timer = container_of(h, struct xntimer, aplink);
 	if (unlikely(timer == &sched->htimer)) {
 		if (xnsched_resched_p(sched) ||
diff --git a/kernel/cobalt/timer.c b/kernel/cobalt/timer.c
index f9aa457ce..f667a3878 100644
--- a/kernel/cobalt/timer.c
+++ b/kernel/cobalt/timer.c
@@ -18,6 +18,7 @@
  * 02111-1307, USA.
  */
 #include <linux/sched.h>
+#include <pipeline/tick.h>
 #include <cobalt/kernel/sched.h>
 #include <cobalt/kernel/thread.h>
 #include <cobalt/kernel/timer.h>
@@ -63,8 +64,10 @@ int xntimer_heading_p(struct xntimer *timer)
 
 void xntimer_enqueue_and_program(struct xntimer *timer, xntimerq_t *q)
 {
+	struct xnsched *sched = xntimer_sched(timer);
+
 	xntimer_enqueue(timer, q);
-	if (xntimer_heading_p(timer)) {
+	if (pipeline_must_force_program_tick(sched) || xntimer_heading_p(timer)) {
 		struct xnsched *sched = xntimer_sched(timer);
 		struct xnclock *clock = xntimer_clock(timer);
 		if (sched != xnsched_current())
-- 
2.17.1

[PATCH V2 5/5] dovetail/tick: pipeline: implement pipeline_must_force_program_tick

[hongzha1]

Force the next tick to be programmed in the hardware as a result of
leaving the ONESHOT_STOPPED

Signed-off-by: hongzha1 <hongzhan.chen@intel.com>

diff --git a/include/cobalt/kernel/dovetail/pipeline/tick.h b/include/cobalt/kernel/dovetail/pipeline/tick.h
index 409581a3c..8ac4760ec 100644
--- a/include/cobalt/kernel/dovetail/pipeline/tick.h
+++ b/include/cobalt/kernel/dovetail/pipeline/tick.h
@@ -9,4 +9,8 @@ int pipeline_install_tick_proxy(void);
 
 void pipeline_uninstall_tick_proxy(void);
 
+struct xnsched;
+
+inline bool pipeline_must_force_program_tick(struct xnsched *sched);
+
 #endif /* !_COBALT_KERNEL_IPIPE_TICK_H */
diff --git a/kernel/cobalt/dovetail/tick.c b/kernel/cobalt/dovetail/tick.c
index 1b622defb..fc6203667 100644
--- a/kernel/cobalt/dovetail/tick.c
+++ b/kernel/cobalt/dovetail/tick.c
@@ -89,6 +89,11 @@ void xn_core_tick(struct clock_event_device *dummy) /* hard irqs off */
 	xnintr_core_clock_handler();
 }
 
+inline bool pipeline_must_force_program_tick(struct xnsched *sched)
+{
+	return sched->lflags & XNTSTOP;
+}
+
 static int proxy_set_oneshot_stopped(struct clock_event_device *proxy_dev)
 {
 	struct clock_event_device *real_dev;
@@ -110,7 +115,7 @@ static int proxy_set_oneshot_stopped(struct clock_event_device *proxy_dev)
 	xnlock_get_irqsave(&nklock, s);
 	sched = xnsched_current();
 	xntimer_stop(&sched->htimer);
-	//sched->lflags |= XNTSTOP;
+	sched->lflags |= XNTSTOP;
 
 	if (sched->lflags & XNIDLE) {
 		real_dev = dev->real_device;
-- 
2.17.1

Re: [PATCH V2 1/5] cobalt/tick: dovetail: implement pipeline_set_timer_shot to trigger tick shot

[Philippe Gerum]

hongzha1 via Xenomai <xenomai@xenomai.org> writes:

