Re: changing format/size of data in TRACE_EVENT(extlog_mem_event)

[Steven Rostedt]

On Wed, 24 Jun 2015 14:56:49 -0700
"Luck, Tony" <tony.luck@xxxxxxxxx> wrote:


> So the question is - how can we update the trace event to include these
> new wider fields with the minimum pain to applications that look at it?
> I don't know if there are any other consumers besides rasdaemon at the
> moment ... but we don't want ugly transitions where you have to guess
> which version of the application you need to run to work with a given
> kernel version.

It comes down to if the rasdaemon (and any other user) included the
event_parse.c "library" (it's not a public library yet, and we really
should make it one). Because if it did, it doesn't matter what the
field is, the event descriptions will give the size, and as long as the
name of a field exists, and it doesn't change type (that is, from
integer to string), it should be fine.

-- Steve
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