From 1a2d0914e23aab386f5d5acb689777e24151c2c8 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 8 Mar 2018 18:53:57 +0800 Subject: [PATCH] genirq/affinity: Allow irq spreading from a given starting point To support two stage irq vector spreading, it's required to add a starting point to the spreading function. No functional change, just preparatory work for the actual two stage change. [ tglx: Renamed variables, tidied up the code and massaged changelog ] Signed-off-by: Ming Lei Signed-off-by: Thomas Gleixner Reviewed-by: Christoph Hellwig Cc: Jens Axboe Cc: linux-block@vger.kernel.org Cc: Laurence Oberman Cc: Christoph Hellwig Link: https://lkml.kernel.org/r/20180308105358.1506-4-ming.lei@redhat.com --- kernel/irq/affinity.c | 35 ++++++++++++++++++++--------------- 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index a9c36904500c..213695a27ddb 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -94,17 +94,17 @@ static int get_nodes_in_cpumask(cpumask_var_t *node_to_cpumask, return nodes; } -static int irq_build_affinity_masks(int nvecs, const struct irq_affinity *affd, +static int irq_build_affinity_masks(const struct irq_affinity *affd, + int startvec, int numvecs, cpumask_var_t *node_to_cpumask, const struct cpumask *cpu_mask, struct cpumask *nmsk, struct cpumask *masks) { - int affv = nvecs - affd->pre_vectors - affd->post_vectors; - int last_affv = affv + affd->pre_vectors; - int curvec = affd->pre_vectors; + int n, nodes, cpus_per_vec, extra_vecs, done = 0; + int last_affv = affd->pre_vectors + numvecs; + int curvec = startvec; nodemask_t nodemsk = NODE_MASK_NONE; - int n, nodes, cpus_per_vec, extra_vecs; nodes = get_nodes_in_cpumask(node_to_cpumask, cpu_mask, &nodemsk); @@ -112,12 +112,13 @@ static int irq_build_affinity_masks(int nvecs, const struct irq_affinity *affd, * If the number of nodes in the mask is greater than or equal the * number of vectors we just spread the vectors across the nodes. */ - if (affv <= nodes) { + if (numvecs <= nodes) { for_each_node_mask(n, nodemsk) { - cpumask_copy(masks + curvec, - node_to_cpumask[n]); - if (++curvec == last_affv) + cpumask_copy(masks + curvec, node_to_cpumask[n]); + if (++done == numvecs) break; + if (++curvec == last_affv) + curvec = affd->pre_vectors; } goto out; } @@ -126,7 +127,7 @@ static int irq_build_affinity_masks(int nvecs, const struct irq_affinity *affd, int ncpus, v, vecs_to_assign, vecs_per_node; /* Spread the vectors per node */ - vecs_per_node = (affv - (curvec - affd->pre_vectors)) / nodes; + vecs_per_node = (numvecs - (curvec - affd->pre_vectors)) / nodes; /* Get the cpus on this node which are in the mask */ cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]); @@ -150,13 +151,16 @@ static int irq_build_affinity_masks(int nvecs, const struct irq_affinity *affd, irq_spread_init_one(masks + curvec, nmsk, cpus_per_vec); } - if (curvec >= last_affv) + done += v; + if (done >= numvecs) break; + if (curvec >= last_affv) + curvec = affd->pre_vectors; --nodes; } out: - return curvec - affd->pre_vectors; + return done; } /** @@ -169,9 +173,9 @@ out: struct cpumask * irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) { + int curvec, affvecs = nvecs - affd->pre_vectors - affd->post_vectors; cpumask_var_t nmsk, *node_to_cpumask; struct cpumask *masks = NULL; - int curvec; /* * If there aren't any vectors left after applying the pre/post @@ -198,8 +202,9 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) /* Stabilize the cpumasks */ get_online_cpus(); build_node_to_cpumask(node_to_cpumask); - curvec += irq_build_affinity_masks(nvecs, affd, node_to_cpumask, - cpu_possible_mask, nmsk, masks); + curvec += irq_build_affinity_masks(affd, curvec, affvecs, + node_to_cpumask, cpu_possible_mask, + nmsk, masks); put_online_cpus(); /* Fill out vectors at the end that don't need affinity */ -- 2.20.1