Release 4.17 kernel/irq/affinity.c
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2016 Thomas Gleixner.
* Copyright (C) 2016-2017 Christoph Hellwig.
*/
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/cpu.h>
static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk,
int cpus_per_vec)
{
const struct cpumask *siblmsk;
int cpu, sibl;
for ( ; cpus_per_vec > 0; ) {
cpu = cpumask_first(nmsk);
/* Should not happen, but I'm too lazy to think about it */
if (cpu >= nr_cpu_ids)
return;
cpumask_clear_cpu(cpu, nmsk);
cpumask_set_cpu(cpu, irqmsk);
cpus_per_vec--;
/* If the cpu has siblings, use them first */
siblmsk = topology_sibling_cpumask(cpu);
for (sibl = -1; cpus_per_vec > 0; ) {
sibl = cpumask_next(sibl, siblmsk);
if (sibl >= nr_cpu_ids)
break;
if (!cpumask_test_and_clear_cpu(sibl, nmsk))
continue;
cpumask_set_cpu(sibl, irqmsk);
cpus_per_vec--;
}
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Thomas Gleixner | 131 | 100.00% | 1 | 100.00% |
| Total | 131 | 100.00% | 1 | 100.00% |
static cpumask_var_t *alloc_node_to_cpumask(void)
{
cpumask_var_t *masks;
int node;
masks = kcalloc(nr_node_ids, sizeof(cpumask_var_t), GFP_KERNEL);
if (!masks)
return NULL;
for (node = 0; node < nr_node_ids; node++) {
if (!zalloc_cpumask_var(&masks[node], GFP_KERNEL))
goto out_unwind;
}
return masks;
out_unwind:
while (--node >= 0)
free_cpumask_var(masks[node]);
kfree(masks);
return NULL;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Christoph Hellwig | 97 | 98.98% | 1 | 50.00% |
| Ming Lei | 1 | 1.02% | 1 | 50.00% |
| Total | 98 | 100.00% | 2 | 100.00% |
static void free_node_to_cpumask(cpumask_var_t *masks)
{
int node;
for (node = 0; node < nr_node_ids; node++)
free_cpumask_var(masks[node]);
kfree(masks);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Christoph Hellwig | 38 | 97.44% | 1 | 50.00% |
| Ming Lei | 1 | 2.56% | 1 | 50.00% |
| Total | 39 | 100.00% | 2 | 100.00% |
static void build_node_to_cpumask(cpumask_var_t *masks)
{
int cpu;
for_each_possible_cpu(cpu)
cpumask_set_cpu(cpu, masks[cpu_to_node(cpu)]);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Christoph Hellwig | 29 | 96.67% | 2 | 66.67% |
| Ming Lei | 1 | 3.33% | 1 | 33.33% |
| Total | 30 | 100.00% | 3 | 100.00% |
static int get_nodes_in_cpumask(cpumask_var_t *node_to_cpumask,
const struct cpumask *mask, nodemask_t *nodemsk)
{
int n, nodes = 0;
/* Calculate the number of nodes in the supplied affinity mask */
for_each_node(n) {
if (cpumask_intersects(mask, node_to_cpumask[n])) {
node_set(n, *nodemsk);
nodes++;
}
}
return nodes;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Thomas Gleixner | 49 | 79.03% | 1 | 25.00% |
| Christoph Hellwig | 6 | 9.68% | 1 | 25.00% |
| Guilherme G. Piccoli | 5 | 8.06% | 1 | 25.00% |
| Ming Lei | 2 | 3.23% | 1 | 25.00% |
| Total | 62 | 100.00% | 4 | 100.00% |
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 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;
if (!cpumask_weight(cpu_mask))
return 0;
nodes = get_nodes_in_cpumask(node_to_cpumask, cpu_mask, &nodemsk);
/*
* 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 (numvecs <= nodes) {
for_each_node_mask(n, nodemsk) {
cpumask_copy(masks + curvec, node_to_cpumask[n]);
if (++done == numvecs)
break;
if (++curvec == last_affv)
curvec = affd->pre_vectors;
}
goto out;
}
for_each_node_mask(n, nodemsk) {
int ncpus, v, vecs_to_assign, vecs_per_node;
/* Spread the vectors per node */
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]);
/* Calculate the number of cpus per vector */
ncpus = cpumask_weight(nmsk);
vecs_to_assign = min(vecs_per_node, ncpus);
/* Account for rounding errors */
extra_vecs = ncpus - vecs_to_assign * (ncpus / vecs_to_assign);
for (v = 0; curvec < last_affv && v < vecs_to_assign;
curvec++, v++) {
cpus_per_vec = ncpus / vecs_to_assign;
/* Account for extra vectors to compensate rounding errors */
if (extra_vecs) {
cpus_per_vec++;
--extra_vecs;
}
irq_spread_init_one(masks + curvec, nmsk, cpus_per_vec);
}
done += v;
if (done >= numvecs)
break;
if (curvec >= last_affv)
curvec = affd->pre_vectors;
--nodes;
}
out:
return done;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Thomas Gleixner | 145 | 47.39% | 1 | 8.33% |
| Ming Lei | 101 | 33.01% | 4 | 33.33% |
| Keith Busch | 42 | 13.73% | 3 | 25.00% |
| Christoph Hellwig | 17 | 5.56% | 3 | 25.00% |
| Guilherme G. Piccoli | 1 | 0.33% | 1 | 8.33% |
| Total | 306 | 100.00% | 12 | 100.00% |
/**
* irq_create_affinity_masks - Create affinity masks for multiqueue spreading
* @nvecs: The total number of vectors
* @affd: Description of the affinity requirements
*
* Returns the masks pointer or NULL if allocation failed.
*/
struct cpumask *
irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd)
{
int affvecs = nvecs - affd->pre_vectors - affd->post_vectors;
int curvec, usedvecs;
cpumask_var_t nmsk, npresmsk, *node_to_cpumask;
struct cpumask *masks = NULL;
/*
* If there aren't any vectors left after applying the pre/post
* vectors don't bother with assigning affinity.
*/
if (nvecs == affd->pre_vectors + affd->post_vectors)
return NULL;
if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))
return NULL;
if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL))
goto outcpumsk;
node_to_cpumask = alloc_node_to_cpumask();
if (!node_to_cpumask)
goto outnpresmsk;
masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL);
if (!masks)
goto outnodemsk;
/* Fill out vectors at the beginning that don't need affinity */
for (curvec = 0; curvec < affd->pre_vectors; curvec++)
cpumask_copy(masks + curvec, irq_default_affinity);
/* Stabilize the cpumasks */
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 non present CPUs starting from the next vector to be
* handled. If the spreading of present CPUs already exhausted the
* vector space, assign the non present CPUs to the already spread
* out vectors.
*/
if (usedvecs >= affvecs)
curvec = affd->pre_vectors;
else
curvec = affd->pre_vectors + usedvecs;
cpumask_andnot(npresmsk, cpu_possible_mask, cpu_present_mask);
usedvecs += irq_build_affinity_masks(affd, curvec, affvecs,
node_to_cpumask, npresmsk,
nmsk, masks);
put_online_cpus();
/* Fill out vectors at the end that don't need affinity */
if (usedvecs >= affvecs)
curvec = affd->pre_vectors + affvecs;
else
curvec = affd->pre_vectors + usedvecs;
for (; curvec < nvecs; curvec++)
cpumask_copy(masks + curvec, irq_default_affinity);
outnodemsk:
free_node_to_cpumask(node_to_cpumask);
outnpresmsk:
free_cpumask_var(npresmsk);
outcpumsk:
free_cpumask_var(nmsk);
return masks;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Ming Lei | 264 | 87.13% | 4 | 44.44% |
| Christoph Hellwig | 22 | 7.26% | 2 | 22.22% |
| Thomas Gleixner | 17 | 5.61% | 3 | 33.33% |
| Total | 303 | 100.00% | 9 | 100.00% |
/**
* irq_calc_affinity_vectors - Calculate the optimal number of vectors
* @minvec: The minimum number of vectors available
* @maxvec: The maximum number of vectors available
* @affd: Description of the affinity requirements
*/
int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity *affd)
{
int resv = affd->pre_vectors + affd->post_vectors;
int vecs = maxvec - resv;
int ret;
if (resv > minvec)
return 0;
get_online_cpus();
ret = min_t(int, cpumask_weight(cpu_possible_mask), vecs) + resv;
put_online_cpus();
return ret;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Christoph Hellwig | 41 | 56.94% | 3 | 60.00% |
| Thomas Gleixner | 19 | 26.39% | 1 | 20.00% |
| Michael Hernandez | 12 | 16.67% | 1 | 20.00% |
| Total | 72 | 100.00% | 5 | 100.00% |
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Ming Lei | 371 | 35.10% | 4 | 21.05% |
| Thomas Gleixner | 361 | 34.15% | 3 | 15.79% |
| Christoph Hellwig | 263 | 24.88% | 6 | 31.58% |
| Keith Busch | 42 | 3.97% | 3 | 15.79% |
| Michael Hernandez | 13 | 1.23% | 1 | 5.26% |
| Guilherme G. Piccoli | 6 | 0.57% | 1 | 5.26% |
| Greg Kroah-Hartman | 1 | 0.09% | 1 | 5.26% |
| Total | 1057 | 100.00% | 19 | 100.00% |
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.