From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joyce Kong Subject: [PATCH v4 3/3] test/rwlock: amortize the cost of getting time Date: Wed, 20 Mar 2019 14:25:09 +0800 Message-ID: <1553063109-57574-4-git-send-email-joyce.kong@arm.com> References: <1553063109-57574-1-git-send-email-joyce.kong@arm.com> Cc: nd@arm.com, jerinj@marvell.com, konstantin.ananyev@intel.com, chaozhu@linux.vnet.ibm.com, bruce.richardson@intel.com, thomas@monjalon.net, hemant.agrawal@nxp.com, honnappa.nagarahalli@arm.com, gavin.hu@arm.com, stable@dpdk.org To: dev@dpdk.org Return-path: In-Reply-To: <1553063109-57574-1-git-send-email-joyce.kong@arm.com> In-Reply-To: <1544672265-219262-2-git-send-email-joyce.kong@arm.com> References: <1544672265-219262-2-git-send-email-joyce.kong@arm.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Instead of getting timestamp per iteration, amortize its overhead can help to get more precise benchmarking results. Fixes: af75078fece3 ("first public release") Cc: stable@dpdk.org Signed-off-by: Joyce Kong Reviewed-by: Gavin Hu Reviewed-by: Ola Liljedahl Reviewed-by: Ruifeng Wang --- app/test/test_rwlock.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/app/test/test_rwlock.c b/app/test/test_rwlock.c index f1c5f40..48291c2 100644 --- a/app/test/test_rwlock.c +++ b/app/test/test_rwlock.c @@ -86,9 +86,9 @@ test_rwlock_per_core(__attribute__((unused)) void *arg) static rte_rwlock_t lk = RTE_RWLOCK_INITIALIZER; static volatile uint64_t rwlock_data; -static uint64_t lock_count[RTE_MAX_LCORE] = {0}; +static uint64_t time_count[RTE_MAX_LCORE] = {0}; -#define TIME_MS 100 +#define MAX_LOOP 10000 #define TEST_RWLOCK_DEBUG 0 static int @@ -105,7 +105,7 @@ load_loop_fn(__attribute__((unused)) void *arg) ; begin = rte_rdtsc_precise(); - while (time_diff < hz * TIME_MS / 1000) { + while (lcount < MAX_LOOP) { rte_rwlock_write_lock(&lk); ++rwlock_data; rte_rwlock_write_unlock(&lk); @@ -119,10 +119,10 @@ load_loop_fn(__attribute__((unused)) void *arg) lcount++; /* delay to make lock duty cycle slightly realistic */ rte_pause(); - time_diff = rte_rdtsc_precise() - begin; } - lock_count[lcore] = lcount; + time_diff = rte_rdtsc_precise() - begin; + time_count[lcore] = time_diff * 1000000 / hz; return 0; } @@ -146,11 +146,13 @@ test_rwlock_perf(void) rte_eal_mp_wait_lcore(); RTE_LCORE_FOREACH(i) { - printf("Core [%u] count = %"PRIu64"\n", i, lock_count[i]); - total += lock_count[i]; + printf("Core [%u] cost time = %"PRIu64" us\n", + i, time_count[i]); + total += time_count[i]; } - printf("Total count = %"PRIu64"\n", total); + printf("Total cost time = %"PRIu64" us\n", total); + memset(time_count, 0, sizeof(time_count)); return 0; } -- 2.7.4