[PATCH 1/1] serial: 8250, disable "too much work" messages

From: Jiri Slaby
Date: Tue Apr 01 2014 - 07:37:19 EST


The 8250 driver now reports many of these:
serial8250: too much work for irq4
These messages turned out to be common these days with a use of
virtualization. I tried to increase the limit of processed characters
in commit e7328ae1848966181a7ac47e8ae6cddbd2cf55f3 (serial: 8250,
increase PASS_LIMIT) in 2011. It was raised from 256 to 512, but it is
still not enough, apparently.

So disable the warning unless somebody turns on DEBUG (or
DYNAMIC_DEBUG _and_ the message).

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Reported-by: Martin Pluskal <mpluskal@xxxxxxxx>
Reported-by: Takashi Iwai <tiwai@xxxxxxxx>
References: https://bugzilla.novell.com/show_bug.cgi?id=868394
---
drivers/tty/serial/8250/8250_core.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 81f909c2101f..139ab1997e06 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -1601,8 +1601,7 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id)
l = l->next;

if (l == i->head && pass_counter++ > PASS_LIMIT) {
- /* If we hit this, we're dead. */
- printk_ratelimited(KERN_ERR
+ pr_debug_ratelimited(
"serial8250: too much work for irq%d\n", irq);
break;
}
--
1.9.1

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