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From:   Lorenzo Colitti <lorenzo@google.com>
Date:   Wed, 21 Apr 2021 23:40:54 +0900
Message-ID: <CAKD1Yr1TOd1XKFdWK2Wr_Pw2rKciSapCM8ATEirxpCApZZzZmQ@mail.gmail.com>
Subject: Re: [PATCH] hrtimer: Update softirq_expires_next correctly after __hrtimer_get_next_event()
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Greg KH <gregkh@linuxfoundation.org>,
        =?UTF-8?Q?Maciej_=C5=BBenczykowski?= <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,
        =?UTF-8?Q?Maciej_=C5=BBenczykowski?= <maze@google.com>,
        Will Deacon <will@kernel.org>
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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.