DPDK patches and discussions
 help / color / mirror / Atom feed
From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
To: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>,
	"dev@dpdk.org" <dev@dpdk.org>,
	"david.marchand@redhat.com" <david.marchand@redhat.com>,
	"feifei.wang2@arm.com" <feifei.wang2@arm.com>
Cc: "ruifeng.wang@arm.com" <ruifeng.wang@arm.com>,
	"nd@arm.com" <nd@arm.com>,  Ola Liljedahl <ola.liljedahl@arm.com>,
	Feifei Wang <feifei.wang@arm.com>
Subject: Re: [dpdk-dev] [PATCH v2 6/6] test/ring: use relaxed barriers for ring stress test
Date: Thu, 7 Oct 2021 11:55:02 +0000	[thread overview]
Message-ID: <DM6PR11MB449169A0EFAE7B24076120E59AB19@DM6PR11MB4491.namprd11.prod.outlook.com> (raw)
In-Reply-To: <20210909231312.2572006-7-honnappa.nagarahalli@arm.com>



 
> wrk_cmd variable is used to signal the worker thread to start
> or stop the stress test loop. Relaxed barriers are used
> to achieve the same.
> 
> Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> Reviewed-by: Ola Liljedahl <ola.liljedahl@arm.com>
> Reviewed-by: Feifei Wang <feifei.wang@arm.com>
> ---
>  app/test/test_ring_stress_impl.h | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/app/test/test_ring_stress_impl.h b/app/test/test_ring_stress_impl.h
> index f9ca63b908..ee8293bb04 100644
> --- a/app/test/test_ring_stress_impl.h
> +++ b/app/test/test_ring_stress_impl.h
> @@ -22,7 +22,7 @@ enum {
>  	WRK_CMD_RUN,
>  };
> 
> -static volatile uint32_t wrk_cmd __rte_cache_aligned;
> +static volatile uint32_t wrk_cmd __rte_cache_aligned = WRK_CMD_STOP;

If we switch to using atomic load/store for 'wrk_cmd',
then we can get remove 'volatile' classifier in the 'wrk_cmd' definition above?  

> 
>  /* test run-time in seconds */
>  static const uint32_t run_time = 60;
> @@ -197,10 +197,12 @@ test_worker(void *arg, const char *fname, int32_t prcs)
>  	fill_ring_elm(&def_elm, UINT32_MAX);
>  	fill_ring_elm(&loc_elm, lc);
> 
> -	while (wrk_cmd != WRK_CMD_RUN) {
> -		rte_smp_rmb();
> +	/* Acquire ordering is not required as the main is not
> +	 * really releasing any data through 'wrk_cmd' to
> +	 * the worker.
> +	 */
> +	while (__atomic_load_n(&wrk_cmd, __ATOMIC_RELAXED) != WRK_CMD_RUN)
>  		rte_pause();
> -	}
> 
>  	cl = rte_rdtsc_precise();
> 
> @@ -242,7 +244,7 @@ test_worker(void *arg, const char *fname, int32_t prcs)
> 
>  		lcore_stat_update(&la->stats, 1, num, tm0 + tm1, prcs);
> 
> -	} while (wrk_cmd == WRK_CMD_RUN);
> +	} while (__atomic_load_n(&wrk_cmd, __ATOMIC_RELAXED) == WRK_CMD_RUN);
> 
>  	cl = rte_rdtsc_precise() - cl;
>  	if (prcs == 0)
> @@ -356,14 +358,12 @@ test_mt1(int (*test)(void *))
>  	}
> 
>  	/* signal worker to start test */
> -	wrk_cmd = WRK_CMD_RUN;
> -	rte_smp_wmb();
> +	__atomic_store_n(&wrk_cmd, WRK_CMD_RUN, __ATOMIC_RELEASE);
> 
>  	usleep(run_time * US_PER_S);
> 
>  	/* signal worker to start test */
> -	wrk_cmd = WRK_CMD_STOP;
> -	rte_smp_wmb();
> +	__atomic_store_n(&wrk_cmd, WRK_CMD_STOP, __ATOMIC_RELEASE);
> 
>  	/* wait for workers and collect stats. */
>  	mc = rte_lcore_id();
> --
> 2.25.1


