[v2] eal: fix check when retrieving current cpu affinity

  pthread_getaffinity_np returns a >0 value when failing.

This is mainly for the sake of correctness.
The only case where it could fail is when passing an incorrect cpuset
size wrt to the kernel.

Fixes: 2eba8d21f3c9 ("eal: restrict cores auto detection")
Cc: stable@dpdk.org
Signed-off-by: David Marchand <david.marchand@redhat.com>
---
Changelog since v1:
- added missing Cc: stable@dpdk.org

---
 lib/librte_eal/common/eal_common_options.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)
  

On 19-Feb-19 8:38 PM, David Marchand wrote:
> pthread_getaffinity_np returns a >0 value when failing.
> 
> This is mainly for the sake of correctness.
> The only case where it could fail is when passing an incorrect cpuset
> size wrt to the kernel.
> 
> Fixes: 2eba8d21f3c9 ("eal: restrict cores auto detection")
> Cc: stable@dpdk.org
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> ---

Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
  

Reviewed-by: Rami Rosen <ramirose@gmail.com>


בתאריך יום ג׳, 19 בפבר׳ 2019, 22:38, מאת David Marchand ‏<
david.marchand@redhat.com>:

> pthread_getaffinity_np returns a >0 value when failing.
>
> This is mainly for the sake of correctness.
> The only case where it could fail is when passing an incorrect cpuset
> size wrt to the kernel.
>
> Fixes: 2eba8d21f3c9 ("eal: restrict cores auto detection")
> Cc: stable@dpdk.org
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> ---
> Changelog since v1:
> - added missing Cc: stable@dpdk.org
>
> ---
>  lib/librte_eal/common/eal_common_options.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/lib/librte_eal/common/eal_common_options.c
> b/lib/librte_eal/common/eal_common_options.c
> index 6c96f45..1f45f82 100644
> --- a/lib/librte_eal/common/eal_common_options.c
> +++ b/lib/librte_eal/common/eal_common_options.c
> @@ -1343,10 +1343,9 @@ static int xdigit2val(unsigned char c)
>         unsigned int lcore_id;
>         unsigned int removed = 0;
>         rte_cpuset_t affinity_set;
> -       pthread_t tid = pthread_self();
>
> -       if (pthread_getaffinity_np(tid, sizeof(rte_cpuset_t),
> -                               &affinity_set) < 0)
> +       if (pthread_getaffinity_np(pthread_self(), sizeof(rte_cpuset_t),
> +                               &affinity_set))
>                 CPU_ZERO(&affinity_set);
>
>         for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
> --
> 1.8.3.1
>
>
  

20/02/2019 17:02, Burakov, Anatoly:
> On 19-Feb-19 8:38 PM, David Marchand wrote:
> > pthread_getaffinity_np returns a >0 value when failing.
> > 
> > This is mainly for the sake of correctness.
> > The only case where it could fail is when passing an incorrect cpuset
> > size wrt to the kernel.
> > 
> > Fixes: 2eba8d21f3c9 ("eal: restrict cores auto detection")
> > Cc: stable@dpdk.org
> > Signed-off-by: David Marchand <david.marchand@redhat.com>
> 
> Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>

Applied, thanks