Tracing block devices (was: Re: [Qemu-devel] Static tracepoint control via trace-event)

[Richard W.M. Jones]

On Tue, Oct 19, 2010 at 03:59:36PM +0200, Jan Kiszka wrote:
> Once we have "-trace events=...", defining the list of active
> tracepoints before starting qemu will be trivial (e.g. via a config
> file). Of course, this requires that all tracepoints are built-in...

Sorry that I've not been following this very closely, but does this
sort of thing allow tracing reads and writes to block devices?  Am I
right in thinking that if a tracepoint existed in the right place, one
could get a log file from that which could be post-processed in
another tool?

cf:
http://rwmj.wordpress.com/2010/10/05/visualizing-reads-writes-and-alignment/#content

Rich.

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