[PATCH 4.14 034/148] xhci: Do not open code __print_symbolic() in xhci trace events

[Greg Kroah-Hartman]

From: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

commit 045706bff837ee89c13f1ace173db71922c1c40b upstream.

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@xxxxxxxxxxxxxxx
Reported-by: Tzvetomir Stoyanov <tstoyanov@xxxxxxxxxx>
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@xxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20200306150858.21904-2-mathias.nyman@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/host/xhci-trace.h |   23 ++++++-----------------
 1 file changed, 6 insertions(+), 17 deletions(-)

--- a/drivers/usb/host/xhci-trace.h
+++ b/drivers/usb/host/xhci-trace.h
@@ -276,23 +276,12 @@ 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
 		)