Change to internal v3_yield/yield_cond semantics:

[palacios.git] / palacios / src / palacios / vmm_time.c

diff --git a/palacios/src/palacios/vmm_time.c b/palacios/src/palacios/vmm_time.c
index ce89b21..3fb36ce 100644 (file)
--- a/palacios/src/palacios/vmm_time.c
+++ b/palacios/src/palacios/vmm_time.c
@@ -84,6 +84,16 @@ static int handle_cpufreq_hcall(struct guest_info * info, uint_t hcall_id, void
     return 0;
 }
 
+static int handle_rdhtsc_hcall(struct guest_info * info, uint_t hcall_id, void * priv_data) {
+    struct vm_core_time * time_state = &(info->time_state);
+
+    info->vm_regs.rbx = v3_get_host_time(time_state);
+
+    // PrintDebug("Guest request host TSC: return %ld\n", (long)info->vm_regs.rbx);
+    
+    return 0;
+}
+
 
 
 int v3_start_time(struct guest_info * info) {
@@ -97,7 +107,7 @@ int v3_start_time(struct guest_info * info) {
     info->time_state.guest_cycles = 0;
     PrintDebug("Starting time for core %d at host time %llu/guest time %llu.\n",
               info->vcpu_id, t, info->time_state.guest_cycles); 
-    v3_yield(info);
+    v3_yield(info,-1);
     return 0;
 }
 
@@ -152,6 +162,12 @@ struct v3_timer * v3_add_timer(struct guest_info * info,
                               void * private_data) {
     struct v3_timer * timer = NULL;
     timer = (struct v3_timer *)V3_Malloc(sizeof(struct v3_timer));
+
+    if (!timer) {
+       PrintError("Cannot allocate in adding a timer\n");
+       return NULL;
+    }
+
     V3_ASSERT(timer != NULL);
 
     timer->ops = ops;
@@ -314,7 +330,7 @@ static int tsc_msr_write_hook(struct guest_info *info, uint_t msr_num,
 
 static int
 handle_time_configuration(struct v3_vm_info * vm, v3_cfg_tree_t *cfg) {
-    char *source, *dilation;
+    char *source, *dilation, *tsc;
 
     vm->time_state.flags = V3_TIME_SLAVE_HOST;
     vm->time_state.td_num = vm->time_state.td_denom = 1;
@@ -332,6 +348,19 @@ handle_time_configuration(struct v3_vm_info * vm, v3_cfg_tree_t *cfg) {
        }
     }
 
+    // Should we make a separate TSC device that handles this sort of thing?
+    tsc = v3_cfg_val(cfg, "tsc");
+    if (tsc) {
+       if (strcasecmp(tsc, "host") == 0) {
+           if (!(vm->time_state.flags & V3_TIME_SLAVE_HOST)) {
+               PrintError("WARNING: Guest TSC set to passthrough host TSC, but guest time not slaved to host time.");
+           }
+           vm->time_state.flags |= V3_TIME_TSC_PASSTHROUGH;
+       } else if (strcasecmp(source, "guest") != 0) {
+           PrintError("ERROR: Unknown TSC configuration in time configuration.\n");
+       }
+    }
+
     dilation = v3_cfg_val(cfg, "dilation");
     if (dilation) {
         if (!(vm->time_state.flags & VM_TIME_SLAVE_HOST)) {
@@ -380,6 +409,9 @@ int v3_init_time_vm(struct v3_vm_info * vm) {
     PrintDebug("Registering TIME_CPUFREQ hypercall.\n");
     ret = v3_register_hypercall(vm, TIME_CPUFREQ_HCALL, 
                                handle_cpufreq_hcall, NULL);
+    PrintDebug("Registering TIME_RDHTSC hypercall.\n");
+    ret = v3_register_hypercall(vm, TIME_RDHTSC_HCALL, 
+                               handle_rdhtsc_hcall, NULL);
 
     handle_time_configuration(vm, v3_cfg_subtree(cfg_tree, "time"));
 
@@ -450,10 +482,18 @@ void v3_init_time_core(struct guest_info * info) {
     if (info->vm_info->time_state.flags & V3_TIME_SLAVE_HOST) {
        time_state->flags |= VM_TIME_SLAVE_HOST;
     }
+    if (info->vm_info->time_state.flags & V3_TIME_TSC_PASSTHROUGH) {
+       time_state->flags |= VM_TIME_TSC_PASSTHROUGH;
+    }
+
     if ((time_state->clock_ratio_denom != 1) ||
        (time_state->clock_ratio_num != 1) ||
        (info->vm_info->time_state.td_num != 1) || 
        (info->vm_info->time_state.td_denom != 1)) { 
+       if (time_state->flags | VM_TIME_TSC_PASSTHROUGH) {
+           PrintError("WARNING: Cannot use reqested passthrough TSC with clock or time modification also requested.\n");
+           time_state->flags &= ~VM_TIME_TSC_PASSTHROUGH;
+       }
        time_state->flags |= VM_TIME_TRAP_RDTSC;
     }
 
@@ -466,9 +506,11 @@ void v3_init_time_core(struct guest_info * info) {
               info->vm_info->time_state.td_denom, 
               time_state->clock_ratio_num, time_state->clock_ratio_denom,
               time_state->ipc_ratio_num, time_state->ipc_ratio_denom);
-    PrintDebug("    source = %s, rdtsc trapping = %s\n", 
+    PrintDebug("    time source = %s, tsc handling =  %s\n", 
               (time_state->flags & VM_TIME_SLAVE_HOST) ? "host" : "none",
-              (time_state->flags & VM_TIME_TRAP_RDTSC) ? "true" : "false");
+              (time_state->flags & VM_TIME_TSC_PASSTHROUGH) ? "passthrough" 
+                  : (time_state->flags & VM_TIME_TRAP_RDTSC) ? "trapping" 
+                      : "offsettting");
 
     time_state->guest_cycles = 0;
     time_state->tsc_guest_offset = 0;