> Signed-off-by: hongzha1 <hongzhan.chen@intel.com>
>
> diff --git a/include/cobalt/kernel/dovetail/pipeline/clock.h b/include/cobalt/kernel/dovetail/pipeline/clock.h
> index 28d89b44b..7b6ce161c 100644
> --- a/include/cobalt/kernel/dovetail/pipeline/clock.h
> +++ b/include/cobalt/kernel/dovetail/pipeline/clock.h
> @@ -17,17 +17,7 @@ static inline u64 pipeline_read_cycle_counter(void)
>  	return  ktime_get_raw_fast_ns();
>  }
>  
> -static inline void pipeline_set_timer_shot(unsigned long cycles)
> -{
> -	/*
> -	 * N/A. Revisit: xnclock_core_local_shot() should go to the
> -	 * I-pipe section, we do things differently on Dovetail via
> -	 * the proxy tick device. As a consequence,
> -	 * pipeline_set_timer_shot() should not be part of the
> -	 * pipeline interface.
> -	 */
> -	TODO();
> -}
> +void pipeline_set_timer_shot(unsigned long cycles);
>  
>  static inline const char *pipeline_timer_name(void)
>  {
> diff --git a/kernel/cobalt/dovetail/tick.c b/kernel/cobalt/dovetail/tick.c
> index 6a196496c..75d908bd4 100644
> --- a/kernel/cobalt/dovetail/tick.c
> +++ b/kernel/cobalt/dovetail/tick.c
> @@ -16,6 +16,36 @@ extern struct xnintr nktimer;
>  
>  static DEFINE_PER_CPU(struct clock_proxy_device *, proxy_device);
>  
> +void pipeline_set_timer_shot(unsigned long cycles)
> +{
> +	struct clock_proxy_device *dev = __this_cpu_read(proxy_device);
> +	struct clock_event_device *real_dev = dev->real_device;
> +	int ret;
> +	u64 sumcyc;
> +	ktime_t t;
> +
> +	if (real_dev->features & CLOCK_EVT_FEAT_KTIME) {
> +		t = ktime_add(cycles, xnclock_core_read_raw());
> +		real_dev->set_next_ktime(t, real_dev);
> +	} else {
> +		if (cycles <= 0)
> +			cycles = real_dev->min_delta_ns;
> +		else {
> +			cycles = min_t(int64_t, cycles,
> +					real_dev->max_delta_ns);
> +			cycles = max_t(int64_t, cycles,
> +					real_dev->min_delta_ns);
> +		}
> +		sumcyc = ((u64)cycles * real_dev->mult) >> real_dev->shift;
> +
> +		ret = real_dev->set_next_event(sumcyc, real_dev);
> +		if (ret) {
> +			ret = real_dev->set_next_event(real_dev->min_delta_ticks,
> +							real_dev);
> +		}
> +	}
> +}
> +
>  static int proxy_set_next_ktime(ktime_t expires,
>  				struct clock_event_device *proxy_dev)
>  {

Merged, thanks.

-- 
Philippe.

Re: [PATCH V2 2/5] cobalt/tick: dovetail: implement pipeline_timer_name

[Philippe Gerum]

hongzha1 via Xenomai <xenomai@xenomai.org> writes:

