From: "Dewar, Alan" <ad759e@intl.att.com>
To: "'Dumitrescu, Cristian'" <cristian.dumitrescu@intel.com>,
"'alangordondewar@gmail.com'" <alangordondewar@gmail.com>
Cc: "'dev@dpdk.org'" <dev@dpdk.org>,
"'Alan Dewar'" <alan.dewar@att.com>,
"'Kantecki, Tomasz'" <tomasz.kantecki@intel.com>,
"'Singh, Jasvinder'" <jasvinder.singh@intel.com>
Subject: Re: [dpdk-dev] [PATCH v5] sched: make RED scaling configurable
Date: Mon, 15 Jan 2018 15:36:22 +0000 [thread overview]
Message-ID: <3F9268EEC0E43747A5FFFC6B48EF0321FC1018@gbcdcmbx03.intl.att.com> (raw)
In-Reply-To: <3EB4FA525960D640B5BDFFD6A3D891267BAFC364@IRSMSX108.ger.corp.intel.com>
> > > > > diff --git a/lib/librte_sched/rte_red.c
> > > > > b/lib/librte_sched/rte_red.c
> > > > > +int
> > > > > +rte_red_set_scaling(uint16_t max_red_queue_length) {
> > > > > + int8_t count;
> > > > > +
> > > > > + if (rte_red_init_done)
> > > > > + /**
> > > > > + * Can't change the scaling once the red table has been
> > > > > + * computed.
> > > > > + */
> > > > > + return -1;
> > > >
> > > > Is there a reason why we cannot simply reset the scaling here?
> > >
> > > Actually we could, but I was originally thinking that you might be
> > > happier keeping with a one-time RED initialization function, but
> > > then had to introduce the rte_reset_red_scaling function for the
> > > unit-tests. I'm happy
> > to
> > > do RED reinitialization here, if you are.
> > >
> >
> > Hi Alan,
> >
> > What is the intention of the new rte_red_set_scaling() function?
> > 1. Is it to be called only once, before any RED object gets created?
> > 2. Is it possible to call it post-init, but in this case any RED
> > object already created are not impacted (they continue to work)?
> >
> > If the answer is 2, then yes, we could simply drop the
> > __rte_red_reset() and do the RED globals reset as part of the
> > rte_red_set_scaling() function transparently.
> >
> > If the answer is 1, then we probably need to keep your approach: we
> > need a global rte_red_init_done flag, and rte_red_set_scaling() could
> > only be called at init time before any red objects are created.
> >
> > I probably need to spend more time assessing all the code implications.
> >
> > Regards,
> > Cristian
>
> Hi Alan,
>
> After talking to Tomasz, we agreed that 2. Is not an option, as any previously created red object will be broken.
>
> So 1. Is the right answer, therefore this function can be called only once and only before any red objects are created. So, IMO we should do this:
-when rte_red_init_done is true, we need to return error -when rte_red_init_done is false, we need to perform red initialization and set this flag
>
> Agree?
Yes, as long as you're happy with keeping __rte_red_reset for the unit-tests.
> Please also add a comment in the Doxygen description of rte_red_set_caling() in the rte_red.h file, stating that this function can be called only once and only before any red objects are created.
Will do.
> Regards,
> Cristian
next prev parent reply other threads:[~2018-01-15 15:36 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1507022514-21831-1>
2018-01-08 15:27 ` alangordondewar
2018-01-11 13:11 ` Dumitrescu, Cristian
2018-01-12 9:38 ` Dewar, Alan
2018-01-12 11:09 ` Dumitrescu, Cristian
2018-01-12 11:52 ` Dumitrescu, Cristian
2018-01-15 15:36 ` Dewar, Alan [this message]
2018-01-16 11:56 ` Dumitrescu, Cristian
2018-01-12 10:44 ` Dewar, Alan
2018-01-12 11:43 ` Dumitrescu, Cristian
2018-01-15 16:16 ` [dpdk-dev] [PATCH v6] " alangordondewar
2018-01-15 16:52 ` Stephen Hemminger
2018-01-16 15:50 ` Alan Dewar
2018-01-16 15:57 ` Alan Dewar
2018-01-16 16:44 ` Dumitrescu, Cristian
2018-01-16 16:07 ` [dpdk-dev] [PATCH v7] " alangordondewar
2019-04-05 15:36 ` Ferruh Yigit
2019-04-05 15:36 ` Ferruh Yigit
2019-04-08 8:24 ` Alan Dewar
2019-04-08 8:24 ` Alan Dewar
2019-04-08 8:53 ` Thomas Monjalon
2019-04-08 8:53 ` Thomas Monjalon
2019-04-08 13:29 ` Dumitrescu, Cristian
2019-04-08 13:29 ` Dumitrescu, Cristian
2020-07-06 23:09 ` Thomas Monjalon
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=3F9268EEC0E43747A5FFFC6B48EF0321FC1018@gbcdcmbx03.intl.att.com \
--to=ad759e@intl.att.com \
--cc=alan.dewar@att.com \
--cc=alangordondewar@gmail.com \
--cc=cristian.dumitrescu@intel.com \
--cc=dev@dpdk.org \
--cc=jasvinder.singh@intel.com \
--cc=tomasz.kantecki@intel.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).