xhci: Do not open code __print_symbolic() in xhci trace events

libtraceevent (used by perf and trace-cmd) failed to parse the
xhci_urb_dequeue trace event. This is because the user space trace
event format parsing is not a full C compiler. It can handle some basic
logic, but is not meant to be able to handle everything C can do.

In cases where a trace event field needs to be converted from a number
to a string, there's the __print_symbolic() macro that should be used:

 See samples/trace_events/trace-events-sample.h

Some xhci trace events open coded the __print_symbolic() causing the
user spaces tools to fail to parse it. This has to be replaced with
__print_symbolic() instead.

CC: stable@vger.kernel.org
Reported-by: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206531
Fixes: 5abdc2e6e12ff ("usb: host: xhci: add urb_enqueue/dequeue/giveback tracers")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20200214115634.30e8ebf2@gandalf.local.home
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h
index 56eb867..b19582b 100644 (file)
--- a/drivers/usb/host/xhci-trace.h
+++ b/drivers/usb/host/xhci-trace.h
@@ -289,23 +289,12 @@ DECLARE_EVENT_CLASS(xhci_log_urb,
        ),
        TP_printk("ep%d%s-%s: urb %p pipe %u slot %d length %d/%d sgs %d/%d stream %d flags %08x",
                        __entry->epnum, __entry->dir_in ? "in" : "out",
-                       ({ char *s;
-                       switch (__entry->type) {
-                       case USB_ENDPOINT_XFER_INT:
-                               s = "intr";
-                               break;
-                       case USB_ENDPOINT_XFER_CONTROL:
-                               s = "control";
-                               break;
-                       case USB_ENDPOINT_XFER_BULK:
-                               s = "bulk";
-                               break;
-                       case USB_ENDPOINT_XFER_ISOC:
-                               s = "isoc";
-                               break;
-                       default:
-                               s = "UNKNOWN";
-                       } s; }), __entry->urb, __entry->pipe, __entry->slot_id,
+                       __print_symbolic(__entry->type,
+                                  { USB_ENDPOINT_XFER_INT,     "intr" },
+                                  { USB_ENDPOINT_XFER_CONTROL, "control" },
+                                  { USB_ENDPOINT_XFER_BULK,    "bulk" },
+                                  { USB_ENDPOINT_XFER_ISOC,    "isoc" }),
+                       __entry->urb, __entry->pipe, __entry->slot_id,
                        __entry->actual, __entry->length, __entry->num_mapped_sgs,
                        __entry->num_sgs, __entry->stream, __entry->flags
                )