Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2 | /* |
| 3 | * Scheduler topology setup/handling methods |
| 4 | */ |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 5 | #include "sched.h" |
| 6 | |
| 7 | DEFINE_MUTEX(sched_domains_mutex); |
| 8 | |
| 9 | /* Protected by sched_domains_mutex: */ |
zhong jiang | ace8031 | 2018-08-03 20:37:32 +0800 | [diff] [blame] | 10 | static cpumask_var_t sched_domains_tmpmask; |
| 11 | static cpumask_var_t sched_domains_tmpmask2; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 12 | |
| 13 | #ifdef CONFIG_SCHED_DEBUG |
| 14 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 15 | static int __init sched_debug_setup(char *str) |
| 16 | { |
Peter Zijlstra | 9469eb0 | 2017-09-07 17:03:53 +0200 | [diff] [blame] | 17 | sched_debug_enabled = true; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 18 | |
| 19 | return 0; |
| 20 | } |
| 21 | early_param("sched_debug", sched_debug_setup); |
| 22 | |
| 23 | static inline bool sched_debug(void) |
| 24 | { |
| 25 | return sched_debug_enabled; |
| 26 | } |
| 27 | |
| 28 | static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, |
| 29 | struct cpumask *groupmask) |
| 30 | { |
| 31 | struct sched_group *group = sd->groups; |
| 32 | |
| 33 | cpumask_clear(groupmask); |
| 34 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 35 | printk(KERN_DEBUG "%*s domain-%d: ", level, "", level); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 36 | |
| 37 | if (!(sd->flags & SD_LOAD_BALANCE)) { |
| 38 | printk("does not load-balance\n"); |
| 39 | if (sd->parent) |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 40 | printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain has parent"); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 41 | return -1; |
| 42 | } |
| 43 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 44 | printk(KERN_CONT "span=%*pbl level=%s\n", |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 45 | cpumask_pr_args(sched_domain_span(sd)), sd->name); |
| 46 | |
| 47 | if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) { |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 48 | printk(KERN_ERR "ERROR: domain->span does not contain CPU%d\n", cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 49 | } |
Yi Wang | 6cd0c58 | 2018-07-23 12:19:07 +0800 | [diff] [blame] | 50 | if (group && !cpumask_test_cpu(cpu, sched_group_span(group))) { |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 51 | printk(KERN_ERR "ERROR: domain->groups does not contain CPU%d\n", cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 52 | } |
| 53 | |
| 54 | printk(KERN_DEBUG "%*s groups:", level + 1, ""); |
| 55 | do { |
| 56 | if (!group) { |
| 57 | printk("\n"); |
| 58 | printk(KERN_ERR "ERROR: group is NULL\n"); |
| 59 | break; |
| 60 | } |
| 61 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 62 | if (!cpumask_weight(sched_group_span(group))) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 63 | printk(KERN_CONT "\n"); |
| 64 | printk(KERN_ERR "ERROR: empty group\n"); |
| 65 | break; |
| 66 | } |
| 67 | |
| 68 | if (!(sd->flags & SD_OVERLAP) && |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 69 | cpumask_intersects(groupmask, sched_group_span(group))) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 70 | printk(KERN_CONT "\n"); |
| 71 | printk(KERN_ERR "ERROR: repeated CPUs\n"); |
| 72 | break; |
| 73 | } |
| 74 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 75 | cpumask_or(groupmask, groupmask, sched_group_span(group)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 76 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 77 | printk(KERN_CONT " %d:{ span=%*pbl", |
| 78 | group->sgc->id, |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 79 | cpumask_pr_args(sched_group_span(group))); |
Peter Zijlstra | b0151c2 | 2017-04-14 17:29:16 +0200 | [diff] [blame] | 80 | |
Peter Zijlstra | af21812 | 2017-05-01 08:51:05 +0200 | [diff] [blame] | 81 | if ((sd->flags & SD_OVERLAP) && |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 82 | !cpumask_equal(group_balance_mask(group), sched_group_span(group))) { |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 83 | printk(KERN_CONT " mask=%*pbl", |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 84 | cpumask_pr_args(group_balance_mask(group))); |
Peter Zijlstra | b0151c2 | 2017-04-14 17:29:16 +0200 | [diff] [blame] | 85 | } |
| 86 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 87 | if (group->sgc->capacity != SCHED_CAPACITY_SCALE) |
| 88 | printk(KERN_CONT " cap=%lu", group->sgc->capacity); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 89 | |
Peter Zijlstra | a420b06 | 2017-04-14 18:20:48 +0200 | [diff] [blame] | 90 | if (group == sd->groups && sd->child && |
| 91 | !cpumask_equal(sched_domain_span(sd->child), |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 92 | sched_group_span(group))) { |
Peter Zijlstra | a420b06 | 2017-04-14 18:20:48 +0200 | [diff] [blame] | 93 | printk(KERN_ERR "ERROR: domain->groups does not match domain->child\n"); |
| 94 | } |
| 95 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 96 | printk(KERN_CONT " }"); |
| 97 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 98 | group = group->next; |
Peter Zijlstra | b0151c2 | 2017-04-14 17:29:16 +0200 | [diff] [blame] | 99 | |
| 100 | if (group != sd->groups) |
| 101 | printk(KERN_CONT ","); |
| 102 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 103 | } while (group != sd->groups); |
| 104 | printk(KERN_CONT "\n"); |
| 105 | |
| 106 | if (!cpumask_equal(sched_domain_span(sd), groupmask)) |
| 107 | printk(KERN_ERR "ERROR: groups don't span domain->span\n"); |
| 108 | |
| 109 | if (sd->parent && |
| 110 | !cpumask_subset(groupmask, sched_domain_span(sd->parent))) |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 111 | printk(KERN_ERR "ERROR: parent span is not a superset of domain->span\n"); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 112 | return 0; |
| 113 | } |
| 114 | |
| 115 | static void sched_domain_debug(struct sched_domain *sd, int cpu) |
| 116 | { |
| 117 | int level = 0; |
| 118 | |
| 119 | if (!sched_debug_enabled) |
| 120 | return; |
| 121 | |
| 122 | if (!sd) { |
| 123 | printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu); |
| 124 | return; |
| 125 | } |
| 126 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 127 | printk(KERN_DEBUG "CPU%d attaching sched-domain(s):\n", cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 128 | |
| 129 | for (;;) { |
| 130 | if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) |
| 131 | break; |
| 132 | level++; |
| 133 | sd = sd->parent; |
| 134 | if (!sd) |
| 135 | break; |
| 136 | } |
| 137 | } |
| 138 | #else /* !CONFIG_SCHED_DEBUG */ |
| 139 | |
| 140 | # define sched_debug_enabled 0 |
| 141 | # define sched_domain_debug(sd, cpu) do { } while (0) |
| 142 | static inline bool sched_debug(void) |
| 143 | { |
| 144 | return false; |
| 145 | } |
| 146 | #endif /* CONFIG_SCHED_DEBUG */ |
| 147 | |
| 148 | static int sd_degenerate(struct sched_domain *sd) |
| 149 | { |
| 150 | if (cpumask_weight(sched_domain_span(sd)) == 1) |
| 151 | return 1; |
| 152 | |
| 153 | /* Following flags need at least 2 groups */ |
| 154 | if (sd->flags & (SD_LOAD_BALANCE | |
| 155 | SD_BALANCE_NEWIDLE | |
| 156 | SD_BALANCE_FORK | |
| 157 | SD_BALANCE_EXEC | |
| 158 | SD_SHARE_CPUCAPACITY | |
| 159 | SD_ASYM_CPUCAPACITY | |
| 160 | SD_SHARE_PKG_RESOURCES | |
| 161 | SD_SHARE_POWERDOMAIN)) { |
| 162 | if (sd->groups != sd->groups->next) |
| 163 | return 0; |
| 164 | } |
| 165 | |
| 166 | /* Following flags don't use groups */ |
| 167 | if (sd->flags & (SD_WAKE_AFFINE)) |
| 168 | return 0; |
| 169 | |
| 170 | return 1; |
| 171 | } |
| 172 | |
| 173 | static int |
| 174 | sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) |
| 175 | { |
| 176 | unsigned long cflags = sd->flags, pflags = parent->flags; |
| 177 | |
| 178 | if (sd_degenerate(parent)) |
| 179 | return 1; |
| 180 | |
| 181 | if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent))) |
| 182 | return 0; |
| 183 | |
| 184 | /* Flags needing groups don't count if only 1 group in parent */ |
| 185 | if (parent->groups == parent->groups->next) { |
| 186 | pflags &= ~(SD_LOAD_BALANCE | |
| 187 | SD_BALANCE_NEWIDLE | |
| 188 | SD_BALANCE_FORK | |
| 189 | SD_BALANCE_EXEC | |
| 190 | SD_ASYM_CPUCAPACITY | |
| 191 | SD_SHARE_CPUCAPACITY | |
| 192 | SD_SHARE_PKG_RESOURCES | |
| 193 | SD_PREFER_SIBLING | |
| 194 | SD_SHARE_POWERDOMAIN); |
| 195 | if (nr_node_ids == 1) |
| 196 | pflags &= ~SD_SERIALIZE; |
| 197 | } |
| 198 | if (~cflags & pflags) |
| 199 | return 0; |
| 200 | |
| 201 | return 1; |
| 202 | } |
| 203 | |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 204 | #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) |
Peter Zijlstra | f8a696f | 2018-12-05 11:23:56 +0100 | [diff] [blame] | 205 | DEFINE_STATIC_KEY_FALSE(sched_energy_present); |
Quentin Perret | 8d5d0cf | 2018-12-03 09:56:23 +0000 | [diff] [blame] | 206 | unsigned int sysctl_sched_energy_aware = 1; |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 207 | DEFINE_MUTEX(sched_energy_mutex); |
| 208 | bool sched_energy_update; |
| 209 | |
Quentin Perret | 8d5d0cf | 2018-12-03 09:56:23 +0000 | [diff] [blame] | 210 | #ifdef CONFIG_PROC_SYSCTL |
| 211 | int sched_energy_aware_handler(struct ctl_table *table, int write, |
| 212 | void __user *buffer, size_t *lenp, loff_t *ppos) |
| 213 | { |
| 214 | int ret, state; |
| 215 | |
| 216 | if (write && !capable(CAP_SYS_ADMIN)) |
| 217 | return -EPERM; |
| 218 | |
| 219 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
| 220 | if (!ret && write) { |
| 221 | state = static_branch_unlikely(&sched_energy_present); |
| 222 | if (state != sysctl_sched_energy_aware) { |
| 223 | mutex_lock(&sched_energy_mutex); |
| 224 | sched_energy_update = 1; |
| 225 | rebuild_sched_domains(); |
| 226 | sched_energy_update = 0; |
| 227 | mutex_unlock(&sched_energy_mutex); |
| 228 | } |
| 229 | } |
| 230 | |
| 231 | return ret; |
| 232 | } |
| 233 | #endif |
| 234 | |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 235 | static void free_pd(struct perf_domain *pd) |
| 236 | { |
| 237 | struct perf_domain *tmp; |
| 238 | |
| 239 | while (pd) { |
| 240 | tmp = pd->next; |
| 241 | kfree(pd); |
| 242 | pd = tmp; |
| 243 | } |
| 244 | } |
| 245 | |
| 246 | static struct perf_domain *find_pd(struct perf_domain *pd, int cpu) |
| 247 | { |
| 248 | while (pd) { |
| 249 | if (cpumask_test_cpu(cpu, perf_domain_span(pd))) |
| 250 | return pd; |
| 251 | pd = pd->next; |
| 252 | } |
| 253 | |
| 254 | return NULL; |
| 255 | } |
| 256 | |
| 257 | static struct perf_domain *pd_init(int cpu) |
| 258 | { |
| 259 | struct em_perf_domain *obj = em_cpu_get(cpu); |
| 260 | struct perf_domain *pd; |
| 261 | |
| 262 | if (!obj) { |
| 263 | if (sched_debug()) |
| 264 | pr_info("%s: no EM found for CPU%d\n", __func__, cpu); |
| 265 | return NULL; |
| 266 | } |
| 267 | |
| 268 | pd = kzalloc(sizeof(*pd), GFP_KERNEL); |
| 269 | if (!pd) |
| 270 | return NULL; |
| 271 | pd->em_pd = obj; |
| 272 | |
| 273 | return pd; |
| 274 | } |
| 275 | |
| 276 | static void perf_domain_debug(const struct cpumask *cpu_map, |
| 277 | struct perf_domain *pd) |
| 278 | { |
| 279 | if (!sched_debug() || !pd) |
| 280 | return; |
| 281 | |
| 282 | printk(KERN_DEBUG "root_domain %*pbl:", cpumask_pr_args(cpu_map)); |
| 283 | |
| 284 | while (pd) { |
| 285 | printk(KERN_CONT " pd%d:{ cpus=%*pbl nr_cstate=%d }", |
| 286 | cpumask_first(perf_domain_span(pd)), |
| 287 | cpumask_pr_args(perf_domain_span(pd)), |
| 288 | em_pd_nr_cap_states(pd->em_pd)); |
| 289 | pd = pd->next; |
| 290 | } |
| 291 | |
| 292 | printk(KERN_CONT "\n"); |
| 293 | } |
| 294 | |
| 295 | static void destroy_perf_domain_rcu(struct rcu_head *rp) |
| 296 | { |
| 297 | struct perf_domain *pd; |
| 298 | |
| 299 | pd = container_of(rp, struct perf_domain, rcu); |
| 300 | free_pd(pd); |
| 301 | } |
| 302 | |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 303 | static void sched_energy_set(bool has_eas) |
| 304 | { |
| 305 | if (!has_eas && static_branch_unlikely(&sched_energy_present)) { |
| 306 | if (sched_debug()) |
| 307 | pr_info("%s: stopping EAS\n", __func__); |
| 308 | static_branch_disable_cpuslocked(&sched_energy_present); |
