6.1-stable review patch. If anyone has any objections, please let me know.
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From: Ming Lei ming.lei@redhat.com
[ Upstream commit e7bdd7f0cbd1c001bb9b4d3313edc5ee094bc3f8 ]
Prepare for abstracting irq_build_affinity_masks() into a public function for assigning all CPUs evenly into several groups.
Don't pass irq_affinity_desc array to irq_build_affinity_masks, instead return a cpumask array by storing each assigned group into one element of the array.
This allows to provide a generic interface for grouping all CPUs evenly from a NUMA and CPU locality viewpoint, and the cost is one extra allocation in irq_build_affinity_masks(), which should be fine since it is done via GFP_KERNEL and irq_build_affinity_masks() is a slow path anyway.
Signed-off-by: Ming Lei ming.lei@redhat.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: John Garry john.g.garry@oracle.com Reviewed-by: Jens Axboe axboe@kernel.dk Link: https://lore.kernel.org/r/20221227022905.352674-4-ming.lei@redhat.com Stable-dep-of: 0263f92fadbb ("lib/group_cpus.c: avoid acquiring cpu hotplug lock in group_cpus_evenly") Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/irq/affinity.c | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-)
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index da6379cd27fd4..00bba1020ecb2 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -249,7 +249,7 @@ static int __irq_build_affinity_masks(unsigned int startvec, cpumask_var_t *node_to_cpumask, const struct cpumask *cpu_mask, struct cpumask *nmsk, - struct irq_affinity_desc *masks) + struct cpumask *masks) { unsigned int i, n, nodes, cpus_per_vec, extra_vecs, done = 0; unsigned int last_affv = numvecs; @@ -270,7 +270,7 @@ static int __irq_build_affinity_masks(unsigned int startvec, for_each_node_mask(n, nodemsk) { /* Ensure that only CPUs which are in both masks are set */ cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]); - cpumask_or(&masks[curvec].mask, &masks[curvec].mask, nmsk); + cpumask_or(&masks[curvec], &masks[curvec], nmsk); if (++curvec == last_affv) curvec = 0; } @@ -321,7 +321,7 @@ static int __irq_build_affinity_masks(unsigned int startvec, */ if (curvec >= last_affv) curvec = 0; - irq_spread_init_one(&masks[curvec].mask, nmsk, + irq_spread_init_one(&masks[curvec], nmsk, cpus_per_vec); } done += nv->nvectors; @@ -335,16 +335,16 @@ static int __irq_build_affinity_masks(unsigned int startvec, * 1) spread present CPU on these vectors * 2) spread other possible CPUs on these vectors */ -static int irq_build_affinity_masks(unsigned int numvecs, - struct irq_affinity_desc *masks) +static struct cpumask *irq_build_affinity_masks(unsigned int numvecs) { unsigned int curvec = 0, nr_present = 0, nr_others = 0; cpumask_var_t *node_to_cpumask; cpumask_var_t nmsk, npresmsk; int ret = -ENOMEM; + struct cpumask *masks = NULL;
if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL)) - return ret; + return NULL;
if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL)) goto fail_nmsk; @@ -353,6 +353,10 @@ static int irq_build_affinity_masks(unsigned int numvecs, if (!node_to_cpumask) goto fail_npresmsk;
+ masks = kcalloc(numvecs, sizeof(*masks), GFP_KERNEL); + if (!masks) + goto fail_node_to_cpumask; + /* Stabilize the cpumasks */ cpus_read_lock(); build_node_to_cpumask(node_to_cpumask); @@ -386,6 +390,7 @@ static int irq_build_affinity_masks(unsigned int numvecs, if (ret >= 0) WARN_ON(nr_present + nr_others < numvecs);
+ fail_node_to_cpumask: free_node_to_cpumask(node_to_cpumask);
fail_npresmsk: @@ -393,7 +398,11 @@ static int irq_build_affinity_masks(unsigned int numvecs,
fail_nmsk: free_cpumask_var(nmsk); - return ret < 0 ? ret : 0; + if (ret < 0) { + kfree(masks); + return NULL; + } + return masks; }
static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs) @@ -457,13 +466,18 @@ irq_create_affinity_masks(unsigned int nvecs, struct irq_affinity *affd) */ for (i = 0, usedvecs = 0; i < affd->nr_sets; i++) { unsigned int this_vecs = affd->set_size[i]; - int ret; + int j; + struct cpumask *result = irq_build_affinity_masks(this_vecs);
- ret = irq_build_affinity_masks(this_vecs, &masks[curvec]); - if (ret) { + if (!result) { kfree(masks); return NULL; } + + for (j = 0; j < this_vecs; j++) + cpumask_copy(&masks[curvec + j].mask, &result[j]); + kfree(result); + curvec += this_vecs; usedvecs += this_vecs; }