Re: [PATCH 2/6] tracing: increase size of number of possibleevents

[Steven Rostedt]

On Fri, 24 Apr 2009, Ingo Molnar wrote:

> 
> * Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> 
> > From: Steven Rostedt <srostedt@xxxxxxxxxx>
> > 
> > With the new event tracing registration, we must increase the number
> > of events that can be registered. Currently the type field is only
> > one byte, which leaves us only 256 possible events.
> > 
> > Since we do not save the CPU number in the tracer anymore (it is determined
> > by the per cpu ring buffer that is used) we have an extra byte to use.
> > 
> > This patch increases the size of type from 1 byte (256 events) to
> > 2 bytes (65,536 events).
> > 
> > It also adds a WARN_ON_ONCE if we exceed that limit.
> > 
> > [ Impact: allow more than 255 events ]
> 
> > -	int			type;
> > +	unsigned short		type;
> 
> Hm, the changelog is not valid anymore - as here we really cut it 
> down from 4 billion to 64K, right?

[ Impact: wrong changelog due to forward port of patch ]

;-)

-- Steve

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