X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=kernel%2Firq%2Faffinity.c;h=44a4eba80315cc098ecfa366ca1d88483641b12a;hb=f7b3ea8cf72f3d6060fe08e461805181e7450a13;hp=54083331f1bcb2523813161aa4aaf2ba250013b9;hpb=523f1ea76aad9025f9bd5258d77f4406fa9dbe5d;p=platform%2Fkernel%2Flinux-starfive.git diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index 5408333..44a4eba 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -7,403 +7,7 @@ #include #include #include -#include - -static void grp_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk, - unsigned int cpus_per_grp) -{ - const struct cpumask *siblmsk; - int cpu, sibl; - - for ( ; cpus_per_grp > 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_grp--; - - /* If the cpu has siblings, use them first */ - siblmsk = topology_sibling_cpumask(cpu); - for (sibl = -1; cpus_per_grp > 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_grp--; - } - } -} - -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; -} - -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); -} - -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)]); -} - -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; -} - -struct node_groups { - unsigned id; - - union { - unsigned ngroups; - unsigned ncpus; - }; -}; - -static int ncpus_cmp_func(const void *l, const void *r) -{ - const struct node_groups *ln = l; - const struct node_groups *rn = r; - - return ln->ncpus - rn->ncpus; -} - -/* - * Allocate group number for each node, so that for each node: - * - * 1) the allocated number is >= 1 - * - * 2) the allocated number is <= active CPU number of this node - * - * The actual allocated total groups may be less than @numgrps when - * active total CPU number is less than @numgrps. - * - * Active CPUs means the CPUs in '@cpu_mask AND @node_to_cpumask[]' - * for each node. - */ -static void alloc_nodes_groups(unsigned int numgrps, - cpumask_var_t *node_to_cpumask, - const struct cpumask *cpu_mask, - const nodemask_t nodemsk, - struct cpumask *nmsk, - struct node_groups *node_groups) -{ - unsigned n, remaining_ncpus = 0; - - for (n = 0; n < nr_node_ids; n++) { - node_groups[n].id = n; - node_groups[n].ncpus = UINT_MAX; - } - - for_each_node_mask(n, nodemsk) { - unsigned ncpus; - - cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]); - ncpus = cpumask_weight(nmsk); - - if (!ncpus) - continue; - remaining_ncpus += ncpus; - node_groups[n].ncpus = ncpus; - } - - numgrps = min_t(unsigned, remaining_ncpus, numgrps); - - sort(node_groups, nr_node_ids, sizeof(node_groups[0]), - ncpus_cmp_func, NULL); - - /* - * Allocate groups for each node according to the ratio of this - * node's nr_cpus to remaining un-assigned ncpus. 'numgrps' is - * bigger than number of active numa nodes. Always start the - * allocation from the node with minimized nr_cpus. - * - * This way guarantees that each active node gets allocated at - * least one group, and the theory is simple: over-allocation - * is only done when this node is assigned by one group, so - * other nodes will be allocated >= 1 groups, since 'numgrps' is - * bigger than number of numa nodes. - * - * One perfect invariant is that number of allocated groups for - * each node is <= CPU count of this node: - * - * 1) suppose there are two nodes: A and B - * ncpu(X) is CPU count of node X - * grps(X) is the group count allocated to node X via this - * algorithm - * - * ncpu(A) <= ncpu(B) - * ncpu(A) + ncpu(B) = N - * grps(A) + grps(B) = G - * - * grps(A) = max(1, round_down(G * ncpu(A) / N)) - * grps(B) = G - grps(A) - * - * both N and G are integer, and 2 <= G <= N, suppose - * G = N - delta, and 0 <= delta <= N - 2 - * - * 2) obviously grps(A) <= ncpu(A) because: - * - * if grps(A) is 1, then grps(A) <= ncpu(A) given - * ncpu(A) >= 1 - * - * otherwise, - * grps(A) <= G * ncpu(A) / N <= ncpu(A), given G <= N - * - * 3) prove how grps(B) <= ncpu(B): - * - * if round_down(G * ncpu(A) / N) == 0, vecs(B) won't be - * over-allocated, so grps(B) <= ncpu(B), - * - * otherwise: - * - * grps(A) = - * round_down(G * ncpu(A) / N) = - * round_down((N - delta) * ncpu(A) / N) = - * round_down((N * ncpu(A) - delta * ncpu(A)) / N) >= - * round_down((N * ncpu(A) - delta * N) / N) = - * cpu(A) - delta - * - * then: - * - * grps(A) - G >= ncpu(A) - delta - G - * => - * G - grps(A) <= G + delta - ncpu(A) - * => - * grps(B) <= N - ncpu(A) - * => - * grps(B) <= cpu(B) - * - * For nodes >= 3, it can be thought as one node and another