| /* |
| * Copyright(c) 2011-2016 Intel Corporation. All rights reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| * SOFTWARE. |
| * |
| * Authors: |
| * Anhua Xu |
| * Kevin Tian <kevin.tian@intel.com> |
| * |
| * Contributors: |
| * Min He <min.he@intel.com> |
| * Bing Niu <bing.niu@intel.com> |
| * Zhi Wang <zhi.a.wang@intel.com> |
| * |
| */ |
| |
| #include "i915_drv.h" |
| #include "gvt.h" |
| |
| static bool vgpu_has_pending_workload(struct intel_vgpu *vgpu) |
| { |
| enum intel_engine_id i; |
| struct intel_engine_cs *engine; |
| |
| for_each_engine(engine, vgpu->gvt->dev_priv, i) { |
| if (!list_empty(workload_q_head(vgpu, i))) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| struct vgpu_sched_data { |
| struct list_head lru_list; |
| struct intel_vgpu *vgpu; |
| |
| ktime_t sched_in_time; |
| ktime_t sched_out_time; |
| ktime_t sched_time; |
| ktime_t left_ts; |
| ktime_t allocated_ts; |
| |
| struct vgpu_sched_ctl sched_ctl; |
| }; |
| |
| struct gvt_sched_data { |
| struct intel_gvt *gvt; |
| struct hrtimer timer; |
| unsigned long period; |
| struct list_head lru_runq_head; |
| }; |
| |
| static void vgpu_update_timeslice(struct intel_vgpu *pre_vgpu) |
| { |
| ktime_t delta_ts; |
| struct vgpu_sched_data *vgpu_data = pre_vgpu->sched_data; |
| |
| delta_ts = vgpu_data->sched_out_time - vgpu_data->sched_in_time; |
| |
| vgpu_data->sched_time += delta_ts; |
| vgpu_data->left_ts -= delta_ts; |
| } |
| |
| #define GVT_TS_BALANCE_PERIOD_MS 100 |
| #define GVT_TS_BALANCE_STAGE_NUM 10 |
| |
| static void gvt_balance_timeslice(struct gvt_sched_data *sched_data) |
| { |
| struct vgpu_sched_data *vgpu_data; |
| struct list_head *pos; |
| static uint64_t stage_check; |
| int stage = stage_check++ % GVT_TS_BALANCE_STAGE_NUM; |
| |
| /* The timeslice accumulation reset at stage 0, which is |
| * allocated again without adding previous debt. |
| */ |
| if (stage == 0) { |
| int total_weight = 0; |
| ktime_t fair_timeslice; |
| |
| list_for_each(pos, &sched_data->lru_runq_head) { |
| vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list); |
| total_weight += vgpu_data->sched_ctl.weight; |
| } |
| |
| list_for_each(pos, &sched_data->lru_runq_head) { |
| vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list); |
| fair_timeslice = ms_to_ktime(GVT_TS_BALANCE_PERIOD_MS) * |
| vgpu_data->sched_ctl.weight / |
| total_weight; |
| |
| vgpu_data->allocated_ts = fair_timeslice; |
| vgpu_data->left_ts = vgpu_data->allocated_ts; |
| } |
| } else { |
| list_for_each(pos, &sched_data->lru_runq_head) { |
| vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list); |
| |
| /* timeslice for next 100ms should add the left/debt |
| * slice of previous stages. |
| */ |
| vgpu_data->left_ts += vgpu_data->allocated_ts; |
| } |
| } |
| } |
| |
| static void try_to_schedule_next_vgpu(struct intel_gvt *gvt) |
| { |
| struct intel_gvt_workload_scheduler *scheduler = &gvt->scheduler; |
| enum intel_engine_id i; |
| struct intel_engine_cs *engine; |
| struct vgpu_sched_data *vgpu_data; |
| ktime_t cur_time; |
| |
| /* no target to schedule */ |
| if (!scheduler->next_vgpu) |
| return; |
| |
| /* |
| * after the flag is set, workload dispatch thread will |
| * stop dispatching workload for current vgpu |
| */ |
| scheduler->need_reschedule = true; |
| |