> Get the name of real device controlled by the proxy tick device.
>
> Signed-off-by: hongzha1 <hongzhan.chen@intel.com>
>
> diff --git a/include/cobalt/kernel/dovetail/pipeline/clock.h b/include/cobalt/kernel/dovetail/pipeline/clock.h
> index 7b6ce161c..6761ed70d 100644
> --- a/include/cobalt/kernel/dovetail/pipeline/clock.h
> +++ b/include/cobalt/kernel/dovetail/pipeline/clock.h
> @@ -19,16 +19,7 @@ static inline u64 pipeline_read_cycle_counter(void)
>  
>  void pipeline_set_timer_shot(unsigned long cycles);
>  
> -static inline const char *pipeline_timer_name(void)
> -{
> -	/*
> -	 * Return the name of the current clock event chip, which is
> -	 * the real device controlled by the proxy tick device.
> -	 */
> -	TODO();
> -
> -	return "?";
> -}
> +const char *pipeline_timer_name(void);
>  
>  static inline const char *pipeline_clock_name(void)
>  {
> diff --git a/kernel/cobalt/dovetail/tick.c b/kernel/cobalt/dovetail/tick.c
> index 75d908bd4..1b622defb 100644
> --- a/kernel/cobalt/dovetail/tick.c
> +++ b/kernel/cobalt/dovetail/tick.c
> @@ -16,6 +16,18 @@ extern struct xnintr nktimer;
>  
>  static DEFINE_PER_CPU(struct clock_proxy_device *, proxy_device);
>  
> +const char *pipeline_timer_name(void)
> +{
> +	struct clock_proxy_device *dev = __this_cpu_read(proxy_device);
> +	struct clock_event_device *real_dev = dev->real_device;
> +
> +	/*
> +	 * Return the name of the current clock event chip, which is
> +	 * the real device controlled by the proxy tick device.
> +	 */
> +	return real_dev->name;
> +}
> +
>  void pipeline_set_timer_shot(unsigned long cycles)
>  {
>  	struct clock_proxy_device *dev = __this_cpu_read(proxy_device);

Merged, thanks.

-- 
Philippe.

Re: [PATCH V2 4/5] cobalt/timer: pipeline: abstract signal test of XNTSTOP

[Philippe Gerum]

hongzha1 via Xenomai <xenomai@xenomai.org> writes:

> It adds a way to force the timer management code to reprogram the
> hardware on option, to make the real device controlled by the proxy
> tick again as it leaves the ONESHOT_STOPPED mode. The I-pipe does not
> require any further action in this case, leading to a nop.
>
> Signed-off-by: hongzha1 <hongzhan.chen@intel.com>
>
> diff --git a/include/cobalt/kernel/ipipe/pipeline/tick.h b/include/cobalt/kernel/ipipe/pipeline/tick.h
> index 409581a3c..41347f7b1 100644
> --- a/include/cobalt/kernel/ipipe/pipeline/tick.h
> +++ b/include/cobalt/kernel/ipipe/pipeline/tick.h
> @@ -9,4 +9,10 @@ int pipeline_install_tick_proxy(void);
>  
>  void pipeline_uninstall_tick_proxy(void);
>  
> +struct xnsched;
> +static inline bool pipeline_must_force_program_tick(struct xnsched *sched)
> +{
> +	return false;
> +}
> +
>  #endif /* !_COBALT_KERNEL_IPIPE_TICK_H */
> diff --git a/include/cobalt/kernel/sched.h b/include/cobalt/kernel/sched.h
> index c13f46ff7..aa24d5442 100644
> --- a/include/cobalt/kernel/sched.h
> +++ b/include/cobalt/kernel/sched.h
> @@ -48,6 +48,11 @@
>  #define XNINIRQ		0x00004000	/* In IRQ handling context */
>  #define XNHDEFER	0x00002000	/* Host tick deferred */
>  
> +/*
> + * Hardware timer is stopped.
> + */
> +#define XNTSTOP		0x00000800
> +
>  struct xnsched_rt {
>  	xnsched_queue_t runnable;	/*!< Runnable thread queue. */
>  };
> diff --git a/kernel/cobalt/clock.c b/kernel/cobalt/clock.c
> index bf24e1693..2115b15ef 100644
> --- a/kernel/cobalt/clock.c
> +++ b/kernel/cobalt/clock.c
> @@ -147,7 +147,7 @@ void xnclock_core_local_shot(struct xnsched *sched)
>  	 * or a timer with an earlier timeout date is scheduled,
>  	 * whichever comes first.
>  	 */
> -	sched->lflags &= ~(XNHDEFER|XNIDLE);
> +	sched->lflags &= ~(XNHDEFER|XNIDLE|XNTSTOP);
>  	timer = container_of(h, struct xntimer, aplink);
>  	if (unlikely(timer == &sched->htimer)) {
>  		if (xnsched_resched_p(sched) ||
> diff --git a/kernel/cobalt/timer.c b/kernel/cobalt/timer.c
> index f9aa457ce..f667a3878 100644
> --- a/kernel/cobalt/timer.c
> +++ b/kernel/cobalt/timer.c
> @@ -18,6 +18,7 @@
>   * 02111-1307, USA.
>   */
>  #include <linux/sched.h>
> +#include <pipeline/tick.h>
>  #include <cobalt/kernel/sched.h>
>  #include <cobalt/kernel/thread.h>
>  #include <cobalt/kernel/timer.h>
> @@ -63,8 +64,10 @@ int xntimer_heading_p(struct xntimer *timer)
>  
>  void xntimer_enqueue_and_program(struct xntimer *timer, xntimerq_t *q)
>  {
> +	struct xnsched *sched = xntimer_sched(timer);
> +
>  	xntimer_enqueue(timer, q);
> -	if (xntimer_heading_p(timer)) {
> +	if (pipeline_must_force_program_tick(sched) || xntimer_heading_p(timer)) {
>  		struct xnsched *sched = xntimer_sched(timer);
>  		struct xnclock *clock = xntimer_clock(timer);
>  		if (sched != xnsched_current())

