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Date: Mon, 05 Sep 2011 10:38:41 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] ehci: avoid string arguments in trace
	events
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To: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: qemu-devel@nongnu.org

On 09/03/11 17:22, Stefan Hajnoczi wrote:
> String arguments are not supported by all trace backends.  This patch
> replaces existing string arguments in hw/usb-ehci.c either with
> individual trace events that remain human-friendly or by printing raw
> addresses when there is no alternative or downside to that.

Printing raw addresses *is* a downside.

> States and usbsts bits remain human-friendly since it is hard to
> remember all of them.  MMIO addresses are printed raw because they would
> create many individual trace events and the addresses are usually easy
> to remember when debugging.

I find it hard to rememeber them.  There is a reason why the code to 
print the names for the mmio addresses is there in the first place. I 
don't want to loose that.

Can't we just fix the backends instead?  Replacing debug fprintf with 
trace points isn't going to work if tracing can't handle strings.

cheers,
   Gerd