From: "Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>
To: "Martinez, Ricardo" <ricardo.martinez@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Netdev <netdev@vger.kernel.org>,
linux-wireless@vger.kernel.org, kuba@kernel.org,
davem@davemloft.net, johannes@sipsolutions.net,
ryazanov.s.a@gmail.com, loic.poulain@linaro.org,
m.chetan.kumar@intel.com, chandrashekar.devegowda@intel.com,
linuxwwan@intel.com, chiranjeevi.rapolu@linux.intel.com,
haijun.liu@mediatek.com, amir.hanania@intel.com,
dinesh.sharma@intel.com, eliot.lee@intel.com,
mika.westerberg@linux.intel.com, moises.veleta@intel.com,
pierre-louis.bossart@intel.com,
muralidharan.sethuraman@intel.com,
Soumya.Prakash.Mishra@intel.com, sreehari.kancharla@intel.com
Subject: Re: [PATCH net-next v3 01/12] net: wwan: t7xx: Add control DMA interface
Date: Thu, 13 Jan 2022 20:31:19 +0200 (EET) [thread overview]
Message-ID: <27cfde-5885-73d-962d-677e3d3a09f@linux.intel.com> (raw)
In-Reply-To: <61183e27-e83a-81b2-5f86-cedb39a50382@linux.intel.com>
[-- Attachment #1: Type: text/plain, Size: 3576 bytes --]
On Wed, 12 Jan 2022, Martinez, Ricardo wrote:
>
> On 1/12/2022 11:24 AM, Ilpo Järvinen wrote:
> > On Wed, 12 Jan 2022, Martinez, Ricardo wrote:
> >
> > > On 1/12/2022 10:16 AM, Ilpo Järvinen wrote:
> > > > On Wed, 12 Jan 2022, Andy Shevchenko wrote:
> > > >
> > > > > On Wed, Jan 12, 2022 at 04:24:52PM +0200, Ilpo Järvinen wrote:
> > > > > > On Wed, 12 Jan 2022, Andy Shevchenko wrote:
> > > > > > > On Tue, Jan 11, 2022 at 08:55:58PM -0800, Martinez, Ricardo wrote:
> > > > > > > > On 12/16/2021 3:08 AM, Ilpo Järvinen wrote:
> > > > > > > > > On Mon, 6 Dec 2021, Ricardo Martinez wrote:
> > > > > > > > > > + if (req->entry.next == &ring->gpd_ring)
> > > > > > > > > > + return list_first_entry(&ring->gpd_ring,
> > > > > > > > > > struct
> > > > > > > > > > cldma_request, entry);
> > > > > > > > > > +
> > > > > > > > > > + return list_next_entry(req, entry);
> > > > > > > ...
> > > > > > >
> > > > > > > > > > + if (req->entry.prev == &ring->gpd_ring)
> > > > > > > > > > + return list_last_entry(&ring->gpd_ring, struct
> > > > > > > > > > cldma_request, entry);
> > > > > > > > > > +
> > > > > > > > > > + return list_prev_entry(req, entry);
> > > > > > > ...
> > > > > > >
> > > > > > > > > Wouldn't these two seems generic enough to warrant adding
> > > > > > > > > something like
> > > > > > > > > list_next/prev_entry_circular(...) to list.h?
> > > > > > > > Agree, in the upcoming version I'm planning to include something
> > > > > > > > like this
> > > > > > > > to list.h as suggested:
> > > > > > > I think you mean for next and prev, i.o.w. two helpers, correct?
> > > > > > >
> > > > > > > > #define list_next_entry_circular(pos, ptr, member) \
> > > > One thing I missed earlier, the sigrature should instead of ptr have
> > > > head:
> > > > #define list_next_entry_circular(pos, head, member)
> > > >
> > > > > > > > ((pos)->member.next == (ptr) ? \
> > > > > > > I believe this is list_entry_is_head().
> > > > > > It takes .next so it's not the same as list_entry_is_head() and
> > > > > > list_entry_is_last() doesn't exist.
> > > > > But we have list_last_entry(). So, what about
> > > > >
> > > > > list_last_entry() == pos ? first : next;
> > > > >
> > > > > and counterpart
> > > > >
> > > > > list_first_entry() == pos ? last : prev;
> > > > >
> > > > > ?
> > > > Yes, although now that I think it more, using them implies the head
> > > > element has to be always accessed. It might be marginally cache
> > > > friendlier
> > > > to use list_entry_is_head you originally suggested but get the next
> > > > entry
> > > > first:
> > > > ({
> > > > typeof(pos) next__ = list_next_entry(pos, member); \
> > > > !list_entry_is_head(next__, head, member) ? next__ :
> > > > list_next_entry(next__, member);
> > > > })
> > > > (This was written directly to email, entirely untested).
> > > >
> > > > Here, the head element would only get accessed when we really need to
> > > > walk
> > > > through it.
> > > I'm not sure if list_next_entry() will work for the last element, what
> > > about
> > > using list_is_last()?
