2021-06-29 18:56 (UTC-0700), Narcisa Ana Maria Vasile:
> From: Narcisa Vasile <navas...@microsoft.com>
>
> rte_cpuset_t describes a set of CPUs by using an array of masks
> named '_bits'. Each element in the '_bits' array represents
> a bit mask, with each bit corresponding to a CPU.
> The maximum number of CPUs is given by 'CPU_SETSIZE'.
> The number of bit masks is computed using '_NUM_SETS(CPU_SETSIZE)'.
>
> count_cpu() should count the number of CPUs enabled in the set 's'.
> Currently, it iterates through the number of masks in the
> set 's', instead of iterating through all the bits in all the masks.
> For example, if '_NUM_SETS(CPU_SETSIZE)' returns 2,
> which means there are 2 bit masks: _bits[0] and _bits[1],
> count_cpu() would only check if CPUs '0' and '1' are enabled.
> The correct behavior is to iterate through all the CPUs in the set and
> count the ones that are enabled.
>
> This patch fixes count_cpu() to ensure all the bits in all the masks
> are checked to compute the correct number of CPUs enabled in 's'.
>
> Fixes: e8428a9d89f1 ("eal/windows: add some basic functions and macros")
> Cc: pallavi.ka...@intel.com
> Cc: sta...@dpdk.org
>
> Signed-off-by: Narcisa Vasile <navas...@microsoft.com>
> ---
> v2:
> * Fix commit message.
>
> lib/eal/windows/include/sched.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/eal/windows/include/sched.h b/lib/eal/windows/include/sched.h
> index ff572b5dcb..bc31cc8465 100644
> --- a/lib/eal/windows/include/sched.h
> +++ b/lib/eal/windows/include/sched.h
> @@ -49,7 +49,7 @@ count_cpu(rte_cpuset_t *s)
> unsigned int _i;
> int count = 0;
>
> - for (_i = 0; _i < _NUM_SETS(CPU_SETSIZE); _i++)
> + for (_i = 0; _i < CPU_SETSIZE; _i++)
> if (CPU_ISSET(_i, s) != 0LL)
> count++;
> return count;
Sorry, I lost track of this patch.
Great and thorough explanation, but I don't think it needs to be so long.
Suggestion:
On Windows, -l/--lcores EAL option was unable to process CPU sets
containing CPUs other than 0 and 1, because CPU_COUNT() macro
only checked these CPUs in the set. Fix CPU_COUNT() by enumerating
all possible CPU indices.
Whatever message is taken in the end,
Acked-by: Dmitry Kozlyuk <dmitry.kozl...@gmail.com>
