[PATCH v2 08/11] gpiolib: emit a debug message when adding events to a full kfifo

From: Bartosz Golaszewski
Date: Wed Dec 04 2019 - 11:02:01 EST


From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>

Currently if the line-event kfifo is full, we just silently drop any new
events. Add a ratelimited debug message so that we at least have some
trace in the kernel log of event overflow.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
---
drivers/gpio/gpiolib.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 43f90eca6d45..c89d297da270 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -975,6 +975,9 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p)
ret = kfifo_in_spinlocked(&le->events, &ge, 1, &le->wait.lock);
if (ret)
wake_up_poll(&le->wait, EPOLLIN);
+ else
+ pr_debug_ratelimited(
+ "%s: event FIFO is full - event dropped\n", __func__);

return IRQ_HANDLED;
}
--
2.23.0