Merged, fixing up the short log. Thanks.

-- 
Philippe.

Re: [PATCH V2 5/5] dovetail/tick: pipeline: implement pipeline_must_force_program_tick

[Philippe Gerum]

hongzha1 via Xenomai <xenomai@xenomai.org> writes:

> Force the next tick to be programmed in the hardware as a result of
> leaving the ONESHOT_STOPPED
>
> Signed-off-by: hongzha1 <hongzhan.chen@intel.com>
>
> diff --git a/include/cobalt/kernel/dovetail/pipeline/tick.h b/include/cobalt/kernel/dovetail/pipeline/tick.h
> index 409581a3c..8ac4760ec 100644
> --- a/include/cobalt/kernel/dovetail/pipeline/tick.h
> +++ b/include/cobalt/kernel/dovetail/pipeline/tick.h
> @@ -9,4 +9,8 @@ int pipeline_install_tick_proxy(void);
>  
>  void pipeline_uninstall_tick_proxy(void);
>  
> +struct xnsched;
> +
> +inline bool pipeline_must_force_program_tick(struct xnsched *sched);
> +
>  #endif /* !_COBALT_KERNEL_IPIPE_TICK_H */
> diff --git a/kernel/cobalt/dovetail/tick.c b/kernel/cobalt/dovetail/tick.c
> index 1b622defb..fc6203667 100644
> --- a/kernel/cobalt/dovetail/tick.c
> +++ b/kernel/cobalt/dovetail/tick.c
> @@ -89,6 +89,11 @@ void xn_core_tick(struct clock_event_device *dummy) /* hard irqs off */
>  	xnintr_core_clock_handler();
>  }
>  
> +inline bool pipeline_must_force_program_tick(struct xnsched *sched)
> +{
> +	return sched->lflags & XNTSTOP;
> +}
> +
>  static int proxy_set_oneshot_stopped(struct clock_event_device *proxy_dev)
>  {
>  	struct clock_event_device *real_dev;
> @@ -110,7 +115,7 @@ static int proxy_set_oneshot_stopped(struct clock_event_device *proxy_dev)
>  	xnlock_get_irqsave(&nklock, s);
>  	sched = xnsched_current();
>  	xntimer_stop(&sched->htimer);
> -	//sched->lflags |= XNTSTOP;
> +	sched->lflags |= XNTSTOP;
>  
>  	if (sched->lflags & XNIDLE) {
>  		real_dev = dev->real_device;

Merged, fixing the short log. Thanks.

-- 
Philippe.

