From: Frank Seidel <fseidel@suse.de>
To: Adrian Bunk <bunk@kernel.org>
Cc: Jiri Slaby <jirislaby@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [RFC 13/13] Char: nozomi, cleanup read and write
Date: Mon, 12 Nov 2007 10:43:41 +0100 [thread overview]
Message-ID: <200711121043.42745.fseidel@suse.de> (raw)
In-Reply-To: <20071112075452.GD9771@stusta.de>
On Montag 12 November 2007 08:54:52, you (Adrian Bunk) wrote:
> On Sat, Nov 10, 2007 at 11:04:41PM +0100, Jiri Slaby wrote:
> > Why? Anyway I think this is the case. The body of the then branch is executed at
> > most once, while the else branch each time but last. If you write/read 1002
> > bytes, it means 250:1. ...and it's invoked from interrupt too...
>
> AFAIK there is no well defined semantics whether likely/unlikely means
> 10:1 or 10000:1 that is guaranteed to not change during the next
> 10 years.
>
> Unless there's a measurable difference, it's best to write readable
> C code and simply leave all optimizations to the compiler.
>From my (totally) beginners point of view i would have guessed a chance of
very well below one percent that this condition is true could be called
"unlikely",
but i have to admit this is most probably a much too naive way of thinking,
especially in regards of compiler optimizations.
And in this special case now there are already most calls (about 80 percent)
caught by the switch-case-shortcuts anyway.
So, i'll revert it.
Thanks a lot for your feedback,
Frank
next prev parent reply other threads:[~2007-11-12 9:43 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-09 23:43 [RFC 1/13] Char: nozomi, remove unneded stuff Jiri Slaby
2007-11-09 23:44 ` [RFC 2/13] Char: nozomi, expand some functions Jiri Slaby
2007-11-10 15:41 ` Frank Seidel
2007-11-09 23:44 ` [RFC 3/13] Char: nozomi, fix fail paths Jiri Slaby
2007-11-10 15:41 ` Frank Seidel
2007-11-09 23:45 ` [RFC 4/13] Char: nozomi, tty index cleanup Jiri Slaby
2007-11-10 15:41 ` Frank Seidel
2007-11-10 15:50 ` Jiri Slaby
2007-11-09 23:46 ` [RFC 5/13] Char: nozomi, ioctls cleanup Jiri Slaby
2007-11-10 15:41 ` Frank Seidel
2007-11-09 23:46 ` [RFC 6/13] Char: nozomi, reorder and cleanup probe, remove Jiri Slaby
2007-11-10 15:42 ` Frank Seidel
2007-11-09 23:47 ` [RFC 7/13] Char: nozomi, remove struct irq Jiri Slaby
2007-11-10 15:42 ` Frank Seidel
2007-11-12 15:11 ` Frank Seidel
2007-11-09 23:48 ` [RFC 8/13] Char: nozomi, tty cleanup Jiri Slaby
2007-11-10 15:42 ` Frank Seidel
2007-11-12 18:43 ` Frank Seidel
2007-11-09 23:48 ` [RFC 9/13] Char: nozomi, lock cleanup Jiri Slaby
2007-11-10 15:42 ` Frank Seidel
2007-11-09 23:49 ` [RFC! 10/13] Char: nozomi, fix tty_flip_buffer_push Jiri Slaby
2007-11-10 15:43 ` Frank Seidel
2007-11-09 23:50 ` [RFC 11/13] Char: nozomi, remove unused includes Jiri Slaby
2007-11-10 15:43 ` Frank Seidel
2007-11-09 23:50 ` [RFC 12/13] Char: nozomi, remove void acc char2 char3 more mp mp.c mp.yy m1 nozomi2 proto rej slock1 casts Jiri Slaby
2007-11-10 15:43 ` Frank Seidel
2007-11-09 23:51 ` [RFC 13/13] Char: nozomi, cleanup read and write Jiri Slaby
2007-11-10 15:43 ` Frank Seidel
2007-11-10 16:15 ` Adrian Bunk
2007-11-10 22:04 ` Jiri Slaby
2007-11-11 2:37 ` Frank Seidel
2007-11-11 16:02 ` Frank Seidel
2007-11-12 7:54 ` Adrian Bunk
2007-11-12 9:43 ` Frank Seidel [this message]
2007-11-10 15:41 ` [RFC 1/13] Char: nozomi, remove unneded stuff Frank Seidel
2007-11-10 15:55 ` Jiri Slaby
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=200711121043.42745.fseidel@suse.de \
--to=fseidel@suse.de \
--cc=bunk@kernel.org \
--cc=jirislaby@gmail.com \
--cc=linux-kernel@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.