> > Why wouldn't it? E.g., list_for_each_entry() does it for the last entry
> > before terminating the for loop.
>
> I wasn't sure about using container_of() on the head of the list, but I see
> that it is not a problem.
>
> Would that still be preferred over the list_is_last() approach?
I think list_is_last() is fine if that's what you want to use.
...I missed earlier the fact that you were referring to something else
than list_entry_is_last thanks to these n similarly named functions :-).
--
i.
next prev parent reply other threads:[~2022-01-13 18:34 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-07 2:46 [PATCH net-next v3 00/12] net: wwan: t7xx: PCIe driver for MediaTek M.2 modem Ricardo Martinez
2021-12-07 2:47 ` [PATCH net-next v3 01/12] net: wwan: t7xx: Add control DMA interface Ricardo Martinez
2021-12-07 17:11 ` Jakub Kicinski
2021-12-16 11:08 ` Ilpo Järvinen
2022-01-12 4:55 ` Martinez, Ricardo
2022-01-12 11:40 ` Andy Shevchenko
2022-01-12 14:24 ` Ilpo Järvinen
2022-01-12 16:20 ` Andy Shevchenko
2022-01-12 18:16 ` Ilpo Järvinen
2022-01-12 19:03 ` Martinez, Ricardo
2022-01-12 19:24 ` Ilpo Järvinen
2022-01-12 20:08 ` Martinez, Ricardo
2022-01-13 18:31 ` Ilpo Järvinen [this message]
2021-12-07 2:47 ` [PATCH net-next v3 02/12] net: wwan: t7xx: Add core components Ricardo Martinez
2021-12-16 11:55 ` Ilpo Järvinen
2022-01-12 21:58 ` Martinez, Ricardo
2021-12-07 2:47 ` [PATCH net-next v3 03/12] net: wwan: t7xx: Add port proxy infrastructure Ricardo Martinez
2021-12-16 12:17 ` Ilpo Järvinen
2021-12-07 2:47 ` [PATCH net-next v3 04/12] net: wwan: t7xx: Add control port Ricardo Martinez
2021-12-16 13:44 ` Ilpo Järvinen
2021-12-07 2:47 ` [PATCH net-next v3 05/12] net: wwan: t7xx: Add AT and MBIM WWAN ports Ricardo Martinez
2021-12-07 9:48 ` Loic Poulain
2021-12-16 12:25 ` Ilpo Järvinen
2021-12-16 12:59 ` Andy Shevchenko
2021-12-07 2:47 ` [PATCH net-next v3 06/12] net: wwan: t7xx: Data path HW layer Ricardo Martinez
2021-12-07 11:59 ` Andy Shevchenko
2021-12-07 12:04 ` Andy Shevchenko
2021-12-07 2:47 ` [PATCH net-next v3 07/12] net: wwan: t7xx: Add data path interface Ricardo Martinez
2021-12-16 13:30 ` Ilpo Järvinen
2022-01-12 23:27 ` Martinez, Ricardo
2021-12-07 2:47 ` [PATCH net-next v3 08/12] net: wwan: t7xx: Add WWAN network interface Ricardo Martinez
2021-12-07 2:47 ` [PATCH net-next v3 09/12] net: wwan: t7xx: Introduce power management support Ricardo Martinez
2021-12-07 2:47 ` [PATCH net-next v3 10/12] net: wwan: t7xx: Runtime PM Ricardo Martinez
2021-12-07 2:47 ` [PATCH net-next v3 11/12] net: wwan: t7xx: Device deep sleep lock/unlock Ricardo Martinez
2021-12-07 2:47 ` [PATCH net-next v3 12/12] net: wwan: t7xx: Add maintainers and documentation Ricardo Martinez
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=27cfde-5885-73d-962d-677e3d3a09f@linux.intel.com \
--to=ilpo.jarvinen@linux.intel.com \
--cc=Soumya.Prakash.Mishra@intel.com \
--cc=amir.hanania@intel.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=chandrashekar.devegowda@intel.com \
--cc=chiranjeevi.rapolu@linux.intel.com \
--cc=davem@davemloft.net \
--cc=dinesh.sharma@intel.com \
--cc=eliot.lee@intel.com \
--cc=haijun.liu@mediatek.com \
--cc=johannes@sipsolutions.net \
--cc=kuba@kernel.org \
--cc=linux-wireless@vger.kernel.org \
--cc=linuxwwan@intel.com \
--cc=loic.poulain@linaro.org \
--cc=m.chetan.kumar@intel.com \
--cc=mika.westerberg@linux.intel.com \
--cc=moises.veleta@intel.com \
--cc=muralidharan.sethuraman@intel.com \
--cc=netdev@vger.kernel.org \
--cc=pierre-louis.bossart@intel.com \
--cc=ricardo.martinez@linux.intel.com \
--cc=ryazanov.s.a@gmail.com \
--cc=sreehari.kancharla@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 read-only IMAP folder(s) and NNTP newsgroup(s).