Re: [PATCH V2 3/5] dovetail/kevents: dovetail: implement handle_ptrace_cont

[Philippe Gerum]

hongzha1 via Xenomai <xenomai@xenomai.org> writes:

> Signed-off-by: hongzha1 <hongzhan.chen@intel.com>
>
> diff --git a/kernel/cobalt/dovetail/kevents.c b/kernel/cobalt/dovetail/kevents.c
> index 6aec170d1..0528e2938 100644
> --- a/kernel/cobalt/dovetail/kevents.c
> +++ b/kernel/cobalt/dovetail/kevents.c
> @@ -480,7 +480,75 @@ static void handle_ptrace_cont(void)
>  	 * stopped state, which is what look for in
>  	 * handle_schedule_event().
>  	 */
> -	TODO();
> +	struct task_struct *next_task;
> +	struct xnthread *next;
> +	sigset_t pending;
> +	spl_t s;
> +
> +	cobalt_signal_yield();
> +
> +	next_task = current;
> +	next = xnthread_from_task(next_task);
> +	if (next == NULL)
> +		return;
> +
> +	xnlock_get_irqsave(&nklock, s);
> +
> +	/*
> +	 * Track tasks leaving the ptraced state.  Check both SIGSTOP
> +	 * (NPTL) and SIGINT (LinuxThreads) to detect ptrace
> +	 * continuation.
> +	 */
> +	if (xnthread_test_state(next, XNSSTEP)) {
> +		if (signal_pending(next_task)) {
> +			/*
> +			 * Do not grab the sighand lock here: it's
> +			 * useless, and we already own the runqueue
> +			 * lock, so this would expose us to deadlock
> +			 * situations on SMP.
> +			 */
> +			sigorsets(&pending,
> +				  &next_task->pending.signal,
> +				  &next_task->signal->shared_pending.signal);
> +			if (sigismember(&pending, SIGSTOP) ||
> +			    sigismember(&pending, SIGINT))
> +				goto no_ptrace;
> +		}
> +
> +		/*
> +		 * Do not unregister before the thread migrated.
> +		 * unregister_debugged_thread will then be called by our
> +		 * resume_oob_task.
> +		 */
> +		if (!xnthread_test_info(next, XNCONTHI))
> +			unregister_debugged_thread(next);
> +
> +		xnthread_set_localinfo(next, XNHICCUP);
> +	}
> +

Since we know Dovetail just called us because 'current' is about to
resume from a stopped state, we don't need the hackish code above which
was aimed at determining whether next_task was about to do so
(i.e. resuming from ptrace stop).

> +no_ptrace:
> +	xnlock_put_irqrestore(&nklock, s);
> +
> +	/*
> +	 * Do basic sanity checks on the incoming thread state.
> +	 * NOTE: we allow ptraced threads to run shortly in order to
> +	 * properly recover from a stopped state.
> +	 */
> +	if (!XENO_WARN(COBALT, !xnthread_test_state(next, XNRELAX),
> +		       "hardened thread %s[%d] running in Linux domain?! "
> +		       "(status=0x%x, sig=%d)",
> +		       next->name, task_pid_nr(next_task),
> +		       xnthread_get_state(next),
> +		       signal_pending(next_task)))
> +		XENO_WARN(COBALT,
> +			  !(next_task->ptrace & PT_PTRACED) &&
> +			   !xnthread_test_state(next, XNDORMANT)
> +			  && xnthread_test_state(next, XNPEND),
> +			  "blocked thread %s[%d] rescheduled?! "
> +			  "(status=0x%x, sig=%d)",
> +			  next->name, task_pid_nr(next_task),
> +			  xnthread_get_state(next),
> +			  signal_pending(next_task));
>  }
>  
>  void handle_inband_event(enum inband_event_type event, void *data)

On second thought, we could also drop the remaining check above, since
what is being tested is a very basic Dovetail guarantee, i.e. that
'current' must be running in-band. IOW, receiving ptrace_cont should
lead to a nop when running on top of Dovetail.

-- 
Philippe.