Palacios Public Git Repository

To checkout Palacios execute

  git clone http://v3vee.org/palacios/palacios.web/palacios.git
This will give you the master branch. You probably want the devel branch or one of the release branches. To switch to the devel branch, simply execute
  cd palacios
  git checkout --track -b devel origin/devel
The other branches are similar.


don't allow launch of an already running VM
[palacios.git] / palacios / src / palacios / vmm_time.c
index 67cdee9..7cf7853 100644 (file)
@@ -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) {
@@ -129,14 +139,14 @@ int v3_advance_time(struct guest_info * info, uint64_t *host_cycles)
 {
     uint64_t guest_cycles;
 
-    if (info->flags & VM_TIME_SLAVE_HOST) {
+    if (info->time_state.flags & VM_TIME_SLAVE_HOST) {
        struct v3_time *vm_ts = &(info->vm_info->time_state);
         uint64_t ht = v3_get_host_time(&info->time_state);
         uint64_t host_elapsed = ht - info->time_state.initial_host_time;
        uint64_t dilated_elapsed = (host_elapsed * vm_ts->td_num) / vm_ts->td_denom;
        uint64_t guest_elapsed = host_to_guest_cycles(info, dilated_elapsed);
        guest_cycles = guest_elapsed - v3_get_guest_time(&info->time_state);
-    } else if (*host_cycles) {
+    } else if (host_cycles) {
        guest_cycles = host_to_guest_cycles(info, *host_cycles);
     } else {
        guest_cycles = 0;
@@ -211,6 +221,7 @@ int v3_rdtsc(struct guest_info * info) {
 }
 
 int v3_handle_rdtsc(struct guest_info * info) {
+    PrintDebug("Handling virtual RDTSC call.\n");
     v3_rdtsc(info);
     
     info->vm_regs.rax &= 0x00000000ffffffffLL;
@@ -246,7 +257,7 @@ int v3_rdtscp(struct guest_info * info) {
 
 
 int v3_handle_rdtscp(struct guest_info * info) {
-  PrintDebug("Handling virtual RDTSCP call.\n");
+    PrintDebug("Handling virtual RDTSCP call.\n");
 
     v3_rdtscp(info);
 
@@ -287,6 +298,7 @@ static int tsc_msr_read_hook(struct guest_info *info, uint_t msr_num,
                             struct v3_msr *msr_val, void *priv) {
     uint64_t time = v3_get_guest_tsc(&info->time_state);
 
+    PrintDebug("Handling virtual TSC MSR read call.\n");
     V3_ASSERT(msr_num == TSC_MSR);
 
     msr_val->hi = time >> 32;
@@ -300,6 +312,7 @@ static int tsc_msr_write_hook(struct guest_info *info, uint_t msr_num,
     struct vm_core_time * time_state = &(info->time_state);
     uint64_t guest_time, new_tsc;
 
+    PrintDebug("Handling virtual TSC MSR write call.\n");
     V3_ASSERT(msr_num == TSC_MSR);
 
     new_tsc = (((uint64_t)msr_val.hi) << 32) | (uint64_t)msr_val.lo;
@@ -311,48 +324,57 @@ 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) {
-    v3_cfg_tree_t * slave;
+    char *source, *dilation, *tsc;
 
-    vm->time_state.flags = 0;
+    vm->time_state.flags = V3_TIME_SLAVE_HOST;
     vm->time_state.td_num = vm->time_state.td_denom = 1;
 
     if (!cfg) return 0;
 