| 309 | } else if (has_eas && !static_branch_unlikely(&sched_energy_present)) { |
| 310 | if (sched_debug()) |
| 311 | pr_info("%s: starting EAS\n", __func__); |
| 312 | static_branch_enable_cpuslocked(&sched_energy_present); |
| 313 | } |
| 314 | } |
| 315 | |
Quentin Perret | b68a4c0 | 2018-12-03 09:56:20 +0000 | [diff] [blame] | 316 | /* |
| 317 | * EAS can be used on a root domain if it meets all the following conditions: |
| 318 | * 1. an Energy Model (EM) is available; |
| 319 | * 2. the SD_ASYM_CPUCAPACITY flag is set in the sched_domain hierarchy. |
| 320 | * 3. the EM complexity is low enough to keep scheduling overheads low; |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 321 | * 4. schedutil is driving the frequency of all CPUs of the rd; |
Quentin Perret | b68a4c0 | 2018-12-03 09:56:20 +0000 | [diff] [blame] | 322 | * |
| 323 | * The complexity of the Energy Model is defined as: |
| 324 | * |
| 325 | * C = nr_pd * (nr_cpus + nr_cs) |
| 326 | * |
| 327 | * with parameters defined as: |
| 328 | * - nr_pd: the number of performance domains |
| 329 | * - nr_cpus: the number of CPUs |
| 330 | * - nr_cs: the sum of the number of capacity states of all performance |
| 331 | * domains (for example, on a system with 2 performance domains, |
| 332 | * with 10 capacity states each, nr_cs = 2 * 10 = 20). |
| 333 | * |
| 334 | * It is generally not a good idea to use such a model in the wake-up path on |
| 335 | * very complex platforms because of the associated scheduling overheads. The |
| 336 | * arbitrary constraint below prevents that. It makes EAS usable up to 16 CPUs |
| 337 | * with per-CPU DVFS and less than 8 capacity states each, for example. |
| 338 | */ |
| 339 | #define EM_MAX_COMPLEXITY 2048 |
| 340 | |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 341 | extern struct cpufreq_governor schedutil_gov; |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 342 | static bool build_perf_domains(const struct cpumask *cpu_map) |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 343 | { |
Quentin Perret | b68a4c0 | 2018-12-03 09:56:20 +0000 | [diff] [blame] | 344 | int i, nr_pd = 0, nr_cs = 0, nr_cpus = cpumask_weight(cpu_map); |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 345 | struct perf_domain *pd = NULL, *tmp; |
| 346 | int cpu = cpumask_first(cpu_map); |
| 347 | struct root_domain *rd = cpu_rq(cpu)->rd; |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 348 | struct cpufreq_policy *policy; |
| 349 | struct cpufreq_governor *gov; |
Quentin Perret | b68a4c0 | 2018-12-03 09:56:20 +0000 | [diff] [blame] | 350 | |
Quentin Perret | 8d5d0cf | 2018-12-03 09:56:23 +0000 | [diff] [blame] | 351 | if (!sysctl_sched_energy_aware) |
| 352 | goto free; |
| 353 | |
Quentin Perret | b68a4c0 | 2018-12-03 09:56:20 +0000 | [diff] [blame] | 354 | /* EAS is enabled for asymmetric CPU capacity topologies. */ |
| 355 | if (!per_cpu(sd_asym_cpucapacity, cpu)) { |
| 356 | if (sched_debug()) { |
| 357 | pr_info("rd %*pbl: CPUs do not have asymmetric capacities\n", |
| 358 | cpumask_pr_args(cpu_map)); |
| 359 | } |
| 360 | goto free; |
| 361 | } |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 362 | |
| 363 | for_each_cpu(i, cpu_map) { |
| 364 | /* Skip already covered CPUs. */ |
| 365 | if (find_pd(pd, i)) |
| 366 | continue; |
| 367 | |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 368 | /* Do not attempt EAS if schedutil is not being used. */ |
| 369 | policy = cpufreq_cpu_get(i); |
| 370 | if (!policy) |
| 371 | goto free; |
| 372 | gov = policy->governor; |
| 373 | cpufreq_cpu_put(policy); |
| 374 | if (gov != &schedutil_gov) { |
| 375 | if (rd->pd) |
| 376 | pr_warn("rd %*pbl: Disabling EAS, schedutil is mandatory\n", |
| 377 | cpumask_pr_args(cpu_map)); |
| 378 | goto free; |
| 379 | } |
| 380 | |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 381 | /* Create the new pd and add it to the local list. */ |
| 382 | tmp = pd_init(i); |
| 383 | if (!tmp) |
| 384 | goto free; |
| 385 | tmp->next = pd; |
| 386 | pd = tmp; |
Quentin Perret | b68a4c0 | 2018-12-03 09:56:20 +0000 | [diff] [blame] | 387 | |
| 388 | /* |
| 389 | * Count performance domains and capacity states for the |
| 390 | * complexity check. |
| 391 | */ |
| 392 | nr_pd++; |
| 393 | nr_cs += em_pd_nr_cap_states(pd->em_pd); |
| 394 | } |
| 395 | |
| 396 | /* Bail out if the Energy Model complexity is too high. */ |
| 397 | if (nr_pd * (nr_cs + nr_cpus) > EM_MAX_COMPLEXITY) { |
| 398 | WARN(1, "rd %*pbl: Failed to start EAS, EM complexity is too high\n", |
| 399 | cpumask_pr_args(cpu_map)); |
| 400 | goto free; |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 401 | } |
| 402 | |
| 403 | perf_domain_debug(cpu_map, pd); |
| 404 | |
| 405 | /* Attach the new list of performance domains to the root domain. */ |
| 406 | tmp = rd->pd; |
| 407 | rcu_assign_pointer(rd->pd, pd); |
| 408 | if (tmp) |
| 409 | call_rcu(&tmp->rcu, destroy_perf_domain_rcu); |
| 410 | |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 411 | return !!pd; |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 412 | |
| 413 | free: |
| 414 | free_pd(pd); |
| 415 | tmp = rd->pd; |
| 416 | rcu_assign_pointer(rd->pd, NULL); |
| 417 | if (tmp) |
| 418 | call_rcu(&tmp->rcu, destroy_perf_domain_rcu); |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 419 | |
| 420 | return false; |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 421 | } |
| 422 | #else |
| 423 | static void free_pd(struct perf_domain *pd) { } |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 424 | #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL*/ |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 425 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 426 | static void free_rootdomain(struct rcu_head *rcu) |
| 427 | { |
| 428 | struct root_domain *rd = container_of(rcu, struct root_domain, rcu); |
| 429 | |
| 430 | cpupri_cleanup(&rd->cpupri); |
| 431 | cpudl_cleanup(&rd->cpudl); |
| 432 | free_cpumask_var(rd->dlo_mask); |
| 433 | free_cpumask_var(rd->rto_mask); |
| 434 | free_cpumask_var(rd->online); |
| 435 | free_cpumask_var(rd->span); |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 436 | free_pd(rd->pd); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 437 | kfree(rd); |
| 438 | } |
| 439 | |
| 440 | void rq_attach_root(struct rq *rq, struct root_domain *rd) |
| 441 | { |
| 442 | struct root_domain *old_rd = NULL; |
| 443 | unsigned long flags; |
| 444 | |
| 445 | raw_spin_lock_irqsave(&rq->lock, flags); |
| 446 | |
| 447 | if (rq->rd) { |
| 448 | old_rd = rq->rd; |
| 449 | |
| 450 | if (cpumask_test_cpu(rq->cpu, old_rd->online)) |
| 451 | set_rq_offline(rq); |
| 452 | |
| 453 | cpumask_clear_cpu(rq->cpu, old_rd->span); |
| 454 | |
| 455 | /* |
| 456 | * If we dont want to free the old_rd yet then |
| 457 | * set old_rd to NULL to skip the freeing later |
| 458 | * in this function: |
| 459 | */ |
| 460 | if (!atomic_dec_and_test(&old_rd->refcount)) |
| 461 | old_rd = NULL; |
| 462 | } |
| 463 | |
| 464 | atomic_inc(&rd->refcount); |
| 465 | rq->rd = rd; |
| 466 | |
| 467 | cpumask_set_cpu(rq->cpu, rd->span); |
| 468 | if (cpumask_test_cpu(rq->cpu, cpu_active_mask)) |
| 469 | set_rq_online(rq); |
| 470 | |
| 471 | raw_spin_unlock_irqrestore(&rq->lock, flags); |
| 472 | |
| 473 | if (old_rd) |
Paul E. McKenney | 337e9b0 | 2018-11-06 19:10:53 -0800 | [diff] [blame] | 474 | call_rcu(&old_rd->rcu, free_rootdomain); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 475 | } |
| 476 | |
Steven Rostedt (VMware) | 364f566 | 2018-01-23 20:45:38 -0500 | [diff] [blame] | 477 | void sched_get_rd(struct root_domain *rd) |
| 478 | { |
| 479 | atomic_inc(&rd->refcount); |
| 480 | } |
| 481 | |
| 482 | void sched_put_rd(struct root_domain *rd) |
| 483 | { |
| 484 | if (!atomic_dec_and_test(&rd->refcount)) |
| 485 | return; |
| 486 | |
Paul E. McKenney | 337e9b0 | 2018-11-06 19:10:53 -0800 | [diff] [blame] | 487 | call_rcu(&rd->rcu, free_rootdomain); |
Steven Rostedt (VMware) | 364f566 | 2018-01-23 20:45:38 -0500 | [diff] [blame] | 488 | } |
| 489 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 490 | static int init_rootdomain(struct root_domain *rd) |
| 491 | { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 492 | if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL)) |
| 493 | goto out; |
| 494 | if (!zalloc_cpumask_var(&rd->online, GFP_KERNEL)) |
| 495 | goto free_span; |
| 496 | if (!zalloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL)) |
| 497 | goto free_online; |
| 498 | if (!zalloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) |
| 499 | goto free_dlo_mask; |
| 500 | |
Steven Rostedt (Red Hat) | 4bdced5 | 2017-10-06 14:05:04 -0400 | [diff] [blame] | 501 | #ifdef HAVE_RT_PUSH_IPI |
| 502 | rd->rto_cpu = -1; |
| 503 | raw_spin_lock_init(&rd->rto_lock); |
| 504 | init_irq_work(&rd->rto_push_work, rto_push_irq_work_func); |
| 505 | #endif |
| 506 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 507 | init_dl_bw(&rd->dl_bw); |
| 508 | if (cpudl_init(&rd->cpudl) != 0) |
| 509 | goto free_rto_mask; |
| 510 | |
| 511 | if (cpupri_init(&rd->cpupri) != 0) |
| 512 | goto free_cpudl; |
| 513 | return 0; |
| 514 | |
| 515 | free_cpudl: |
| 516 | cpudl_cleanup(&rd->cpudl); |
| 517 | free_rto_mask: |
| 518 | free_cpumask_var(rd->rto_mask); |
| 519 | free_dlo_mask: |
| 520 | free_cpumask_var(rd->dlo_mask); |
| 521 | free_online: |
| 522 | free_cpumask_var(rd->online); |
| 523 | free_span: |
| 524 | free_cpumask_var(rd->span); |
| 525 | out: |
| 526 | return -ENOMEM; |
| 527 | } |
| 528 | |
| 529 | /* |
| 530 | * By default the system creates a single root-domain with all CPUs as |
| 531 | * members (mimicking the global state we have today). |
| 532 | */ |
| 533 | struct root_domain def_root_domain; |
| 534 | |
| 535 | void init_defrootdomain(void) |
| 536 | { |
| 537 | init_rootdomain(&def_root_domain); |
| 538 | |
| 539 | atomic_set(&def_root_domain.refcount, 1); |
| 540 | } |
| 541 | |
| 542 | static struct root_domain *alloc_rootdomain(void) |
| 543 | { |
| 544 | struct root_domain *rd; |
| 545 | |
Viresh Kumar | 4d13a06 | 2017-04-13 14:45:48 +0530 | [diff] [blame] | 546 | rd = kzalloc(sizeof(*rd), GFP_KERNEL); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 547 | if (!rd) |
| 548 | return NULL; |
| 549 | |
| 550 | if (init_rootdomain(rd) != 0) { |
| 551 | kfree(rd); |
| 552 | return NULL; |
| 553 | } |
| 554 | |
| 555 | return rd; |
| 556 | } |
| 557 | |
| 558 | static void free_sched_groups(struct sched_group *sg, int free_sgc) |
| 559 | { |
| 560 | struct sched_group *tmp, *first; |
| 561 | |
| 562 | if (!sg) |
| 563 | return; |
| 564 | |
| 565 | first = sg; |
| 566 | do { |
| 567 | tmp = sg->next; |
| 568 | |
| 569 | if (free_sgc && atomic_dec_and_test(&sg->sgc->ref)) |
| 570 | kfree(sg->sgc); |
| 571 | |
Shu Wang | 213c5a4 | 2017-08-10 15:52:16 +0800 | [diff] [blame] | 572 | if (atomic_dec_and_test(&sg->ref)) |
| 573 | kfree(sg); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 574 | sg = tmp; |
| 575 | } while (sg != first); |
| 576 | } |
| 577 | |
| 578 | static void destroy_sched_domain(struct sched_domain *sd) |
| 579 | { |
| 580 | /* |
Peter Zijlstra | a090c4f | 2017-08-21 15:42:52 +0200 | [diff] [blame] | 581 | * A normal sched domain may have multiple group references, an |
| 582 | * overlapping domain, having private groups, only one. Iterate, |
| 583 | * dropping group/capacity references, freeing where none remain. |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 584 | */ |
Shu Wang | 213c5a4 | 2017-08-10 15:52:16 +0800 | [diff] [blame] | 585 | free_sched_groups(sd->groups, 1); |
| 586 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 587 | if (sd->shared && atomic_dec_and_test(&sd->shared->ref)) |
| 588 | kfree(sd->shared); |
| 589 | kfree(sd); |
| 590 | } |
| 591 | |
| 592 | static void destroy_sched_domains_rcu(struct rcu_head *rcu) |
| 593 | { |
| 594 | struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu); |
| 595 | |
| 596 | while (sd) { |
| 597 | struct sched_domain *parent = sd->parent; |
| 598 | destroy_sched_domain(sd); |
| 599 | sd = parent; |
| 600 | } |
| 601 | } |
| 602 | |
| 603 | static void destroy_sched_domains(struct sched_domain *sd) |
| 604 | { |
| 605 | if (sd) |
| 606 | call_rcu(&sd->rcu, destroy_sched_domains_rcu); |
| 607 | } |
| 608 | |
