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Message-ID: <bf3792800604180012s4c96fae2g3725f52690af9a0d@mail.gmail.com>
Date: Tue, 18 Apr 2006 15:12:35 +0800
From: "Liu haixiang" <liu.haixiang@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: Question on Schedule and Preemption
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Hi All,

Now I am developing drivers on Linux 2.6.

My problem is that from time to time, I will get log meesage from
kernel: "scheduling while atomic ..." and the stack will be dumped by
the kernel.

Then I investigate the code in sched.c but don't understand. Anybody
can clarify this piece of code for me?

if (likely(!current->exit_state)) {
	if (unlikely(in_atomic())) {
		printk(KERN_ERR "scheduling while atomic: "
			"%s/0x%08x/%d\n",
			current->comm, preempt_count(), current->pid);
		dump_stack();
	}
}

Thanks a lot

Haixiang