X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_time.c;h=7cf7853cd4ff97a10a2e6c1ba9b82e9e1f8e3d88;hb=1c000bda0560742ad6be011722fa226771b656ff;hp=491ceabae4b763db1493c918c3db10e64531d96c;hpb=b114cb5ecaeb5e330511684a1c8d56e23fb2f136;p=palacios.git

diff --git a/palacios/src/palacios/vmm_time.c b/palacios/src/palacios/vmm_time.c
index 491ceab..7cf7853 100644
--- 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) {
@@ -129,7 +139,7 @@ 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;
@@ -314,7 +324,7 @@ 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 +342,19 @@ 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 +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"));
 
@@ -450,8 +476,18 @@ 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)) {
+	(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;
     }
 
@@ -464,9 +500,11 @@ 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;