X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_barrier.c;h=a94e40f157eb5d82c2b370886ce2022eb2d73d85;hb=4e43946f01f687361197dc9571b7df02ae20de30;hp=e6f12217124aeb525bb2588ff5ea51af220bc23e;hpb=25aec1d035e5a740d8c1cb936d7633b6bb5751f1;p=palacios.git

diff --git a/palacios/src/palacios/vmm_barrier.c b/palacios/src/palacios/vmm_barrier.c
index e6f1221..a94e40f 100644
--- a/palacios/src/palacios/vmm_barrier.c
+++ b/palacios/src/palacios/vmm_barrier.c
@@ -120,6 +120,7 @@ int v3_wait_for_barrier(struct v3_vm_info * vm_info, struct guest_info * local_c
 	    break;
 	}
 
+        // return immediately and spin if there is no one to yield to 
 	v3_yield(local_core,-1);
     }
 
@@ -141,6 +142,12 @@ int v3_wait_for_barrier(struct v3_vm_info * vm_info, struct guest_info * local_c
 int v3_raise_barrier(struct v3_vm_info * vm_info, struct guest_info * local_core) {
     int ret = 0;
 
+
+    if ((vm_info->run_state != VM_RUNNING) && 
+	(vm_info->run_state != VM_SIMULATING)) {
+	return 0;
+    }
+
     ret = v3_raise_barrier_nowait(vm_info, local_core);
 
     if (ret != 0) {
@@ -162,6 +169,12 @@ int v3_raise_barrier(struct v3_vm_info * vm_info, struct guest_info * local_core
 int v3_lower_barrier(struct v3_vm_info * vm_info) {
     struct v3_barrier * barrier = &(vm_info->barrier);
 
+    
+    if ((vm_info->run_state != VM_RUNNING) && 
+	(vm_info->run_state != VM_SIMULATING)) {
+	return 0;
+    }
+
     // Clear the active flag, so cores won't wait 
     barrier->active = 0;
 
@@ -185,8 +198,15 @@ int v3_wait_at_barrier(struct guest_info * core) {
     if (barrier->active == 0) {
 	return 0;
     }
+#ifndef V3_CONFIG_FP_SWITCH
+    v3_get_fp_state(core); // snapshot FP state now
+#else
+#   ifdef V3_CONFIG_LAZY_FP_SWITCH
+    v3_get_fp_state(core); // snapshot FP state now regardless of lazy eval
+#   endif
+#endif
 
-    V3_Print("Core %d waiting at barrier\n", core->vcpu_id);
+    V3_Print(core->vm_info, core, "Core %d waiting at barrier\n", core->vcpu_id);
 
     /*  Barrier has been activated. 
      *  Wait here until it's lowered
@@ -195,12 +215,21 @@ int v3_wait_at_barrier(struct guest_info * core) {
     
     // set cpu bit in barrier bitmap
     v3_bitmap_set(&(barrier->cpu_map), core->vcpu_id);
-    V3_Print("Core %d bit set as waiting\n", core->vcpu_id);
+    V3_Print(core->vm_info, core, "Core %d bit set as waiting\n", core->vcpu_id);
 
     // wait for cpu bit to clear
     while (v3_bitmap_check(&(barrier->cpu_map), core->vcpu_id)) {
+        // Barrier wait will spin if there is no competing work
 	v3_yield(core,-1);
     }
 
+#ifndef V3_CONFIG_FP_SWITCH    
+    core->fp_state.need_restore=1;  // restore FP on next entry
+#else
+#   ifdef V3_CONFIG_LAZY_FP_SWITCH
+    core->fp_state.need_restore=1;  // restore FP on next entry
+#   endif
+#endif
+
     return 0;
 }