Re: [dpdk-dev] [PATCH v2 3/4] test: change memory barrier variables to uint64_t

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of David Christensen
> Sent: Monday, May 6, 2019 8:24 PM
> To: dev@dpdk.org
> Cc: David Christensen <drc@linux.vnet.ibm.com>
> Subject: [dpdk-dev] [PATCH v2 3/4] test: change memory barrier variables to uint64_t
> 
> Memory barrier failures can be intermittent. Increase the size of the
> sum/val/iteration variables to allow tests that can run for days so that
> sporadic errors can be identified.
> 
> Signed-off-by: David Christensen <drc@linux.vnet.ibm.com>
> ---
> v2:
> * Removed change to ITER_MAX
> 
>  app/test/test_barrier.c | 23 ++++++++++++-----------
>  1 file changed, 12 insertions(+), 11 deletions(-)
> 
> diff --git a/app/test/test_barrier.c b/app/test/test_barrier.c
> index ae37b1e..a022708 100644
> --- a/app/test/test_barrier.c
> +++ b/app/test/test_barrier.c
> @@ -55,8 +55,8 @@ struct plock {
>   */
>  struct plock_test {
>  	struct plock lock;
> -	uint32_t val;
> -	uint32_t iter;
> +	uint64_t val;
> +	uint64_t iter;
>  };
> 
>  /*
> @@ -65,8 +65,8 @@ struct plock_test {
>   */
>  struct lcore_plock_test {
>  	struct plock_test *pt[2]; /* shared, lock-protected data */
> -	uint32_t sum[2];          /* local copy of the shared data */
> -	uint32_t iter;            /* number of iterations to perfom */
> +	uint64_t sum[2];          /* local copy of the shared data */
> +	uint64_t iter;            /* number of iterations to perfom */
>  	uint32_t lc;              /* given lcore id */
>  };

Not sure why you think this is needed - right now
both iter and sum wouldn't be bigger than 32bit
(max value that sum can reach: 2^27).

> 
> @@ -130,7 +130,8 @@ struct lcore_plock_test {
>  plock_test1_lcore(void *data)
>  {
>  	uint64_t tm;
> -	uint32_t i, lc, ln, n;
> +	uint32_t lc, ln;
> +	uint64_t i, n;
>  	struct lcore_plock_test *lpt;
> 
>  	lpt = data;
> @@ -166,9 +167,9 @@ struct lcore_plock_test {
> 
>  	tm = rte_get_timer_cycles() - tm;
> 
> -	printf("%s(%u): %u iterations finished, in %" PRIu64
> +	printf("%s(%u): %lu iterations finished, in %" PRIu64
>  		" cycles, %#Lf cycles/iteration, "
> -		"local sum={%u, %u}\n",
> +		"local sum={%lu, %lu}\n",
>  		__func__, lc, i, tm, (long double)tm / i,
>  		lpt->sum[0], lpt->sum[1]);
>  	return 0;
> @@ -184,11 +185,11 @@ struct lcore_plock_test {
>   * and local data are the same.
>   */
>  static int
> -plock_test(uint32_t iter, enum plock_use_type utype)
> +plock_test(uint64_t iter, enum plock_use_type utype)
>  {
>  	int32_t rc;
>  	uint32_t i, lc, n;
> -	uint32_t *sum;
> +	uint64_t *sum;
>  	struct plock_test *pt;
>  	struct lcore_plock_test *lpt;
> 
> @@ -199,7 +200,7 @@ struct lcore_plock_test {
>  	lpt = calloc(n, sizeof(*lpt));
>  	sum = calloc(n + 1, sizeof(*sum));
> 
> -	printf("%s(iter=%u, utype=%u) started on %u lcores\n",
> +	printf("%s(iter=%lu, utype=%u) started on %u lcores\n",
>  		__func__, iter, utype, n);
> 
>  	if (pt == NULL || lpt == NULL || sum == NULL) {
> @@ -247,7 +248,7 @@ struct lcore_plock_test {
> 
>  	rc = 0;
>  	for (i = 0; i != n; i++) {
> -		printf("%s: sum[%u]=%u, pt[%u].val=%u, pt[%u].iter=%u;\n",
> +		printf("%s: sum[%u]=%lu, pt[%u].val=%lu, pt[%u].iter=%lu;\n",

Here and in other places, you need to use PRIu64 for 64 bit values.

>  			__func__, i, sum[i], i, pt[i].val, i, pt[i].iter);
> 
>  		/* race condition occurred, lock doesn't work properly */
> --
> 1.8.3.1