"Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> writes:
> The most common case for certain node_random usage (demotion nodemask) is with
> nodemask weight 1. We can avoid calling get_random_init() in that case and
> always return the only node set in the nodemask.
I think that this patch can sit between [5/9] and [6/9], just after it
is used.
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
> ---
> lib/nodemask.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/lib/nodemask.c b/lib/nodemask.c
> index e22647f5181b..c91a6b0404a5 100644
> --- a/lib/nodemask.c
> +++ b/lib/nodemask.c
> @@ -20,12 +20,21 @@ EXPORT_SYMBOL(__next_node_in);
> */
> int node_random(const nodemask_t *maskp)
> {
> - int w, bit = NUMA_NO_NODE;
> + int w, bit;
>
> w = nodes_weight(*maskp);
> - if (w)
> + switch (w) {
> + case 0:
> + bit = NUMA_NO_NODE;
> + break;
> + case 1:
> + bit = __first_node(maskp);
Per my understanding, first_node() is the formal API and we should use
that? Just like we use nodes_weight() instead of __nodes_weight().
Best Regards,
Huang, Ying
> + break;
> + default:
> bit = bitmap_ord_to_pos(maskp->bits,
> - get_random_int() % w, MAX_NUMNODES);
> + get_random_int() % w, MAX_NUMNODES);
> + break;
> + }
> return bit;
> }
> #endif
