Re: [dpdk-dev] [PATCH v7 10/17] test/ring: modify single element enq/deq perf test cases

[Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>]

<snip>

> 
> >
> > Add test cases to test rte_ring_xxx_elem APIs for single element
> > enqueue/dequeue test cases.
> >
> > Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> > Reviewed-by: Gavin Hu <gavin.hu@arm.com>
> > ---
> >  app/test/test_ring_perf.c | 100
> > ++++++++++++++++++++++++++++++--------
> >  1 file changed, 80 insertions(+), 20 deletions(-)
> >
> > diff --git a/app/test/test_ring_perf.c b/app/test/test_ring_perf.c
> > index 6c2aca483..5829718c1 100644
> > --- a/app/test/test_ring_perf.c
> > +++ b/app/test/test_ring_perf.c
> > @@ -13,6 +13,7 @@
> >  #include <string.h>
> >
> >  #include "test.h"
> > +#include "test_ring.h"
> >
> >  /*
> >   * Ring
> > @@ -41,6 +42,35 @@ struct lcore_pair {
> >
> >  static volatile unsigned lcore_count = 0;
> >
> > +static void
> > +test_ring_print_test_string(unsigned int api_type, int esize,
> > +	unsigned int bsz, double value)
> > +{
> > +	if (esize == -1)
> > +		printf("legacy APIs");
> > +	else
> > +		printf("elem APIs: element size %dB", esize);
> > +
> > +	if (api_type == TEST_RING_IGNORE_API_TYPE)
> > +		return;
> > +
> > +	if ((api_type & TEST_RING_N) == TEST_RING_N)
> > +		printf(": default enqueue/dequeue: ");
> > +	else if ((api_type & TEST_RING_S) == TEST_RING_S)
> > +		printf(": SP/SC: ");
> > +	else if ((api_type & TEST_RING_M) == TEST_RING_M)
> > +		printf(": MP/MC: ");
> > +
> > +	if ((api_type & TEST_RING_SL) == TEST_RING_SL)
> > +		printf("single: ");
> > +	else if ((api_type & TEST_RING_BL) == TEST_RING_BL)
> > +		printf("bulk (size: %u): ", bsz);
> > +	else if ((api_type & TEST_RING_BR) == TEST_RING_BR)
> > +		printf("burst (size: %u): ", bsz);
> > +
> > +	printf("%.2F\n", value);
> > +}
> > +
> >  /**** Functions to analyse our core mask to get cores for different
> > tests ***/
> >
> >  static int
> > @@ -335,32 +365,35 @@ run_on_all_cores(struct rte_ring *r)
> >   * Test function that determines how long an enqueue + dequeue of a
> single item
> >   * takes on a single lcore. Result is for comparison with the bulk enq+deq.
> >   */
> > -static void
> > -test_single_enqueue_dequeue(struct rte_ring *r)
> > +static int
> > +test_single_enqueue_dequeue(struct rte_ring *r, const int esize,
> > +	const unsigned int api_type)
> >  {
> > -	const unsigned iter_shift = 24;
> > -	const unsigned iterations = 1<<iter_shift;
> > -	unsigned i = 0;
> > +	int ret;
> > +	const unsigned int iter_shift = 24;
> > +	const unsigned int iterations = 1 << iter_shift;
> > +	unsigned int i = 0;
> >  	void *burst = NULL;
> >
> > -	const uint64_t sc_start = rte_rdtsc();
> > -	for (i = 0; i < iterations; i++) {
> > -		rte_ring_sp_enqueue(r, burst);
> > -		rte_ring_sc_dequeue(r, &burst);
> > -	}
> > -	const uint64_t sc_end = rte_rdtsc();
> > +	(void)ret;
> 
> Here, and in few other places, looks redundant.
The compiler throws an error since 'ret' is assigned a value, but it is not used.

> 
> > +	/* alloc dummy object pointers */
> > +	burst = test_ring_calloc(1, esize);
> > +	if (burst == NULL)
> > +		return -1;
> >
> > -	const uint64_t mc_start = rte_rdtsc();
> > +	const uint64_t start = rte_rdtsc();
> >  	for (i = 0; i < iterations; i++) {
> > -		rte_ring_mp_enqueue(r, burst);
> > -		rte_ring_mc_dequeue(r, &burst);
> > +		TEST_RING_ENQUEUE(r, burst, esize, 1, ret, api_type);
> > +		TEST_RING_DEQUEUE(r, burst, esize, 1, ret, api_type);
> >  	}
> > -	const uint64_t mc_end = rte_rdtsc();
> > +	const uint64_t end = rte_rdtsc();
> > +
> > +	test_ring_print_test_string(api_type, esize, 1,
> > +					((double)(end - start)) / iterations);
> > +
> > +	rte_free(burst);
> >
> > -	printf("SP/SC single enq/dequeue: %.2F\n",
> > -			((double)(sc_end-sc_start)) / iterations);
> > -	printf("MP/MC single enq/dequeue: %.2F\n",
> > -			((double)(mc_end-mc_start)) / iterations);
> > +	return 0;
> >  }
> >
> >  /*