Insert markers in console stream instead of making console output
glued together when drops happen.
Signed-off-by: Michał Mirosław <mirq-linux@xxxxxxxxxxxx>
---
drivers/usb/gadget/function/u_serial.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
index 7b719c166517..f025cb958362 100644
--- a/drivers/usb/gadget/function/u_serial.c
+++ b/drivers/usb/gadget/function/u_serial.c
@@ -88,6 +88,7 @@ struct gs_console {
spinlock_t lock;
struct usb_request *req;
struct kfifo buf;
+ size_t missed;
};
/*
@@ -930,6 +931,15 @@ static void __gs_console_push(struct gs_console *cons)
if (!size)
return;
+ if (cons->missed && ep->maxpacket >= 64) {
+ char buf[64];
+ size_t len;
+
+ len = sprintf(buf, "\n[MISSED %zu bytes]\n", cons->missed);
+ kfifo_in(&cons->buf, buf, len);
+ cons->missed = 0;
+ }
+
req->length = size;
if (usb_ep_queue(ep, req, GFP_ATOMIC))
req->length = 0;
@@ -951,10 +961,13 @@ static void gs_console_write(struct console *co,
{
struct gs_console *cons = container_of(co, struct gs_console, console);
unsigned long flags;
+ size_t n;
spin_lock_irqsave(&cons->lock, flags);
- kfifo_in(&cons->buf, buf, count);
+ n = kfifo_in(&cons->buf, buf, count);
+ if (n < count)
+ cons->missed += count - n;
if (cons->req && !cons->req->length)
schedule_work(&cons->work);
--
2.20.1
