From: skannan@codeaurora.org (Saravana Kannan)
To: linux-arm-kernel@lists.infradead.org
Subject: udelay() broken for SMP cores?
Date: Tue, 20 Apr 2010 23:43:23 -0700 [thread overview]
Message-ID: <4BCE9E8B.2070103@codeaurora.org> (raw)
In-Reply-To: <EAF47CD23C76F840A9E7FCE10091EFAB02C4FEED81@dbde02.ent.ti.com>
>> I looked at arch/arm/lib/delay.S and it looks like __udelay and
>> __const_udelay won't work correctly for SMP cores. The code just uses
>> the loops_per_jiffy variable instead of the per-CPU loops per jiffy data.
>>
>> Is anyone already working on a fix for that? If not, I can fix it up in
>> a way that's hopefully palatable to the community.
>
> If you have case where individual CPUs are running at different speed and different
> Tick rate then only this can make difference.
Yes. I was talking about the case where the CPUs could be running at
different speeds.
Thanks,
Saravana
next prev parent reply other threads:[~2010-04-21 6:43 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-21 2:19 udelay() broken for SMP cores? Saravana Kannan
2010-04-21 4:56 ` Shilimkar, Santosh
2010-04-21 6:43 ` Saravana Kannan [this message]
2010-04-21 7:22 ` Russell King - ARM Linux
2010-04-21 9:39 ` skannan at codeaurora.org
2010-04-21 9:50 ` Russell King - ARM Linux
2010-04-21 9:58 ` Gilles Chanteperdrix
2010-04-21 10:00 ` Jamie Lokier
2010-04-21 19:29 ` Russell King - ARM Linux
2010-04-21 19:52 ` Jamie Lokier
2010-04-21 20:21 ` Russell King - ARM Linux
2010-04-21 20:47 ` Jamie Lokier
2010-04-21 20:57 ` Russell King - ARM Linux
2010-04-22 0:14 ` Jamie Lokier
2011-01-08 23:24 ` Russell King - ARM Linux
2010-04-21 10:31 ` skannan at codeaurora.org
2010-04-21 19:33 ` Russell King - ARM Linux
2010-04-21 23:47 ` Saravana Kannan
2010-04-23 9:00 ` Pavel Machek
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