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Date: Wed, 9 Nov 2016 11:34:41 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Jeff Moyer <jmoyer@redhat.com>
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        "Dan J. Williams" <dan.j.williams@intel.com>,
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Subject: Re: [patch] nd_blk,nd_pmem,nd_btt: add endio blktrace events
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On Wed, Nov 09, 2016 at 02:31:30PM -0500, Jeff Moyer wrote:
> bio_endio is still called for request_fn drivers, so you'd see two
> completion events for those drivers if we did that, no?

We'd see the bio_endio trace in addition to the request one, but
they are at different granularities.  Similar to how on the issue side
we have trace_block_bio_queue for each bio, and trace_block_rq_issue
for each request.

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: Re: [patch] nd_blk,nd_pmem,nd_btt: add endio blktrace events
Date: Wed, 9 Nov 2016 11:34:41 -0800
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On Wed, Nov 09, 2016 at 02:31:30PM -0500, Jeff Moyer wrote:
> bio_endio is still called for request_fn drivers, so you'd see two
> completion events for those drivers if we did that, no?

We'd see the bio_endio trace in addition to the request one, but
they are at different granularities.  Similar to how on the issue side
we have trace_block_bio_queue for each bio, and trace_block_rq_issue
for each request.