Messages in this thread | | | Date | Fri, 13 Jul 2007 00:08:14 -0700 (PDT) | Subject | Re: x86: Convert cpu_core_map to be a per cpu variable | From | David Miller <> |
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From: Christoph Lameter <clameter@sgi.com> Date: Thu, 12 Jul 2007 23:58:06 -0700 (PDT)
> cpu_core_map is currently an array defined using NR_CPUS. This means that > we overallocate since we will rarely really use the maximum > number of configured cpus. This may become a problem when we need to > increase the NR_CPUs on x86_64 for our new product line.
I'm using NR_CPUS set to 1024 on my sparc64 workstation, it's not that bad to be honest :-) What kind of cpu arity are you talking about?
> If we put the cpu_core_map into the per cpu area then it will be allocated > for each processor as it comes online. > > However, this means that the core map cannot be accessed until the per cpu > area has been allocated. Xen does a weird thing here looping over all > processors and zeroing the masks that are not yet allocated and that will > be zeroed when they are allocated. I commented the code out. Maybe there > is another purpose? Jeremy? > > Signed-off-by: Christoph Lameter <clameter@sgi.com>
Please take care of sparc64 if you're going to do this change. It uses cpu_core_map too. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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