2 * This file is part of the Palacios Virtual Machine Monitor developed
3 * by the V3VEE Project with funding from the United States National
4 * Science Foundation and the Department of Energy.
6 * The V3VEE Project is a joint project between Northwestern University
7 * and the University of New Mexico. You can find out more at
10 * Copyright (c) 2013, Oscar Mondragon <omondrag@cs.unm.edu>
11 * Copyright (c) 2013, Patrick G. Bridges <bridges@cs.unm.edu>
12 * Copyright (c) 2013, The V3VEE Project <http://www.v3vee.org>
13 * All rights reserved.
15 * Author: Oscar Mondragon <omondrag@cs.unm.edu>
16 * Patrick G. Bridges <bridges@cs.unm.edu>
18 * This is free software. You are permitted to use,
19 * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
22 #include <palacios/vmm.h>
23 #include <palacios/vm_guest.h>
24 #include <palacios/vmm_scheduler.h>
25 #include <palacios/vmm_hashtable.h>
27 #ifndef V3_CONFIG_DEBUG_SCHEDULER
29 #define PrintDebug(fmt, args...)
32 static char default_strategy[] = "host";
33 static struct hashtable * master_scheduler_table = NULL;
34 static int create_host_scheduler();
35 static int destroy_host_scheduler();
37 static struct vm_scheduler_impl *scheduler = NULL;
39 static uint_t scheduler_hash_fn(addr_t key) {
40 char * name = (char *)key;
41 return v3_hash_buffer((uint8_t *)name, strlen(name));
44 static int scheduler_eq_fn(addr_t key1, addr_t key2) {
45 char * name1 = (char *)key1;
46 char * name2 = (char *)key2;
48 return (strcmp(name1, name2) == 0);
51 int V3_init_scheduling() {
53 PrintDebug(VM_NONE, VCORE_NONE,"Initializing scheduler");
55 master_scheduler_table = v3_create_htable(0, scheduler_hash_fn, scheduler_eq_fn);
56 return create_host_scheduler();
59 int V3_deinit_scheduling()
61 destroy_host_scheduler();
62 v3_free_htable(master_scheduler_table,1,1);
67 int v3_register_scheduler(struct vm_scheduler_impl *s) {
69 PrintDebug(VM_NONE, VCORE_NONE,"Registering Scheduler (%s)\n", s->name);
71 if (v3_htable_search(master_scheduler_table, (addr_t)(s->name))) {
72 PrintError(VM_NONE, VCORE_NONE, "Multiple instances of scheduler (%s)\n", s->name);
76 if (v3_htable_insert(master_scheduler_table,
79 PrintError(VM_NONE, VCORE_NONE, "Could not register scheduler (%s)\n", s->name);
87 struct vm_scheduler_impl *v3_unregister_scheduler(char *name) {
89 PrintDebug(VM_NONE, VCORE_NONE,"Unregistering Scheduler (%s)\n",name);
91 struct vm_scheduler_impl *f = (struct vm_scheduler_impl *) v3_htable_remove(master_scheduler_table,(addr_t)(name),0);
94 PrintError(VM_NONE,VCORE_NONE,"Could not find Scheduler (%s)\n",name);
104 struct vm_scheduler_impl *v3_scheduler_lookup(char *name)
106 return (struct vm_scheduler_impl *)v3_htable_search(master_scheduler_table, (addr_t)(name));
109 int V3_enable_scheduler() {
113 sched_name = v3_lookup_option("scheduler");
116 scheduler = v3_scheduler_lookup(sched_name);
120 scheduler = v3_scheduler_lookup(default_strategy);
124 PrintError(VM_NONE, VCORE_NONE,"Specified Palacios scheduler \"%s\" not found.\n", default_strategy);
128 PrintDebug(VM_NONE, VCORE_NONE,"Scheduler %s found",scheduler->name);
130 if (scheduler->init) {
131 return scheduler->init();
137 int V3_disable_scheduler()
139 if (scheduler->deinit) {
140 return scheduler->deinit();
146 int v3_scheduler_register_vm(struct v3_vm_info *vm) {
147 if (scheduler->vm_init) {
148 return scheduler->vm_init(vm);
153 int v3_scheduler_register_core(struct guest_info *core) {
154 if (scheduler->core_init) {
155 return scheduler->core_init(core);
160 int v3_scheduler_admit_vm(struct v3_vm_info *vm) {
161 if (scheduler->admit) {
162 return scheduler->admit(vm);
167 int v3_scheduler_notify_remap(struct v3_vm_info *vm) {
168 if (scheduler->remap) {
169 return scheduler->remap(vm);
174 int v3_scheduler_notify_dvfs(struct v3_vm_info *vm) {
175 if (scheduler->dvfs) {
176 return scheduler->dvfs(vm);
181 void v3_schedule(struct guest_info *core) {
182 if (scheduler->schedule) {
183 scheduler->schedule(core);
187 void v3_yield(struct guest_info *core, int usec) {
188 if (scheduler->yield) {
189 scheduler->yield(core, usec);
194 int host_sched_vm_init(struct v3_vm_info *vm)
197 PrintDebug(vm, VCORE_NONE,"Sched. host_sched_init\n");
199 char * schedule_hz_str = v3_cfg_val(vm->cfg_data->cfg, "schedule_hz");
200 uint32_t sched_hz = 100;
203 if (schedule_hz_str) {
204 sched_hz = atoi(schedule_hz_str);
207 PrintDebug(vm, VCORE_NONE,"CPU_KHZ = %d, schedule_freq=%p\n", V3_CPU_KHZ(),
208 (void *)(addr_t)sched_hz);
210 uint64_t yield_cycle_period = (V3_CPU_KHZ() * 1000) / sched_hz;
211 vm->sched_priv_data = (void *)yield_cycle_period;
216 int host_sched_core_init(struct guest_info *core)
218 PrintDebug(core->vm_info, core,"Sched. host_sched_core_init\n");
220 uint64_t t = v3_get_host_time(&core->time_state);
221 core->sched_priv_data = (void *)t;
226 void host_sched_schedule(struct guest_info *core)
229 cur_cycle = v3_get_host_time(&core->time_state);
231 if (cur_cycle > ( (uint64_t)core->sched_priv_data + (uint64_t)core->vm_info->sched_priv_data)) {
235 core->sched_priv_data = (void*)v3_get_host_time(&(core->time_state));
241 * unconditional cpu yield
242 * if the yielding thread is a guest context, the guest quantum is reset on resumption
243 * Non guest context threads should call this function with a NULL argument
245 * usec <0 => the non-timed yield is used
246 * usec >=0 => the timed yield is used, which also usually implies interruptible
248 void host_sched_yield(struct guest_info * core, int usec) {
256 core->sched_priv_data = (void*)v3_get_host_time(&(core->time_state));
261 int host_sched_admit(struct v3_vm_info *vm){
265 static struct vm_scheduler_impl host_sched_impl = {
269 .vm_init = host_sched_vm_init,
271 .core_init = host_sched_core_init,
273 .schedule = host_sched_schedule,
274 .yield = host_sched_yield,
275 .admit = host_sched_admit,
280 static int create_host_scheduler()
282 v3_register_scheduler(&host_sched_impl);
286 static int destroy_host_scheduler()
288 v3_unregister_scheduler(host_sched_impl.name);