Re: [PATCH for-3.3/core] block: add missing block_bio_complete()tracepoint

From: Namhyung Kim
Date: Fri Feb 17 2012 - 22:32:36 EST


Hi,

2012-02-17, 13:19 -0800, Tejun Heo:
> bio completion didn't kick block_bio_complete TP. Only dm was
> explicitly triggering the TP on IO completion. This makes
> block_bio_complete TP useless for tracers which want to know about
> bios, and all other bio based drivers skip generating blktrace
> completion events.
>
> This patch makes all bio completions via bio_endio() generate
> block_bio_complete TP.
>
> * Explicit trace_block_bio_complete() invocation removed from dm and
> the trace point is unexported.
>
> * @rq dropped from trace_block_bio_complete(). bios may fly around
> w/o queue associated. Verifying and accessing the assocaited queue
> belongs to TP probes.
>
> * blktrace now gets both request and bio completions. Make it ignore
> bio completions if request completion path is happening.
>
> This makes all bio based drivers generate blktrace completion events
> properly and makes the block_bio_complete TP actually useful.
>
> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> Original-patch-by: Namhyung Kim <namhyung@xxxxxxxxx>
> Cc: Tejun Heo <tj@xxxxxxxxxx>
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
> Cc: dm-devel@xxxxxxxxxx

Looks better to me, thanks. :)


--
Regards,
Namhyung Kim


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