Add trace support for echo output but leave it separately selectable/ buildable from the base trace support.
Signed-off-by: Peter Hurley <[email protected]> --- drivers/tty/n_tty.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 26ae9d7..bd01d97 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -94,6 +94,13 @@ # define n_tty_trace(tty, f, args...) do { } while (0) #endif +#undef N_TTY_TRACE_ECHOES +#ifdef N_TTY_TRACE_ECHOES +# define n_tty_trace_echoes(tty, f, args...) _n_tty_trace(tty, f, args) +#else +# define n_tty_trace_echoes(tty, f, args...) do { } while (0) +#endif + struct n_tty_data { /* producer-published */ size_t read_head; @@ -791,13 +798,18 @@ static size_t __process_echoes(struct tty_struct *tty) } } + n_tty_trace_echoes(tty, "echoes:%zu,%zu commit:%zu head:%zu\n", + ldata->echo_tail, tail, ldata->echo_commit, + ldata->echo_head); + /* If the echo buffer is nearly full (so that the possibility exists * of echo overrun before the next commit), then discard enough * data at the tail to prevent a subsequent overrun */ while (ldata->echo_commit - tail >= ECHO_DISCARD_WATERMARK) { - n_tty_trace(tty, "discard echoes (%zu - %zu > %d)\n", - ldata->echo_commit, tail, ECHO_DISCARD_WATERMARK); + n_tty_trace_echoes(tty, "discard echoes (%zu - %zu > %d)\n", + ldata->echo_commit, tail, + ECHO_DISCARD_WATERMARK); if (echo_buf(ldata, tail) == ECHO_OP_START) { if (echo_buf(ldata, tail + 1) == ECHO_OP_ERASE_TAB) -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
