RE: 2.6.9: serial_core: uart_open

From: karl malbrain
Date: Tue Jul 12 2005 - 16:21:57 EST




-----Original Message-----
From: Russell King
Sent: Tuesday, July 12, 2005 2:04 PM
To: karl malbrain
Cc: linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: 2.6.9: serial_core: uart_open


On Tue, Jul 12, 2005 at 11:36:51AM -0700, karl malbrain wrote:
> The uart_open code loops waiting for CD to be asserted (whenever CLOCAL
> is not set). The bottom of the loop contains the following code:
>
> up(&state->sem);
> schedule();
> down(&state->sem);
>
> if( signal_pending(current) )
> break;

This does cause the process to sleep - in an interruptible wait.

Please give more details about the problem you're seeing. Have you
tried getting a process listing from a different virtual console,
xterm or whatever you normally use? What does that say?

--
Russell King
Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/
maintainer of: 2.6 Serial core

Sorry, but I cannot get anything else to run. I can barely get XWindows to
kill the process.

What prevents schedule() from returning to the current process w/o any
delay?

Thanks, karl m




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