big - * node given that is exactly what this algorithm is implemented, - * and we always re-calculate 'remaining_ncpus' & 'numgrps', and - * finally for each node X: grps(X) <= ncpu(X). - * - */ - for (n = 0; n < nr_node_ids; n++) { - unsigned ngroups, ncpus; - - if (node_groups[n].ncpus == UINT_MAX) - continue; - - WARN_ON_ONCE(numgrps == 0); - - ncpus = node_groups[n].ncpus; - ngroups = max_t(unsigned, 1, - numgrps * ncpus / remaining_ncpus); - WARN_ON_ONCE(ngroups > ncpus); - - node_groups[n].ngroups = ngroups; - - remaining_ncpus -= ncpus; - numgrps -= ngroups; - } -} - -static int __group_cpus_evenly(unsigned int startgrp, unsigned int numgrps, - cpumask_var_t *node_to_cpumask, - const struct cpumask *cpu_mask, - struct cpumask *nmsk, struct cpumask *masks) -{ - unsigned int i, n, nodes, cpus_per_grp, extra_grps, done = 0; - unsigned int last_grp = numgrps; - unsigned int curgrp = startgrp; - nodemask_t nodemsk = NODE_MASK_NONE; - struct node_groups *node_groups; - - if (cpumask_empty(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 groups we just spread the groups across the nodes. - */ - if (numgrps <= nodes) { - 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[curgrp], &masks[curgrp], nmsk); - if (++curgrp == last_grp) - curgrp = 0; - } - return numgrps; - } - - node_groups = kcalloc(nr_node_ids, - sizeof(struct node_groups), - GFP_KERNEL); - if (!node_groups) - return -ENOMEM; - - /* allocate group number for each node */ - alloc_nodes_groups(numgrps, node_to_cpumask, cpu_mask, - nodemsk, nmsk, node_groups); - for (i = 0; i < nr_node_ids; i++) { - unsigned int ncpus, v; - struct node_groups *nv = &node_groups[i]; - - if (nv->ngroups == UINT_MAX) - continue; - - /* Get the cpus on this node which are in the mask */ - cpumask_and(nmsk, cpu_mask, node_to_cpumask[nv->id]); - ncpus = cpumask_weight(nmsk); - if (!ncpus) - continue; - - WARN_ON_ONCE(nv->ngroups > ncpus); - - /* Account for rounding errors */ - extra_grps = ncpus - nv->ngroups * (ncpus / nv->ngroups); - - /* Spread allocated groups on CPUs of the current node */ - for (v = 0; v < nv->ngroups; v++, curgrp++) { - cpus_per_grp = ncpus / nv->ngroups; - - /* Account for extra groups to compensate rounding errors */ - if (extra_grps) { - cpus_per_grp++; - --extra_grps; - } - - /* - * wrapping has to be considered given 'startgrp' - * may start anywhere - */ - if (curgrp >= last_grp) - curgrp = 0; - grp_spread_init_one(&masks[curgrp], nmsk, - cpus_per_grp); - } - done += nv->ngroups; - } - kfree(node_groups); - return done; -} - -/* - * build affinity in two stages for each group, and try to put close CPUs - * in viewpoint of CPU and NUMA locality into same group, and we run - * two-stage grouping: - * - * 1) allocate present CPUs on these groups evenly first - * 2) allocate other possible CPUs on these groups evenly - */ -static struct cpumask *group_cpus_evenly(unsigned int numgrps) -{ - unsigned int curgrp = 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 NULL; - - if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL)) - goto fail_nmsk; - - node_to_cpumask = alloc_node_to_cpumask(); - if (!node_to_cpumask) - goto fail_npresmsk; - - masks = kcalloc(numgrps, sizeof(*masks), GFP_KERNEL); - if (!masks) - goto fail_node_to_cpumask; - - /* Stabilize the cpumasks */ - cpus_read_lock(); - build_node_to_cpumask(node_to_cpumask); - - /* grouping present CPUs first */ - ret = __group_cpus_evenly(curgrp, numgrps, node_to_cpumask, - cpu_present_mask, nmsk, masks); - if (ret < 0) - goto fail_build_affinity; - nr_present = ret; - - /* - * Allocate non present CPUs starting from the next group to be - * handled. If the grouping of present CPUs already exhausted the - * group space, assign the non present CPUs to the already - * allocated out groups. - */ - if (nr_present >= numgrps) - curgrp = 0; - else - curgrp = nr_present; - cpumask_andnot(npresmsk, cpu_possible_mask, cpu_present_mask); - ret = __group_cpus_evenly(curgrp, numgrps, node_to_cpumask, - npresmsk, nmsk, masks); - if (ret >= 0) - nr_others = ret; - - fail_build_affinity: - cpus_read_unlock(); - - if (ret >= 0) - WARN_ON(nr_present + nr_others < numgrps); - - fail_node_to_cpumask: - free_node_to_cpumask(node_to_cpumask); - - fail_npresmsk: - free_cpumask_var(npresmsk); - - fail_nmsk: - free_cpumask_var(nmsk); - if (ret < 0) { - kfree(masks); - return NULL; - } - return masks; -} +#include static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs) {