| /* still have uncompleted workload? */ |
| for_each_engine(engine, gvt->dev_priv, i) { |
| if (scheduler->current_workload[i]) |
| return; |
| } |
| |
| cur_time = ktime_get(); |
| if (scheduler->current_vgpu) { |
| vgpu_data = scheduler->current_vgpu->sched_data; |
| vgpu_data->sched_out_time = cur_time; |
| vgpu_update_timeslice(scheduler->current_vgpu); |
| } |
| vgpu_data = scheduler->next_vgpu->sched_data; |
| vgpu_data->sched_in_time = cur_time; |
| |
| /* switch current vgpu */ |
| scheduler->current_vgpu = scheduler->next_vgpu; |
| scheduler->next_vgpu = NULL; |
| |
| scheduler->need_reschedule = false; |
| |
| /* wake up workload dispatch thread */ |
| for_each_engine(engine, gvt->dev_priv, i) |
| wake_up(&scheduler->waitq[i]); |
| } |
| |
| static struct intel_vgpu *find_busy_vgpu(struct gvt_sched_data *sched_data) |
| { |
| struct vgpu_sched_data *vgpu_data; |
| struct intel_vgpu *vgpu = NULL; |
| struct list_head *head = &sched_data->lru_runq_head; |
| struct list_head *pos; |
| |
| /* search a vgpu with pending workload */ |
| list_for_each(pos, head) { |
| |
| vgpu_data = container_of(pos, struct vgpu_sched_data, lru_list); |
| if (!vgpu_has_pending_workload(vgpu_data->vgpu)) |
| continue; |
| |
| /* Return the vGPU only if it has time slice left */ |
| if (vgpu_data->left_ts > 0) { |
| vgpu = vgpu_data->vgpu; |
| break; |
| } |
| } |
| |
| return vgpu; |
| } |
| |
| /* in nanosecond */ |
| #define GVT_DEFAULT_TIME_SLICE 1000000 |
| |
| static void tbs_sched_func(struct gvt_sched_data *sched_data) |
| { |
| struct intel_gvt *gvt = sched_data->gvt; |
| struct intel_gvt_workload_scheduler *scheduler = &gvt->scheduler; |
| struct vgpu_sched_data *vgpu_data; |
| struct intel_vgpu *vgpu = NULL; |
| static uint64_t timer_check; |
| |
| if (!(timer_check++ % GVT_TS_BALANCE_PERIOD_MS)) |
| gvt_balance_timeslice(sched_data); |
| |
| /* no active vgpu or has already had a target */ |
| if (list_empty(&sched_data->lru_runq_head) || scheduler->next_vgpu) |
| goto out; |
| |
| vgpu = find_busy_vgpu(sched_data); |
| if (vgpu) { |
| scheduler->next_vgpu = vgpu; |
| |
| /* Move the last used vGPU to the tail of lru_list */ |
| vgpu_data = vgpu->sched_data; |
| list_del_init(&vgpu_data->lru_list); |
| list_add_tail(&vgpu_data->lru_list, |
| &sched_data->lru_runq_head); |
| } else { |
| scheduler->next_vgpu = gvt->idle_vgpu; |
| } |
| out: |
| if (scheduler->next_vgpu) |
| try_to_schedule_next_vgpu(gvt); |
| } |
| |
| void intel_gvt_schedule(struct intel_gvt *gvt) |
| { |
| struct gvt_sched_data *sched_data = gvt->scheduler.sched_data; |
| |
| mutex_lock(&gvt->lock); |
| tbs_sched_func(sched_data); |
| mutex_unlock(&gvt->lock); |
| } |
| |
| static enum hrtimer_restart tbs_timer_fn(struct hrtimer *timer_data) |
| { |
| struct gvt_sched_data *data; |
| |
| data = container_of(timer_data, struct gvt_sched_data, timer); |
| |
| intel_gvt_request_service(data->gvt, INTEL_GVT_REQUEST_SCHED); |
| |
| hrtimer_add_expires_ns(&data->timer, data->period); |
| |
| return HRTIMER_RESTART; |
| } |
| |
| static int tbs_sched_init(struct intel_gvt *gvt) |
| { |
| struct intel_gvt_workload_scheduler *scheduler = |
| &gvt->scheduler; |
| |
| struct gvt_sched_data *data; |
| |
| data = kzalloc(sizeof(*data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| INIT_LIST_HEAD(&data->lru_runq_head); |
