Re: [dpdk-stable] [EXT] [dpdk-dev] [PATCH v2 1/1] app/test: collect perf data after worker threads exit

[Pavan Nikhilesh Bhagavatula <pbhagavatula@marvell.com>]

>The measure_perf function should be executed after worker threads
>exit
>to collect correct perf data. Otherwise, while workers are running, the
>main thread may get incomplete data from workers.
>
>In the meanwhile, remove unnecessary barrier in the test.
>For signal variables "ldata.done" and "ldata.start", no operations
>should keep the order that being executed after them. So the wmb after
>them can be moved.
>
>Fixes: 16a277a24c9f ("test/trace: add performance test cases")
>Cc: jerinj@marvell.com
>Cc: stable@dpdk.org
>
>Suggested-by: Honnappa Nagarahalli
><honnappa.nagarahalli@arm.com>
>Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
>Reviewed-by: Honnappa Nagarahalli
><Honnappa.Nagarahalli@arm.com>
>Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>

Acked-by: Pavan Nikhilesh <pbhagavatula@marvell.com>

>---
> app/test/test_trace_perf.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
>diff --git a/app/test/test_trace_perf.c b/app/test/test_trace_perf.c
>index e1ad8e6f5..46ae7d807 100644
>--- a/app/test/test_trace_perf.c
>+++ b/app/test/test_trace_perf.c
>@@ -79,7 +79,6 @@ signal_workers_to_finish(struct test_data *data)
>
> 	for (workers = 0; workers < data->nb_workers; workers++) {
> 		data->ldata[workers].done = 1;
>-		rte_smp_wmb();
> 	}
> }
>
>@@ -102,7 +101,6 @@ worker_fn_##func(void *arg) \
> { \
> 	struct lcore_data *ldata = arg; \
> 	ldata->started = 1; \
>-	rte_smp_wmb(); \
> 	__worker_##func(ldata); \
> 	return 0; \
> }
>@@ -137,11 +135,12 @@ run_test(const char *str, lcore_function_t f,
>struct test_data *data, size_t sz)
>
> 	wait_till_workers_are_ready(data);
> 	rte_delay_ms(100); /* Wait for some time to accumulate the
>stats */
>-	measure_perf(str, data);
> 	signal_workers_to_finish(data);
>
> 	RTE_LCORE_FOREACH_WORKER(id)
> 		rte_eal_wait_lcore(id);
>+
>+	measure_perf(str, data);
> }
>
> static int
>--
>2.25.1