Messages in this thread | ![/](/images/icornerl.gif) | | Date | Fri, 4 Jul 2003 11:36:49 -0700 | From | William Lee Irwin III <> | Subject | Re: 2.5.74-mm1 fails to boot due to APIC trouble, 2.5.73mm3 works. |
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At some point in the past, zwane wrote: >> The way i see it is that you can't use NR_CPUS to determine the upper >> bound on APIC IDs. e.g. my 3way is normally configured with NR_CPUS = 3 >> but has APIC IDs of 0, 3 and 4. We need to make a distinction.
On Fri, Jul 04, 2003 at 09:18:12AM -0700, Martin J. Bligh wrote: > Fair enough. But that would seem to be a simpler operation than this patch.
It is not a simpler operation. It is the patch.
On Fri, Jul 04, 2003 at 09:18:12AM -0700, Martin J. Bligh wrote: > We break it out in subarch, but it's the same everywhere, which seems > utterly useless - is probably historical cruft that needs to die. > But that sounds like a separate issue, and a separate patch to me.
The change is correct. Let it stand.
On Fri, Jul 04, 2003 at 09:18:12AM -0700, Martin J. Bligh wrote: > Ugh, are you saying the cpumask stuff shrinks masks to < 32 bits if > NR_CPUS is low enough? If so, I can see more point to the patch, but > it still seems like violent overkill. Stopping it doing that would > probably fix it ... I can't imagine it buys you much.
This change is also correct. Let it stand.
On Fri, Jul 04, 2003 at 09:18:12AM -0700, Martin J. Bligh wrote: > phys_cpu_present_map started off as an unsigned long, and I reused it > in a fairly twisted way for NUMA-Q. As it's an array that's bounded > by apic space, using the bios_cpu_apicid method that summit uses > would be a much cleaner fix, and just leave the old one as a long > bitmask like it used to be - which is fine for non- clustered apic > systems, and saves inventing a whole new data type. See the > cpu_present_to_apicid abstraction.
The precise thing this does is making phys_cpu_present_map an array bounded by the APIC space. The change is correct. Let it stand.
At some point in the past, zwane wrote: >> Urgh, it's really hard to determine what these functions really want half >> the time. But that change does look wrong.
On Fri, Jul 04, 2003 at 09:18:12AM -0700, Martin J. Bligh wrote: > Yeah, things taking logical apicids, and turning them into cpu numbers > presumably shouldn't have to touch that.
The cpu bitmasks change width with NR_CPUS. The APIC ID spaces do not. They must hence be bitmasks of separate widths. Hence the change is correct. Let it stand.
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