| 609 | /* |
| 610 | * Keep a special pointer to the highest sched_domain that has |
| 611 | * SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this |
| 612 | * allows us to avoid some pointer chasing select_idle_sibling(). |
| 613 | * |
| 614 | * Also keep a unique ID per domain (we use the first CPU number in |
| 615 | * the cpumask of the domain), this allows us to quickly tell if |
| 616 | * two CPUs are in the same cache domain, see cpus_share_cache(). |
| 617 | */ |
Joel Fernandes (Google) | 994aeb7 | 2019-03-20 20:34:24 -0400 | [diff] [blame] | 618 | DEFINE_PER_CPU(struct sched_domain __rcu *, sd_llc); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 619 | DEFINE_PER_CPU(int, sd_llc_size); |
| 620 | DEFINE_PER_CPU(int, sd_llc_id); |
Joel Fernandes (Google) | 994aeb7 | 2019-03-20 20:34:24 -0400 | [diff] [blame] | 621 | DEFINE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); |
| 622 | DEFINE_PER_CPU(struct sched_domain __rcu *, sd_numa); |
| 623 | DEFINE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); |
| 624 | DEFINE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); |
Morten Rasmussen | df054e8 | 2018-07-04 11:17:39 +0100 | [diff] [blame] | 625 | DEFINE_STATIC_KEY_FALSE(sched_asym_cpucapacity); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 626 | |
| 627 | static void update_top_cache_domain(int cpu) |
| 628 | { |
| 629 | struct sched_domain_shared *sds = NULL; |
| 630 | struct sched_domain *sd; |
| 631 | int id = cpu; |
| 632 | int size = 1; |
| 633 | |
| 634 | sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES); |
| 635 | if (sd) { |
| 636 | id = cpumask_first(sched_domain_span(sd)); |
| 637 | size = cpumask_weight(sched_domain_span(sd)); |
| 638 | sds = sd->shared; |
| 639 | } |
| 640 | |
| 641 | rcu_assign_pointer(per_cpu(sd_llc, cpu), sd); |
| 642 | per_cpu(sd_llc_size, cpu) = size; |
| 643 | per_cpu(sd_llc_id, cpu) = id; |
| 644 | rcu_assign_pointer(per_cpu(sd_llc_shared, cpu), sds); |
| 645 | |
| 646 | sd = lowest_flag_domain(cpu, SD_NUMA); |
| 647 | rcu_assign_pointer(per_cpu(sd_numa, cpu), sd); |
| 648 | |
| 649 | sd = highest_flag_domain(cpu, SD_ASYM_PACKING); |
Quentin Perret | 011b27b | 2018-12-03 09:56:19 +0000 | [diff] [blame] | 650 | rcu_assign_pointer(per_cpu(sd_asym_packing, cpu), sd); |
| 651 | |
| 652 | sd = lowest_flag_domain(cpu, SD_ASYM_CPUCAPACITY); |
| 653 | rcu_assign_pointer(per_cpu(sd_asym_cpucapacity, cpu), sd); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 654 | } |
| 655 | |
| 656 | /* |
| 657 | * Attach the domain 'sd' to 'cpu' as its base domain. Callers must |
| 658 | * hold the hotplug lock. |
| 659 | */ |
| 660 | static void |
| 661 | cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) |
| 662 | { |
| 663 | struct rq *rq = cpu_rq(cpu); |
| 664 | struct sched_domain *tmp; |
| 665 | |
| 666 | /* Remove the sched domains which do not contribute to scheduling. */ |
| 667 | for (tmp = sd; tmp; ) { |
| 668 | struct sched_domain *parent = tmp->parent; |
| 669 | if (!parent) |
| 670 | break; |
| 671 | |
| 672 | if (sd_parent_degenerate(tmp, parent)) { |
| 673 | tmp->parent = parent->parent; |
| 674 | if (parent->parent) |
| 675 | parent->parent->child = tmp; |
| 676 | /* |
| 677 | * Transfer SD_PREFER_SIBLING down in case of a |
| 678 | * degenerate parent; the spans match for this |
| 679 | * so the property transfers. |
| 680 | */ |
| 681 | if (parent->flags & SD_PREFER_SIBLING) |
| 682 | tmp->flags |= SD_PREFER_SIBLING; |
| 683 | destroy_sched_domain(parent); |
| 684 | } else |
| 685 | tmp = tmp->parent; |
| 686 | } |
| 687 | |
| 688 | if (sd && sd_degenerate(sd)) { |
| 689 | tmp = sd; |
| 690 | sd = sd->parent; |
| 691 | destroy_sched_domain(tmp); |
| 692 | if (sd) |
| 693 | sd->child = NULL; |
| 694 | } |
| 695 | |
| 696 | sched_domain_debug(sd, cpu); |
| 697 | |
| 698 | rq_attach_root(rq, rd); |
| 699 | tmp = rq->sd; |
| 700 | rcu_assign_pointer(rq->sd, sd); |
Peter Zijlstra | bbdacdf | 2017-08-10 17:10:26 +0200 | [diff] [blame] | 701 | dirty_sched_domain_sysctl(cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 702 | destroy_sched_domains(tmp); |
| 703 | |
| 704 | update_top_cache_domain(cpu); |
| 705 | } |
| 706 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 707 | struct s_data { |
Luc Van Oostenryck | 99687cd | 2019-01-18 15:49:36 +0100 | [diff] [blame] | 708 | struct sched_domain * __percpu *sd; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 709 | struct root_domain *rd; |
| 710 | }; |
| 711 | |
| 712 | enum s_alloc { |
| 713 | sa_rootdomain, |
| 714 | sa_sd, |
| 715 | sa_sd_storage, |
| 716 | sa_none, |
| 717 | }; |
| 718 | |
| 719 | /* |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 720 | * Return the canonical balance CPU for this group, this is the first CPU |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 721 | * of this group that's also in the balance mask. |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 722 | * |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 723 | * The balance mask are all those CPUs that could actually end up at this |
| 724 | * group. See build_balance_mask(). |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 725 | * |
| 726 | * Also see should_we_balance(). |
| 727 | */ |
| 728 | int group_balance_cpu(struct sched_group *sg) |
| 729 | { |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 730 | return cpumask_first(group_balance_mask(sg)); |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 731 | } |
| 732 | |
| 733 | |
| 734 | /* |
| 735 | * NUMA topology (first read the regular topology blurb below) |
| 736 | * |
| 737 | * Given a node-distance table, for example: |
| 738 | * |
| 739 | * node 0 1 2 3 |
| 740 | * 0: 10 20 30 20 |
| 741 | * 1: 20 10 20 30 |
| 742 | * 2: 30 20 10 20 |
| 743 | * 3: 20 30 20 10 |
| 744 | * |
| 745 | * which represents a 4 node ring topology like: |
| 746 | * |
| 747 | * 0 ----- 1 |
| 748 | * | | |
| 749 | * | | |
| 750 | * | | |
| 751 | * 3 ----- 2 |
| 752 | * |
| 753 | * We want to construct domains and groups to represent this. The way we go |
| 754 | * about doing this is to build the domains on 'hops'. For each NUMA level we |
| 755 | * construct the mask of all nodes reachable in @level hops. |
| 756 | * |
| 757 | * For the above NUMA topology that gives 3 levels: |
| 758 | * |
| 759 | * NUMA-2 0-3 0-3 0-3 0-3 |
| 760 | * groups: {0-1,3},{1-3} {0-2},{0,2-3} {1-3},{0-1,3} {0,2-3},{0-2} |
| 761 | * |
| 762 | * NUMA-1 0-1,3 0-2 1-3 0,2-3 |
| 763 | * groups: {0},{1},{3} {0},{1},{2} {1},{2},{3} {0},{2},{3} |
| 764 | * |
| 765 | * NUMA-0 0 1 2 3 |
| 766 | * |
| 767 | * |
| 768 | * As can be seen; things don't nicely line up as with the regular topology. |
| 769 | * When we iterate a domain in child domain chunks some nodes can be |
| 770 | * represented multiple times -- hence the "overlap" naming for this part of |
| 771 | * the topology. |
| 772 | * |
| 773 | * In order to minimize this overlap, we only build enough groups to cover the |
| 774 | * domain. For instance Node-0 NUMA-2 would only get groups: 0-1,3 and 1-3. |
| 775 | * |
| 776 | * Because: |
| 777 | * |
| 778 | * - the first group of each domain is its child domain; this |
| 779 | * gets us the first 0-1,3 |
| 780 | * - the only uncovered node is 2, who's child domain is 1-3. |
| 781 | * |
| 782 | * However, because of the overlap, computing a unique CPU for each group is |
| 783 | * more complicated. Consider for instance the groups of NODE-1 NUMA-2, both |
| 784 | * groups include the CPUs of Node-0, while those CPUs would not in fact ever |
| 785 | * end up at those groups (they would end up in group: 0-1,3). |
| 786 | * |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 787 | * To correct this we have to introduce the group balance mask. This mask |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 788 | * will contain those CPUs in the group that can reach this group given the |
| 789 | * (child) domain tree. |
| 790 | * |
| 791 | * With this we can once again compute balance_cpu and sched_group_capacity |
| 792 | * relations. |
| 793 | * |
| 794 | * XXX include words on how balance_cpu is unique and therefore can be |
| 795 | * used for sched_group_capacity links. |
| 796 | * |
| 797 | * |
| 798 | * Another 'interesting' topology is: |
| 799 | * |
| 800 | * node 0 1 2 3 |
| 801 | * 0: 10 20 20 30 |
| 802 | * 1: 20 10 20 20 |
| 803 | * 2: 20 20 10 20 |
| 804 | * 3: 30 20 20 10 |
| 805 | * |
| 806 | * Which looks a little like: |
| 807 | * |
| 808 | * 0 ----- 1 |
| 809 | * | / | |
| 810 | * | / | |
| 811 | * | / | |
| 812 | * 2 ----- 3 |
| 813 | * |
| 814 | * This topology is asymmetric, nodes 1,2 are fully connected, but nodes 0,3 |
| 815 | * are not. |
| 816 | * |
| 817 | * This leads to a few particularly weird cases where the sched_domain's are |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 818 | * not of the same number for each CPU. Consider: |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 819 | * |
| 820 | * NUMA-2 0-3 0-3 |
| 821 | * groups: {0-2},{1-3} {1-3},{0-2} |
| 822 | * |
| 823 | * NUMA-1 0-2 0-3 0-3 1-3 |
| 824 | * |
| 825 | * NUMA-0 0 1 2 3 |
| 826 | * |
| 827 | */ |
| 828 | |
| 829 | |
| 830 | /* |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 831 | * Build the balance mask; it contains only those CPUs that can arrive at this |
| 832 | * group and should be considered to continue balancing. |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 833 | * |
| 834 | * We do this during the group creation pass, therefore the group information |
| 835 | * isn't complete yet, however since each group represents a (child) domain we |
| 836 | * can fully construct this using the sched_domain bits (which are already |
| 837 | * complete). |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 838 | */ |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 839 | static void |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 840 | build_balance_mask(struct sched_domain *sd, struct sched_group *sg, struct cpumask *mask) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 841 | { |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 842 | const struct cpumask *sg_span = sched_group_span(sg); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 843 | struct sd_data *sdd = sd->private; |
| 844 | struct sched_domain *sibling; |
| 845 | int i; |
| 846 | |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 847 | cpumask_clear(mask); |
| 848 | |
Lauro Ramos Venancio | f32d782 | 2017-04-20 16:51:40 -0300 | [diff] [blame] | 849 | for_each_cpu(i, sg_span) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 850 | sibling = *per_cpu_ptr(sdd->sd, i); |
Peter Zijlstra | 73bb059 | 2017-04-25 14:00:49 +0200 | [diff] [blame] | 851 | |
| 852 | /* |
| 853 | * Can happen in the asymmetric case, where these siblings are |
| 854 | * unused. The mask will not be empty because those CPUs that |
| 855 | * do have the top domain _should_ span the domain. |
| 856 | */ |
| 857 | if (!sibling->child) |
| 858 | continue; |
| 859 | |
| 860 | /* If we would not end up here, we can't continue from here */ |
| 861 | if (!cpumask_equal(sg_span, sched_domain_span(sibling->child))) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 862 | continue; |
| 863 | |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 864 | cpumask_set_cpu(i, mask); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 865 | } |
Peter Zijlstra | 73bb059 | 2017-04-25 14:00:49 +0200 | [diff] [blame] | 866 | |
| 867 | /* We must not have empty masks here */ |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 868 | WARN_ON_ONCE(cpumask_empty(mask)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 869 | } |
| 870 | |
| 871 | /* |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 872 | * XXX: This creates per-node group entries; since the load-balancer will |
| 873 | * immediately access remote memory to construct this group's load-balance |
| 874 | * statistics having the groups node local is of dubious benefit. |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 875 | */ |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 876 | static struct sched_group * |
| 877 | build_group_from_child_sched_domain(struct sched_domain *sd, int cpu) |
| 878 | { |
| 879 | struct sched_group *sg; |
| 880 | struct cpumask *sg_span; |
| 881 | |
