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Date: Tue, 25 Nov 2008 12:59:22 +0100
From: "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" <fweisbec@gmail.com>
To: "Pekka Paalanen" <pq@iki.fi>
Subject: Re: [PATCH 1/2] mmiotrace: fix buffer overrun detection
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2008/11/25 Frédéric Weisbecker <fweisbec@gmail.com>:
> Perhaps that:
>
> int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
> {
>     ......
>     if (tracing_disabled)
>                return 0;

Since this is the return value for tracing_mark_write(), it may better
return an error to avoid a spin when tracing
is disabled. -ENODEV I guess, or -EBUSY

The strange thing is that tracing_open_generic() shoud have return
-ENODEV in this case during the opening of trace_mark.