-    slave = v3_cfg_subtree(cfg, "slave");
-    
-    if (slave) {
-        char *source = v3_cfg_val(slave, "source");
-       v3_cfg_tree_t *dilation = v3_cfg_subtree(slave, "dilation");
-       if (source) {
-           if (strcasecmp(source, "host")  == 0) {
-               PrintDebug("Slaving VM guest time to host time.\n");
-               vm->time_state.flags |= V3_TIME_SLAVE_HOST;
-           } else { 
-               PrintError("Unknown time source for slaving.\n");
+    source = v3_cfg_val(cfg, "source");
+    if (source) {
+       if (strcasecmp(source, "none") == 0) {
+           vm->time_state.flags &= ~V3_TIME_SLAVE_HOST;
+       } else if (strcasecmp(source, "host") != 0) {
+           PrintError("Unknown time source for VM core time management.\n");
+       } else {
+           PrintDebug("VM time slaved to host TSC.\n");
+       }
+    }
+
+    // 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.");
            }
-       } 
-        if (dilation && (vm->time_state.flags & V3_TIME_SLAVE_HOST)) {
-           char *str1, *str2;
+           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)) {
+           PrintError("Time dilation only valid when slaved to host time.\n");
+       } else {
            uint32_t num = 1, denom = 1;
-           if ((str1 = v3_cfg_val(dilation, "value"))) {
-               denom = atoi(str1);
-           } else if ((str1 = v3_cfg_val(dilation, "num"))
-                      && (str2 = v3_cfg_val(dilation, "denom"))) {
-               num = atoi(str1);
-               denom = atoi(str2);
-           }
+           denom = atoi(dilation);
            if ((num > 0) && (denom > 0)) {
                vm->time_state.td_num = num;
                vm->time_state.td_denom = denom;
            }
-           if ((vm->time_state.td_num != 1) 
-               || (vm->time_state.td_denom != 1)) {
-               V3_Print("Time dilated from host time by a factor of %d/%d"
-                        " in guest.\n", denom, num);
-           } else {
-               PrintError("Time dilation specifier in configuration did not"
-                          " result in actual time dilation in VM.\n");
-           }
+       }
+       if ((vm->time_state.td_num != 1) 
+           || (vm->time_state.td_denom != 1)) {
+           V3_Print("Time dilated from host time by a factor of %d/%d"
+                    " in guest.\n", vm->time_state.td_denom, 
+                    vm->time_state.td_num);
+       } else {
+           PrintError("Time dilation specifier in configuration did not"
+                      " result in actual time dilation in VM.\n");
        }
     }
     return 0;
@@ -381,6 +403,9 @@ 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"));
 
@@ -397,11 +422,11 @@ void v3_deinit_time_vm(struct v3_vm_info * vm) {
 static uint32_t
 gcd ( uint32_t a, uint32_t b )
 {
-  uint32_t c;
-  while ( a != 0 ) {
-     c = a; a = b%a;  b = c;
-  }
-  return b;
+    uint32_t c;
+    while ( a != 0 ) {
+        c = a; a = b%a;  b = c;
+    }
+    return b;
 }
 
 static int compute_core_ratios(struct guest_info * info, 
@@ -414,7 +439,7 @@ static int compute_core_ratios(struct guest_info * info,
      * If the GCD is too small, make it "big enough" */
     khzGCD = gcd(hostKhz, guestKhz);
     if (khzGCD < 1024)
-       khzGCD = 1000;
+       khzGCD = 1024;
 
     time_state->clock_ratio_num = guestKhz / khzGCD;
     time_state->clock_ratio_denom = hostKhz / khzGCD;
@@ -440,42 +465,55 @@ void v3_init_time_core(struct guest_info * info) {
     } 
     
     if ( (khz == NULL) || 
-        (time_state->guest_cpu_freq <= 0)  || 
-        (time_state->guest_cpu_freq > time_state->host_cpu_freq) ) {
-
+        (time_state->guest_cpu_freq <= 0)) {
+/*  || (time_state->guest_cpu_freq > time_state->host_cpu_freq) ) { */
        time_state->guest_cpu_freq = time_state->host_cpu_freq;
     }
+    compute_core_ratios(info, time_state->host_cpu_freq, 
+                       time_state->guest_cpu_freq);
+    
+    time_state->flags = 0;
+    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;
+    }
+
     PrintDebug("Logical Core %d (vcpu=%d) CPU frequency set to %d KHz (host CPU frequency = %d KHz).\n", 
               info->pcpu_id, info->vcpu_id,
               time_state->guest_cpu_freq, 
               time_state->host_cpu_freq);
-
-    compute_core_ratios(info, time_state->host_cpu_freq, 
-                       time_state->guest_cpu_freq);
-    
     PrintDebug("    td_mult = %d/%d, cl_mult = %u/%u, ipc_mult = %u/%u.\n",
               info->vm_info->time_state.td_num, 
               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("    time source = %s, tsc handling =  %s\n", 
+              (time_state->flags & VM_TIME_SLAVE_HOST) ? "host" : "none",
+              (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;
     time_state->last_update = 0;
-
     time_state->initial_host_time = 0;
 
-    time_state->flags = 0;
-    if (info->vm_info->time_state.flags & V3_TIME_SLAVE_HOST) {
-        time_state->flags |= VM_TIME_SLAVE_HOST;
-    }
-    if ((time_state->clock_ratio_denom != 1) ||
-       (time_state->clock_ratio_num != 1)) {
-        time_state->flags |= VM_TIME_TRAP_RDTSC;
-    }
-
     INIT_LIST_HEAD(&(time_state->timers));
     time_state->num_timers = 0;
-    
+           
     time_state->tsc_aux.lo = 0;
     time_state->tsc_aux.hi = 0;
 }
@@ -489,5 +527,4 @@ void v3_deinit_time_core(struct guest_info * core) {
     list_for_each_entry_safe(tmr, tmp, &(time_state->timers), timer_link) {
        v3_remove_timer(core, tmr);
     }
-
 }