From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Gerd Knorr <kraxel@bytesex.org>
Cc: "Randy.Dunlap" <rddunlap@osdl.org>,
rmk@arm.linux.org.uk,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: reducing stack usage in v4l?
Date: 11 Mar 2003 16:29:30 +0000 [thread overview]
Message-ID: <1047400169.19262.3.camel@irongate.swansea.linux.org.uk> (raw)
In-Reply-To: <20030311091934.GB20721@bytesex.org>
On Tue, 2003-03-11 at 09:19, Gerd Knorr wrote
> That is wrong, at least the 2k memset/call mentioned by Andrew. There
> are lots of memset() calls, but they all are within the case switches
> for the ioctls and zero out only the structs which are used in that code
> path, so it is actually much smaller (~50 -> ~300 bytes maybe, depending
> on the ioctl).
gcc sometimes does things like allocate all the objects in case
statements at entry time. I assume its a performance win to do so.
Alan
next prev parent reply other threads:[~2003-03-11 15:11 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-03-05 5:25 Randy.Dunlap
2003-03-05 5:43 ` Andrew Morton
2003-03-05 9:15 ` Gerd Knorr
2003-03-05 9:35 ` Russell King
2003-03-05 15:34 ` Randy.Dunlap
2003-03-05 21:40 ` Jörn Engel
2003-03-11 4:27 ` Randy.Dunlap
2003-03-11 9:19 ` Gerd Knorr
2003-03-11 16:29 ` Alan Cox [this message]
2003-03-11 15:36 ` Daniel Jacobowitz
2003-03-05 11:50 ` mdew
2003-03-05 12:28 ` Gerd Knorr
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=1047400169.19262.3.camel@irongate.swansea.linux.org.uk \
--to=alan@lxorguk.ukuu.org.uk \
--cc=kraxel@bytesex.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rddunlap@osdl.org \
--cc=rmk@arm.linux.org.uk \
/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
all inboxes | Powered by JetHome®