| hrtimer_init(&data->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); |
| data->timer.function = tbs_timer_fn; |
| data->period = GVT_DEFAULT_TIME_SLICE; |
| data->gvt = gvt; |
| |
| scheduler->sched_data = data; |
| |
| return 0; |
| } |
| |
| static void tbs_sched_clean(struct intel_gvt *gvt) |
| { |
| struct intel_gvt_workload_scheduler *scheduler = |
| &gvt->scheduler; |
| struct gvt_sched_data *data = scheduler->sched_data; |
| |
| hrtimer_cancel(&data->timer); |
| |
| kfree(data); |
| scheduler->sched_data = NULL; |
| } |
| |
| static int tbs_sched_init_vgpu(struct intel_vgpu *vgpu) |
| { |
| struct vgpu_sched_data *data; |
| |
| data = kzalloc(sizeof(*data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| data->sched_ctl.weight = vgpu->sched_ctl.weight; |
| data->vgpu = vgpu; |
| INIT_LIST_HEAD(&data->lru_list); |
| |
| vgpu->sched_data = data; |
| |
| return 0; |
| } |
| |
| static void tbs_sched_clean_vgpu(struct intel_vgpu *vgpu) |
| { |
| kfree(vgpu->sched_data); |
| vgpu->sched_data = NULL; |
| } |
| |
| static void tbs_sched_start_schedule(struct intel_vgpu *vgpu) |
| { |
| struct gvt_sched_data *sched_data = vgpu->gvt->scheduler.sched_data; |
| struct vgpu_sched_data *vgpu_data = vgpu->sched_data; |
| |
| if (!list_empty(&vgpu_data->lru_list)) |
| return; |
| |
| list_add_tail(&vgpu_data->lru_list, &sched_data->lru_runq_head); |
| |
| if (!hrtimer_active(&sched_data->timer)) |
| hrtimer_start(&sched_data->timer, ktime_add_ns(ktime_get(), |
| sched_data->period), HRTIMER_MODE_ABS); |
| } |
| |
| static void tbs_sched_stop_schedule(struct intel_vgpu *vgpu) |
| { |
| struct vgpu_sched_data *vgpu_data = vgpu->sched_data; |
| |
| list_del_init(&vgpu_data->lru_list); |
| } |
| |
| static struct intel_gvt_sched_policy_ops tbs_schedule_ops = { |
| .init = tbs_sched_init, |
| .clean = tbs_sched_clean, |
| .init_vgpu = tbs_sched_init_vgpu, |
| .clean_vgpu = tbs_sched_clean_vgpu, |
| .start_schedule = tbs_sched_start_schedule, |
| .stop_schedule = tbs_sched_stop_schedule, |
| }; |
| |
| int intel_gvt_init_sched_policy(struct intel_gvt *gvt) |
| { |
| gvt->scheduler.sched_ops = &tbs_schedule_ops; |
| |
| return gvt->scheduler.sched_ops->init(gvt); |
| } |
| |
| void intel_gvt_clean_sched_policy(struct intel_gvt *gvt) |
| { |
| gvt->scheduler.sched_ops->clean(gvt); |
| } |
| |
| int intel_vgpu_init_sched_policy(struct intel_vgpu *vgpu) |
| { |
| return vgpu->gvt->scheduler.sched_ops->init_vgpu(vgpu); |
| } |
| |
| void intel_vgpu_clean_sched_policy(struct intel_vgpu *vgpu) |
| { |
| vgpu->gvt->scheduler.sched_ops->clean_vgpu(vgpu); |
| } |
| |
| void intel_vgpu_start_schedule(struct intel_vgpu *vgpu) |
| { |
| gvt_dbg_core("vgpu%d: start schedule\n", vgpu->id); |
| |
| vgpu->gvt->scheduler.sched_ops->start_schedule(vgpu); |
| } |
| |
| void intel_vgpu_stop_schedule(struct intel_vgpu *vgpu) |
| { |
| struct intel_gvt_workload_scheduler *scheduler = |
| &vgpu->gvt->scheduler; |
| |
| gvt_dbg_core("vgpu%d: stop schedule\n", vgpu->id); |
| |
| scheduler->sched_ops->stop_schedule(vgpu); |
| |
| if (scheduler->next_vgpu == vgpu) |
| scheduler->next_vgpu = NULL; |
| |
| if (scheduler->current_vgpu == vgpu) { |
| /* stop workload dispatching */ |
| scheduler->need_reschedule = true; |
| scheduler->current_vgpu = NULL; |
| } |
| } |