From: Peter Dinda <pdinda@northwestern.edu>
Date: Sat, 7 Jul 2012 23:23:23 +0000 (-0500)
Subject: Change to internal v3_yield/yield_cond semantics:
X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=commitdiff_plain;h=25aec1d035e5a740d8c1cb936d7633b6bb5751f1;p=palacios.git

Change to internal v3_yield/yield_cond semantics:

v3_yield(guest, time (usec) )

time <   0 => direct call to host yield os hook
time >=0 0 => direct call to host yield_timed os hook
              (this usually implies interruptible, even if time=0)

time is in usec
---

diff --git a/palacios/include/palacios/vmm.h b/palacios/include/palacios/vmm.h
index df66aeb..0c10e84 100644
--- a/palacios/include/palacios/vmm.h
+++ b/palacios/include/palacios/vmm.h
@@ -275,9 +275,8 @@ typedef enum v3_cpu_arch {V3_INVALID_CPU, V3_SVM_CPU, V3_SVM_REV3_CPU, V3_VMX_CP
 
 v3_cpu_mode_t v3_get_host_cpu_mode();
 
-void v3_yield(struct guest_info * info);
-void v3_yield_cond(struct guest_info * info);
-void v3_yield_timed(struct guest_info * info, unsigned int usec);
+void v3_yield(struct guest_info * info, int usec);
+void v3_yield_cond(struct guest_info * info, int usec);
 void v3_print_cond(const char * fmt, ...);
 
 void v3_interrupt_cpu(struct v3_vm_info * vm, int logical_cpu, int vector);
diff --git a/palacios/src/palacios/svm.c b/palacios/src/palacios/svm.c
index facdb18..8a1b3e4 100644
--- a/palacios/src/palacios/svm.c
+++ b/palacios/src/palacios/svm.c
@@ -564,7 +564,7 @@ int v3_svm_enter(struct guest_info * info) {
     uint64_t guest_cycles = 0;
 
     // Conditionally yield the CPU if the timeslice has expired
-    v3_yield_cond(info);
+    v3_yield_cond(info,-1);
 
     // Update timer devices after being in the VM before doing 
     // IRQ updates, so that any interrupts they raise get seen 
@@ -695,7 +695,7 @@ int v3_svm_enter(struct guest_info * info) {
     v3_stgi();
  
     // Conditionally yield the CPU if the timeslice has expired
-    v3_yield_cond(info);
+    v3_yield_cond(info,-1);
 
     // This update timers is for time-dependent handlers
     // if we're slaved to host time
@@ -740,7 +740,7 @@ int v3_start_svm_guest(struct guest_info * info) {
 		return 0;
 	    }
 
-	    v3_yield(info);
+	    v3_yield(info,-1);
 	    //PrintDebug("SVM core %u: still waiting for INIT\n", info->vcpu_id);
 	}
 
diff --git a/palacios/src/palacios/vmm.c b/palacios/src/palacios/vmm.c
index 30fa2e6..21ca408 100644
--- a/palacios/src/palacios/vmm.c
+++ b/palacios/src/palacios/vmm.c
@@ -482,7 +482,7 @@ int v3_stop_vm(struct v3_vm_info * vm) {
  	    break;
 	}
 
-	v3_yield(NULL);
+	v3_yield(NULL,-1);
     }
     
     V3_Print("VM stopped. Returning\n");
@@ -530,7 +530,7 @@ static int sim_callback(struct guest_info * core, void * private_data) {
     V3_Print("Simulation callback activated (guest_rip=%p)\n", (void *)core->rip);
 
     while (v3_bitmap_check(timeout_map, core->vcpu_id) == 1) {
-	v3_yield(NULL);
+	v3_yield(NULL,-1);
     }
 
     return 0;
@@ -601,7 +601,7 @@ int v3_simulate_vm(struct v3_vm_info * vm, unsigned int msecs) {
 	    break;
 	}
 
-	v3_yield(NULL);
+	v3_yield(NULL,-1);
     }
 
 
@@ -690,7 +690,7 @@ v3_cpu_mode_t v3_get_host_cpu_mode() {
 
 
 
-void v3_yield_cond(struct guest_info * info) {
+void v3_yield_cond(struct guest_info * info, int usec) {
     uint64_t cur_cycle;
     cur_cycle = v3_get_host_time(&info->time_state);
 
@@ -699,7 +699,12 @@ void v3_yield_cond(struct guest_info * info) {
 	//           (void *)cur_cycle, (void *)info->yield_start_cycle, 
 	//	   (void *)info->yield_cycle_period);
 	