| 882 | sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), |
| 883 | GFP_KERNEL, cpu_to_node(cpu)); |
| 884 | |
| 885 | if (!sg) |
| 886 | return NULL; |
| 887 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 888 | sg_span = sched_group_span(sg); |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 889 | if (sd->child) |
| 890 | cpumask_copy(sg_span, sched_domain_span(sd->child)); |
| 891 | else |
| 892 | cpumask_copy(sg_span, sched_domain_span(sd)); |
| 893 | |
Shu Wang | 213c5a4 | 2017-08-10 15:52:16 +0800 | [diff] [blame] | 894 | atomic_inc(&sg->ref); |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 895 | return sg; |
| 896 | } |
| 897 | |
| 898 | static void init_overlap_sched_group(struct sched_domain *sd, |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 899 | struct sched_group *sg) |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 900 | { |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 901 | struct cpumask *mask = sched_domains_tmpmask2; |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 902 | struct sd_data *sdd = sd->private; |
| 903 | struct cpumask *sg_span; |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 904 | int cpu; |
| 905 | |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 906 | build_balance_mask(sd, sg, mask); |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 907 | cpu = cpumask_first_and(sched_group_span(sg), mask); |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 908 | |
| 909 | sg->sgc = *per_cpu_ptr(sdd->sgc, cpu); |
| 910 | if (atomic_inc_return(&sg->sgc->ref) == 1) |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 911 | cpumask_copy(group_balance_mask(sg), mask); |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 912 | else |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 913 | WARN_ON_ONCE(!cpumask_equal(group_balance_mask(sg), mask)); |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 914 | |
| 915 | /* |
| 916 | * Initialize sgc->capacity such that even if we mess up the |
| 917 | * domains and no possible iteration will get us here, we won't |
| 918 | * die on a /0 trap. |
| 919 | */ |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 920 | sg_span = sched_group_span(sg); |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 921 | sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span); |
| 922 | sg->sgc->min_capacity = SCHED_CAPACITY_SCALE; |
Morten Rasmussen | e3d6d0c | 2018-07-04 11:17:41 +0100 | [diff] [blame] | 923 | sg->sgc->max_capacity = SCHED_CAPACITY_SCALE; |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 924 | } |
| 925 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 926 | static int |
| 927 | build_overlap_sched_groups(struct sched_domain *sd, int cpu) |
| 928 | { |
Peter Zijlstra | 91eaed0 | 2017-04-14 17:32:07 +0200 | [diff] [blame] | 929 | struct sched_group *first = NULL, *last = NULL, *sg; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 930 | const struct cpumask *span = sched_domain_span(sd); |
| 931 | struct cpumask *covered = sched_domains_tmpmask; |
| 932 | struct sd_data *sdd = sd->private; |
| 933 | struct sched_domain *sibling; |
| 934 | int i; |
| 935 | |
| 936 | cpumask_clear(covered); |
| 937 | |
Peter Zijlstra | 0372dd2 | 2017-04-14 17:24:02 +0200 | [diff] [blame] | 938 | for_each_cpu_wrap(i, span, cpu) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 939 | struct cpumask *sg_span; |
| 940 | |
| 941 | if (cpumask_test_cpu(i, covered)) |
| 942 | continue; |
| 943 | |
| 944 | sibling = *per_cpu_ptr(sdd->sd, i); |
| 945 | |
Lauro Ramos Venancio | c20e1ea | 2017-04-20 16:51:42 -0300 | [diff] [blame] | 946 | /* |
| 947 | * Asymmetric node setups can result in situations where the |
| 948 | * domain tree is of unequal depth, make sure to skip domains |
| 949 | * that already cover the entire range. |
| 950 | * |
| 951 | * In that case build_sched_domains() will have terminated the |
| 952 | * iteration early and our sibling sd spans will be empty. |
| 953 | * Domains should always include the CPU they're built on, so |
| 954 | * check that. |
| 955 | */ |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 956 | if (!cpumask_test_cpu(i, sched_domain_span(sibling))) |
| 957 | continue; |
| 958 | |
Lauro Ramos Venancio | 8c03346 | 2017-04-13 10:56:07 -0300 | [diff] [blame] | 959 | sg = build_group_from_child_sched_domain(sibling, cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 960 | if (!sg) |
| 961 | goto fail; |
| 962 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 963 | sg_span = sched_group_span(sg); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 964 | cpumask_or(covered, covered, sg_span); |
| 965 | |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 966 | init_overlap_sched_group(sd, sg); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 967 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 968 | if (!first) |
| 969 | first = sg; |
| 970 | if (last) |
| 971 | last->next = sg; |
| 972 | last = sg; |
| 973 | last->next = first; |
| 974 | } |
Peter Zijlstra | 91eaed0 | 2017-04-14 17:32:07 +0200 | [diff] [blame] | 975 | sd->groups = first; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 976 | |
| 977 | return 0; |
| 978 | |
| 979 | fail: |
| 980 | free_sched_groups(first, 0); |
| 981 | |
| 982 | return -ENOMEM; |
| 983 | } |
| 984 | |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 985 | |
| 986 | /* |
| 987 | * Package topology (also see the load-balance blurb in fair.c) |
| 988 | * |
| 989 | * The scheduler builds a tree structure to represent a number of important |
| 990 | * topology features. By default (default_topology[]) these include: |
| 991 | * |
| 992 | * - Simultaneous multithreading (SMT) |
| 993 | * - Multi-Core Cache (MC) |
| 994 | * - Package (DIE) |
| 995 | * |
| 996 | * Where the last one more or less denotes everything up to a NUMA node. |
| 997 | * |
| 998 | * The tree consists of 3 primary data structures: |
| 999 | * |
| 1000 | * sched_domain -> sched_group -> sched_group_capacity |
| 1001 | * ^ ^ ^ ^ |
| 1002 | * `-' `-' |
| 1003 | * |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 1004 | * The sched_domains are per-CPU and have a two way link (parent & child) and |
Peter Zijlstra | 35a566e | 2017-04-28 10:54:26 +0200 | [diff] [blame] | 1005 | * denote the ever growing mask of CPUs belonging to that level of topology. |
| 1006 | * |
| 1007 | * Each sched_domain has a circular (double) linked list of sched_group's, each |
| 1008 | * denoting the domains of the level below (or individual CPUs in case of the |
| 1009 | * first domain level). The sched_group linked by a sched_domain includes the |
| 1010 | * CPU of that sched_domain [*]. |
| 1011 | * |
| 1012 | * Take for instance a 2 threaded, 2 core, 2 cache cluster part: |
| 1013 | * |
| 1014 | * CPU 0 1 2 3 4 5 6 7 |
| 1015 | * |
| 1016 | * DIE [ ] |
| 1017 | * MC [ ] [ ] |
| 1018 | * SMT [ ] [ ] [ ] [ ] |
| 1019 | * |
| 1020 | * - or - |
| 1021 | * |
| 1022 | * DIE 0-7 0-7 0-7 0-7 0-7 0-7 0-7 0-7 |
| 1023 | * MC 0-3 0-3 0-3 0-3 4-7 4-7 4-7 4-7 |
| 1024 | * SMT 0-1 0-1 2-3 2-3 4-5 4-5 6-7 6-7 |
| 1025 | * |
| 1026 | * CPU 0 1 2 3 4 5 6 7 |
| 1027 | * |
| 1028 | * One way to think about it is: sched_domain moves you up and down among these |
| 1029 | * topology levels, while sched_group moves you sideways through it, at child |
| 1030 | * domain granularity. |
| 1031 | * |
| 1032 | * sched_group_capacity ensures each unique sched_group has shared storage. |
| 1033 | * |
| 1034 | * There are two related construction problems, both require a CPU that |
| 1035 | * uniquely identify each group (for a given domain): |
| 1036 | * |
| 1037 | * - The first is the balance_cpu (see should_we_balance() and the |
| 1038 | * load-balance blub in fair.c); for each group we only want 1 CPU to |
| 1039 | * continue balancing at a higher domain. |
| 1040 | * |
| 1041 | * - The second is the sched_group_capacity; we want all identical groups |
| 1042 | * to share a single sched_group_capacity. |
| 1043 | * |
| 1044 | * Since these topologies are exclusive by construction. That is, its |
| 1045 | * impossible for an SMT thread to belong to multiple cores, and cores to |
| 1046 | * be part of multiple caches. There is a very clear and unique location |
| 1047 | * for each CPU in the hierarchy. |
| 1048 | * |
| 1049 | * Therefore computing a unique CPU for each group is trivial (the iteration |
| 1050 | * mask is redundant and set all 1s; all CPUs in a group will end up at _that_ |
| 1051 | * group), we can simply pick the first CPU in each group. |
| 1052 | * |
| 1053 | * |
| 1054 | * [*] in other words, the first group of each domain is its child domain. |
| 1055 | */ |
| 1056 | |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1057 | static struct sched_group *get_group(int cpu, struct sd_data *sdd) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1058 | { |
| 1059 | struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu); |
| 1060 | struct sched_domain *child = sd->child; |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1061 | struct sched_group *sg; |
Valentin Schneider | 67d4f6f | 2019-04-09 18:35:45 +0100 | [diff] [blame] | 1062 | bool already_visited; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1063 | |
| 1064 | if (child) |
| 1065 | cpu = cpumask_first(sched_domain_span(child)); |
| 1066 | |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1067 | sg = *per_cpu_ptr(sdd->sg, cpu); |
| 1068 | sg->sgc = *per_cpu_ptr(sdd->sgc, cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1069 | |
Valentin Schneider | 67d4f6f | 2019-04-09 18:35:45 +0100 | [diff] [blame] | 1070 | /* Increase refcounts for claim_allocations: */ |
| 1071 | already_visited = atomic_inc_return(&sg->ref) > 1; |
| 1072 | /* sgc visits should follow a similar trend as sg */ |
| 1073 | WARN_ON(already_visited != (atomic_inc_return(&sg->sgc->ref) > 1)); |
| 1074 | |
| 1075 | /* If we have already visited that group, it's already initialized. */ |
| 1076 | if (already_visited) |
| 1077 | return sg; |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1078 | |
| 1079 | if (child) { |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 1080 | cpumask_copy(sched_group_span(sg), sched_domain_span(child)); |
| 1081 | cpumask_copy(group_balance_mask(sg), sched_group_span(sg)); |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1082 | } else { |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 1083 | cpumask_set_cpu(cpu, sched_group_span(sg)); |
Peter Zijlstra | e5c14b1 | 2017-05-01 10:47:02 +0200 | [diff] [blame] | 1084 | cpumask_set_cpu(cpu, group_balance_mask(sg)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1085 | } |
| 1086 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 1087 | sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sched_group_span(sg)); |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1088 | sg->sgc->min_capacity = SCHED_CAPACITY_SCALE; |
Morten Rasmussen | e3d6d0c | 2018-07-04 11:17:41 +0100 | [diff] [blame] | 1089 | sg->sgc->max_capacity = SCHED_CAPACITY_SCALE; |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1090 | |
| 1091 | return sg; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1092 | } |
| 1093 | |
| 1094 | /* |
| 1095 | * build_sched_groups will build a circular linked list of the groups |
Valentin Schneider | d874323 | 2019-04-09 18:35:46 +0100 | [diff] [blame] | 1096 | * covered by the given span, will set each group's ->cpumask correctly, |
| 1097 | * and will initialize their ->sgc. |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1098 | * |
| 1099 | * Assumes the sched_domain tree is fully constructed |
| 1100 | */ |
| 1101 | static int |
| 1102 | build_sched_groups(struct sched_domain *sd, int cpu) |
| 1103 | { |
| 1104 | struct sched_group *first = NULL, *last = NULL; |
| 1105 | struct sd_data *sdd = sd->private; |
| 1106 | const struct cpumask *span = sched_domain_span(sd); |
| 1107 | struct cpumask *covered; |
| 1108 | int i; |
| 1109 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1110 | lockdep_assert_held(&sched_domains_mutex); |
| 1111 | covered = sched_domains_tmpmask; |
| 1112 | |
| 1113 | cpumask_clear(covered); |
| 1114 | |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1115 | for_each_cpu_wrap(i, span, cpu) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1116 | struct sched_group *sg; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1117 | |
