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1/*2 * Copyright(c) 2011-2016 Intel Corporation. All rights reserved.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice (including the next12 * paragraph) shall be included in all copies or substantial portions of the13 * Software.14 *15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE21 * SOFTWARE.22 *23 * Authors:24 * Anhua Xu25 * Kevin Tian <kevin.tian@intel.com>26 *27 * Contributors:28 * Min He <min.he@intel.com>29 * Bing Niu <bing.niu@intel.com>30 * Zhi Wang <zhi.a.wang@intel.com>31 *32 */33 34#include "i915_drv.h"35#include "gvt.h"36 37static bool vgpu_has_pending_workload(struct intel_vgpu *vgpu)38{39 enum intel_engine_id i;40 struct intel_engine_cs *engine;41 42 for_each_engine(engine, vgpu->gvt->gt, i) {43 if (!list_empty(workload_q_head(vgpu, engine)))44 return true;45 }46 47 return false;48}49 50/* We give 2 seconds higher prio for vGPU during start */51#define GVT_SCHED_VGPU_PRI_TIME 252 53struct vgpu_sched_data {54 struct list_head lru_list;55 struct intel_vgpu *vgpu;56 bool active;57 bool pri_sched;58 ktime_t pri_time;59 ktime_t sched_in_time;60 ktime_t sched_time;61 ktime_t left_ts;62 ktime_t allocated_ts;63 64 struct vgpu_sched_ctl sched_ctl;65};66 67struct gvt_sched_data {68 struct intel_gvt *gvt;69 struct hrtimer timer;70 unsigned long period;71 struct list_head lru_runq_head;72 ktime_t expire_time;73};74 75static void vgpu_update_timeslice(struct intel_vgpu *vgpu, ktime_t cur_time)76{77 ktime_t delta_ts;78 struct vgpu_sched_data *vgpu_data;79 80 if (!vgpu || vgpu == vgpu->gvt->idle_vgpu)81 return;82 83 vgpu_data = vgpu->sched_data;84 delta_ts = ktime_sub(cur_time, vgpu_data->sched_in_time);85 vgpu_data->sched_time = ktime_add(vgpu_data->sched_time, delta_ts);86 vgpu_data->left_ts = ktime_sub(vgpu_data->left_ts, delta_ts);87 vgpu_data->sched_in_time = cur_time;88}89 90#define GVT_TS_BALANCE_PERIOD_MS 10091#define GVT_TS_BALANCE_STAGE_NUM 1092 93static void gvt_balance_timeslice(struct gvt_sched_data *sched_data)94{95 struct vgpu_sched_data *vgpu_data;96 struct list_head *pos;97 static u64 stage_check;98 int stage = stage_check++ % GVT_TS_BALANCE_STAGE_NUM;99 100 /* The timeslice accumulation reset at stage 0, which is101 * allocated again without adding previous debt.102 */103 if (stage == 0) {104 int total_weight = 0;105 ktime_t fair_timeslice;106 107 list_for_each(pos, &sched_data->lru_runq_head) {108 vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list);109 total_weight += vgpu_data->sched_ctl.weight;110 }111 112 list_for_each(pos, &sched_data->lru_runq_head) {113 vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list);114 fair_timeslice = ktime_divns(ms_to_ktime(GVT_TS_BALANCE_PERIOD_MS),115 total_weight) * vgpu_data->sched_ctl.weight;116 117 vgpu_data->allocated_ts = fair_timeslice;118 vgpu_data->left_ts = vgpu_data->allocated_ts;119 }120 } else {121 list_for_each(pos, &sched_data->lru_runq_head) {122 vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list);123 124 /* timeslice for next 100ms should add the left/debt125 * slice of previous stages.126 */127 vgpu_data->left_ts += vgpu_data->allocated_ts;128 }129 }130}131 132static void try_to_schedule_next_vgpu(struct