public inbox for linux-rdma@vger.kernel.org
 help / color / mirror / Atom feed
From: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
To: Shlomo Pongratz <shlomop-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Cc: Or Gerlitz <or.gerlitz-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	"Hefty,
	Sean" <sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
	Tzahi Oved <tzahio-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>,
	Roland Dreier <roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	"linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
	Christoph Lameter <cl-vYTEC60ixJUAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH V4 for-next 1/5] IB/core: Add RSS and TSS QP groups - suggesting BOF during OFA conf to further discuss that
Date: Tue, 30 Apr 2013 10:28:41 -0600	[thread overview]
Message-ID: <20130430162841.GA29903@obsidianresearch.com> (raw)
In-Reply-To: <517F8919.8060108-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>

On Tue, Apr 30, 2013 at 12:04:25PM +0300, Shlomo Pongratz wrote:

> >And.. 'tss_qpn_mask_sz' seems unnecessarily limiting, using
> >  WC.srcQPN + ipoib_header.tss_qpn_offset == real QPN
> >  (ie use a signed offset, not a mask)
> >Seems much better than
> >  Wc.srcQPN & ~((1<<(ipoib_header.tss_qpn_mask_sz >> 12))-1) == real QPN
> >  (Did I even get that right?)

> Your suggestion could have been valid if the the IPoIB header was larger.
> Please note that the a QPN occupies 3 octets and thus its value lies
> in the range of [0..0xFFFFFF].

I am aware of this, and it isn't really a problem, adaptors that
allocate randomly across the entire QPN space would not be compatible
with this approach, but most adaptors allocate QPNs
quasi-contiguously.

Basically, at startup, IPoIB would allocate a TX QP, then allocate TSS
QPs, and throw away any that can't fit in the encoding, until it
reaches the target number or tries too long. No need for a special API
to the driver.

Jason
--
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

  parent reply	other threads:[~2013-04-30 16:28 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-04-15 13:21 [PATCH V4 for-next 1/5] IB/core: Add RSS and TSS QP groups - suggesting BOF during OFA conf to further discuss that Or Gerlitz
     [not found] ` <CAJZOPZLVyYODJ=z6KDfx0UJtaHpA7nUt2kwadEugpV1LWxhEMw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-04-22 16:46   ` Or Gerlitz
     [not found]     ` <CAJZOPZKwH66uEukqDSvV+4-z+RhroOB1a0AiWBvdq7D3mso7gQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-04-23 21:15       ` Or Gerlitz
     [not found]         ` <CAJZOPZL1eminwg+MVAC+8y4Pg3Nff=aeMN9ic57SB3cRAg8Hnw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-04-24  2:24           ` Hefty, Sean
     [not found]             ` <1828884A29C6694DAF28B7E6B8A823736FD1E64F-P5GAC/sN6hkd3b2yrw5b5LfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2013-04-25 20:12               ` Jason Gunthorpe
     [not found]                 ` <20130425201255.GB31863-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2013-04-25 20:26                   ` Hefty, Sean
     [not found]                     ` <1828884A29C6694DAF28B7E6B8A823736FD1EF16-P5GAC/sN6hkd3b2yrw5b5LfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2013-04-25 20:43                       ` Jason Gunthorpe
     [not found]                         ` <20130425204357.GD31863-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2013-04-25 20:56                           ` Or Gerlitz
     [not found]                             ` <CAJZOPZK8hcfm2OCnsJkhCiRNxOFXOB0xc9i7tmB4qEnkXrXC0Q-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-04-25 21:40                               ` Jason Gunthorpe
     [not found]                                 ` <20130425214058.GF31863-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2013-04-29 19:49                                   ` Or Gerlitz
2013-04-29 19:52                                   ` Or Gerlitz
     [not found]                                     ` <CAJZOPZLMtoxYyQO24F5_2Gr7ye0AFPQ5aZHp4dZFu1LQFK_cYg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-04-29 20:36                                       ` Jason Gunthorpe
     [not found]                                         ` <20130429203653.GA25804-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2013-04-30  9:04                                           ` Shlomo Pongratz
     [not found]                                             ` <517F8919.8060108-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
2013-04-30 16:28                                               ` Jason Gunthorpe [this message]
2013-04-30 20:14                                           ` Or Gerlitz
2013-04-29 19:56                                   ` Or Gerlitz
2013-04-30 20:09                                   ` Or Gerlitz
     [not found]                                 ` <CAJZOPZL9Zrd+5z+pN8UNPwYFu5fg2x5=3hyNDO_EekA+4QQQNA@mail.gmail.com>
     [not found]                                   ` <CAJZOPZL9Zrd+5z+pN8UNPwYFu5fg2x5=3hyNDO_EekA+4QQQNA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-04-30 20:27                                     ` Jason Gunthorpe

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=20130430162841.GA29903@obsidianresearch.com \
    --to=jgunthorpe-epgobjl8dl3ta4ec/59zmfatqe2ktcn/@public.gmane.org \
    --cc=cl-vYTEC60ixJUAvxtiuMwx3w@public.gmane.org \
    --cc=linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=or.gerlitz-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
    --cc=sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org \
    --cc=shlomop-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org \
    --cc=tzahio-VPRAkNaXOzVWk0Htik3J/w@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