From: Greg KH <gregkh@linuxfoundation.org>
To: Lorenzo Colitti <lorenzo@google.com>
Cc: "Thomas Gleixner" <tglx@linutronix.de>,
"Maciej Żenczykowski" <zenczykowski@gmail.com>,
"Ingo Molnar" <mingo@kernel.org>,
"Anna-Maria Behnsen" <anna-maria@linutronix.de>,
lkml <linux-kernel@vger.kernel.org>,
mikael.beckius@windriver.com,
"Maciej Żenczykowski" <maze@google.com>,
"Will Deacon" <will@kernel.org>
Subject: Re: [PATCH] hrtimer: Update softirq_expires_next correctly after __hrtimer_get_next_event()
Date: Wed, 21 Apr 2021 17:22:30 +0200 [thread overview]
Message-ID: <YIBDNoX7Fzb8B6RH@kroah.com> (raw)
In-Reply-To: <CAKD1Yr1TOd1XKFdWK2Wr_Pw2rKciSapCM8ATEirxpCApZZzZmQ@mail.gmail.com>
On Wed, Apr 21, 2021 at 11:40:54PM +0900, Lorenzo Colitti wrote:
> On Wed, Apr 21, 2021 at 11:08 PM Lorenzo Colitti <lorenzo@google.com> wrote:
> > load the timer will almost never fire since there will always be
> > another packet coming. So the speed of adding/updating the timer is
> > much more important than the accuracy. We will try to move it to
> > timer_list.
>
> ... but actually, that's not acceptable, because AFAICS timer_list
> counts in jiffies so its resolution might be as low as 10ms. It's not
> acceptable to delay network traffic by up to 10ms under load. Not sure
> if there is another timer API that can be used here.
What do other network drivers do? This has to be a common problem, why
is this USB driver somehow unique here?
thanks,
greg k-h
next prev parent reply other threads:[~2021-04-21 15:22 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-13 16:55 [PATCH] hrtimer: Update softirq_expires_next correctly after __hrtimer_get_next_event() Maciej Żenczykowski
2021-04-13 17:14 ` Greg KH
2021-04-14 2:49 ` Lorenzo Colitti
2021-04-15 16:47 ` Thomas Gleixner
2021-04-20 3:12 ` Maciej Żenczykowski
2021-04-20 6:44 ` Thomas Gleixner
2021-04-20 8:15 ` Lorenzo Colitti
2021-04-20 14:19 ` Thomas Gleixner
2021-04-21 14:08 ` Lorenzo Colitti
2021-04-21 14:40 ` Lorenzo Colitti
2021-04-21 15:22 ` Greg KH [this message]
2021-04-22 0:08 ` Thomas Gleixner
2021-04-22 10:07 ` Thomas Gleixner
2021-04-22 14:20 ` Lorenzo Colitti
2021-04-22 15:35 ` Thomas Gleixner
2021-04-26 8:49 ` [PATCH] hrtimer: Avoid double reprogramming in __hrtimer_start_range_ns() Thomas Gleixner
2021-04-26 9:40 ` Peter Zijlstra
2021-04-26 12:25 ` Peter Zijlstra
2021-05-14 19:29 ` Thomas Gleixner
2021-04-26 12:33 ` Thomas Gleixner
2021-04-26 12:40 ` Peter Zijlstra
2021-04-26 14:27 ` Thomas Gleixner
-- strict thread matches above, loose matches on Subject: below --
2021-02-12 13:38 Sv: [PATCH] hrtimer: Interrupt storm on clock_settime Beckius, Mikael
2021-02-23 16:02 ` [PATCH] hrtimer: Update softirq_expires_next correctly after __hrtimer_get_next_event() Anna-Maria Behnsen
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=YIBDNoX7Fzb8B6RH@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=anna-maria@linutronix.de \
--cc=linux-kernel@vger.kernel.org \
--cc=lorenzo@google.com \
--cc=maze@google.com \
--cc=mikael.beckius@windriver.com \
--cc=mingo@kernel.org \
--cc=tglx@linutronix.de \
--cc=will@kernel.org \
--cc=zenczykowski@gmail.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).