[PATCH 1/4] arm64: topology: Implement basic CPU topology support

Mark Brown broonie at kernel.org
Mon Feb 10 11:46:47 EST 2014


On Mon, Feb 10, 2014 at 04:22:31PM +0000, Catalin Marinas wrote:
> On Mon, Feb 10, 2014 at 01:02:01PM +0000, Mark Brown wrote:

> > +		if (cpu != cpuid)
> > +			cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
> > +	}
> > +	smp_wmb();

> I now noticed there are a couple of smp_wmb() calls in this patch. What
> are they for?

To be honest I mostly cargo culted them from the ARM implementation; I
did look a bit but didn't fully dig into it - it seemed they were
required to ensure that the updates for the new CPU are visible over all
CPUs.  Vincent?
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20140210/fc8ec600/attachment-0001.sig>


More information about the linux-arm-kernel mailing list