linux-raid.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: NeilBrown <neilb@suse.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>,
	linux-raid@vger.kernel.org, Mike Snitzer <snitzer@redhat.com>,
	linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
	dm-devel@redhat.com, Shaohua Li <shli@kernel.org>,
	Alasdair Kergon <agk@redhat.com>
Subject: Re: [PATCH] block: trace completion of all bios.
Date: Thu, 23 Mar 2017 17:26:11 +1100	[thread overview]
Message-ID: <87var0a4qk.fsf@notabene.neil.brown.name> (raw)
In-Reply-To: <20170322125149.GA29606@infradead.org>


[-- Attachment #1.1: Type: text/plain, Size: 901 bytes --]

On Wed, Mar 22 2017, Christoph Hellwig wrote:

> On Wed, Mar 22, 2017 at 01:38:09PM +1100, NeilBrown wrote:
>> 
>> Currently only dm and md/raid5 bios trigger trace_block_bio_complete().
>> Now that we have bio_chain(), it is not possible, in general, for a
>> driver to know when the bio is really complete.  Only bio_endio()
>> knows that.
>> 
>> So move the trace_block_bio_complete() call to bio_endio().
>
> This will cause duplicate events for request based drivers.  You'll
> need to have a bio_endio_notrace or similar without that the request
> completion path can call.

Ah... I hadn't noticed that the request completion was the same event
type as the bio completion...  Thanks.  Also after being processed by the
request handler, bi_sector and bi_size have changed so the trace
messsage would be wrong.

I've sorted that out and will repost.

Thanks,
NeilBrown



[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]

[-- Attachment #2: Type: text/plain, Size: 0 bytes --]



  reply	other threads:[~2017-03-23  6:26 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-22  2:38 [PATCH] block: trace completion of all bios NeilBrown
2017-03-22 12:51 ` Christoph Hellwig
2017-03-23  6:26   ` NeilBrown [this message]
2017-03-23  6:29   ` [PATCH v2] " NeilBrown
2017-03-23 10:43     ` Ming Lei
2017-03-24  0:06       ` NeilBrown
2017-03-24  0:07       ` [PATCH v3] " NeilBrown
2017-03-24  6:47         ` Ming Lei
2017-03-26 23:17           ` NeilBrown
2017-03-27  9:03         ` Christoph Hellwig
2017-03-27  9:49           ` NeilBrown
2017-03-27 17:14             ` Christoph Hellwig
2017-03-27 23:42               ` [dm-devel] " NeilBrown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87var0a4qk.fsf@notabene.neil.brown.name \
    --to=neilb@suse.com \
    --cc=agk@redhat.com \
    --cc=axboe@kernel.dk \
    --cc=dm-devel@redhat.com \
    --cc=hch@infradead.org \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-raid@vger.kernel.org \
    --cc=shli@kernel.org \
    --cc=snitzer@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).