diff -urN c/xen/common/keyhandler.c d/xen/common/keyhandler.c
--- c/xen/common/keyhandler.c	2005-06-02 22:21:41.000000000 -0500
+++ d/xen/common/keyhandler.c	2005-06-03 09:48:15.075135457 -0500
@@ -12,6 +12,7 @@
 #include <xen/softirq.h>
 #include <xen/domain.h>
 #include <asm/debugger.h>
+#include <public/xen.h>
 
 #define KEY_MAX 256
 #define STR_MAX  64
@@ -139,6 +140,33 @@
     read_unlock(&domlist_lock);
 }
 
+static void do_dump_confer(unsigned char key)
+{
+    struct domain *d;
+    struct vcpu *v;
+    s_time_t       now = NOW();
+
+    printk("'%c' pressed -> dumping confer stats (now=0x%X:%08X)\n", key,
+           (u32)(now>>32), (u32)now);
+
+    read_lock(&domlist_lock);
+    for_each_domain ( d )
+    {
+        for_each_vcpu ( d, v )
+        {
+            printk("Xen: D%d, V%d, C%d,"
+                   " cnfs %d, c_out %d,"
+                   " c_in %d, ycnt %d\n",
+                   d->domain_id, v->vcpu_id, v->processor,
+                   v->confercnt, v->confer_out, 
+                   v->confer_in, v->vcpu_info->yield_count
+                  );
+        }
+
+    }
+    read_unlock(&domlist_lock);
+}
+
 extern void dump_runq(unsigned char key);
 extern void print_sched_histo(unsigned char key);
 extern void reset_sched_histo(unsigned char key);
@@ -184,6 +212,8 @@
     register_keyhandler(
         'q', do_task_queues, "dump task queues + guest state");
     register_keyhandler(
+        'c', do_dump_confer, "dump confer stats");
+    register_keyhandler(
         'r', dump_runq,      "dump run queues");
     register_irq_keyhandler(
         'R', halt_machine,   "reboot machine"); 
diff -urN c/xen/common/schedule.c d/xen/common/schedule.c
--- c/xen/common/schedule.c	2005-06-03 09:41:49.540601494 -0500
+++ d/xen/common/schedule.c	2005-06-03 09:46:01.768032249 -0500
@@ -223,6 +223,9 @@
         if ( test_bit(_VCPUF_conferring, &current->vcpu_flags) ) {
             clear_bit(_VCPUF_conferring, &current->vcpu_flags);
             set_bit(_VCPUF_conferred, &current->vcpu_flags);
+            /* increment confer counters */
+            current->confer_out++;
+            v->confer_in++;
         }
         SCHED_OP(wake, v);
 #ifdef WAKE_HISTO
@@ -270,6 +273,9 @@
 {
     struct domain *d = current->domain;
    
+    /* count hcalls */
+    current->confercnt++;
+
     /* Validate CONFER prereqs:
     * - vcpu is within bounds
     * - vcpu is a valid in this domain
@@ -286,16 +292,22 @@
     if (unlikely(d->vcpu[vcpu] == NULL))
         return 0;
 
-    if (unlikely(!test_bit(_VCPUF_canconfer, &current->vcpu_flags)))
+    if (unlikely(!test_bit(_VCPUF_canconfer, &current->vcpu_flags))) {
+         printk("confer: canconfer not set, %d->vcpu-flags = 0x%08lx\n", current->vcpu_id, current->vcpu_flags);
         return 0;
+    }
 
     /* even counts indicate a running vcpu, odd is preempted/conferred */
     /* don't confer if holder is currently running */
-    if (unlikely((d->vcpu[vcpu]->vcpu_info->yield_count & 1) == 0))
+    if (unlikely((d->vcpu[vcpu]->vcpu_info->yield_count & 1) == 0)) {
+        printk("confer: vcpu %d already running\n", vcpu);
         return 0;
+    }
 
-    if (unlikely(d->vcpu[vcpu]->vcpu_info->yield_count != yield_count))
+    if (unlikely(d->vcpu[vcpu]->vcpu_info->yield_count != yield_count)) {
+        printk("confer: yield_count mismatch\n");
         return 0;
+    }
 
     /*
      * set current's state to conferring, wake target
diff -urN c/xen/include/xen/sched.h d/xen/include/xen/sched.h
--- c/xen/include/xen/sched.h	2005-06-03 09:41:11.042994158 -0500
+++ d/xen/include/xen/sched.h	2005-06-03 09:43:52.881249246 -0500
@@ -76,6 +76,9 @@
     atomic_t         pausecnt;
 
     cpumap_t         cpumap;        /* which cpus this domain can run on */
+    u32              confer_out;    /* inc when conferring to another vcpu */
+    u32              confer_in;     /* inc when conferred from another vcpu */
+    u32              confercnt;     /* # of do_confer hcalls */
 
     struct arch_vcpu arch;
 };