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-rw-r--r--kernel/sched.c290
1 files changed, 236 insertions, 54 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 5f889d0cbfcc..50860ad5b624 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4779,7 +4779,7 @@ static int sd_parent_degenerate(struct sched_domain *sd,
4779 * Attach the domain 'sd' to 'cpu' as its base domain. Callers must 4779 * Attach the domain 'sd' to 'cpu' as its base domain. Callers must
4780 * hold the hotplug lock. 4780 * hold the hotplug lock.
4781 */ 4781 */
4782void cpu_attach_domain(struct sched_domain *sd, int cpu) 4782static void cpu_attach_domain(struct sched_domain *sd, int cpu)
4783{ 4783{
4784 runqueue_t *rq = cpu_rq(cpu); 4784 runqueue_t *rq = cpu_rq(cpu);
4785 struct sched_domain *tmp; 4785 struct sched_domain *tmp;
@@ -4802,7 +4802,7 @@ void cpu_attach_domain(struct sched_domain *sd, int cpu)
4802} 4802}
4803 4803
4804/* cpus with isolated domains */ 4804/* cpus with isolated domains */
4805cpumask_t __devinitdata cpu_isolated_map = CPU_MASK_NONE; 4805static cpumask_t __devinitdata cpu_isolated_map = CPU_MASK_NONE;
4806 4806
4807/* Setup the mask of cpus configured for isolated domains */ 4807/* Setup the mask of cpus configured for isolated domains */
4808static int __init isolated_cpu_setup(char *str) 4808static int __init isolated_cpu_setup(char *str)
@@ -4830,8 +4830,8 @@ __setup ("isolcpus=", isolated_cpu_setup);
4830 * covered by the given span, and will set each group's ->cpumask correctly, 4830 * covered by the given span, and will set each group's ->cpumask correctly,
4831 * and ->cpu_power to 0. 4831 * and ->cpu_power to 0.
4832 */ 4832 */
4833void init_sched_build_groups(struct sched_group groups[], 4833static void init_sched_build_groups(struct sched_group groups[], cpumask_t span,
4834 cpumask_t span, int (*group_fn)(int cpu)) 4834 int (*group_fn)(int cpu))
4835{ 4835{
4836 struct sched_group *first = NULL, *last = NULL; 4836 struct sched_group *first = NULL, *last = NULL;
4837 cpumask_t covered = CPU_MASK_NONE; 4837 cpumask_t covered = CPU_MASK_NONE;
@@ -4864,12 +4864,85 @@ void init_sched_build_groups(struct sched_group groups[],
4864 last->next = first; 4864 last->next = first;
4865} 4865}
4866 4866
4867#define SD_NODES_PER_DOMAIN 16
4867 4868
4868#ifdef ARCH_HAS_SCHED_DOMAIN 4869#ifdef CONFIG_NUMA
4869extern void build_sched_domains(const cpumask_t *cpu_map); 4870/**
4870extern void arch_init_sched_domains(const cpumask_t *cpu_map); 4871 * find_next_best_node - find the next node to include in a sched_domain
4871extern void arch_destroy_sched_domains(const cpumask_t *cpu_map); 4872 * @node: node whose sched_domain we're building
4872#else 4873 * @used_nodes: nodes already in the sched_domain
4874 *
4875 * Find the next node to include in a given scheduling domain. Simply
4876 * finds the closest node not already in the @used_nodes map.
4877 *
4878 * Should use nodemask_t.
4879 */
4880static int find_next_best_node(int node, unsigned long *used_nodes)
4881{
4882 int i, n, val, min_val, best_node = 0;
4883
4884 min_val = INT_MAX;
4885
4886 for (i = 0; i < MAX_NUMNODES; i++) {
4887 /* Start at @node */
4888 n = (node + i) % MAX_NUMNODES;
4889
4890 if (!nr_cpus_node(n))
4891 continue;
4892
4893 /* Skip already used nodes */
4894 if (test_bit(n, used_nodes))
4895 continue;
4896
4897 /* Simple min distance search */
4898 val = node_distance(node, n);
4899
4900 if (val < min_val) {
4901 min_val = val;
4902 best_node = n;
4903 }
4904 }
4905
4906 set_bit(best_node, used_nodes);
4907 return best_node;
4908}
4909
4910/**
4911 * sched_domain_node_span - get a cpumask for a node's sched_domain
4912 * @node: node whose cpumask we're constructing
4913 * @size: number of nodes to include in this span
4914 *
4915 * Given a node, construct a good cpumask for its sched_domain to span. It
4916 * should be one that prevents unnecessary balancing, but also spreads tasks
4917 * out optimally.
