X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?p=pintos-anon;a=blobdiff_plain;f=src%2Fthreads%2Finterrupt.c;h=e3b90dcb566e3512b8ea1b9e69d2544d64e5933b;hp=9ffd873540b803ca3414b83f10c6da4e8c4b2f54;hb=ffdf5a5f292d3ae73f62422ad66297eb84da26c4;hpb=6ffbc2b68c34c2d1e42d5f6bcd8f2b94b82d05d7

diff --git a/src/threads/interrupt.c b/src/threads/interrupt.c
index 9ffd873..e3b90dc 100644
--- a/src/threads/interrupt.c
+++ b/src/threads/interrupt.c
@@ -33,6 +33,10 @@ static intr_handler_func *intr_handlers[INTR_CNT];
 /* Names for each interrupt, for debugging purposes. */
 static const char *intr_names[INTR_CNT];
 
+/* Number of unexpected interrupts for each vector.  An
+   unexpected interrupt is one that has no registered handler. */
+static unsigned int unexpected_cnt[INTR_CNT];
+
 /* External interrupts are those generated by devices outside the
    CPU, such as the timer.  External interrupts run with
    interrupts turned off, so they never nest, nor are they ever
@@ -54,6 +58,7 @@ static inline uint64_t make_idtr_operand (uint16_t limit, void *base);
 
 /* Interrupt handlers. */
 void intr_handler (struct intr_frame *args);
+static void unexpected_interrupt (const struct intr_frame *);
 
 /* Returns the current interrupt status. */
 enum intr_level
@@ -366,13 +371,8 @@ intr_handler (struct intr_frame *frame)
          spuriously due to a hardware fault or hardware race
          condition.  Ignore it. */
     }
-  else 
-    {
-      /* No handler and not spurious.  Invoke the unexpected
-         interrupt handler. */
-      intr_dump_frame (frame);
-      PANIC ("Unexpected interrupt"); 
-    }
+  else
+    unexpected_interrupt (frame);
 
   /* Complete the processing of an external interrupt. */
   if (external) 
@@ -388,6 +388,24 @@ intr_handler (struct intr_frame *frame)
     }
 }
 
+/* Handles an unexpected interrupt with interrupt frame F.  An
+   unexpected interrupt is one that has no registered handler. */
+static void
+unexpected_interrupt (const struct intr_frame *f)
+{
+  /* Count the number so far. */
+  unsigned int n = ++unexpected_cnt[f->vec_no];
+
+  /* If the number is a power of 2, print a message.  This rate
+     limiting means that we get information about an uncommon
+     unexpected interrupt the first time and fairly often after
+     that, but one that occurs many times will not overwhelm the
+     console. */
+  if ((n & (n - 1)) == 0)
+    printf ("Unexpected interrupt %#04x (%s)\n",
+    f->vec_no, intr_names[f->vec_no]);
+}
+
 /* Dumps interrupt frame F to the console, for debugging. */
 void
 intr_dump_frame (const struct intr_frame *f)