minor changes to yields to avoid guest lock ups due to irq flooding scenarios

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

diff --git a/palacios/src/palacios/vmm_intr.c b/palacios/src/palacios/vmm_intr.c
index e29285a..b65dfef 100644 (file)
--- a/palacios/src/palacios/vmm_intr.c
+++ b/palacios/src/palacios/vmm_intr.c
@@ -24,6 +24,8 @@
 #include <palacios/vm_guest.h>
 #include <palacios/vmm_ctrl_regs.h>
 
+#include <palacios/vmm_lock.h>
+
 #ifndef DEBUG_INTERRUPTS
 #undef PrintDebug
 #define PrintDebug(fmt, args...)
@@ -34,7 +36,7 @@
 
 struct intr_controller {
     struct intr_ctrl_ops * ctrl_ops;
-
+    
     void * priv_data;
     struct list_head ctrl_node;
 };
@@ -43,10 +45,13 @@ struct intr_controller {
 void v3_init_interrupt_state(struct guest_info * info) {
 
     info->intr_state.irq_pending = 0;
+    info->intr_state.irq_started = 0;
     info->intr_state.irq_vector = 0;
 
     INIT_LIST_HEAD(&(info->intr_state.controller_list));
 
+    v3_lock_init(&(info->intr_state.irq_lock));
+
     memset((uchar_t *)(info->intr_state.hooks), 0, sizeof(struct v3_irq_hook *) * 256);
 }
 
@@ -150,11 +155,14 @@ int v3_lower_irq(struct guest_info * info, int irq) {
     struct v3_intr_state * intr_state = &(info->intr_state);
 
     //    PrintDebug("[v3_lower_irq]\n");
+    addr_t irq_state = v3_lock_irqsave(intr_state->irq_lock);
 
     list_for_each_entry(ctrl, &(intr_state->controller_list), ctrl_node) {
        ctrl->ctrl_ops->lower_intr(ctrl->priv_data, irq);
     }
  
+    v3_unlock_irqrestore(intr_state->irq_lock, irq_state);
+
     return 0;
 }
 
@@ -163,11 +171,14 @@ int v3_raise_irq(struct guest_info * info, int irq) {
     struct v3_intr_state * intr_state = &(info->intr_state);
 
     //  PrintDebug("[v3_raise_irq (%d)]\n", irq);
+    addr_t irq_state = v3_lock_irqsave(intr_state->irq_lock);
 
     list_for_each_entry(ctrl, &(intr_state->controller_list), ctrl_node) {
        ctrl->ctrl_ops->raise_intr(ctrl->priv_data, irq);
     }
 
+    v3_unlock_irqrestore(intr_state->irq_lock, irq_state);
+
     return 0;
 }
 
@@ -176,55 +187,72 @@ int v3_raise_irq(struct guest_info * info, int irq) {
 int v3_intr_pending(struct guest_info * info) {
     struct v3_intr_state * intr_state = &(info->intr_state);
     struct intr_controller * ctrl = NULL;
-    struct rflags * flags = (struct rflags *)&(info->ctrl_regs.rflags);
+    int ret = 0;
+
     //  PrintDebug("[intr_pending]\n");
-    
-    // Check if the guest has interrupts enabled
-    if (flags->intr == 0) {
-       return 0;
-    }
+    addr_t irq_state = v3_lock_irqsave(intr_state->irq_lock);    
 
     list_for_each_entry(ctrl, &(intr_state->controller_list), ctrl_node) {
        if (ctrl->ctrl_ops->intr_pending(ctrl->priv_data) == 1) {
-           return 1;
+           ret = 1;
+           break;
        }
     }
 
+    v3_unlock_irqrestore(intr_state->irq_lock, irq_state);
 
-    return 0;
+    return ret;
 }
 
 
 uint_t v3_get_intr_number(struct guest_info * info) {
     struct v3_intr_state * intr_state = &(info->intr_state);
     struct intr_controller * ctrl = NULL;
+    uint_t ret = 0;
+
+    addr_t irq_state = v3_lock_irqsave(intr_state->irq_lock);    
 
     list_for_each_entry(ctrl, &(intr_state->controller_list), ctrl_node) {
        if (ctrl->ctrl_ops->intr_pending(ctrl->priv_data)) {
            uint_t intr_num = ctrl->ctrl_ops->get_intr_number(ctrl->priv_data);
            
            //  PrintDebug("[get_intr_number] intr_number = %d\n", intr_num);
-           
-           return intr_num;
+           ret = intr_num;
+           break;
        }
     }
-    return 0;
+
+    v3_unlock_irqrestore(intr_state->irq_lock, irq_state);
+
+
+    return ret;
 }
 
 
 intr_type_t v3_get_intr_type(struct guest_info * info) {
     struct v3_intr_state * intr_state = &(info->intr_state);
     struct intr_controller * ctrl = NULL;
+    intr_type_t type = INVALID_INTR;
+
+    addr_t irq_state = v3_lock_irqsave(intr_state->irq_lock);  
 
     list_for_each_entry(ctrl, &(intr_state->controller_list), ctrl_node) {
        if (ctrl->ctrl_ops->intr_pending(ctrl->priv_data) == 1) {
            //PrintDebug("[get_intr_type] External_irq\n");
-           return EXTERNAL_IRQ;
+           type = EXTERNAL_IRQ;
+           break;
        }
     }
 
-    PrintError("[get_intr_type] Invalid_Intr\n");
-    return INVALID_INTR;
+#ifdef DEBUG_INTERRUPTS
+    if (type == INVALID_INTR) {
+       PrintError("[get_intr_type] Invalid_Intr\n");
+    }
+#endif
+
+    v3_unlock_irqrestore(intr_state->irq_lock, irq_state);
+
+    return type;
 }
 
 
@@ -238,10 +266,14 @@ int v3_injecting_intr(struct guest_info * info, uint_t intr_num, intr_type_t typ
     if (type == EXTERNAL_IRQ) {
        struct intr_controller * ctrl = NULL;
 
+       addr_t irq_state = v3_lock_irqsave(intr_state->irq_lock); 
+
        //      PrintDebug("[injecting_intr] External_Irq with intr_num = %x\n", intr_num);
        list_for_each_entry(ctrl, &(intr_state->controller_list), ctrl_node) {
            ctrl->ctrl_ops->begin_irq(ctrl->priv_data, intr_num);
        }
+
+       v3_unlock_irqrestore(intr_state->irq_lock, irq_state);
     }
 
     return 0;