serial_core: Update buffer overrun statistics.

Currently, serial drivers don't report buffer overruns. When a buffer overrun
occurs, tty_insert_flip_char returns 0, and no attempt is made to insert that
same character again (i.e. it is lost). This patch reports buffer overruns via
the buf_overrun field in the port's icount structure.

Signed-off-by: Corbin Atkinson <corbin.atkinson@xxxxxx>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Corbin 2012-05-23 09:37:31 -05:00 committed by Greg Kroah-Hartman
parent 10e7d0980f
commit 24a7d449b0

View File

@ -2527,14 +2527,16 @@ void uart_insert_char(struct uart_port *port, unsigned int status,
struct tty_struct *tty = port->state->port.tty;
if ((status & port->ignore_status_mask & ~overrun) == 0)
tty_insert_flip_char(tty, ch, flag);
if (tty_insert_flip_char(tty, ch, flag) == 0)
++port->icount.buf_overrun;
/*
* Overrun is special. Since it's reported immediately,
* it doesn't affect the current character.
*/
if (status & ~port->ignore_status_mask & overrun)
tty_insert_flip_char(tty, 0, TTY_OVERRUN);
if (tty_insert_flip_char(tty, 0, TTY_OVERRUN) == 0)
++port->icount.buf_overrun;
}
EXPORT_SYMBOL_GPL(uart_insert_char);