| 1118 | if (cpumask_test_cpu(i, covered)) |
| 1119 | continue; |
| 1120 | |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1121 | sg = get_group(i, sdd); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1122 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 1123 | cpumask_or(covered, covered, sched_group_span(sg)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1124 | |
| 1125 | if (!first) |
| 1126 | first = sg; |
| 1127 | if (last) |
| 1128 | last->next = sg; |
| 1129 | last = sg; |
| 1130 | } |
| 1131 | last->next = first; |
Peter Zijlstra | 0c0e776 | 2017-05-03 14:18:06 +0200 | [diff] [blame] | 1132 | sd->groups = first; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1133 | |
| 1134 | return 0; |
| 1135 | } |
| 1136 | |
| 1137 | /* |
| 1138 | * Initialize sched groups cpu_capacity. |
| 1139 | * |
| 1140 | * cpu_capacity indicates the capacity of sched group, which is used while |
| 1141 | * distributing the load between different sched groups in a sched domain. |
| 1142 | * Typically cpu_capacity for all the groups in a sched domain will be same |
| 1143 | * unless there are asymmetries in the topology. If there are asymmetries, |
| 1144 | * group having more cpu_capacity will pickup more load compared to the |
| 1145 | * group having less cpu_capacity. |
| 1146 | */ |
| 1147 | static void init_sched_groups_capacity(int cpu, struct sched_domain *sd) |
| 1148 | { |
| 1149 | struct sched_group *sg = sd->groups; |
| 1150 | |
| 1151 | WARN_ON(!sg); |
| 1152 | |
| 1153 | do { |
| 1154 | int cpu, max_cpu = -1; |
| 1155 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 1156 | sg->group_weight = cpumask_weight(sched_group_span(sg)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1157 | |
| 1158 | if (!(sd->flags & SD_ASYM_PACKING)) |
| 1159 | goto next; |
| 1160 | |
Peter Zijlstra | ae4df9d | 2017-05-01 11:03:12 +0200 | [diff] [blame] | 1161 | for_each_cpu(cpu, sched_group_span(sg)) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1162 | if (max_cpu < 0) |
| 1163 | max_cpu = cpu; |
| 1164 | else if (sched_asym_prefer(cpu, max_cpu)) |
| 1165 | max_cpu = cpu; |
| 1166 | } |
| 1167 | sg->asym_prefer_cpu = max_cpu; |
| 1168 | |
| 1169 | next: |
| 1170 | sg = sg->next; |
| 1171 | } while (sg != sd->groups); |
| 1172 | |
| 1173 | if (cpu != group_balance_cpu(sg)) |
| 1174 | return; |
| 1175 | |
| 1176 | update_group_capacity(sd, cpu); |
| 1177 | } |
| 1178 | |
| 1179 | /* |
| 1180 | * Initializers for schedule domains |
| 1181 | * Non-inlined to reduce accumulated stack pressure in build_sched_domains() |
| 1182 | */ |
| 1183 | |
| 1184 | static int default_relax_domain_level = -1; |
| 1185 | int sched_domain_level_max; |
| 1186 | |
| 1187 | static int __init setup_relax_domain_level(char *str) |
| 1188 | { |
| 1189 | if (kstrtoint(str, 0, &default_relax_domain_level)) |
| 1190 | pr_warn("Unable to set relax_domain_level\n"); |
| 1191 | |
| 1192 | return 1; |
| 1193 | } |
| 1194 | __setup("relax_domain_level=", setup_relax_domain_level); |
| 1195 | |
| 1196 | static void set_domain_attribute(struct sched_domain *sd, |
| 1197 | struct sched_domain_attr *attr) |
| 1198 | { |
| 1199 | int request; |
| 1200 | |
| 1201 | if (!attr || attr->relax_domain_level < 0) { |
| 1202 | if (default_relax_domain_level < 0) |
| 1203 | return; |
| 1204 | else |
| 1205 | request = default_relax_domain_level; |
| 1206 | } else |
| 1207 | request = attr->relax_domain_level; |
| 1208 | if (request < sd->level) { |
| 1209 | /* Turn off idle balance on this domain: */ |
| 1210 | sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); |
| 1211 | } else { |
| 1212 | /* Turn on idle balance on this domain: */ |
| 1213 | sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); |
| 1214 | } |
| 1215 | } |
| 1216 | |
| 1217 | static void __sdt_free(const struct cpumask *cpu_map); |
| 1218 | static int __sdt_alloc(const struct cpumask *cpu_map); |
| 1219 | |
| 1220 | static void __free_domain_allocs(struct s_data *d, enum s_alloc what, |
| 1221 | const struct cpumask *cpu_map) |
| 1222 | { |
| 1223 | switch (what) { |
| 1224 | case sa_rootdomain: |
| 1225 | if (!atomic_read(&d->rd->refcount)) |
| 1226 | free_rootdomain(&d->rd->rcu); |
| 1227 | /* Fall through */ |
| 1228 | case sa_sd: |
| 1229 | free_percpu(d->sd); |
| 1230 | /* Fall through */ |
| 1231 | case sa_sd_storage: |
| 1232 | __sdt_free(cpu_map); |
| 1233 | /* Fall through */ |
| 1234 | case sa_none: |
| 1235 | break; |
| 1236 | } |
| 1237 | } |
| 1238 | |
| 1239 | static enum s_alloc |
| 1240 | __visit_domain_allocation_hell(struct s_data *d, const struct cpumask *cpu_map) |
| 1241 | { |
| 1242 | memset(d, 0, sizeof(*d)); |
| 1243 | |
| 1244 | if (__sdt_alloc(cpu_map)) |
| 1245 | return sa_sd_storage; |
| 1246 | d->sd = alloc_percpu(struct sched_domain *); |
| 1247 | if (!d->sd) |
| 1248 | return sa_sd_storage; |
| 1249 | d->rd = alloc_rootdomain(); |
| 1250 | if (!d->rd) |
| 1251 | return sa_sd; |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 1252 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1253 | return sa_rootdomain; |
| 1254 | } |
| 1255 | |
| 1256 | /* |
| 1257 | * NULL the sd_data elements we've used to build the sched_domain and |
| 1258 | * sched_group structure so that the subsequent __free_domain_allocs() |
| 1259 | * will not free the data we're using. |
| 1260 | */ |
| 1261 | static void claim_allocations(int cpu, struct sched_domain *sd) |
| 1262 | { |
| 1263 | struct sd_data *sdd = sd->private; |
| 1264 | |
| 1265 | WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd); |
| 1266 | *per_cpu_ptr(sdd->sd, cpu) = NULL; |
| 1267 | |
| 1268 | if (atomic_read(&(*per_cpu_ptr(sdd->sds, cpu))->ref)) |
| 1269 | *per_cpu_ptr(sdd->sds, cpu) = NULL; |
| 1270 | |
| 1271 | if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref)) |
| 1272 | *per_cpu_ptr(sdd->sg, cpu) = NULL; |
| 1273 | |
| 1274 | if (atomic_read(&(*per_cpu_ptr(sdd->sgc, cpu))->ref)) |
| 1275 | *per_cpu_ptr(sdd->sgc, cpu) = NULL; |
| 1276 | } |
| 1277 | |
| 1278 | #ifdef CONFIG_NUMA |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1279 | enum numa_topology_type sched_numa_topology_type; |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 1280 | |
| 1281 | static int sched_domains_numa_levels; |
| 1282 | static int sched_domains_curr_level; |
| 1283 | |
| 1284 | int sched_max_numa_distance; |
| 1285 | static int *sched_domains_numa_distance; |
| 1286 | static struct cpumask ***sched_domains_numa_masks; |
Matt Fleming | a55c745 | 2019-08-08 20:53:01 +0100 | [diff] [blame] | 1287 | int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1288 | #endif |
| 1289 | |
| 1290 | /* |
| 1291 | * SD_flags allowed in topology descriptions. |
| 1292 | * |
| 1293 | * These flags are purely descriptive of the topology and do not prescribe |
| 1294 | * behaviour. Behaviour is artificial and mapped in the below sd_init() |
| 1295 | * function: |
| 1296 | * |
| 1297 | * SD_SHARE_CPUCAPACITY - describes SMT topologies |
| 1298 | * SD_SHARE_PKG_RESOURCES - describes shared caches |
| 1299 | * SD_NUMA - describes NUMA topologies |
| 1300 | * SD_SHARE_POWERDOMAIN - describes shared power domain |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1301 | * |
| 1302 | * Odd one out, which beside describing the topology has a quirk also |
| 1303 | * prescribes the desired behaviour that goes along with it: |
| 1304 | * |
| 1305 | * SD_ASYM_PACKING - describes SMT quirks |
| 1306 | */ |
| 1307 | #define TOPOLOGY_SD_FLAGS \ |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 1308 | (SD_SHARE_CPUCAPACITY | \ |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1309 | SD_SHARE_PKG_RESOURCES | \ |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 1310 | SD_NUMA | \ |
| 1311 | SD_ASYM_PACKING | \ |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1312 | SD_SHARE_POWERDOMAIN) |
| 1313 | |
| 1314 | static struct sched_domain * |
| 1315 | sd_init(struct sched_domain_topology_level *tl, |
| 1316 | const struct cpumask *cpu_map, |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1317 | struct sched_domain *child, int dflags, int cpu) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1318 | { |
| 1319 | struct sd_data *sdd = &tl->data; |
| 1320 | struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu); |
| 1321 | int sd_id, sd_weight, sd_flags = 0; |
| 1322 | |
| 1323 | #ifdef CONFIG_NUMA |
| 1324 | /* |
| 1325 | * Ugly hack to pass state to sd_numa_mask()... |
| 1326 | */ |
| 1327 | sched_domains_curr_level = tl->numa_level; |
| 1328 | #endif |
| 1329 | |
| 1330 | sd_weight = cpumask_weight(tl->mask(cpu)); |
| 1331 | |
| 1332 | if (tl->sd_flags) |
| 1333 | sd_flags = (*tl->sd_flags)(); |
| 1334 | if (WARN_ONCE(sd_flags & ~TOPOLOGY_SD_FLAGS, |
| 1335 | "wrong sd_flags in topology description\n")) |
| 1336 | sd_flags &= ~TOPOLOGY_SD_FLAGS; |
| 1337 | |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1338 | /* Apply detected topology flags */ |
| 1339 | sd_flags |= dflags; |
| 1340 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1341 | *sd = (struct sched_domain){ |
| 1342 | .min_interval = sd_weight, |
| 1343 | .max_interval = 2*sd_weight, |
| 1344 | .busy_factor = 32, |
| 1345 | .imbalance_pct = 125, |
| 1346 | |
| 1347 | .cache_nice_tries = 0, |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1348 | |
| 1349 | .flags = 1*SD_LOAD_BALANCE |
| 1350 | | 1*SD_BALANCE_NEWIDLE |
| 1351 | | 1*SD_BALANCE_EXEC |
| 1352 | | 1*SD_BALANCE_FORK |
| 1353 | | 0*SD_BALANCE_WAKE |
| 1354 | | 1*SD_WAKE_AFFINE |
| 1355 | | 0*SD_SHARE_CPUCAPACITY |
| 1356 | | 0*SD_SHARE_PKG_RESOURCES |
| 1357 | | 0*SD_SERIALIZE |
Morten Rasmussen | 9c63e84 | 2018-07-04 11:17:50 +0100 | [diff] [blame] | 1358 | | 1*SD_PREFER_SIBLING |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1359 | | 0*SD_NUMA |
| 1360 | | sd_flags |
| 1361 | , |
| 1362 | |
| 1363 | .last_balance = jiffies, |
| 1364 | .balance_interval = sd_weight, |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1365 | .max_newidle_lb_cost = 0, |
| 1366 | .next_decay_max_lb_cost = jiffies, |
| 1367 | .child = child, |
| 1368 | #ifdef CONFIG_SCHED_DEBUG |
| 1369 | .name = tl->name, |
| 1370 | #endif |
| 1371 | }; |
| 1372 | |
| 1373 | cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); |
| 1374 | sd_id = cpumask_first(sched_domain_span(sd)); |
| 1375 | |
| 1376 | /* |
| 1377 | * Convert topological properties into behaviour. |
| 1378 | */ |
| 1379 | |
| 1380 | if (sd->flags & SD_ASYM_CPUCAPACITY) { |
| 1381 | struct sched_domain *t = sd; |
| 1382 | |
Morten Rasmussen | 9c63e84 | 2018-07-04 11:17:50 +0100 | [diff] [blame] | 1383 | /* |
| 1384 | * Don't attempt to spread across CPUs of different capacities. |
| 1385 | */ |
| 1386 | if (sd->child) |
| 1387 | sd->child->flags &= ~SD_PREFER_SIBLING; |
| 1388 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1389 | for_each_lower_domain(t) |
| 1390 | t->flags |= SD_BALANCE_WAKE; |
| 1391 | } |
| 1392 | |
| 1393 | if (sd->flags & SD_SHARE_CPUCAPACITY) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1394 | sd->imbalance_pct = 110; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1395 | |
| 1396 | } else if (sd->flags & SD_SHARE_PKG_RESOURCES) { |
| 1397 | sd->imbalance_pct = 117; |
| 1398 | sd->cache_nice_tries = 1; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1399 | |
| 1400 | #ifdef CONFIG_NUMA |
| 1401 | } else if (sd->flags & SD_NUMA) { |
| 1402 | sd->cache_nice_tries = 2; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1403 | |
Morten Rasmussen | 9c63e84 | 2018-07-04 11:17:50 +0100 | [diff] [blame] | 1404 | sd->flags &= ~SD_PREFER_SIBLING; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1405 | sd->flags |= SD_SERIALIZE; |
Matt Fleming | a55c745 | 2019-08-08 20:53:01 +0100 | [diff] [blame] | 1406 | if (sched_domains_numa_distance[tl->numa_level] > node_reclaim_distance) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1407 | sd->flags &= ~(SD_BALANCE_EXEC | |
| 1408 | SD_BALANCE_FORK | |
| 1409 | SD_WAKE_AFFINE); |
| 1410 | } |
| 1411 | |
| 1412 | #endif |
| 1413 | } else { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1414 | sd->cache_nice_tries = 1; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1415 | } |
| 1416 | |
