Re: [dpdk-dev] [PATCH v2 1/2] test/hash: use existing lcore API

[Dharmik Thakkar <Dharmik.Thakkar@arm.com>]

Hi David,

Thank you for the patch!

Some comments inlined.

> On May 22, 2019, at 10:06 AM, David Marchand <david.marchand@redhat.com> wrote:
> 
> Prefer the existing apis rather than direct access the configuration
> structure.
> 
> test_hash_multi_add_lookup() currently starts n readers and N writers
> using rte_eal_remote_launch().
> It then waits for the N writers to complete with a custom
> multi_writer_done[] array to synchronise over.
> Jump on the occasion to use rte_eal_wait_lcore() so that the code is
> more straightforward:
> - we start n readers with rte_eal_remote_launch(),
> - we start N writers with rte_eal_remote_launch(),
> - we wait for N writers to join with rte_eal_wait_lcore(),
> - we wait for n readers to join with rte_eal_wait_lcore(),
> 
> Fixes: c7eb0972e74b ("test/hash: add lock-free r/w concurrency")
> Fixes: 3f9aab961ed3 ("test/hash: check lock-free extendable bucket")
> Cc: stable@dpdk.org
> 
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> ---
> app/test/test_hash_readwrite_lf.c | 41 ++++++++++++++++++---------------------
> 1 file changed, 19 insertions(+), 22 deletions(-)
> 
> ---
> Changelog since v1:
> - fixed test hang in test_hash_multi_add_lookup() reported by Wang, Yipeng
> 
> diff --git a/app/test/test_hash_readwrite_lf.c b/app/test/test_hash_readwrite_lf.c
> index 4ab4c8e..343a338 100644
> --- a/app/test/test_hash_readwrite_lf.c
> +++ b/app/test/test_hash_readwrite_lf.c
> @@ -86,7 +86,6 @@ struct {
> static rte_atomic64_t greads;
> 
> static volatile uint8_t writer_done;
> -static volatile uint8_t multi_writer_done[4];
> 
> uint16_t enabled_core_ids[RTE_MAX_LCORE];
> 
> @@ -690,7 +689,6 @@ struct {
> 	for (i = offset; i < offset + tbl_rwc_test_param.single_insert; i++)
> 		rte_hash_add_key(tbl_rwc_test_param.h,
> 				 tbl_rwc_test_param.keys_ks + i);
> -	multi_writer_done[pos_core] = 1;
> 	return 0;
> }
> 
> @@ -738,10 +736,9 @@ struct {
> 				rte_eal_remote_launch(test_rwc_reader,
> 						(void *)(uintptr_t)read_type,
> 							enabled_core_ids[i]);
> -			rte_eal_mp_wait_lcore();
> 
> 			for (i = 1; i <= rwc_core_cnt[n]; i++)
> -				if (lcore_config[i].ret < 0)
> +				if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)

(There are similar changes in other functions too.
I realize that this is a separate issue than what the patch is aimed for.
If you see fit, please integrate it, else I will put out a patch once your patch has been merged.)
> 					goto err;
> 
> 			unsigned long long cycles_per_lookup =
> @@ -758,6 +755,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> @@ -808,12 +806,11 @@ struct {
> 							enabled_core_ids[i]);
> 			ret = write_keys(write_type);
> 			writer_done = 1;
> -			rte_eal_mp_wait_lcore();
> 
> 			if (ret < 0)
> 				goto err;
> 			for (i = 1; i <= rwc_core_cnt[n]; i++)
> -				if (lcore_config[i].ret < 0)
> +				if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
> 					goto err;
> 
> 			unsigned long long cycles_per_lookup =
> @@ -830,6 +827,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> @@ -884,12 +882,11 @@ struct {
> 			write_type = WRITE_KEY_SHIFT;
> 			ret = write_keys(write_type);
> 			writer_done = 1;
> -			rte_eal_mp_wait_lcore();
> 
> 			if (ret < 0)
> 				goto err;
> 			for (i = 1; i <= rwc_core_cnt[n]; i++)
> -				if (lcore_config[i].ret < 0)
> +				if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
> 					goto err;
> 
> 			unsigned long long cycles_per_lookup =
> @@ -906,6 +903,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> @@ -960,12 +958,11 @@ struct {
> 			write_type = WRITE_KEY_SHIFT;
> 			ret = write_keys(write_type);
> 			writer_done = 1;
> -			rte_eal_mp_wait_lcore();
> 
> 			if (ret < 0)
> 				goto err;
> 			for (i = 1; i <= rwc_core_cnt[n]; i++)
> -				if (lcore_config[i].ret < 0)
> +				if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
> 					goto err;
> 
> 			unsigned long long cycles_per_lookup =
> @@ -982,6 +979,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> @@ -1035,12 +1033,11 @@ struct {
> 			write_type = WRITE_KEY_SHIFT;
> 			ret = write_keys(write_type);
> 			writer_done = 1;
> -			rte_eal_mp_wait_lcore();
> 
> 			if (ret < 0)
> 				goto err;
> 			for (i = 1; i <= rwc_core_cnt[n]; i++)
> -				if (lcore_config[i].ret < 0)
> +				if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
> 					goto err;
> 
> 			unsigned long long cycles_per_lookup =
> @@ -1056,6 +1053,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> @@ -1108,8 +1106,6 @@ struct {
> 
> 				rte_hash_reset(tbl_rwc_test_param.h);
> 				writer_done = 0;
> -				for (i = 0; i < 4; i++)
> -					multi_writer_done[i] = 0;
> 				write_type = WRITE_NO_KEY_SHIFT;
> 				if (write_keys(write_type) < 0)
> 					goto err;
> @@ -1133,15 +1129,15 @@ struct {
> 				}
> 
> 				/* Wait for writers to complete */
> -				for (i = 0; i < rwc_core_cnt[m]; i++)
> -					while
> -						(multi_writer_done[i] == 0);
> -				writer_done = 1;
> +				for (i = rwc_core_cnt[n] + 1;
> +				     i <= rwc_core_cnt[m] + rwc_core_cnt[n];
> +				     i++)
> +					rte_eal_wait_lcore(i);
rte_eal_wait_lcore(enabled_core_ids[i]);
> 
> -				rte_eal_mp_wait_lcore();
> +				writer_done = 1;
> 
> 				for (i = 1; i <= rwc_core_cnt[n]; i++)
> -					if (lcore_config[i].ret < 0)
> +					if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
> 						goto err;
> 
> 				unsigned long long cycles_per_lookup =
> @@ -1160,6 +1156,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> @@ -1222,10 +1219,9 @@ struct {
> 				}
> 			}
> 			writer_done = 1;
> -			rte_eal_mp_wait_lcore();
> 
> 			for (i = 1; i <= rwc_core_cnt[n]; i++)
> -				if (lcore_config[i].ret < 0)
> +				if (rte_eal_wait_lcore(i) < 0)
if (rte_eal_wait_lcore(enabled_core_ids[i]) < 0)
> 					goto err;
> 
> 			unsigned long long cycles_per_lookup =
> @@ -1242,6 +1238,7 @@ struct {
> 	return 0;
> 
> err:
> +	rte_eal_mp_wait_lcore();
> 	rte_hash_free(tbl_rwc_test_param.h);
> 	return -1;
> }
> -- 
> 1.8.3.1
> 
Thank you,
Dharmik Thakkar