Hello Bharata,
On Thu, 11 Aug 2005, Bharata B Rao wrote:
> I don't know the context of your work here, but a couple of
> observations.
>
> Since you populate cpu_possible_map with NR_CPUS, alloc_percpu()
> would end up allocating for all NR_CPUS. Wouldn't you have achieved
> the same thing by compile time allocation ? Wouldn't this change
> lead to NR_CPUS allocations from alloc_percpu() for all users ?
The patch has been modified (courtesy Andi Kleen) to do something a bit
smarter and only allocate for detected cpus in MADT or MP table. But my
prime concern was that for_each_cpu didn't work at all during boot.
> Now since you have separated cpu_possible_map from cpu_callout_map,
> do we need to reflect cpu_possible_map with the value from
> cpu_callout_map after the cpu_callout_map is initialized fully from
> smp_prepare_cpus().
This should be taken care of using above.
> BTW, I am working on Kiran's dynamic percpu allocator patch and making
> it cpu hotplug aware. With that, alloc_percpu would initially allocate
> only for the possible cpus and would allocate for other cpus as and when
> they come up.
Great, that takes care of my concerns regarding processors which aren't
enumerated during smp boot.
Thanks for the feedback,
Zwane
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
| |
 |