From: Denis Kenzior <denkenz at gmail.com>
To: ell at lists.01.org
Subject: Re: [PATCH] dhcp,dhcp6,icmp6,time: Convert timestamps to CLOCK_BOOTTIME
Date: Wed, 18 May 2022 09:19:30 -0500 [thread overview]
Message-ID: <11b132ac-4069-88a6-ddfb-e68a570b810f@gmail.com> (raw)
In-Reply-To: 20220518003523.1717565-1-andrew.zaborowski@intel.com
[-- Attachment #1: Type: text/plain, Size: 1260 bytes --]
Hi Andrew,
On 5/17/22 19:35, Andrew Zaborowski wrote:
> The frame reception timestamps obtained for DHCPv4, DHCPv6 and ICMPv6
> frames from the kernel are based on CLOCK_REALTIME, there's no option to
> switch them to CLOCK_BOOTTIME, which we use across our retransmission and
> renew logic. Add a time-private.h utility to convert the timestamps
> right where we read them from recvmsg() to produce CLOCK_BOOTTIME based
> times. This isn't 100% bulletproof because the offset between the two
> clocks can vary between the time the frame was received by the kernel and
> the time we read the offset. The probability is very low though and we
> have no better solution at this time other than fixing it in the kernel.
> Using CLOCK_REALTIME for frame reception timestamps seems to mainly
> create potential for problems in the common usages.
>
> Fixes: c78ad1bb6d7e ("dhcp: Set lease expiry based on frame reception times")
> ---
> ell/dhcp-transport.c | 3 ++-
> ell/dhcp6-transport.c | 5 +++--
> ell/icmp6.c | 2 +-
> ell/time-private.h | 1 +
> ell/time.c | 34 ++++++++++++++++++++++++++++++++++
> 6 files changed, 44 insertions(+), 6 deletions(-)
>
Applied, thanks.
Regards,
-Denis
next reply other threads:[~2022-05-18 14:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-18 14:19 Denis Kenzior [this message]
-- strict thread matches above, loose matches on Subject: below --
2022-05-18 14:22 [PATCH] dhcp,dhcp6,icmp6,time: Convert timestamps to CLOCK_BOOTTIME Denis Kenzior
2022-05-18 0:35 Andrew Zaborowski
2022-05-18 0:22 [PATCH] dhcp, dhcp6, icmp6, time: " Andrew Zaborowski
2022-05-17 23:29 Andrew Zaborowski
2022-05-17 14:37 [PATCH] dhcp,dhcp6,icmp6,time: " Denis Kenzior
2022-05-16 21:31 Andrew Zaborowski
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