Messages in this thread | | | Date | Sat, 23 Nov 2013 21:38:56 -0500 | From | Peter Hurley <> | Subject | Re: [PATCH tty-next 7/7] n_tty: trace input/read flow control |
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On 11/23/2013 07:25 PM, One Thousand Gnomes wrote: > On Fri, 22 Nov 2013 10:59:25 -0500 > Peter Hurley <peter@hurleysoftware.com> wrote: > >> Instrument .receive_buf() and read() paths with trace_printk's >> to aid in debugging flow control changes. > > tty devices have a device, we have a dev_dbg() layer. The old tty trace > predates this but there isn't really any excuse for not using it now that > I can see ?
I was using the ftrace facility because it has significantly less performance impact than printk (which was an important factor while debugging flow control problems).
That said, I could further macro-ize n_tty_trace() with selectable facility (which would be useful when debugging problems that end in cpu death).
Regards, Peter Hurley
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