lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Sat, 20 Jan 2007 15:54:00 +0530
From:	"kalash nainwal" <nirvana.code@...il.com>
To:	netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: wake_up() takes long time to return

Hi there,

We've a kernel (n/w) module, which sits over ethernet. Whenever a pkt
is received (in softirq), after doing some minimal processing,
wake_up() is called to wake up another kernel thread which does rest
(bulk) of the processing.

We notice that this wake_up() call is sometimes taking as long as 48
milli-seconds to return. This happens around 10 times out of 10M. We
earlier thought its possibly because of the contention on rq->lock,
but we see the same phenomenon even on a uniprocessor box. So obviosly
thats not the case.

We can't figure out any other reason for wake_up() to take this much
time? As this call comes directly in our (receive) hotpath, we're very
concerned. Any help would be greatly appreciated.

Thanks and regards,
-Kalash
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists