On Mon, Oct 29, 2018 at 10:37:35AM -0600, Jens Axboe wrote:
> A driver may have a need to allocate multiple sets of MSI/MSI-X
> interrupts, and have them appropriately affinitized. Add support for
> defining a number of sets in the irq_affinity structure, of varying
> sizes, and get each set affinitized correctly across the machine.
>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> ---
> include/linux/interrupt.h | 4 ++++
> kernel/irq/affinity.c | 40 ++++++++++++++++++++++++++++++---------
> 2 files changed, 35 insertions(+), 9 deletions(-)
>
> diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
> index 1d6711c28271..ca397ff40836 100644
> --- a/include/linux/interrupt.h
> +++ b/include/linux/interrupt.h
> @@ -247,10 +247,14 @@ struct irq_affinity_notify {
> * the MSI(-X) vector space
> * @post_vectors: Don't apply affinity to @post_vectors at end of
> * the MSI(-X) vector space
> + * @nr_sets: Length of passed in *sets array
> + * @sets: Number of affinitized sets
> */
> struct irq_affinity {
> int pre_vectors;
> int post_vectors;
> + int nr_sets;
> + int *sets;
> };
>
> #if defined(CONFIG_SMP)
> diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
> index f4f29b9d90ee..2046a0f0f0f1 100644
> --- a/kernel/irq/affinity.c
> +++ b/kernel/irq/affinity.c
> @@ -180,6 +180,7 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd)
> int curvec, usedvecs;
> cpumask_var_t nmsk, npresmsk, *node_to_cpumask;
> struct cpumask *masks = NULL;
> + int i, nr_sets;
>
> /*
> * If there aren't any vectors left after applying the pre/post
> @@ -210,10 +211,23 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd)
> get_online_cpus();
> build_node_to_cpumask(node_to_cpumask);
>
> - /* Spread on present CPUs starting from affd->pre_vectors */
> - usedvecs = irq_build_affinity_masks(affd, curvec, affvecs,
> - node_to_cpumask, cpu_present_mask,
> - nmsk, masks);
> + /*
> + * Spread on present CPUs starting from affd->pre_vectors. If we
> + * have multiple sets, build each sets affinity mask separately.
> + */
> + nr_sets = affd->nr_sets;
> + if (!nr_sets)
> + nr_sets = 1;
> +
> + for (i = 0, usedvecs = 0; i < nr_sets; i++) {
> + int this_vecs = affd->sets ? affd->sets[i] : affvecs;
> + int nr;
> +
> + nr = irq_build_affinity_masks(affd, curvec, this_vecs,
> + node_to_cpumask, cpu_present_mask,
> + nmsk, masks + usedvecs);
> + usedvecs += nr;
> + }
>
> /*
> * Spread on non present CPUs starting from the next vector to be
> @@ -258,13 +272,21 @@ int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity
> {
> int resv = affd->pre_vectors + affd->post_vectors;
> int vecs = maxvec - resv;
> - int ret;
> + int set_vecs;
>
> if (resv > minvec)
> return 0;
>
> - get_online_cpus();
> - ret = min_t(int, cpumask_weight(cpu_possible_mask), vecs) + resv;
> - put_online_cpus();
> - return ret;
> + if (affd->nr_sets) {
> + int i;
> +
> + for (i = 0, set_vecs = 0; i < affd->nr_sets; i++)
> + set_vecs += affd->sets[i];
> + } else {
> + get_online_cpus();
> + set_vecs = cpumask_weight(cpu_possible_mask);
> + put_online_cpus();
> + }
> +
> + return resv + min(set_vecs, vecs);
> }
> --
> 2.17.1
>
Looks fine:
Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
--
Ming
