# HG changeset patch
# User rob.gardner@hp.com
# Node ID 81e7d6e0f9109bf493b7c8281ffc79d10f4dd2ab
# Parent  67f658b84025efeb2a570d2937ebc8f5e35056f7

New trace event is introduced to track lost trace records.

diff -r 67f658b84025 -r 81e7d6e0f910 xen/common/trace.c
--- a/xen/common/trace.c	Thu Jul  6 18:08:37 2006
+++ b/xen/common/trace.c	Thu Jul  6 23:29:26 2006
@@ -234,7 +234,8 @@
     struct t_buf *buf;
     struct t_rec *rec;
     unsigned long flags;
-
+    static long lost_records = 0;
+    
     BUG_ON(!tb_init_done);
 
     if ( (tb_event_mask & event) == 0 )
@@ -261,8 +262,24 @@
 
     if ( (buf->prod - buf->cons) >= nr_recs )
     {
+        lost_records++;
         local_irq_restore(flags);
         return;
+    }
+
+    if (lost_records) {
+        rec = &t_recs[smp_processor_id()][buf->prod % nr_recs];
+        rec->cycles  = (u64)get_cycles();
+        rec->event   = TRC_LOST_RECORDS;
+        rec->data[0] = lost_records;
+        rec->data[1] = 0;
+        rec->data[2] = 0;
+        rec->data[3] = 0;
+        rec->data[4] = 0;
+        
+        wmb();
+        buf->prod++;
+        lost_records = 0;
     }
 
     rec = &t_recs[smp_processor_id()][buf->prod % nr_recs];
diff -r 67f658b84025 -r 81e7d6e0f910 xen/include/public/trace.h
--- a/xen/include/public/trace.h	Thu Jul  6 18:08:37 2006
+++ b/xen/include/public/trace.h	Thu Jul  6 23:29:26 2006
@@ -26,6 +26,7 @@
 #define TRC_VMXIO    0x00088000   /* VMX io emulation trace  */
 
 /* Trace events per class */
+#define TRC_LOST_RECORDS        (TRC_GEN + 1)
 
 #define TRC_SCHED_DOM_ADD       (TRC_SCHED +  1)
 #define TRC_SCHED_DOM_REM       (TRC_SCHED +  2)