Re: [PATCH][v3] blktrace: conversion to tracepoints

[Arnaldo Carvalho de Melo <acme@redhat.com>]

Em Thu, Oct 30, 2008 at 08:31:34AM +0100, Jens Axboe escreveu:
> On Wed, Oct 29 2008, Arnaldo Carvalho de Melo wrote:
> > Em Wed, Oct 29, 2008 at 02:18:55PM +0100, Jens Axboe escreveu:
> > > > 	Feel free to point any disgusting aspect, perhaps there is at
> > > > least one to warn me about fixing 8-)
> > > 
> > > You my as well pass the members separately now that it's a specific call
> > > anyway, to avoid doing the calculation when tracing is disabled.
> > > 
> > > Patch looks straight forward. Perhaps it would be cleaner to use an
> > > atomic type for the reference?
> > 
> > Done and made the old pdu_int + NULL bio (trace_block_unplug_{io,timer})
> > functions to receive just the request_queue.
> > 
> > Found and fixed a bug in the process:
> > 
> > In v2 we had:
> > 
> > +       unregister_trace_block_rq_insert(blk_add_trace_rq_insert);
> > +       unregister_trace_block_rq_insert(blk_add_trace_rq_abort);
> > 
> > Where it should have been:
> > 
> > +       unregister_trace_block_rq_insert(blk_add_trace_rq_insert);
> > +       unregister_trace_block_rq_abort(blk_add_trace_rq_abort);
> > 
> > c'n'p roblem!
> > 
> > Also removed the leftover tracepoint_synchronize_unregister macro, it
> > was already merged righfully as an inline function.
> > 
> > Everything should be rock solid now 8)
> 
> I'll apply this for 2.6.29. I'm assuming you have tested this as well?

Yes, I tested it, run 'btrace /dev/sda' several times, while doing a
45 GB backup using rsync over NFS, etc. So it should have exercised the
tracepoints use and repeated registrater/unregister cycles.

Thanks!

- Arnaldo