From: Oliver Neukum <oliver@neukum.org>
To: linux-usb-devel@lists.sourceforge.net
Cc: Eduardo Pereira Habkost <ehabkost@mandriva.com>,
Greg KH <gregkh@suse.de>,
Luiz Fernando Capitulino <lcapitulino@mandriva.com.br>,
linux-kernel@vger.kernel.org
Subject: Re: [linux-usb-devel] Re: [PATCH 00/10] usb-serial: Switches from spin lock to atomic_t.
Date: Tue, 6 Dec 2005 23:48:14 +0100 [thread overview]
Message-ID: <200512062348.14349.oliver@neukum.org> (raw)
In-Reply-To: <20051206201340.GB20451@duckman.conectiva>
Am Dienstag, 6. Dezember 2005 21:13 schrieb Eduardo Pereira Habkost:
> Anyway, I don't see yet why the atomic_t would make the code slower on
> non-smp. Is atomic_add_unless(v, 1, 1) supposed to be slower than
> 'if (!v) v = 1;' ?
spin_lock() can be dropped on UP. atomic_XXX must either use an operation
on main memory, meaning less efficient code generation, or must disable
interrupts even on UP.
Regards
Oliver
next prev parent reply other threads:[~2005-12-06 22:48 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-12-06 11:56 Luiz Fernando Capitulino
2005-12-06 19:40 ` Greg KH
2005-12-06 20:13 ` Eduardo Pereira Habkost
2005-12-06 22:48 ` Oliver Neukum [this message]
2005-12-07 12:24 ` [linux-usb-devel] " Luiz Fernando Capitulino
2005-12-07 12:27 ` Arjan van de Ven
2005-12-07 12:30 ` Luiz Fernando Capitulino
2005-12-07 12:34 ` Arjan van de Ven
2005-12-07 12:41 ` Luiz Fernando Capitulino
2005-12-07 12:54 ` Luiz Fernando Capitulino
2005-12-07 15:07 ` Alan Stern
2005-12-07 15:22 ` Arjan van de Ven
2005-12-07 15:37 ` Oliver Neukum
2005-12-07 15:40 ` Arjan van de Ven
2005-12-07 15:50 ` Oliver Neukum
2005-12-07 16:02 ` Alan Cox
2005-12-07 16:00 ` Eduardo Pereira Habkost
2005-12-07 16:02 ` Arjan van de Ven
2005-12-07 16:23 ` Eduardo Pereira Habkost
2005-12-07 16:01 ` Alan Stern
2005-12-07 16:04 ` Arjan van de Ven
2005-12-07 15:32 ` linux-os (Dick Johnson)
2005-12-07 16:08 ` Alan Stern
2005-12-06 20:14 ` Luiz Fernando Capitulino
2005-12-06 21:02 ` Pete Zaitcev
2005-12-06 21:18 ` Luiz Fernando Capitulino
2005-12-06 22:36 ` [linux-usb-devel] " Oliver Neukum
2005-12-07 12:25 ` Luiz Fernando Capitulino
2005-12-07 13:01 ` Oliver Neukum
2005-12-07 13:17 ` Luiz Fernando Capitulino
2005-12-07 16:41 ` Greg KH
2005-12-07 16:51 ` Luiz Fernando Capitulino
2005-12-07 17:13 ` Eduardo Pereira Habkost
2005-12-07 17:56 ` Greg KH
2005-12-07 19:10 ` Eduardo Pereira Habkost
2005-12-07 16:55 ` Otavio Salvador
2005-12-07 16:59 ` Greg KH
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=200512062348.14349.oliver@neukum.org \
--to=oliver@neukum.org \
--cc=ehabkost@mandriva.com \
--cc=gregkh@suse.de \
--cc=lcapitulino@mandriva.com.br \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb-devel@lists.sourceforge.net \
/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®