intel_gvt *gvt)133{134 struct intel_gvt_workload_scheduler *scheduler = &gvt->scheduler;135 enum intel_engine_id i;136 struct intel_engine_cs *engine;137 struct vgpu_sched_data *vgpu_data;138 ktime_t cur_time;139 140 /* no need to schedule if next_vgpu is the same with current_vgpu,141 * let scheduler chose next_vgpu again by setting it to NULL.142 */143 if (scheduler->next_vgpu == scheduler->current_vgpu) {144 scheduler->next_vgpu = NULL;145 return;146 }147 148 /*149 * after the flag is set, workload dispatch thread will150 * stop dispatching workload for current vgpu151 */152 scheduler->need_reschedule = true;153 154 /* still have uncompleted workload? */155 for_each_engine(engine, gvt->gt, i) {156 if (scheduler->current_workload[engine->id])157 return;158 }159 160 cur_time = ktime_get();161 vgpu_update_timeslice(scheduler->current_vgpu, cur_time);162 vgpu_data = scheduler->next_vgpu->sched_data;163 vgpu_data->sched_in_time = cur_time;164 165 /* switch current vgpu */166 scheduler->current_vgpu = scheduler->next_vgpu;167 scheduler->next_vgpu = NULL;168 169 scheduler->need_reschedule = false;170 171 /* wake up workload dispatch thread */172 for_each_engine(engine, gvt->gt, i)173 wake_up(&scheduler->waitq[engine->id]);174}175 176static struct intel_vgpu *find_busy_vgpu(struct gvt_sched_data *sched_data)177{178 struct vgpu_sched_data *vgpu_data;179 struct intel_vgpu *vgpu = NULL;180 struct list_head *head = &sched_data->lru_runq_head;181 struct list_head *pos;182 183 /* search a vgpu with pending workload */184 list_for_each(pos, head) {185 186 vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list);187 if (!vgpu_has_pending_workload(vgpu_data->vgpu))188 continue;189 190 if (vgpu_data->pri_sched) {191 if (ktime_before(ktime_get(), vgpu_data->pri_time)) {192 vgpu = vgpu_data->vgpu;193 break;194 } else195 vgpu_data->pri_sched = false;196 }197 198 /* Return the vGPU only if it has time slice left */199 if (vgpu_data->left_ts > 0) {200 vgpu = vgpu_data->vgpu;201 break;202 }203 }204 205 return vgpu;206}207 208/* in nanosecond */209#define GVT_DEFAULT_TIME_SLICE 1000000210 211static void tbs_sched_func(struct gvt_sched_data *sched_data)212{213 struct intel_gvt *gvt = sched_data->gvt;214 struct intel_gvt_workload_scheduler *scheduler = &gvt->scheduler;215 struct vgpu_sched_data *vgpu_data;216 struct intel_vgpu *vgpu = NULL;217 218 /* no active vgpu or has already had a target */219 if (list_empty(&sched_data->lru_runq_head) || scheduler->next_vgpu)220 goto out;221 222 vgpu = find_busy_vgpu(sched_data);223 if (vgpu) {224 scheduler->next_vgpu = vgpu;225 vgpu_data = vgpu->sched_data;226 if (!vgpu_data->pri_sched) {227 /* Move the last used vGPU to the tail of lru_list */228 list_del_init(&vgpu_data->lru_list);229 list_add_tail(&vgpu_data->lru_list,230 &sched_data->lru_runq_head);231 }232 } else {233 scheduler->next_vgpu = gvt->idle_vgpu;234 }235out:236 if (scheduler->next_vgpu)237 try_to_schedule_next_vgpu(gvt);238}239 240void intel_gvt_schedule(struct intel_gvt *gvt)241{242 struct gvt_sched_data *sched_data = gvt->scheduler.sched_data;243 ktime_t cur_time;244 245 mutex_lock(&gvt->sched_lock);246 cur_time = ktime_get();247 248 if (test_and_clear_bit(INTEL_GVT_REQUEST_SCHED,249 (void *)&gvt->service_request)) {250 if (cur_time >= sched_data->expire_time) {251 gvt_balance_timeslice(sched_data);252 sched_data->expire_time = ktime_add_ms(253 cur_time, GVT_TS_BALANCE_PERIOD_MS);254 }255 }256 clear_bit(INTEL_GVT_REQUEST_EVENT_SCHED, (void *)&gvt->service_request);257 258 vgpu_update_timeslice(gvt->scheduler.current_vgpu, cur_time);259 tbs_sched_func(sched_data);260 261 mutex_unlock(&gvt->sched_lock);262}263 264static enum hrtimer_restart tbs_timer_fn(struct hrtimer *timer_data)265{266 struct gvt_sched_data *data;267 268 data = container_of(timer_data, struct gvt_sched_data, timer);269 270 intel_gvt_request_service(data->gvt, INTEL_GVT_REQUEST_SCHED);271 272 hrtimer_add_expires_ns(&data->timer, data->period);273 274 return HRTIMER_RESTART;275}276 277static int tbs_sched_init(struct intel_gvt *gvt)278{279 struct intel_gvt_workload_scheduler *scheduler =280 &gvt->scheduler;281 282 struct gvt_sched_data *data;283 284 data = kzalloc(sizeof(*data), GFP_KERNEL);285 if (!data)286 return -ENOMEM;287 288 INIT_LIST_HEAD(&data->lru_runq_head);289 hrtimer_init(&data->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);290 data->timer.function = tbs_timer_fn;291 data->period = GVT_DEFAULT_TIME_SLICE;292 data->gvt = gvt;293 294 scheduler->sched_data = data;295 296 return 0;297}298 299static void tbs_sched_clean(struct intel_gvt *gvt)300{301 struct intel_gvt_workload_scheduler *scheduler =302 &gvt->scheduler;303 struct gvt_sched_data *data = scheduler->sched_data;304 305 hrtimer_cancel(&data->timer);306 307 kfree(data);308 scheduler->sched_data = NULL;309}310 311static int tbs_sched_init_vgpu(struct intel_vgpu *vgpu)312{313 struct vgpu_sched_data *data;314 315 data = kzalloc(sizeof(*data), GFP_KERNEL);316 if (!data)317 return -ENOMEM;318 319 data->sched_ctl.weight = vgpu->sched_ctl.weight;320 data->vgpu = vgpu;321 INIT_LIST_HEAD(&data->lru_list);322 323 vgpu->sched_data = data;324 325 return 0;326}327 328static void tbs_sched_clean_vgpu(struct intel_vgpu *vgpu)329{330 struct intel_gvt *gvt = vgpu->gvt;331 struct gvt_sched_data *sched_data = gvt->scheduler.sched_data;332 333 kfree(vgpu->sched_data);334 vgpu->sched_data = NULL;335 336 /* this vgpu id has been removed */337 if (idr_is_empty(&gvt->vgpu_idr))338 hrtimer_cancel(&sched_data->timer);339}340 341static void tbs_sched_start_schedule(struct intel_vgpu *vgpu)342{343 struct gvt_sched_data *sched_data = vgpu->gvt->scheduler.sched_data;344 struct vgpu_sched_data *vgpu_data = vgpu->sched_data;345 ktime_t now;346 347 if (!list_empty(&vgpu_data->lru_list))348 return;349 350 now = ktime_get();351 vgpu_data->pri_time = ktime_add(now,352 ktime_set(GVT_SCHED_VGPU_PRI_TIME, 0));353 vgpu_data->pri_sched = true;354 355 list_add(&vgpu_data->lru_list, &sched_data->lru_runq_head);356 357 if (!hrtimer_active(&sched_data->timer))358 hrtimer_start(&sched_data->timer, ktime_add_ns(ktime_get(),359 sched_data->period), HRTIMER_MODE_ABS);360 vgpu_data->active = true;361}362 363static void tbs_sched_stop_schedule(struct intel_vgpu *vgpu)364{365 struct vgpu_sched_data *vgpu_data = vgpu->sched_data;366 367 list_del_init(&vgpu_data->lru_list);368 vgpu_data->active = false;369}370 371static const struct