This patch adds a trace event to the class 'xhci_log_msg', called
'xhci_dbg_missed_periodic_tx', that traces the debug statements which
signal that the xHC is unable to service an isochronous endpoint within
its service interval either because the endpoint's ring is full and can
not receive further data, for IN endpoints, or because the endpoint's ring
is empty, for OUT endpoints, or due to xHC internal buffers' overrun or
underrun caused by excessive latency on the transfer path.
Signed-off-by: Xenia Ragiadakou <burzalod...@gmail.com>
---
drivers/usb/host/xhci-ring.c | 19 ++++++++++++-------
drivers/usb/host/xhci-trace.h | 5 +++++
2 files changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index bc9ce03..06d3a8f 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2510,18 +2510,22 @@ static int handle_tx_event(struct xhci_hcd *xhci,
* a Ring Overrun Event for IN Isoch endpoint or Ring
* Underrun Event for OUT Isoch endpoint.
*/
- xhci_dbg(xhci, "underrun event on endpoint\n");
+ xhci_dbg_trace(xhci, trace_xhci_dbg_missed_periodic_tx,
+ "underrun event on endpoint");
if (!list_empty(&ep_ring->td_list))
- xhci_dbg(xhci, "Underrun Event for slot %d ep %d "
- "still with TDs queued?\n",
+ xhci_dbg_trace(xhci, trace_xhci_dbg_missed_periodic_tx,
+ "Underrun Event for slot %d ep %d "
+ "still with TDs queued?",
TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
ep_index);
goto cleanup;
case COMP_OVERRUN:
- xhci_dbg(xhci, "overrun event on endpoint\n");
+ xhci_dbg_trace(xhci, trace_xhci_dbg_missed_periodic_tx,
+ "overrun event on endpoint");
if (!list_empty(&ep_ring->td_list))
- xhci_dbg(xhci, "Overrun Event for slot %d ep %d "
- "still with TDs queued?\n",
+ xhci_dbg_trace(xhci, trace_xhci_dbg_missed_periodic_tx,
+ "Overrun Event for slot %d ep %d "
+ "still with TDs queued?",
TRB_TO_SLOT_ID(le32_to_cpu(event->flags)),
ep_index);
goto cleanup;
@@ -2537,7 +2541,8 @@ static int handle_tx_event(struct xhci_hcd *xhci,
* short transfer when process the ep_ring next time.
*/
ep->skip = true;
- xhci_dbg(xhci, "Miss service interval error, set skip flag\n");
+ xhci_dbg_trace(xhci, trace_xhci_dbg_missed_periodic_tx,
+ "Miss service interval error, set skip flag");
goto cleanup;
default:
if (xhci_is_vendor_info_code(xhci, trb_comp_code)) {
diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h
index 20364cc..c156685 100644
--- a/drivers/usb/host/xhci-trace.h
+++ b/drivers/usb/host/xhci-trace.h
@@ -67,6 +67,11 @@ DEFINE_EVENT(xhci_log_msg, xhci_dbg_ring_expansion,
TP_ARGS(vaf)
);
+DEFINE_EVENT(xhci_log_msg, xhci_dbg_missed_periodic_tx,
+ TP_PROTO(struct va_format *vaf),
+ TP_ARGS(vaf)
+);
+
DECLARE_EVENT_CLASS(xhci_log_ctx,
TP_PROTO(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx,
unsigned int ep_num),
--
1.8.3.4
--
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