From: Denis Joseph Barrow <D.Barow@option•com>
To: Alan Cox <alan@lxorguk•ukuu.org.uk>,
Linux USB kernel mailing list <linux-usb@vger•kernel.org>,
Linux netdev Mailing list <netdev@vger•kernel.org>
Subject: I think I figured out the another bug which manifests itself when low_latency is set to 0
Date: Tue, 13 Jan 2009 11:07:00 +0100 [thread overview]
Message-ID: <496C67C4.4070501@option.com> (raw)
Hi Alan,
Admittedly there always was a bug when tty_insert_flip_string runs out of memory when low_latency is set to 0,
After your change I now
need a callback when tty_insert_flip_string has room for more data & I currently I don't get one,
This is needed to execute the code in hso_unthrottle_tasklet i.e. I do flow control by not submitting
read urbs to the modem when TTY_THROTTLED is set. The only way I can see for getting this callback without modifying the tty layer
is setting the TTY_THROTTLED bit if tty_insert_flip_string returns 0, I hope this works.
I'm personally a bit frightened that we may have more bugs/problems that will manifest by setting low_latency to 0,
especially for the guys here running diagnostics over the serial port requiring very high throughput.
--
best regards,
D.J. Barrow
Linux Kernel Developer
Option NV, Gaston Geenslaan 14, 3001 Leuven, Belgium
T: +32 16 311 621
F: +32 16 207 164
d.barow@option•com
www.option.com
Disclaimer:
http://www.option.com/company/disclaimer.shtml
reply other threads:[~2009-01-13 10:07 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=496C67C4.4070501@option.com \
--to=d.barow@option$(echo .)com \
--cc=alan@lxorguk$(echo .)ukuu.org.uk \
--cc=linux-usb@vger$(echo .)kernel.org \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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