lkml.org 
[lkml]   [2006]   [Dec]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH] hpet: Avoid warning message livelock
From
Date
I've seen my box paralyzed by an endless spew of

rtc: lost some interrupts at 1024Hz.

messages on the serial console. What seems to be happening is that
something real causes an interrupt to be lost and triggers the
message. But then printing the message to the serial console (from
the hpet interrupt handler) takes more than 1/1024th of a second, and
then some more interrupts are lost, so the message triggers again....

Fix this by adding a printk_ratelimit() before printing the warning.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

---

diff --git a/arch/i386/kernel/time_hpet.c b/arch/i386/kernel/time_hpet.c
index 1e4702d..050c6af 100644
--- a/arch/i386/kernel/time_hpet.c
+++ b/arch/i386/kernel/time_hpet.c
@@ -367,8 +367,9 @@ static void hpet_rtc_timer_reinit(void)
if (PIE_on)
PIE_count += lost_ints;

- printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
- hpet_rtc_int_freq);
+ if (printk_ratelimit())
+ printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
+ hpet_rtc_int_freq);
}
}

diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 9f05bc9..fe13bb5 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -1204,8 +1204,9 @@ static void hpet_rtc_timer_reinit(void)
if (PIE_on)
PIE_count += lost_ints;

- printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
- hpet_rtc_int_freq);
+ if (printk_ratelimit())
+ printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
+ hpet_rtc_int_freq);
}
}

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2006-12-11 00:27    [W:0.027 / U:4.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site