From: Jim Nelson <james4765@cwazy•co.uk>
To: Christoph Hellwig <hch@lst•de>
Cc: linuxppc-dev@ozlabs•org, Brian Gerst <bgerst@didntduck•org>,
paulus@samba•org, linux-kernel@vger•kernel.org
Subject: Re: [PATCH 0/7] ppc: remove cli()/sti() from arch/ppc/*
Date: Wed, 05 Jan 2005 06:19:31 -0500 [thread overview]
Message-ID: <41DBCD43.2000104@cwazy.co.uk> (raw)
In-Reply-To: <20050105092659.GA27103@lst.de>
Christoph Hellwig wrote:
> On Tue, Jan 04, 2005 at 09:44:06PM -0500, Jim Nelson wrote:
>
>>Brian Gerst wrote:
>>
>>
>>>James Nelson wrote:
>>>
>>>
>>>>This series of patches is to remove the last cli()/sti() function
>>>>calls in arch/ppc.
>>>>
>>>>These are the only instances in active code that grep could find.
>>>
>>>
>>>Are you sure none of these need real spinlocks instead of just
>>>disabling interrupts?
>>>
>>>--
>>> Brian Gerst
>>>
>>
>>These are for single-processor systems, mostly evaluation boards and
>>embedded processors. I coudn't find any reference to multiprocessor
>>setups for the processors in question after a peruse of the code or a
>>quick google on the boards in question.
>
>
> think CONFIG_PREEMPT. In either case a spinlock becomes
> lock_irq_disable in the !SMP, !PREEMPT case but it documents the
> intention a whole lot better.
>
> Also you're locking only in a single plpace which is a ***BIG*** warning
> sign. At least look at the other users of the data structure, it's
> extremly likely they'll need locking aswell.
>
Some of the cli() uses were in shutdown and IRQ setup code, where you'd just need
to disable interrupts. There are a few files that will need a more thourough
going-through, however.
I'll start checking those later.
Jim
prev parent reply other threads:[~2005-01-05 11:19 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20050104214048.21749.85722.89116@localhost.localdomain>
2005-01-05 2:19 ` [PATCH 0/7] ppc: remove cli()/sti() from arch/ppc/* Brian Gerst
2005-01-05 2:44 ` Jim Nelson
2005-01-05 9:26 ` Christoph Hellwig
2005-01-05 11:19 ` Jim Nelson [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=41DBCD43.2000104@cwazy.co.uk \
--to=james4765@cwazy$(echo .)co.uk \
--cc=bgerst@didntduck$(echo .)org \
--cc=hch@lst$(echo .)de \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=linuxppc-dev@ozlabs$(echo .)org \
--cc=paulus@samba$(echo .)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