intel_gvt_sched_policy_ops tbs_schedule_ops = {372 .init = tbs_sched_init,373 .clean = tbs_sched_clean,374 .init_vgpu = tbs_sched_init_vgpu,375 .clean_vgpu = tbs_sched_clean_vgpu,376 .start_schedule = tbs_sched_start_schedule,377 .stop_schedule = tbs_sched_stop_schedule,378};379 380int intel_gvt_init_sched_policy(struct intel_gvt *gvt)381{382 int ret;383 384 mutex_lock(&gvt->sched_lock);385 gvt->scheduler.sched_ops = &tbs_schedule_ops;386 ret = gvt->scheduler.sched_ops->init(gvt);387 mutex_unlock(&gvt->sched_lock);388 389 return ret;390}391 392void intel_gvt_clean_sched_policy(struct intel_gvt *gvt)393{394 mutex_lock(&gvt->sched_lock);395 gvt->scheduler.sched_ops->clean(gvt);396 mutex_unlock(&gvt->sched_lock);397}398 399/* for per-vgpu scheduler policy, there are 2 per-vgpu data:400 * sched_data, and sched_ctl. We see these 2 data as part of401 * the global scheduler which are proteced by gvt->sched_lock.402 * Caller should make their decision if the vgpu_lock should403 * be hold outside.404 */405 406int intel_vgpu_init_sched_policy(struct intel_vgpu *vgpu)407{408 int ret;409 410 mutex_lock(&vgpu->gvt->sched_lock);411 ret = vgpu->gvt->scheduler.sched_ops->init_vgpu(vgpu);412 mutex_unlock(&vgpu->gvt->sched_lock);413 414 return ret;415}416 417void intel_vgpu_clean_sched_policy(struct intel_vgpu *vgpu)418{419 mutex_lock(&vgpu->gvt->sched_lock);420 vgpu->gvt->scheduler.sched_ops->clean_vgpu(vgpu);421 mutex_unlock(&vgpu->gvt->sched_lock);422}423 424void intel_vgpu_start_schedule(struct intel_vgpu *vgpu)425{426 struct vgpu_sched_data *vgpu_data = vgpu->sched_data;427 428 mutex_lock(&vgpu->gvt->sched_lock);429 if (!vgpu_data->active) {430 gvt_dbg_core("vgpu%d: start schedule\n", vgpu->id);431 vgpu->gvt->scheduler.sched_ops->start_schedule(vgpu);432 }433 mutex_unlock(&vgpu->gvt->sched_lock);434}435 436void intel_gvt_kick_schedule(struct intel_gvt *gvt)437{438 mutex_lock(&gvt->sched_lock);439 intel_gvt_request_service(gvt, INTEL_GVT_REQUEST_EVENT_SCHED);440 mutex_unlock(&gvt->sched_lock);441}442 443void intel_vgpu_stop_schedule(struct intel_vgpu *vgpu)444{445 struct intel_gvt_workload_scheduler *scheduler =446 &vgpu->gvt->scheduler;447 struct vgpu_sched_data *vgpu_data = vgpu->sched_data;448 struct drm_i915_private *dev_priv = vgpu->gvt->gt->i915;449 struct intel_engine_cs *engine;450 enum intel_engine_id id;451 452 if (!vgpu_data->active)453 return;454 455 gvt_dbg_core("vgpu%d: stop schedule\n", vgpu->id);456 457 mutex_lock(&vgpu->gvt->sched_lock);458 scheduler->sched_ops->stop_schedule(vgpu);459 460 if (scheduler->next_vgpu == vgpu)461 scheduler->next_vgpu = NULL;462 463 if (scheduler->current_vgpu == vgpu) {464 /* stop workload dispatching */465 scheduler->need_reschedule = true;466 scheduler->current_vgpu = NULL;467 }468 469 intel_runtime_pm_get(&dev_priv->runtime_pm);470 spin_lock_bh(&scheduler->mmio_context_lock);471 for_each_engine(engine, vgpu->gvt->gt, id) {472 if (scheduler->engine_owner[engine->id] == vgpu) {473 intel_gvt_switch_mmio(vgpu, NULL, engine);474 scheduler->engine_owner[engine->id] = NULL;475 }476 }477 spin_unlock_bh(&scheduler->mmio_context_lock);478 intel_runtime_pm_put_unchecked(&dev_priv->runtime_pm);479 mutex_unlock(&vgpu->gvt->sched_lock);480}481