netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Florian Fainelli <f.fainelli@gmail.com>
To: Eric Dumazet <edumazet@google.com>
Cc: songliubraving@fb.com, Alexei Starovoitov <ast@fb.com>,
	netdev <netdev@vger.kernel.org>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
	Alexander Duyck <alexander.h.duyck@intel.com>,
	michael.chan@broadcom.com, kernel-team <Kernel-team@fb.com>
Subject: Re: pegged softirq and NAPI race (?)
Date: Tue, 18 Sep 2018 14:35:46 -0700	[thread overview]
Message-ID: <db210de6-1e7d-3b3d-8f6f-33f80d11f863@gmail.com> (raw)
In-Reply-To: <CANn89iLzFhXS77T=Hu6SSrL5NR+VqvDwX3AXDxhSy15aCUEWMw@mail.gmail.com>

On 09/18/2018 02:28 PM, Eric Dumazet wrote:
> On Tue, Sep 18, 2018 at 2:25 PM Florian Fainelli <f.fainelli@gmail.com> wrote:
>>
>>
>> This would not be the only driver doing this unfortunately... should we
>> add a __must_check annotation to help catch those (mis)uses? Though that
>> could cause false positives for drivers using NAPI to clean their TX ring.
>>
> 
> Well, before adding __must_check we would need to cook a (big) patch
> series to change all occurrences.
> 

Sounds good, I don't mind submitting something unless you beat me to it.

> 
> Not clear why netpoll is the trigger ?
> 

Me either, this should be observable during normal operation as well,
though most likely you just get a spurious interrupt and nothing to
clean in the RX ring, so things just get unnoticed?
-- 
Florian

  reply	other threads:[~2018-09-19  3:10 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-18  8:41 pegged softirq and NAPI race (?) Song Liu
2018-09-18 13:45 ` Eric Dumazet
2018-09-18 16:19   ` Song Liu
2018-09-18 16:31     ` Rik van Riel
2018-09-18 16:33     ` Eric Dumazet
2018-09-18 16:49       ` Song Liu
2018-09-18 17:51   ` Alexei Starovoitov
2018-09-18 18:17     ` Eric Dumazet
2018-09-18 20:37       ` Song Liu
2018-09-18 21:13         ` Eric Dumazet
2018-09-18 21:21           ` Eric Dumazet
2018-09-18 21:36             ` Jeff Kirsher
2018-09-18 21:40               ` Song Liu
2018-09-18 21:46                 ` Eric Dumazet
2018-09-18 21:55                   ` Song Liu
2018-09-18 22:04                     ` Eric Dumazet
2018-09-18 21:21           ` Song Liu
2018-09-18 21:25             ` Eric Dumazet
2018-09-18 21:25           ` Florian Fainelli
2018-09-18 21:28             ` Eric Dumazet
2018-09-18 21:35               ` Florian Fainelli [this message]
2018-09-18 21:36               ` Song Liu

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=db210de6-1e7d-3b3d-8f6f-33f80d11f863@gmail.com \
    --to=f.fainelli@gmail.com \
    --cc=Kernel-team@fb.com \
    --cc=alexander.h.duyck@intel.com \
    --cc=ast@fb.com \
    --cc=edumazet@google.com \
    --cc=jeffrey.t.kirsher@intel.com \
    --cc=michael.chan@broadcom.com \
    --cc=netdev@vger.kernel.org \
    --cc=songliubraving@fb.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).