From: David Miller <davem@davemloft.net>
To: jdmason@kudzu.us
Cc: netdev@vger.kernel.org
Subject: Re: [net-next PATCH 1/3] vxge: always enable hardware time stamp
Date: Tue, 12 Apr 2011 11:01:51 -0700 (PDT) [thread overview]
Message-ID: <20110412.110151.71117421.davem@davemloft.net> (raw)
In-Reply-To: <20110412153604.GA1433@kudzu.us>
From: Jon Mason <jdmason@kudzu.us>
Date: Tue, 12 Apr 2011 10:36:06 -0500
> On Sun, Apr 10, 2011 at 06:58:45PM -0700, David Miller wrote:
>> From: Jon Mason <jdmason@kudzu.us>
>> Date: Fri, 8 Apr 2011 16:11:21 -0500
>>
>> > Hardware time stamp calculation can only be enabled by the privileged
>> > function. Enable it always by default and simply use the ethtool
>> > interface to set a flag to indicate whether or not the respective
>> > function driver should indicate the timestamp along with the received
>> > packet.
>> >
>> > Also, make certain fields in vxge_hw_device_config bit-fields to reduce
>> > the size of the struct.
>> >
>> > Signed-off-by: Jon Mason <jdmason@kudzu.us>
>>
>> Doesn't this have some performance or latency impact?
>
> It is all done in hardware by replacing the CRC with the HWTS value.
> So, no perf or latency issues there. It still only handles the HWTS
> in receive if it is enabled in software via the ioctl.
Ok, thanks for the clarification, I'll apply this patch set.
prev parent reply other threads:[~2011-04-12 18:02 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-08 21:11 [net-next PATCH 1/3] vxge: always enable hardware time stamp Jon Mason
2011-04-11 1:58 ` David Miller
2011-04-12 15:36 ` Jon Mason
2011-04-12 18:01 ` David Miller [this message]
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=20110412.110151.71117421.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=jdmason@kudzu.us \
--cc=netdev@vger.kernel.org \
/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).