[ovs-dev] [PATCH 3/3] dpdk: Use ovs-numa provided functions to manage thread affinity.

[William Tu]

On Tue, Aug 13, 2019 at 8:30 AM Ilya Maximets <i.maximets at samsung.com> wrote:
>
> This allows to decrease code duplication and avoid using Linux-specific
> functions (this might be useful in the future if we'll try to allow
> running OvS+DPDK on FreeBSD).
>
> Signed-off-by: Ilya Maximets <i.maximets at samsung.com>

LGTM
Acked-by: William Tu <u9012063 at gmail.com>


> ---
>  lib/dpdk.c | 27 ++++++++++++---------------
>  1 file changed, 12 insertions(+), 15 deletions(-)
>
> diff --git a/lib/dpdk.c b/lib/dpdk.c
> index fc58de55a..6f297d918 100644
> --- a/lib/dpdk.c
> +++ b/lib/dpdk.c
> @@ -275,7 +275,7 @@ dpdk_init__(const struct smap *ovs_other_config)
>      int result;
>      bool auto_determine = true;
>      int err = 0;
> -    cpu_set_t cpuset;
> +    struct ovs_numa_dump *affinity = NULL;
>      struct svec args = SVEC_EMPTY_INITIALIZER;
>
>      log_stream = fopencookie(NULL, "w+", dpdk_log_func);
> @@ -357,22 +357,22 @@ dpdk_init__(const struct smap *ovs_other_config)
>       * lcore for the DPDK Master.
>       */
>      if (auto_determine) {
> +        const struct ovs_numa_info_core *core;
>          int cpu = 0;
>
>          /* Get the main thread affinity */
> -        CPU_ZERO(&cpuset);
> -        err = pthread_getaffinity_np(pthread_self(), sizeof(cpu_set_t),
> -                                     &cpuset);
> -        if (!err) {
> -            for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
> -                if (CPU_ISSET(cpu, &cpuset)) {
> -                    break;
> +        affinity = ovs_numa_thread_getaffinity_dump();
> +        if (affinity) {
> +            cpu = INT_MAX;
> +            FOR_EACH_CORE_ON_DUMP (core, affinity) {
> +                if (cpu > core->core_id) {
> +                    cpu = core->core_id;
>                  }
>              }
>          } else {
>              /* User did not set dpdk-lcore-mask and unable to get current
>               * thread affintity - default to core #0 */
> -            VLOG_ERR("Thread getaffinity error %d. Using core #0", err);
> +            VLOG_ERR("Thread getaffinity failed. Using core #0");
>          }
>          svec_add(&args, "-l");
>          svec_add_nocopy(&args, xasprintf("%d", cpu));
> @@ -403,12 +403,9 @@ dpdk_init__(const struct smap *ovs_other_config)
>      svec_destroy(&args);
>
>      /* Set the main thread affinity back to pre rte_eal_init() value */
> -    if (auto_determine && !err) {
> -        err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t),
> -                                     &cpuset);
> -        if (err) {
> -            VLOG_ERR("Thread setaffinity error %d", err);
> -        }
> +    if (affinity) {
> +        ovs_numa_thread_setaffinity_dump(affinity);
> +        ovs_numa_dump_destroy(affinity);
>      }
>
>      if (result < 0) {
> --
> 2.17.1
>