From: "Steve Wise" <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
To: "'Hefty,
Sean'" <sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
'Hal Rosenstock'
<hal-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org>,
'Leon Romanovsky' <leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
'Sagi Grimberg' <sagi-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org>,
'Hal Rosenstock' <hal-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Cc: 'Jason Gunthorpe'
<jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>,
linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-nvme-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
'Christoph Hellwig' <hch-jcswGhMUV9g@public.gmane.org>
Subject: RE: Flush warning
Date: Mon, 14 Aug 2017 12:21:40 -0500 [thread overview]
Message-ID: <00be01d31521$cb237900$616a6b00$@opengridcomputing.com> (raw)
In-Reply-To: <1828884A29C6694DAF28B7E6B8A82373AB17595A-P5GAC/sN6hkd3b2yrw5b5LfspsVTdybXVpNB7YpNyf8@public.gmane.org>
> > >>> The workqueue which frees the memory and doesn't allocate memory
> > >>> during execution is supposed to be marked as WQ_MEM_RECLAIM. This
> > >>> flag will cause to priority increase for such workqueue during low
> > memory conditions.
> > >>
> > >> Which to my understanding means that CM workqueue should not use it
> > >> as on each CM connect, by definition the ULP allocates memory (qp,
> > cq etc).
> > >
> > > From my understanding too.
> > > That workqueue was introduced in 2005, in a977049dacde ("[PATCH] IB:
> > > Add the kernel CM implementation"), it is not clear if it was
> > > intentionally.
> > >
> > > Hal,
> > > do you remember the rationale there?
> >
> > Sean is best to respond to this.
>
> I believe the work queue was to avoid potential deadlocks that could arise
from
> using the MAD work queue. The original submission did not mark the work queue
> with WQ_MEM_RECLAIM. I do not know when that change was added.
By the way, the queue I'm actually having the problem with is in the iwcm, not
the ibcm. I think we should remove WQ_MEM_RECLAIM from all the CM queues
because I agree now that ulps potentially can/will allocate memory in the
contect of these workqueues...
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2017-08-14 17:21 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-03 18:32 Flush warning Steve Wise
2017-08-07 1:06 ` Sagi Grimberg
[not found] ` <9bc142de-b8ba-acb6-5ea1-2ccdbb578655-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org>
2017-08-07 15:28 ` Steve Wise
2017-08-09 16:21 ` Steve Wise
2017-08-09 16:27 ` Jason Gunthorpe
[not found] ` <20170809162749.GA4069-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2017-08-09 16:38 ` Steve Wise
2017-08-13 6:46 ` Leon Romanovsky
[not found] ` <20170813064651.GR24282-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
2017-08-13 9:14 ` Sagi Grimberg
[not found] ` <90ada4f5-d6a1-2b93-5164-c593955c20cf-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org>
2017-08-13 10:33 ` Leon Romanovsky
[not found] ` <20170813103359.GW24282-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
2017-08-14 12:13 ` Hal Rosenstock
[not found] ` <3d9cca62-4612-53dc-776c-3aeb2df58365-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org>
2017-08-14 17:01 ` Hefty, Sean
[not found] ` <1828884A29C6694DAF28B7E6B8A82373AB17595A-P5GAC/sN6hkd3b2yrw5b5LfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2017-08-14 17:21 ` Steve Wise [this message]
2017-08-15 9:09 ` Sagi Grimberg
[not found] ` <64134765-9a10-d014-3ac4-b0f747d6c670-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org>
2017-08-15 13:42 ` Steve Wise
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='00be01d31521$cb237900$616a6b00$@opengridcomputing.com' \
--to=swise-7bpotxp6k4+p2yhjcf5u+vpxobypeauw@public.gmane.org \
--cc=hal-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org \
--cc=hal-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org \
--cc=hch-jcswGhMUV9g@public.gmane.org \
--cc=jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org \
--cc=leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
--cc=linux-nvme-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
--cc=linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=sagi-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org \
--cc=sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org \
/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