Re: [libevl][PATCH] tests: sched-quota: Simplify disruption

[Philippe Gerum <rpm@xenomai.org>]

Jan Kiszka <jan.kiszka@siemens.com> writes:

> From: Jan Kiszka <jan.kiszka@siemens.com>
>
> No need to spawn an extra thread here and also play ping-pong with it to
> generate an oscillating load. The main thread can do the very same thing
> within a few lines of code.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>
> On top of my previous patches.
>
>  tests/sched-quota-accuracy.c | 52 +++---------------------------------
>  1 file changed, 3 insertions(+), 49 deletions(-)
>
> diff --git a/tests/sched-quota-accuracy.c b/tests/sched-quota-accuracy.c
> index ac04449..251ea30 100644
> --- a/tests/sched-quota-accuracy.c
> +++ b/tests/sched-quota-accuracy.c
> @@ -26,15 +26,13 @@
>  
>  #define MAX_THREADS	8
>  #define QUOTA_PRIO	1
> -#define DISRUPTOR_PRIO	2
> -#define MAIN_PRIO	3
> +#define MAIN_PRIO	2
>  
>  enum runtime_phase {
>  	idle_phase,
>  	calibration_phase,
>  	accuracy_measurement_phase,
>  	noise_measurement_phase,
> -	disruption_phase,
>  } current_phase = idle_phase;
>  
>  static struct quota_thread_desc {
> @@ -111,23 +109,6 @@ static void wait_phase(enum runtime_phase phase)
>  	__Tcall_assert(ret, evl_unlock_mutex(&lock));
>  }
>  
> -static void wait_edge(enum runtime_phase phase)
> -{
> -	enum runtime_phase old_phase = phase;
> -	int ret;
> -
> -	__Tcall_assert(ret, evl_lock_mutex(&lock));
> -	for (;;) {
> -		if (current_phase == phase) {
> -			current_phase = old_phase;
> -			break;
> -		}
> -		old_phase = current_phase;
> -		__Tcall_assert(ret, evl_wait_event(&barrier, &lock));
> -	}
> -	__Tcall_assert(ret, evl_unlock_mutex(&lock));
> -}
> -
>  static void start_phase(enum runtime_phase phase)
>  {
>  	int ret;
> @@ -191,24 +172,6 @@ static void *quota_thread(void *arg)
>  	return NULL;
>  }
>  
> -static void *disruptor_thread(void *arg)
> -{
> -	int ret;
> -
> -	__Tcall_assert(ret, evl_attach_self("quota-disruptor:%d", getpid()));
> -
> -	wait_phase(noise_measurement_phase);
> -
> -	for (;;) {
> -		wait_edge(disruption_phase);
> -		do_trace("(...disrupting...)");
> -		do_work(NULL, DISRUPT_NS);
> -		start_phase(noise_measurement_phase);
> -	}
> -
> -	return NULL;
> -}
> -
>  static int cleanup_group(void)
>  {
>  	union evl_sched_ctlparam p;
> @@ -236,7 +199,6 @@ static struct accuracy_results run_quota(void)
>  	union evl_sched_ctlparam p;
>  	union evl_sched_ctlinfo q;
>  	struct timespec now, next;
> -	pthread_t disruptor;
>  	struct sigaction sa;
>  	int ret, n;
>  
> @@ -304,10 +266,6 @@ static struct accuracy_results run_quota(void)
>  
>  	do_trace("CPU%d: starting noise measurement", test_cpu);
>  
> -	/* Start the disruptor thread then wait for sync. */
> -	new_thread(&disruptor, SCHED_FIFO, DISRUPTOR_PRIO, disruptor_thread, NULL);
> -	__Tcall_assert(ret, evl_get_sem(&ready));
> -
>  	reset_quota_period(PERIOD_NS);
>  	start_phase(noise_measurement_phase);
>  
> @@ -316,17 +274,13 @@ static struct accuracy_results run_quota(void)
>  		evl_read_clock(EVL_CLOCK_MONOTONIC, &now);
>  		timespec_add_ns(&next, &now, DISRUPT_NS);
>  		__Tcall_assert(ret, evl_sleep_until(EVL_CLOCK_MONOTONIC, &next));
> -		start_phase(disruption_phase);
> -		wait_phase(noise_measurement_phase);
> -		__Tcall_assert(ret, evl_get_sem(&ready));
> +		do_trace("(...disrupting...)");
> +		do_work(NULL, DISRUPT_NS);
>  	}
>  
>  	for (n = 0; n < nrthreads; n++)
>  		pthread_join(threads[n].tid, NULL);
>  
> -	pthread_cancel(disruptor);
> -	pthread_join(disruptor, NULL);
> -
>  	for (n = 0, loops_with_disruption = 0; n < nrthreads; n++) {
>  		loops_with_disruption += threads[n].loops;
>  		do_trace("CPU%d: noise: quota_thread[%d]: loops=%llu",

Merged, thanks.

-- 
Philippe.