Index: sys/dev/acpica/acpi_cpu.c
===================================================================
--- sys/dev/acpica/acpi_cpu.c	(revision 264205)
+++ sys/dev/acpica/acpi_cpu.c	(working copy)
@@ -172,6 +172,7 @@
 static void	acpi_cpu_notify(ACPI_HANDLE h, UINT32 notify, void *context);
 static int	acpi_cpu_quirks(void);
 static int	acpi_cpu_usage_sysctl(SYSCTL_HANDLER_ARGS);
+static int	acpi_cpu_usage_counters_sysctl(SYSCTL_HANDLER_ARGS);
 static int	acpi_cpu_set_cx_lowest(struct acpi_cpu_softc *sc);
 static int	acpi_cpu_cx_lowest_sysctl(SYSCTL_HANDLER_ARGS);
 static int	acpi_cpu_global_cx_lowest_sysctl(SYSCTL_HANDLER_ARGS);
@@ -938,6 +939,11 @@
 		    OID_AUTO, "cx_usage", CTLTYPE_STRING | CTLFLAG_RD,
 		    (void *)sc, 0, acpi_cpu_usage_sysctl, "A",
 		    "percent usage for each Cx state");
+    SYSCTL_ADD_PROC(&sc->cpu_sysctl_ctx,
+		    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->cpu_dev)),
+		    OID_AUTO, "cx_usage_counters", CTLTYPE_STRING | CTLFLAG_RD,
+		    (void *)sc, 0, acpi_cpu_usage_counters_sysctl, "A",
+		    "Cx sleep state counters");
 
     /* Signal platform that we can handle _CST notification. */
     if (!cpu_cx_generic && cpu_cst_cnt != 0) {
@@ -1237,7 +1243,36 @@
     return (0);
 }
 
+/*
+ * XXX TODO: actually add support to count each entry/exit
+ * from the Cx states.
+ */
 static int
+acpi_cpu_usage_counters_sysctl(SYSCTL_HANDLER_ARGS)
+{
+    struct acpi_cpu_softc *sc;
+    struct sbuf	 sb;
+    char	 buf[128];
+    int		 i;
+
+    sc = (struct acpi_cpu_softc *) arg1;
+
+    /* Print out the raw counters */
+    sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN);
+
+    for (i = 0; i < sc->cpu_cx_count; i++) {
+        sbuf_printf(&sb, "%u ", sc->cpu_cx_stats[i]);
+    }
+
+    sbuf_trim(&sb);
+    sbuf_finish(&sb);
+    sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
+    sbuf_delete(&sb);
+
+    return (0);
+}
+
+static int
 acpi_cpu_set_cx_lowest(struct acpi_cpu_softc *sc)
 {
     int i;