  reply	other threads:[~2021-10-07 11:55 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-24 21:20 [dpdk-dev] [RFC 0/5] Use correct memory ordering in eal functions Honnappa Nagarahalli
2021-02-24 21:20 ` [dpdk-dev] [RFC 1/5] eal: reset lcore function pointer and argument Honnappa Nagarahalli
2021-02-24 21:20 ` [dpdk-dev] [RFC 2/5] eal: ensure memory operations are visible to worker Honnappa Nagarahalli
2021-02-24 21:20 ` [dpdk-dev] [RFC 3/5] eal: lcore state FINISHED is not required Honnappa Nagarahalli
     [not found]   ` <AM5PR0802MB2465B62994239817E0AC46C59E9E9@AM5PR0802MB2465.eurprd08.prod.outlook.com>
2021-02-25  8:44     ` [dpdk-dev] 回复: " Feifei Wang
2021-02-25 23:33       ` [dpdk-dev] " Honnappa Nagarahalli
2021-02-26  8:26         ` Thomas Monjalon
2021-03-02  3:13           ` Honnappa Nagarahalli
2021-03-19 13:42             ` Ananyev, Konstantin
2021-03-30  2:54               ` Honnappa Nagarahalli
2021-03-01  5:55         ` [dpdk-dev] 回复: " Feifei Wang
2021-02-24 21:20 ` [dpdk-dev] [RFC 4/5] eal: ensure memory operations are visible to main Honnappa Nagarahalli
2021-02-24 21:20 ` [dpdk-dev] [RFC 5/5] test/ring: use relaxed barriers for ring stress test Honnappa Nagarahalli
2021-03-01 16:41 ` [dpdk-dev] [RFC 0/5] Use correct memory ordering in eal functions Stephen Hemminger
2021-03-02 16:06   ` Honnappa Nagarahalli
2021-09-09 23:13 ` [dpdk-dev] [PATCH v2 0/6] " Honnappa Nagarahalli
2021-09-09 23:13   ` [dpdk-dev] [PATCH v2 1/6] eal: reset lcore function pointer and argument Honnappa Nagarahalli
2021-09-10  7:49     ` Bruce Richardson
2021-09-10  8:12       ` David Marchand
2021-09-11 22:19         ` Honnappa Nagarahalli
2021-09-09 23:13   ` [dpdk-dev] [PATCH v2 2/6] eal: ensure memory operations are visible to worker Honnappa Nagarahalli
2021-09-09 23:13   ` [dpdk-dev] [PATCH v2 3/6] eal: lcore state FINISHED is not required Honnappa Nagarahalli
2021-09-09 23:13   ` [dpdk-dev] [PATCH v2 4/6] eal: update rte_eal_wait_lcore definition Honnappa Nagarahalli
2021-09-09 23:37     ` Honnappa Nagarahalli
2021-09-09 23:13   ` [dpdk-dev] [PATCH v2 5/6] eal: ensure memory operations are visible to main Honnappa Nagarahalli
2021-09-09 23:13   ` [dpdk-dev] [PATCH v2 6/6] test/ring: use relaxed barriers for ring stress test Honnappa Nagarahalli
2021-10-07 11:55     ` Ananyev, Konstantin [this message]
2021-10-07 23:40       ` Honnappa Nagarahalli
2021-10-25  4:52 ` [dpdk-dev] [PATCH v3 0/4] Use correct memory ordering in eal functions Honnappa Nagarahalli
2021-10-25  4:52   ` [dpdk-dev] [PATCH v3 1/4] eal: reset lcore function pointer and argument Honnappa Nagarahalli
2021-10-25  4:52   ` [dpdk-dev] [PATCH v3 2/4] eal: lcore state FINISHED is not required Honnappa Nagarahalli
2021-10-25  4:52   ` [dpdk-dev] [PATCH v3 3/4] eal: use correct memory ordering Honnappa Nagarahalli
2021-10-25  4:52   ` [dpdk-dev] [PATCH v3 4/4] test/ring: use relaxed barriers for ring stress test Honnappa Nagarahalli
2021-10-25 16:23   ` [dpdk-dev] [PATCH v3 0/4] Use correct memory ordering in eal functions David Marchand

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=DM6PR11MB449169A0EFAE7B24076120E59AB19@DM6PR11MB4491.namprd11.prod.outlook.com \
    --to=konstantin.ananyev@intel.com \
    --cc=david.marchand@redhat.com \
    --cc=dev@dpdk.org \
    --cc=feifei.wang2@arm.com \
    --cc=feifei.wang@arm.com \
    --cc=honnappa.nagarahalli@arm.com \
    --cc=nd@arm.com \
    --cc=ola.liljedahl@arm.com \
    --cc=ruifeng.wang@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).