4918 */
4919static cpumask_t sched_domain_node_span(int node)
4920{
4921 int i;
4922 cpumask_t span, nodemask;
4923 DECLARE_BITMAP(used_nodes, MAX_NUMNODES);
4924
4925 cpus_clear(span);
4926 bitmap_zero(used_nodes, MAX_NUMNODES);
4927
4928 nodemask = node_to_cpumask(node);
4929 cpus_or(span, span, nodemask);
4930 set_bit(node, used_nodes);
4931
4932 for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
4933 int next_node = find_next_best_node(node, used_nodes);
4934 nodemask = node_to_cpumask(next_node);
4935 cpus_or(span, span, nodemask);
4936 }
4937
4938 return span;
4939}
4940#endif
4941
4942/*
4943 * At the moment, CONFIG_SCHED_SMT is never defined, but leave it in so we
4944 * can switch it on easily if needed.
4945 */
4873#ifdef CONFIG_SCHED_SMT 4946#ifdef CONFIG_SCHED_SMT
4874static DEFINE_PER_CPU(struct sched_domain, cpu_domains); 4947static DEFINE_PER_CPU(struct sched_domain, cpu_domains);
4875static struct sched_group sched_group_cpus[NR_CPUS]; 4948static struct sched_group sched_group_cpus[NR_CPUS];
@@ -4891,36 +4964,20 @@ static int cpu_to_phys_group(int cpu)
4891} 4964}
4892 4965
4893#ifdef CONFIG_NUMA 4966#ifdef CONFIG_NUMA
4894
4895static DEFINE_PER_CPU(struct sched_domain, node_domains);
4896static struct sched_group sched_group_nodes[MAX_NUMNODES];
4897static int cpu_to_node_group(int cpu)
4898{
4899 return cpu_to_node(cpu);
4900}
4901#endif
4902
4903#if defined(CONFIG_SCHED_SMT) && defined(CONFIG_NUMA)
4904/* 4967/*
4905 * The domains setup code relies on siblings not spanning 4968 * The init_sched_build_groups can't handle what we want to do with node
4906 * multiple nodes. Make sure the architecture has a proper 4969 * groups, so roll our own. Now each node has its own list of groups which
4907 * siblings map: 4970 * gets dynamically allocated.
4908 */ 4971 */
4909static void check_sibling_maps(void) 4972static DEFINE_PER_CPU(struct sched_domain, node_domains);
4910{ 4973static struct sched_group *sched_group_nodes[MAX_NUMNODES];
4911 int i, j;
4912 4974
4913 for_each_online_cpu(i) { 4975static DEFINE_PER_CPU(struct sched_domain, allnodes_domains);
4914 for_each_cpu_mask(j, cpu_sibling_map[i]) { 4976static struct sched_group sched_group_allnodes[MAX_NUMNODES];
4915 if (cpu_to_node(i) != cpu_to_node(j)) { 4977
4916 printk(KERN_INFO "warning: CPU %d siblings map " 4978static int cpu_to_allnodes_group(int cpu)
4917 "to different node - isolating " 4979{
4918 "them.\n", i); 4980 return cpu_to_node(cpu);
4919 cpu_sibling_map[i] = cpumask_of_cpu(i);
4920 break;
4921 }
4922 }
4923 }
4924} 4981}
4925#endif 4982#endif
4926 4983
@@ -4928,7 +4985,7 @@ static void check_sibling_maps(void)
4928 * Build sched domains for a given set of cpus and attach the sched domains 4985 * Build sched domains for a given set of cpus and attach the sched domains
4929 * to the individual cpus 4986 * to the individual cpus
4930 */ 4987 */
4931static void build_sched_domains(const cpumask_t *cpu_map) 4988void build_sched_domains(const cpumask_t *cpu_map)
4932{ 4989{
4933 int i; 4990 int i;
4934 4991
@@ -4943,11 +5000,22 @@ static void build_sched_domains(const cpumask_t *cpu_map)
4943 cpus_and(nodemask, nodemask, *cpu_map); 5000 cpus_and(nodemask, nodemask, *cpu_map);
4944 5001
4945#ifdef CONFIG_NUMA 5002#ifdef CONFIG_NUMA
5003 if (num_online_cpus()
5004 > SD_NODES_PER_DOMAIN*cpus_weight(nodemask)) {
5005 sd = &per_cpu(allnodes_domains, i);
5006 *sd = SD_ALLNODES_INIT;
5007 sd->span = *cpu_map;
