From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Moyer <jmoyer@redhat.com>
Subject: Re: [patch] nd_blk,nd_pmem,nd_btt: add endio blktrace events
Date: Wed, 16 Nov 2016 09:06:11 -0500
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In-Reply-To: <20161116045657.GA30049@linux.intel.com> (Ross Zwisler's message
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To: Ross Zwisler <ross.zwisler@linux.intel.com>
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Ross Zwisler <ross.zwisler@linux.intel.com> writes:

> FWIW I think BRD has this same issue where we get block_bio_queue tracepoint
> events but not block_bio_complete.  Solving this in bio_endio() would fix that
> driver as well.

Yeah, there are several other drivers that will benefit.

> Where does the Q (bio enqueue), I (req insert), etc. naming show up?  Looking
> at a tracepoint trace in perf I don't see that naming.  Is that just a short
> hand used between developers, or is it something else?

That shorthand appears in blkparse and btt output (tools that are part
of blktrace).

Cheers,
Jeff