| 1417 | /* |
| 1418 | * For all levels sharing cache; connect a sched_domain_shared |
| 1419 | * instance. |
| 1420 | */ |
| 1421 | if (sd->flags & SD_SHARE_PKG_RESOURCES) { |
| 1422 | sd->shared = *per_cpu_ptr(sdd->sds, sd_id); |
| 1423 | atomic_inc(&sd->shared->ref); |
| 1424 | atomic_set(&sd->shared->nr_busy_cpus, sd_weight); |
| 1425 | } |
| 1426 | |
| 1427 | sd->private = sdd; |
| 1428 | |
| 1429 | return sd; |
| 1430 | } |
| 1431 | |
| 1432 | /* |
| 1433 | * Topology list, bottom-up. |
| 1434 | */ |
| 1435 | static struct sched_domain_topology_level default_topology[] = { |
| 1436 | #ifdef CONFIG_SCHED_SMT |
| 1437 | { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) }, |
| 1438 | #endif |
| 1439 | #ifdef CONFIG_SCHED_MC |
| 1440 | { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) }, |
| 1441 | #endif |
| 1442 | { cpu_cpu_mask, SD_INIT_NAME(DIE) }, |
| 1443 | { NULL, }, |
| 1444 | }; |
| 1445 | |
| 1446 | static struct sched_domain_topology_level *sched_domain_topology = |
| 1447 | default_topology; |
| 1448 | |
| 1449 | #define for_each_sd_topology(tl) \ |
| 1450 | for (tl = sched_domain_topology; tl->mask; tl++) |
| 1451 | |
| 1452 | void set_sched_topology(struct sched_domain_topology_level *tl) |
| 1453 | { |
| 1454 | if (WARN_ON_ONCE(sched_smp_initialized)) |
| 1455 | return; |
| 1456 | |
| 1457 | sched_domain_topology = tl; |
| 1458 | } |
| 1459 | |
| 1460 | #ifdef CONFIG_NUMA |
| 1461 | |
| 1462 | static const struct cpumask *sd_numa_mask(int cpu) |
| 1463 | { |
| 1464 | return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)]; |
| 1465 | } |
| 1466 | |
| 1467 | static void sched_numa_warn(const char *str) |
| 1468 | { |
| 1469 | static int done = false; |
| 1470 | int i,j; |
| 1471 | |
| 1472 | if (done) |
| 1473 | return; |
| 1474 | |
| 1475 | done = true; |
| 1476 | |
| 1477 | printk(KERN_WARNING "ERROR: %s\n\n", str); |
| 1478 | |
| 1479 | for (i = 0; i < nr_node_ids; i++) { |
| 1480 | printk(KERN_WARNING " "); |
| 1481 | for (j = 0; j < nr_node_ids; j++) |
| 1482 | printk(KERN_CONT "%02d ", node_distance(i,j)); |
| 1483 | printk(KERN_CONT "\n"); |
| 1484 | } |
| 1485 | printk(KERN_WARNING "\n"); |
| 1486 | } |
| 1487 | |
| 1488 | bool find_numa_distance(int distance) |
| 1489 | { |
| 1490 | int i; |
| 1491 | |
| 1492 | if (distance == node_distance(0, 0)) |
| 1493 | return true; |
| 1494 | |
| 1495 | for (i = 0; i < sched_domains_numa_levels; i++) { |
| 1496 | if (sched_domains_numa_distance[i] == distance) |
| 1497 | return true; |
| 1498 | } |
| 1499 | |
| 1500 | return false; |
| 1501 | } |
| 1502 | |
| 1503 | /* |
| 1504 | * A system can have three types of NUMA topology: |
| 1505 | * NUMA_DIRECT: all nodes are directly connected, or not a NUMA system |
| 1506 | * NUMA_GLUELESS_MESH: some nodes reachable through intermediary nodes |
| 1507 | * NUMA_BACKPLANE: nodes can reach other nodes through a backplane |
| 1508 | * |
| 1509 | * The difference between a glueless mesh topology and a backplane |
| 1510 | * topology lies in whether communication between not directly |
| 1511 | * connected nodes goes through intermediary nodes (where programs |
| 1512 | * could run), or through backplane controllers. This affects |
| 1513 | * placement of programs. |
| 1514 | * |
| 1515 | * The type of topology can be discerned with the following tests: |
| 1516 | * - If the maximum distance between any nodes is 1 hop, the system |
| 1517 | * is directly connected. |
| 1518 | * - If for two nodes A and B, located N > 1 hops away from each other, |
| 1519 | * there is an intermediary node C, which is < N hops away from both |
| 1520 | * nodes A and B, the system is a glueless mesh. |
| 1521 | */ |
| 1522 | static void init_numa_topology_type(void) |
| 1523 | { |
| 1524 | int a, b, c, n; |
| 1525 | |
| 1526 | n = sched_max_numa_distance; |
| 1527 | |
Srikar Dronamraju | e5e96fa | 2018-08-10 22:30:18 +0530 | [diff] [blame] | 1528 | if (sched_domains_numa_levels <= 2) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1529 | sched_numa_topology_type = NUMA_DIRECT; |
| 1530 | return; |
| 1531 | } |
| 1532 | |
| 1533 | for_each_online_node(a) { |
| 1534 | for_each_online_node(b) { |
| 1535 | /* Find two nodes furthest removed from each other. */ |
| 1536 | if (node_distance(a, b) < n) |
| 1537 | continue; |
| 1538 | |
| 1539 | /* Is there an intermediary node between a and b? */ |
| 1540 | for_each_online_node(c) { |
| 1541 | if (node_distance(a, c) < n && |
| 1542 | node_distance(b, c) < n) { |
| 1543 | sched_numa_topology_type = |
| 1544 | NUMA_GLUELESS_MESH; |
| 1545 | return; |
| 1546 | } |
| 1547 | } |
| 1548 | |
| 1549 | sched_numa_topology_type = NUMA_BACKPLANE; |
| 1550 | return; |
| 1551 | } |
| 1552 | } |
| 1553 | } |
| 1554 | |
| 1555 | void sched_init_numa(void) |
| 1556 | { |
| 1557 | int next_distance, curr_distance = node_distance(0, 0); |
| 1558 | struct sched_domain_topology_level *tl; |
| 1559 | int level = 0; |
| 1560 | int i, j, k; |
| 1561 | |
Peter Zijlstra | 993f0b0 | 2018-11-02 14:22:25 +0100 | [diff] [blame] | 1562 | sched_domains_numa_distance = kzalloc(sizeof(int) * (nr_node_ids + 1), GFP_KERNEL); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1563 | if (!sched_domains_numa_distance) |
| 1564 | return; |
| 1565 | |
Suravee Suthikulpanit | 051f3ca | 2017-09-07 02:20:05 -0500 | [diff] [blame] | 1566 | /* Includes NUMA identity node at level 0. */ |
| 1567 | sched_domains_numa_distance[level++] = curr_distance; |
| 1568 | sched_domains_numa_levels = level; |
| 1569 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1570 | /* |
| 1571 | * O(nr_nodes^2) deduplicating selection sort -- in order to find the |
| 1572 | * unique distances in the node_distance() table. |
| 1573 | * |
| 1574 | * Assumes node_distance(0,j) includes all distances in |
| 1575 | * node_distance(i,j) in order to avoid cubic time. |
| 1576 | */ |
| 1577 | next_distance = curr_distance; |
| 1578 | for (i = 0; i < nr_node_ids; i++) { |
| 1579 | for (j = 0; j < nr_node_ids; j++) { |
| 1580 | for (k = 0; k < nr_node_ids; k++) { |
| 1581 | int distance = node_distance(i, k); |
| 1582 | |
| 1583 | if (distance > curr_distance && |
| 1584 | (distance < next_distance || |
| 1585 | next_distance == curr_distance)) |
| 1586 | next_distance = distance; |
| 1587 | |
| 1588 | /* |
| 1589 | * While not a strong assumption it would be nice to know |
| 1590 | * about cases where if node A is connected to B, B is not |
| 1591 | * equally connected to A. |
| 1592 | */ |
| 1593 | if (sched_debug() && node_distance(k, i) != distance) |
| 1594 | sched_numa_warn("Node-distance not symmetric"); |
| 1595 | |
| 1596 | if (sched_debug() && i && !find_numa_distance(distance)) |
| 1597 | sched_numa_warn("Node-0 not representative"); |
| 1598 | } |
| 1599 | if (next_distance != curr_distance) { |
| 1600 | sched_domains_numa_distance[level++] = next_distance; |
| 1601 | sched_domains_numa_levels = level; |
| 1602 | curr_distance = next_distance; |
| 1603 | } else break; |
| 1604 | } |
| 1605 | |
| 1606 | /* |
| 1607 | * In case of sched_debug() we verify the above assumption. |
| 1608 | */ |
| 1609 | if (!sched_debug()) |
| 1610 | break; |
| 1611 | } |
| 1612 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1613 | /* |
Suravee Suthikulpanit | 051f3ca | 2017-09-07 02:20:05 -0500 | [diff] [blame] | 1614 | * 'level' contains the number of unique distances |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1615 | * |
| 1616 | * The sched_domains_numa_distance[] array includes the actual distance |
| 1617 | * numbers. |
| 1618 | */ |
| 1619 | |
| 1620 | /* |
| 1621 | * Here, we should temporarily reset sched_domains_numa_levels to 0. |
| 1622 | * If it fails to allocate memory for array sched_domains_numa_masks[][], |
| 1623 | * the array will contain less then 'level' members. This could be |
| 1624 | * dangerous when we use it to iterate array sched_domains_numa_masks[][] |
| 1625 | * in other functions. |
| 1626 | * |
| 1627 | * We reset it to 'level' at the end of this function. |
| 1628 | */ |
| 1629 | sched_domains_numa_levels = 0; |
| 1630 | |
| 1631 | sched_domains_numa_masks = kzalloc(sizeof(void *) * level, GFP_KERNEL); |
| 1632 | if (!sched_domains_numa_masks) |
| 1633 | return; |
| 1634 | |
| 1635 | /* |
| 1636 | * Now for each level, construct a mask per node which contains all |
| 1637 | * CPUs of nodes that are that many hops away from us. |
| 1638 | */ |
| 1639 | for (i = 0; i < level; i++) { |
| 1640 | sched_domains_numa_masks[i] = |
| 1641 | kzalloc(nr_node_ids * sizeof(void *), GFP_KERNEL); |
| 1642 | if (!sched_domains_numa_masks[i]) |
| 1643 | return; |
| 1644 | |
| 1645 | for (j = 0; j < nr_node_ids; j++) { |
| 1646 | struct cpumask *mask = kzalloc(cpumask_size(), GFP_KERNEL); |
| 1647 | if (!mask) |
| 1648 | return; |
| 1649 | |
| 1650 | sched_domains_numa_masks[i][j] = mask; |
| 1651 | |
| 1652 | for_each_node(k) { |
| 1653 | if (node_distance(j, k) > sched_domains_numa_distance[i]) |
| 1654 | continue; |
| 1655 | |
| 1656 | cpumask_or(mask, mask, cpumask_of_node(k)); |
| 1657 | } |
| 1658 | } |
| 1659 | } |
| 1660 | |
| 1661 | /* Compute default topology size */ |
| 1662 | for (i = 0; sched_domain_topology[i].mask; i++); |
| 1663 | |
| 1664 | tl = kzalloc((i + level + 1) * |
| 1665 | sizeof(struct sched_domain_topology_level), GFP_KERNEL); |
| 1666 | if (!tl) |
| 1667 | return; |
| 1668 | |
| 1669 | /* |
| 1670 | * Copy the default topology bits.. |
| 1671 | */ |
| 1672 | for (i = 0; sched_domain_topology[i].mask; i++) |
| 1673 | tl[i] = sched_domain_topology[i]; |
| 1674 | |
| 1675 | /* |
Suravee Suthikulpanit | 051f3ca | 2017-09-07 02:20:05 -0500 | [diff] [blame] | 1676 | * Add the NUMA identity distance, aka single NODE. |
| 1677 | */ |
| 1678 | tl[i++] = (struct sched_domain_topology_level){ |
| 1679 | .mask = sd_numa_mask, |
| 1680 | .numa_level = 0, |
| 1681 | SD_INIT_NAME(NODE) |
| 1682 | }; |
| 1683 | |
| 1684 | /* |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1685 | * .. and append 'j' levels of NUMA goodness. |
| 1686 | */ |
Suravee Suthikulpanit | 051f3ca | 2017-09-07 02:20:05 -0500 | [diff] [blame] | 1687 | for (j = 1; j < level; i++, j++) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1688 | tl[i] = (struct sched_domain_topology_level){ |
| 1689 | .mask = sd_numa_mask, |
| 1690 | .sd_flags = cpu_numa_flags, |
| 1691 | .flags = SDTL_OVERLAP, |
| 1692 | .numa_level = j, |
| 1693 | SD_INIT_NAME(NUMA) |
| 1694 | }; |
| 1695 | } |
| 1696 | |
| 1697 | sched_domain_topology = tl; |
| 1698 | |
| 1699 | sched_domains_numa_levels = level; |
| 1700 | sched_max_numa_distance = sched_domains_numa_distance[level - 1]; |
| 1701 | |
| 1702 | init_numa_topology_type(); |
| 1703 | } |
| 1704 | |
| 1705 | void sched_domains_numa_masks_set(unsigned int cpu) |
| 1706 | { |
| 1707 | int node = cpu_to_node(cpu); |
| 1708 | int i, j; |
| 1709 | |
| 1710 | for (i = 0; i < sched_domains_numa_levels; i++) { |
| 1711 | for (j = 0; j < nr_node_ids; j++) { |
| 1712 | if (node_distance(j, node) <= sched_domains_numa_distance[i]) |
| 1713 | cpumask_set_cpu(cpu, sched_domains_numa_masks[i][j]); |
| 1714 | } |
| 1715 | } |
| 1716 | } |
| 1717 | |
| 1718 | void sched_domains_numa_masks_clear(unsigned int cpu) |
| 1719 | { |
| 1720 | int i, j; |
| 1721 | |
| 1722 | for (i = 0; i < sched_domains_numa_levels; i++) { |
| 1723 | for (j = 0; j < nr_node_ids; j++) |
| 1724 | cpumask_clear_cpu(cpu, sched_domains_numa_masks[i][j]); |
| 1725 | } |
| 1726 | } |
| 1727 | |
Wanpeng Li | e0e8d49 | 2019-06-28 16:51:41 +0800 | [diff] [blame] | 1728 | /* |
| 1729 | * sched_numa_find_closest() - given the NUMA topology, find the cpu |
| 1730 | * closest to @cpu from @cpumask. |
| 1731 | * cpumask: cpumask to find a cpu from |
| 1732 | * cpu: cpu to be close to |
| 1733 | * |
| 1734 | * returns: cpu, or nr_cpu_ids when nothing found. |
| 1735 | */ |
| 1736 | int sched_numa_find_closest(const struct cpumask *cpus, int cpu) |
| 1737 | { |
| 1738 | int i, j = cpu_to_node(cpu); |
| 1739 | |
| 1740 | for (i = 0; i < sched_domains_numa_levels; i++) { |
| 1741 | cpu = cpumask_any_and(cpus, sched_domains_numa_masks[i][j]); |
| 1742 | if (cpu < nr_cpu_ids) |
| 1743 | return cpu; |
| 1744 | } |
| 1745 | return nr_cpu_ids; |
| 1746 | } |
| 1747 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1748 | #endif /* CONFIG_NUMA */ |