5008 group = cpu_to_allnodes_group(i);
5009 sd->groups = &sched_group_allnodes[group];
5010 p = sd;
5011 } else
5012 p = NULL;
5013
4946 sd = &per_cpu(node_domains, i); 5014 sd = &per_cpu(node_domains, i);
4947 group = cpu_to_node_group(i);
4948 *sd = SD_NODE_INIT; 5015 *sd = SD_NODE_INIT;
4949 sd->span = *cpu_map; 5016 sd->span = sched_domain_node_span(cpu_to_node(i));
4950 sd->groups = &sched_group_nodes[group]; 5017 sd->parent = p;
5018 cpus_and(sd->span, sd->span, *cpu_map);
4951#endif 5019#endif
4952 5020
4953 p = sd; 5021 p = sd;
@@ -4972,7 +5040,7 @@ static void build_sched_domains(const cpumask_t *cpu_map)
4972 5040
4973#ifdef CONFIG_SCHED_SMT 5041#ifdef CONFIG_SCHED_SMT
4974 /* Set up CPU (sibling) groups */ 5042 /* Set up CPU (sibling) groups */
4975 for_each_online_cpu(i) { 5043 for_each_cpu_mask(i, *cpu_map) {
4976 cpumask_t this_sibling_map = cpu_sibling_map[i]; 5044 cpumask_t this_sibling_map = cpu_sibling_map[i];
4977 cpus_and(this_sibling_map, this_sibling_map, *cpu_map); 5045 cpus_and(this_sibling_map, this_sibling_map, *cpu_map);
4978 if (i != first_cpu(this_sibling_map)) 5046 if (i != first_cpu(this_sibling_map))
@@ -4997,8 +5065,74 @@ static void build_sched_domains(const cpumask_t *cpu_map)
4997 5065
4998#ifdef CONFIG_NUMA 5066#ifdef CONFIG_NUMA
4999 /* Set up node groups */ 5067 /* Set up node groups */
5000 init_sched_build_groups(sched_group_nodes, *cpu_map, 5068 init_sched_build_groups(sched_group_allnodes, *cpu_map,
5001 &cpu_to_node_group); 5069 &cpu_to_allnodes_group);
5070
5071 for (i = 0; i < MAX_NUMNODES; i++) {
5072 /* Set up node groups */
5073 struct sched_group *sg, *prev;
5074 cpumask_t nodemask = node_to_cpumask(i);
5075 cpumask_t domainspan;
5076 cpumask_t covered = CPU_MASK_NONE;
5077 int j;
5078
5079 cpus_and(nodemask, nodemask, *cpu_map);
5080 if (cpus_empty(nodemask))
5081 continue;
5082
5083 domainspan = sched_domain_node_span(i);
5084 cpus_and(domainspan, domainspan, *cpu_map);
5085
5086 sg = kmalloc(sizeof(struct sched_group), GFP_KERNEL);
5087 sched_group_nodes[i] = sg;
5088 for_each_cpu_mask(j, nodemask) {
5089 struct sched_domain *sd;
5090 sd = &per_cpu(node_domains, j);
5091 sd->groups = sg;
5092 if (sd->groups == NULL) {
5093 /* Turn off balancing if we have no groups */
5094 sd->flags = 0;
5095 }
5096 }
5097 if (!sg) {
5098 printk(KERN_WARNING
5099 "Can not alloc domain group for node %d\n", i);
5100 continue;
5101 }
5102 sg->cpu_power = 0;
5103 sg->cpumask = nodemask;
5104 cpus_or(covered, covered, nodemask);
5105 prev = sg;
5106
5107 for (j = 0; j < MAX_NUMNODES; j++) {
5108 cpumask_t tmp, notcovered;
5109 int n = (i + j) % MAX_NUMNODES;
5110
5111 cpus_complement(notcovered, covered);
5112 cpus_and(tmp, notcovered, *cpu_map);
5113 cpus_and(tmp, tmp, domainspan);
5114 if (cpus_empty(tmp))
5115 break;
5116
5117 nodemask = node_to_cpumask(n);
5118 cpus_and(tmp, tmp, nodemask);
5119 if (cpus_empty(tmp))
5120 continue;
5121
5122 sg = kmalloc(sizeof(struct sched_group), GFP_KERNEL);
5123 if (!sg) {
5124 printk(KERN_WARNING
5125 "Can not alloc domain group for node %d\n", j);
5126 break;
5127 }
5128 sg->cpu_power = 0;
5129 sg->cpumask = tmp;
5130 cpus_or(covered, covered, tmp);
5131 prev->next = sg;
5132 prev = sg;
5133 }
5134 prev->next = sched_group_nodes[i];
5135 }
5002#endif 5136#endif
5003 5137
5004 /* Calculate CPU power for physical packages and nodes */ 5138 /* Calculate CPU power for physical packages and nodes */
