Re: [PATCH 0/9] jump label v6

[Jason Baron <jbaron@redhat.com>]

On Tue, Apr 13, 2010 at 12:56:59PM -0400, Mathieu Desnoyers wrote:
> * Jason Baron (jbaron@redhat.com) wrote:
> > Hi,
> > 
> > Refresh of jump labeling patches aginst -tip tree. For bacground see: 
> > http://marc.info/?l=linux-kernel&m=125858436505941&w=2
> > 
> > I believe I've addressed all the reviews from v5.
> 
> Hi Jason,
> 
> I would appreciate if you could add pointers to the Immediate Values
> benchmarks (or possibly some benchmark information altogether) and a
> notice that some parts of the design are inspired from Immediate Values
> in the jump label code.
> 
> I recognise that you did great work on getting jump label in shape both
> at the Linux kernel and gcc level, but it's usually appropriate to
> acknowledge prior work it is based on. Only then can I justify that
> Immediate Values have been useful in the whole process.
> 

So I've been doing micro-benchmarks measuring the cycles involved when
the tracepoints are disabled. As quoted from the above pointer:

"As discussed in pervious mails I've seen an average improvement of 30
cycles per-tracepoint on x86_64 systems that I've tested."

I can post my test harness if you are interested.

If there are any other benchmarks of interest please let me know.

I am planning to add a Docmentation/ file for jump labels, so I can add
about the previous Immediate value work, which certainly has been
useful.

thanks,

-Jason