| 1749 | |
| 1750 | static int __sdt_alloc(const struct cpumask *cpu_map) |
| 1751 | { |
| 1752 | struct sched_domain_topology_level *tl; |
| 1753 | int j; |
| 1754 | |
| 1755 | for_each_sd_topology(tl) { |
| 1756 | struct sd_data *sdd = &tl->data; |
| 1757 | |
| 1758 | sdd->sd = alloc_percpu(struct sched_domain *); |
| 1759 | if (!sdd->sd) |
| 1760 | return -ENOMEM; |
| 1761 | |
| 1762 | sdd->sds = alloc_percpu(struct sched_domain_shared *); |
| 1763 | if (!sdd->sds) |
| 1764 | return -ENOMEM; |
| 1765 | |
| 1766 | sdd->sg = alloc_percpu(struct sched_group *); |
| 1767 | if (!sdd->sg) |
| 1768 | return -ENOMEM; |
| 1769 | |
| 1770 | sdd->sgc = alloc_percpu(struct sched_group_capacity *); |
| 1771 | if (!sdd->sgc) |
| 1772 | return -ENOMEM; |
| 1773 | |
| 1774 | for_each_cpu(j, cpu_map) { |
| 1775 | struct sched_domain *sd; |
| 1776 | struct sched_domain_shared *sds; |
| 1777 | struct sched_group *sg; |
| 1778 | struct sched_group_capacity *sgc; |
| 1779 | |
| 1780 | sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(), |
| 1781 | GFP_KERNEL, cpu_to_node(j)); |
| 1782 | if (!sd) |
| 1783 | return -ENOMEM; |
| 1784 | |
| 1785 | *per_cpu_ptr(sdd->sd, j) = sd; |
| 1786 | |
| 1787 | sds = kzalloc_node(sizeof(struct sched_domain_shared), |
| 1788 | GFP_KERNEL, cpu_to_node(j)); |
| 1789 | if (!sds) |
| 1790 | return -ENOMEM; |
| 1791 | |
| 1792 | *per_cpu_ptr(sdd->sds, j) = sds; |
| 1793 | |
| 1794 | sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), |
| 1795 | GFP_KERNEL, cpu_to_node(j)); |
| 1796 | if (!sg) |
| 1797 | return -ENOMEM; |
| 1798 | |
| 1799 | sg->next = sg; |
| 1800 | |
| 1801 | *per_cpu_ptr(sdd->sg, j) = sg; |
| 1802 | |
| 1803 | sgc = kzalloc_node(sizeof(struct sched_group_capacity) + cpumask_size(), |
| 1804 | GFP_KERNEL, cpu_to_node(j)); |
| 1805 | if (!sgc) |
| 1806 | return -ENOMEM; |
| 1807 | |
Peter Zijlstra | 005f874 | 2017-04-26 17:35:35 +0200 | [diff] [blame] | 1808 | #ifdef CONFIG_SCHED_DEBUG |
| 1809 | sgc->id = j; |
| 1810 | #endif |
| 1811 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1812 | *per_cpu_ptr(sdd->sgc, j) = sgc; |
| 1813 | } |
| 1814 | } |
| 1815 | |
| 1816 | return 0; |
| 1817 | } |
| 1818 | |
| 1819 | static void __sdt_free(const struct cpumask *cpu_map) |
| 1820 | { |
| 1821 | struct sched_domain_topology_level *tl; |
| 1822 | int j; |
| 1823 | |
| 1824 | for_each_sd_topology(tl) { |
| 1825 | struct sd_data *sdd = &tl->data; |
| 1826 | |
| 1827 | for_each_cpu(j, cpu_map) { |
| 1828 | struct sched_domain *sd; |
| 1829 | |
| 1830 | if (sdd->sd) { |
| 1831 | sd = *per_cpu_ptr(sdd->sd, j); |
| 1832 | if (sd && (sd->flags & SD_OVERLAP)) |
| 1833 | free_sched_groups(sd->groups, 0); |
| 1834 | kfree(*per_cpu_ptr(sdd->sd, j)); |
| 1835 | } |
| 1836 | |
| 1837 | if (sdd->sds) |
| 1838 | kfree(*per_cpu_ptr(sdd->sds, j)); |
| 1839 | if (sdd->sg) |
| 1840 | kfree(*per_cpu_ptr(sdd->sg, j)); |
| 1841 | if (sdd->sgc) |
| 1842 | kfree(*per_cpu_ptr(sdd->sgc, j)); |
| 1843 | } |
| 1844 | free_percpu(sdd->sd); |
| 1845 | sdd->sd = NULL; |
| 1846 | free_percpu(sdd->sds); |
| 1847 | sdd->sds = NULL; |
| 1848 | free_percpu(sdd->sg); |
| 1849 | sdd->sg = NULL; |
| 1850 | free_percpu(sdd->sgc); |
| 1851 | sdd->sgc = NULL; |
| 1852 | } |
| 1853 | } |
| 1854 | |
Viresh Kumar | 181a80d1 | 2017-04-27 13:58:59 +0530 | [diff] [blame] | 1855 | static struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1856 | const struct cpumask *cpu_map, struct sched_domain_attr *attr, |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1857 | struct sched_domain *child, int dflags, int cpu) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1858 | { |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1859 | struct sched_domain *sd = sd_init(tl, cpu_map, child, dflags, cpu); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1860 | |
| 1861 | if (child) { |
| 1862 | sd->level = child->level + 1; |
| 1863 | sched_domain_level_max = max(sched_domain_level_max, sd->level); |
| 1864 | child->parent = sd; |
| 1865 | |
| 1866 | if (!cpumask_subset(sched_domain_span(child), |
| 1867 | sched_domain_span(sd))) { |
| 1868 | pr_err("BUG: arch topology borken\n"); |
| 1869 | #ifdef CONFIG_SCHED_DEBUG |
| 1870 | pr_err(" the %s domain not a subset of the %s domain\n", |
| 1871 | child->name, sd->name); |
| 1872 | #endif |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 1873 | /* Fixup, ensure @sd has at least @child CPUs. */ |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1874 | cpumask_or(sched_domain_span(sd), |
| 1875 | sched_domain_span(sd), |
| 1876 | sched_domain_span(child)); |
| 1877 | } |
| 1878 | |
| 1879 | } |
| 1880 | set_domain_attribute(sd, attr); |
| 1881 | |
| 1882 | return sd; |
| 1883 | } |
| 1884 | |
| 1885 | /* |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1886 | * Find the sched_domain_topology_level where all CPU capacities are visible |
| 1887 | * for all CPUs. |
| 1888 | */ |
| 1889 | static struct sched_domain_topology_level |
| 1890 | *asym_cpu_capacity_level(const struct cpumask *cpu_map) |
| 1891 | { |
| 1892 | int i, j, asym_level = 0; |
| 1893 | bool asym = false; |
| 1894 | struct sched_domain_topology_level *tl, *asym_tl = NULL; |
| 1895 | unsigned long cap; |
| 1896 | |
| 1897 | /* Is there any asymmetry? */ |
Vincent Guittot | 8ec59c0 | 2019-06-17 17:00:17 +0200 | [diff] [blame] | 1898 | cap = arch_scale_cpu_capacity(cpumask_first(cpu_map)); |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1899 | |
| 1900 | for_each_cpu(i, cpu_map) { |
Vincent Guittot | 8ec59c0 | 2019-06-17 17:00:17 +0200 | [diff] [blame] | 1901 | if (arch_scale_cpu_capacity(i) != cap) { |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1902 | asym = true; |
| 1903 | break; |
| 1904 | } |
| 1905 | } |
| 1906 | |
| 1907 | if (!asym) |
| 1908 | return NULL; |
| 1909 | |
| 1910 | /* |
| 1911 | * Examine topology from all CPU's point of views to detect the lowest |
| 1912 | * sched_domain_topology_level where a highest capacity CPU is visible |
| 1913 | * to everyone. |
| 1914 | */ |
| 1915 | for_each_cpu(i, cpu_map) { |
Vincent Guittot | 8ec59c0 | 2019-06-17 17:00:17 +0200 | [diff] [blame] | 1916 | unsigned long max_capacity = arch_scale_cpu_capacity(i); |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1917 | int tl_id = 0; |
| 1918 | |
| 1919 | for_each_sd_topology(tl) { |
| 1920 | if (tl_id < asym_level) |
| 1921 | goto next_level; |
| 1922 | |
| 1923 | for_each_cpu_and(j, tl->mask(i), cpu_map) { |
| 1924 | unsigned long capacity; |
| 1925 | |
Vincent Guittot | 8ec59c0 | 2019-06-17 17:00:17 +0200 | [diff] [blame] | 1926 | capacity = arch_scale_cpu_capacity(j); |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1927 | |
| 1928 | if (capacity <= max_capacity) |
| 1929 | continue; |
| 1930 | |
| 1931 | max_capacity = capacity; |
| 1932 | asym_level = tl_id; |
| 1933 | asym_tl = tl; |
| 1934 | } |
| 1935 | next_level: |
| 1936 | tl_id++; |
| 1937 | } |
| 1938 | } |
| 1939 | |
| 1940 | return asym_tl; |
| 1941 | } |
| 1942 | |
| 1943 | |
| 1944 | /* |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1945 | * Build sched domains for a given set of CPUs and attach the sched domains |
| 1946 | * to the individual CPUs |
| 1947 | */ |
| 1948 | static int |
| 1949 | build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *attr) |
| 1950 | { |
Valentin Schneider | cd1cb33 | 2019-10-23 16:37:44 +0100 | [diff] [blame] | 1951 | enum s_alloc alloc_state = sa_none; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1952 | struct sched_domain *sd; |
| 1953 | struct s_data d; |
| 1954 | struct rq *rq = NULL; |
| 1955 | int i, ret = -ENOMEM; |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1956 | struct sched_domain_topology_level *tl_asym; |
Morten Rasmussen | df054e8 | 2018-07-04 11:17:39 +0100 | [diff] [blame] | 1957 | bool has_asym = false; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1958 | |
Valentin Schneider | cd1cb33 | 2019-10-23 16:37:44 +0100 | [diff] [blame] | 1959 | if (WARN_ON(cpumask_empty(cpu_map))) |
| 1960 | goto error; |
| 1961 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1962 | alloc_state = __visit_domain_allocation_hell(&d, cpu_map); |
| 1963 | if (alloc_state != sa_rootdomain) |
| 1964 | goto error; |
| 1965 | |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1966 | tl_asym = asym_cpu_capacity_level(cpu_map); |
| 1967 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1968 | /* Set up domains for CPUs specified by the cpu_map: */ |
| 1969 | for_each_cpu(i, cpu_map) { |
| 1970 | struct sched_domain_topology_level *tl; |
| 1971 | |
| 1972 | sd = NULL; |
| 1973 | for_each_sd_topology(tl) { |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1974 | int dflags = 0; |
| 1975 | |
Morten Rasmussen | df054e8 | 2018-07-04 11:17:39 +0100 | [diff] [blame] | 1976 | if (tl == tl_asym) { |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1977 | dflags |= SD_ASYM_CPUCAPACITY; |
Morten Rasmussen | df054e8 | 2018-07-04 11:17:39 +0100 | [diff] [blame] | 1978 | has_asym = true; |
| 1979 | } |
Morten Rasmussen | 05484e0 | 2018-07-20 14:32:31 +0100 | [diff] [blame] | 1980 | |
| 1981 | sd = build_sched_domain(tl, cpu_map, attr, sd, dflags, i); |
| 1982 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1983 | if (tl == sched_domain_topology) |
| 1984 | *per_cpu_ptr(d.sd, i) = sd; |
Peter Zijlstra | af85596 | 2017-04-26 17:36:41 +0200 | [diff] [blame] | 1985 | if (tl->flags & SDTL_OVERLAP) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 1986 | sd->flags |= SD_OVERLAP; |
| 1987 | if (cpumask_equal(cpu_map, sched_domain_span(sd))) |
| 1988 | break; |
| 1989 | } |
| 1990 | } |
| 1991 | |
| 1992 | /* Build the groups for the domains */ |
| 1993 | for_each_cpu(i, cpu_map) { |
| 1994 | for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { |
| 1995 | sd->span_weight = cpumask_weight(sched_domain_span(sd)); |
| 1996 | if (sd->flags & SD_OVERLAP) { |
| 1997 | if (build_overlap_sched_groups(sd, i)) |
| 1998 | goto error; |
| 1999 | } else { |
| 2000 | if (build_sched_groups(sd, i)) |
| 2001 | goto error; |
| 2002 | } |
| 2003 | } |
| 2004 | } |
| 2005 | |
| 2006 | /* Calculate CPU capacity for physical packages and nodes */ |
| 2007 | for (i = nr_cpumask_bits-1; i >= 0; i--) { |
| 2008 | if (!cpumask_test_cpu(i, cpu_map)) |
| 2009 | continue; |
| 2010 | |
| 2011 | for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { |
| 2012 | claim_allocations(i, sd); |
| 2013 | init_sched_groups_capacity(i, sd); |
| 2014 | } |
| 2015 | } |
| 2016 | |
| 2017 | /* Attach the domains */ |
| 2018 | rcu_read_lock(); |
| 2019 | for_each_cpu(i, cpu_map) { |
| 2020 | rq = cpu_rq(i); |
| 2021 | sd = *per_cpu_ptr(d.sd, i); |
| 2022 | |
| 2023 | /* Use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing: */ |
| 2024 | if (rq->cpu_capacity_orig > READ_ONCE(d.rd->max_cpu_capacity)) |
| 2025 | WRITE_ONCE(d.rd->max_cpu_capacity, rq->cpu_capacity_orig); |
| 2026 | |
| 2027 | cpu_attach_domain(sd, d.rd, i); |
| 2028 | } |
| 2029 | rcu_read_unlock(); |
| 2030 | |
Morten Rasmussen | df054e8 | 2018-07-04 11:17:39 +0100 | [diff] [blame] | 2031 | if (has_asym) |
Valentin Schneider | e284df7 | 2019-10-23 16:37:45 +0100 | [diff] [blame] | 2032 | static_branch_inc_cpuslocked(&sched_asym_cpucapacity); |
Morten Rasmussen | df054e8 | 2018-07-04 11:17:39 +0100 | [diff] [blame] | 2033 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2034 | if (rq && sched_debug_enabled) { |
Juri Lelli | bf5015a | 2018-05-24 17:29:36 +0200 | [diff] [blame] | 2035 | pr_info("root domain span: %*pbl (max cpu_capacity = %lu)\n", |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2036 | cpumask_pr_args(cpu_map), rq->rd->max_cpu_capacity); |
| 2037 | } |
| 2038 | |
| 2039 | ret = 0; |
| 2040 | error: |
| 2041 | __free_domain_allocs(&d, alloc_state, cpu_map); |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 2042 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2043 | return ret; |
| 2044 | } |
| 2045 | |
| 2046 | /* Current sched domains: */ |
| 2047 | static cpumask_var_t *doms_cur; |
| 2048 | |
| 2049 | /* Number of sched domains in 'doms_cur': */ |
| 2050 | static int ndoms_cur; |
| 2051 | |
| 2052 | /* Attribues of custom domains in 'doms_cur' */ |
| 2053 | static struct sched_domain_attr *dattr_cur; |
| 2054 | |
| 2055 | /* |