@@ -5017,14 +5151,46 @@ static void build_sched_domains(const cpumask_t *cpu_map)
5017 sd->groups->cpu_power = power; 5151 sd->groups->cpu_power = power;
5018 5152
5019#ifdef CONFIG_NUMA 5153#ifdef CONFIG_NUMA
5020 if (i == first_cpu(sd->groups->cpumask)) { 5154 sd = &per_cpu(allnodes_domains, i);
5021 /* Only add "power" once for each physical package. */ 5155 if (sd->groups) {
5022 sd = &per_cpu(node_domains, i); 5156 power = SCHED_LOAD_SCALE + SCHED_LOAD_SCALE *
5023 sd->groups->cpu_power += power; 5157 (cpus_weight(sd->groups->cpumask)-1) / 10;
5158 sd->groups->cpu_power = power;
5024 } 5159 }
5025#endif 5160#endif
5026 } 5161 }
5027 5162
5163#ifdef CONFIG_NUMA
5164 for (i = 0; i < MAX_NUMNODES; i++) {
5165 struct sched_group *sg = sched_group_nodes[i];
5166 int j;
5167
5168 if (sg == NULL)
5169 continue;
5170next_sg:
5171 for_each_cpu_mask(j, sg->cpumask) {
5172 struct sched_domain *sd;
5173 int power;
5174
5175 sd = &per_cpu(phys_domains, j);
5176 if (j != first_cpu(sd->groups->cpumask)) {
5177 /*
5178 * Only add "power" once for each
5179 * physical package.
5180 */
5181 continue;
5182 }
5183 power = SCHED_LOAD_SCALE + SCHED_LOAD_SCALE *
5184 (cpus_weight(sd->groups->cpumask)-1) / 10;
5185
5186 sg->cpu_power += power;
5187 }
5188 sg = sg->next;
5189 if (sg != sched_group_nodes[i])
5190 goto next_sg;
5191 }
5192#endif
5193
5028 /* Attach the domains */ 5194 /* Attach the domains */
5029 for_each_cpu_mask(i, *cpu_map) { 5195 for_each_cpu_mask(i, *cpu_map) {
5030 struct sched_domain *sd; 5196 struct sched_domain *sd;
@@ -5039,13 +5205,10 @@ static void build_sched_domains(const cpumask_t *cpu_map)
5039/* 5205/*
5040 * Set up scheduler domains and groups. Callers must hold the hotplug lock. 5206 * Set up scheduler domains and groups. Callers must hold the hotplug lock.
5041 */ 5207 */
5042static void arch_init_sched_domains(cpumask_t *cpu_map) 5208static void arch_init_sched_domains(const cpumask_t *cpu_map)
5043{ 5209{
5044 cpumask_t cpu_default_map; 5210 cpumask_t cpu_default_map;
5045 5211
5046#if defined(CONFIG_SCHED_SMT) && defined(CONFIG_NUMA)
5047 check_sibling_maps();
5048#endif
5049 /* 5212 /*
5050 * Setup mask for cpus without special case scheduling requirements. 5213 * Setup mask for cpus without special case scheduling requirements.
5051 * For now this just excludes isolated cpus, but could be used to 5214 * For now this just excludes isolated cpus, but could be used to
@@ -5058,10 +5221,29 @@ static void arch_init_sched_domains(cpumask_t *cpu_map)
5058 5221
5059static void arch_destroy_sched_domains(const cpumask_t *cpu_map) 5222static void arch_destroy_sched_domains(const cpumask_t *cpu_map)
5060{ 5223{
5061 /* Do nothing: everything is statically allocated. */ 5224#ifdef CONFIG_NUMA
5062} 5225 int i;
5226 for (i = 0; i < MAX_NUMNODES; i++) {
5227 cpumask_t nodemask = node_to_cpumask(i);
5228 struct sched_group *oldsg, *sg = sched_group_nodes[i];
5063 5229
5064#endif /* ARCH_HAS_SCHED_DOMAIN */ 5230 cpus_and(nodemask, nodemask, *cpu_map);
5231 if (cpus_empty(nodemask))
5232 continue;
5233
5234 if (sg == NULL)
5235 continue;
5236 sg = sg->next;
5237next_sg:
5238 oldsg = sg;
5239 sg = sg->next;
5240 kfree(oldsg);
5241 if (oldsg != sched_group_nodes[i])
5242 goto next_sg;
5243 sched_group_nodes[i] = NULL;
5244 }
5245#endif
5246}
5065 5247
5066/* 5248/*
5067 * Detach sched domains from a group of cpus specified in cpu_map 5249 * Detach sched domains from a group of cpus specified in cpu_map