-	V3_Yield();
+	if (usec < 0) { 
+	    V3_Yield();
+	} else {
+	    V3_Yield_Timed(usec);
+	}
+
         info->yield_start_cycle +=  info->vm_info->yield_cycle_period;
     }
 }
@@ -709,9 +714,16 @@ void v3_yield_cond(struct guest_info * info) {
  * unconditional cpu yield 
  * if the yielding thread is a guest context, the guest quantum is reset on resumption 
  * Non guest context threads should call this function with a NULL argument
- */
-void v3_yield(struct guest_info * info) {
-    V3_Yield();
+ *
+ * usec <0  => the non-timed yield is used
+ * usec >=0 => the timed yield is used, which also usually implies interruptible
+ */ 
+void v3_yield(struct guest_info * info, int usec) {
+    if (usec < 0) { 
+	V3_Yield();
+    } else {
+	V3_Yield_Timed(usec);
+    }
 
     if (info) {
         info->yield_start_cycle +=  info->vm_info->yield_cycle_period;
@@ -719,18 +731,6 @@ void v3_yield(struct guest_info * info) {
 }
 
 
-/*
- * unconditional cpu yield for a period of time
- * Otherwise identical to v3_yield
- */
-void v3_yield_timed(struct guest_info *info, unsigned int usec)
-{
-    V3_Yield_Timed(usec);
-    
-    if (info) { 
-	info->yield_start_cycle += info->vm_info->yield_cycle_period;
-    }
-}
 
 
 void v3_print_cond(const char * fmt, ...) {
diff --git a/palacios/src/palacios/vmm_barrier.c b/palacios/src/palacios/vmm_barrier.c
index 961b894..e6f1221 100644
--- a/palacios/src/palacios/vmm_barrier.c
+++ b/palacios/src/palacios/vmm_barrier.c
@@ -120,7 +120,7 @@ int v3_wait_for_barrier(struct v3_vm_info * vm_info, struct guest_info * local_c
 	    break;
 	}
 
-	v3_yield(local_core);
+	v3_yield(local_core,-1);
     }
 
     return 0;
@@ -199,7 +199,7 @@ int v3_wait_at_barrier(struct guest_info * core) {
 
     // wait for cpu bit to clear
     while (v3_bitmap_check(&(barrier->cpu_map), core->vcpu_id)) {
-	v3_yield(core);
+	v3_yield(core,-1);
     }
 
     return 0;
diff --git a/palacios/src/palacios/vmm_halt.c b/palacios/src/palacios/vmm_halt.c
index 60ca74b..e7862c8 100644
--- a/palacios/src/palacios/vmm_halt.c
+++ b/palacios/src/palacios/vmm_halt.c
@@ -46,7 +46,7 @@ int v3_handle_halt(struct guest_info * info) {
             uint64_t t, cycles;
 	    /* Yield, allowing time to pass while yielded */
 	    t = v3_get_host_time(&info->time_state);
-	    v3_yield_timed(info,YIELD_TIME_USEC);
+	    v3_yield(info,YIELD_TIME_USEC);
 	    cycles = v3_get_host_time(&info->time_state) - t;
 	    v3_advance_time(info, &cycles);
 
diff --git a/palacios/src/palacios/vmm_time.c b/palacios/src/palacios/vmm_time.c
index d9ca1d6..3fb36ce 100644
--- a/palacios/src/palacios/vmm_time.c
+++ b/palacios/src/palacios/vmm_time.c
@@ -107,7 +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;
 }
 
diff --git a/palacios/src/palacios/vmx.c b/palacios/src/palacios/vmx.c
index a80b8f2..ed5140f 100644
--- a/palacios/src/palacios/vmx.c
+++ b/palacios/src/palacios/vmx.c
@@ -948,7 +948,7 @@ int v3_vmx_enter(struct guest_info * info) {
     uint64_t guest_cycles = 0;
 
     // Conditionally yield the CPU if the timeslice has expired
-    v3_yield_cond(info);
+    v3_yield_cond(info,-1);
 
     // Update timer devices late after being in the VM so that as much 
     // of the time in the VM is accounted for as possible. Also do it before
@@ -1105,7 +1105,7 @@ int v3_vmx_enter(struct guest_info * info) {
     v3_enable_ints();
 
     // Conditionally yield the CPU if the timeslice has expired
-    v3_yield_cond(info);
+    v3_yield_cond(info,-1);
     v3_advance_time(info, NULL);
     v3_update_timers(info);
 
@@ -1140,7 +1140,7 @@ int v3_start_vmx_guest(struct guest_info * info) {
 		return 0;
 	    }
 
-            v3_yield(info);
+            v3_yield(info,-1);
             //PrintDebug("VMX core %u: still waiting for INIT\n",info->vcpu_id);
         }