| 2056 | * Special case: If a kmalloc() of a doms_cur partition (array of |
| 2057 | * cpumask) fails, then fallback to a single sched domain, |
| 2058 | * as determined by the single cpumask fallback_doms. |
| 2059 | */ |
Peter Zijlstra | 8d5dc51 | 2017-04-25 15:29:40 +0200 | [diff] [blame] | 2060 | static cpumask_var_t fallback_doms; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2061 | |
| 2062 | /* |
| 2063 | * arch_update_cpu_topology lets virtualized architectures update the |
| 2064 | * CPU core maps. It is supposed to return 1 if the topology changed |
| 2065 | * or 0 if it stayed the same. |
| 2066 | */ |
| 2067 | int __weak arch_update_cpu_topology(void) |
| 2068 | { |
| 2069 | return 0; |
| 2070 | } |
| 2071 | |
| 2072 | cpumask_var_t *alloc_sched_domains(unsigned int ndoms) |
| 2073 | { |
| 2074 | int i; |
| 2075 | cpumask_var_t *doms; |
| 2076 | |
Kees Cook | 6da2ec5 | 2018-06-12 13:55:00 -0700 | [diff] [blame] | 2077 | doms = kmalloc_array(ndoms, sizeof(*doms), GFP_KERNEL); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2078 | if (!doms) |
| 2079 | return NULL; |
| 2080 | for (i = 0; i < ndoms; i++) { |
| 2081 | if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) { |
| 2082 | free_sched_domains(doms, i); |
| 2083 | return NULL; |
| 2084 | } |
| 2085 | } |
| 2086 | return doms; |
| 2087 | } |
| 2088 | |
| 2089 | void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms) |
| 2090 | { |
| 2091 | unsigned int i; |
| 2092 | for (i = 0; i < ndoms; i++) |
| 2093 | free_cpumask_var(doms[i]); |
| 2094 | kfree(doms); |
| 2095 | } |
| 2096 | |
| 2097 | /* |
Juri Lelli | cb0c041 | 2018-12-19 14:34:45 +0100 | [diff] [blame] | 2098 | * Set up scheduler domains and groups. For now this just excludes isolated |
| 2099 | * CPUs, but could be used to exclude other special cases in the future. |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2100 | */ |
Peter Zijlstra | 8d5dc51 | 2017-04-25 15:29:40 +0200 | [diff] [blame] | 2101 | int sched_init_domains(const struct cpumask *cpu_map) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2102 | { |
| 2103 | int err; |
| 2104 | |
Peter Zijlstra | 8d5dc51 | 2017-04-25 15:29:40 +0200 | [diff] [blame] | 2105 | zalloc_cpumask_var(&sched_domains_tmpmask, GFP_KERNEL); |
Peter Zijlstra | 1676330 | 2017-04-25 14:31:11 +0200 | [diff] [blame] | 2106 | zalloc_cpumask_var(&sched_domains_tmpmask2, GFP_KERNEL); |
Peter Zijlstra | 8d5dc51 | 2017-04-25 15:29:40 +0200 | [diff] [blame] | 2107 | zalloc_cpumask_var(&fallback_doms, GFP_KERNEL); |
| 2108 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2109 | arch_update_cpu_topology(); |
| 2110 | ndoms_cur = 1; |
| 2111 | doms_cur = alloc_sched_domains(ndoms_cur); |
| 2112 | if (!doms_cur) |
| 2113 | doms_cur = &fallback_doms; |
Frederic Weisbecker | edb9382 | 2017-10-27 04:42:37 +0200 | [diff] [blame] | 2114 | cpumask_and(doms_cur[0], cpu_map, housekeeping_cpumask(HK_FLAG_DOMAIN)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2115 | err = build_sched_domains(doms_cur[0], NULL); |
| 2116 | register_sched_domain_sysctl(); |
| 2117 | |
| 2118 | return err; |
| 2119 | } |
| 2120 | |
| 2121 | /* |
| 2122 | * Detach sched domains from a group of CPUs specified in cpu_map |
| 2123 | * These CPUs will now be attached to the NULL domain |
| 2124 | */ |
| 2125 | static void detach_destroy_domains(const struct cpumask *cpu_map) |
| 2126 | { |
Valentin Schneider | e284df7 | 2019-10-23 16:37:45 +0100 | [diff] [blame] | 2127 | unsigned int cpu = cpumask_any(cpu_map); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2128 | int i; |
| 2129 | |
Valentin Schneider | e284df7 | 2019-10-23 16:37:45 +0100 | [diff] [blame] | 2130 | if (rcu_access_pointer(per_cpu(sd_asym_cpucapacity, cpu))) |
| 2131 | static_branch_dec_cpuslocked(&sched_asym_cpucapacity); |
| 2132 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2133 | rcu_read_lock(); |
| 2134 | for_each_cpu(i, cpu_map) |
| 2135 | cpu_attach_domain(NULL, &def_root_domain, i); |
| 2136 | rcu_read_unlock(); |
| 2137 | } |
| 2138 | |
| 2139 | /* handle null as "default" */ |
| 2140 | static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur, |
| 2141 | struct sched_domain_attr *new, int idx_new) |
| 2142 | { |
| 2143 | struct sched_domain_attr tmp; |
| 2144 | |
| 2145 | /* Fast path: */ |
| 2146 | if (!new && !cur) |
| 2147 | return 1; |
| 2148 | |
| 2149 | tmp = SD_ATTR_INIT; |
Ingo Molnar | 97fb7a0 | 2018-03-03 14:01:12 +0100 | [diff] [blame] | 2150 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2151 | return !memcmp(cur ? (cur + idx_cur) : &tmp, |
| 2152 | new ? (new + idx_new) : &tmp, |
| 2153 | sizeof(struct sched_domain_attr)); |
| 2154 | } |
| 2155 | |
| 2156 | /* |
| 2157 | * Partition sched domains as specified by the 'ndoms_new' |
| 2158 | * cpumasks in the array doms_new[] of cpumasks. This compares |
| 2159 | * doms_new[] to the current sched domain partitioning, doms_cur[]. |
| 2160 | * It destroys each deleted domain and builds each new domain. |
| 2161 | * |
| 2162 | * 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'. |
| 2163 | * The masks don't intersect (don't overlap.) We should setup one |
| 2164 | * sched domain for each mask. CPUs not in any of the cpumasks will |
| 2165 | * not be load balanced. If the same cpumask appears both in the |
| 2166 | * current 'doms_cur' domains and in the new 'doms_new', we can leave |
| 2167 | * it as it is. |
| 2168 | * |
| 2169 | * The passed in 'doms_new' should be allocated using |
| 2170 | * alloc_sched_domains. This routine takes ownership of it and will |
| 2171 | * free_sched_domains it when done with it. If the caller failed the |
| 2172 | * alloc call, then it can pass in doms_new == NULL && ndoms_new == 1, |
| 2173 | * and partition_sched_domains() will fallback to the single partition |
| 2174 | * 'fallback_doms', it also forces the domains to be rebuilt. |
| 2175 | * |
| 2176 | * If doms_new == NULL it will be replaced with cpu_online_mask. |
| 2177 | * ndoms_new == 0 is a special case for destroying existing domains, |
| 2178 | * and it will not create the default domain. |
| 2179 | * |
Mathieu Poirier | c22645f | 2019-07-19 15:59:53 +0200 | [diff] [blame] | 2180 | * Call with hotplug lock and sched_domains_mutex held |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2181 | */ |
Mathieu Poirier | c22645f | 2019-07-19 15:59:53 +0200 | [diff] [blame] | 2182 | void partition_sched_domains_locked(int ndoms_new, cpumask_var_t doms_new[], |
| 2183 | struct sched_domain_attr *dattr_new) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2184 | { |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 2185 | bool __maybe_unused has_eas = false; |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2186 | int i, j, n; |
| 2187 | int new_topology; |
| 2188 | |
Mathieu Poirier | c22645f | 2019-07-19 15:59:53 +0200 | [diff] [blame] | 2189 | lockdep_assert_held(&sched_domains_mutex); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2190 | |
| 2191 | /* Always unregister in case we don't destroy any domains: */ |
| 2192 | unregister_sched_domain_sysctl(); |
| 2193 | |
| 2194 | /* Let the architecture update CPU core mappings: */ |
| 2195 | new_topology = arch_update_cpu_topology(); |
| 2196 | |
Peter Zijlstra | 09e0dd8 | 2017-08-08 12:16:24 +0200 | [diff] [blame] | 2197 | if (!doms_new) { |
| 2198 | WARN_ON_ONCE(dattr_new); |
| 2199 | n = 0; |
| 2200 | doms_new = alloc_sched_domains(1); |
| 2201 | if (doms_new) { |
| 2202 | n = 1; |
Frederic Weisbecker | edb9382 | 2017-10-27 04:42:37 +0200 | [diff] [blame] | 2203 | cpumask_and(doms_new[0], cpu_active_mask, |
| 2204 | housekeeping_cpumask(HK_FLAG_DOMAIN)); |
Peter Zijlstra | 09e0dd8 | 2017-08-08 12:16:24 +0200 | [diff] [blame] | 2205 | } |
| 2206 | } else { |
| 2207 | n = ndoms_new; |
| 2208 | } |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2209 | |
| 2210 | /* Destroy deleted domains: */ |
| 2211 | for (i = 0; i < ndoms_cur; i++) { |
| 2212 | for (j = 0; j < n && !new_topology; j++) { |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2213 | if (cpumask_equal(doms_cur[i], doms_new[j]) && |
Mathieu Poirier | f9a25f7 | 2019-07-19 15:59:55 +0200 | [diff] [blame] | 2214 | dattrs_equal(dattr_cur, i, dattr_new, j)) { |
| 2215 | struct root_domain *rd; |
| 2216 | |
| 2217 | /* |
| 2218 | * This domain won't be destroyed and as such |
| 2219 | * its dl_bw->total_bw needs to be cleared. It |
| 2220 | * will be recomputed in function |
| 2221 | * update_tasks_root_domain(). |
| 2222 | */ |
| 2223 | rd = cpu_rq(cpumask_any(doms_cur[i]))->rd; |
| 2224 | dl_clear_root_domain(rd); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2225 | goto match1; |
Mathieu Poirier | f9a25f7 | 2019-07-19 15:59:55 +0200 | [diff] [blame] | 2226 | } |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2227 | } |
| 2228 | /* No match - a current sched domain not in new doms_new[] */ |
| 2229 | detach_destroy_domains(doms_cur[i]); |
| 2230 | match1: |
| 2231 | ; |
| 2232 | } |
| 2233 | |
| 2234 | n = ndoms_cur; |
Peter Zijlstra | 09e0dd8 | 2017-08-08 12:16:24 +0200 | [diff] [blame] | 2235 | if (!doms_new) { |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2236 | n = 0; |
| 2237 | doms_new = &fallback_doms; |
Frederic Weisbecker | edb9382 | 2017-10-27 04:42:37 +0200 | [diff] [blame] | 2238 | cpumask_and(doms_new[0], cpu_active_mask, |
| 2239 | housekeeping_cpumask(HK_FLAG_DOMAIN)); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2240 | } |
| 2241 | |
| 2242 | /* Build new domains: */ |
| 2243 | for (i = 0; i < ndoms_new; i++) { |
| 2244 | for (j = 0; j < n && !new_topology; j++) { |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2245 | if (cpumask_equal(doms_new[i], doms_cur[j]) && |
| 2246 | dattrs_equal(dattr_new, i, dattr_cur, j)) |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2247 | goto match2; |
| 2248 | } |
| 2249 | /* No match - add a new doms_new */ |
| 2250 | build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL); |
| 2251 | match2: |
| 2252 | ; |
| 2253 | } |
| 2254 | |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 2255 | #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2256 | /* Build perf. domains: */ |
| 2257 | for (i = 0; i < ndoms_new; i++) { |
Quentin Perret | 531b5c9 | 2018-12-03 09:56:21 +0000 | [diff] [blame] | 2258 | for (j = 0; j < n && !sched_energy_update; j++) { |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2259 | if (cpumask_equal(doms_new[i], doms_cur[j]) && |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 2260 | cpu_rq(cpumask_first(doms_cur[j]))->rd->pd) { |
| 2261 | has_eas = true; |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2262 | goto match3; |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 2263 | } |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2264 | } |
| 2265 | /* No match - add perf. domains for a new rd */ |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 2266 | has_eas |= build_perf_domains(doms_new[i]); |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2267 | match3: |
| 2268 | ; |
| 2269 | } |
Quentin Perret | 1f74de8 | 2018-12-03 09:56:22 +0000 | [diff] [blame] | 2270 | sched_energy_set(has_eas); |
Quentin Perret | 6aa140f | 2018-12-03 09:56:18 +0000 | [diff] [blame] | 2271 | #endif |
| 2272 | |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2273 | /* Remember the new sched domains: */ |
| 2274 | if (doms_cur != &fallback_doms) |
| 2275 | free_sched_domains(doms_cur, ndoms_cur); |
| 2276 | |
| 2277 | kfree(dattr_cur); |
| 2278 | doms_cur = doms_new; |
| 2279 | dattr_cur = dattr_new; |
| 2280 | ndoms_cur = ndoms_new; |
| 2281 | |
| 2282 | register_sched_domain_sysctl(); |
Mathieu Poirier | c22645f | 2019-07-19 15:59:53 +0200 | [diff] [blame] | 2283 | } |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2284 | |
Mathieu Poirier | c22645f | 2019-07-19 15:59:53 +0200 | [diff] [blame] | 2285 | /* |
| 2286 | * Call with hotplug lock held |
| 2287 | */ |
| 2288 | void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], |
| 2289 | struct sched_domain_attr *dattr_new) |
| 2290 | { |
| 2291 | mutex_lock(&sched_domains_mutex); |
| 2292 | partition_sched_domains_locked(ndoms_new, doms_new, dattr_new); |
Ingo Molnar | f2cb136 | 2017-02-01 13:10:18 +0100 | [diff] [blame] | 2293 | mutex_unlock(&sched_domains_mutex); |
| 2294 | } |