On 01/28/2015 11:53 PM, Meelis Roos wrote:
On Mon, 24 Nov 2014, David Miller wrote:
From: mroos@xxxxxxxx
Date: Tue, 25 Nov 2014 00:23:20 +0200 (EET)
Yes, that does look like the case. Do you have a good trick on how
to allocate a map for the highest possible cpu number without first
iterating the cpu map? I couldn't find something that looks like a
highest_possible_cpu() helper.
Honestly I think that num_posible_cpus() should return the max of
number of CPUs (weigt), and the highest numbered CPU. It's a pain in
the butt to handle this otherwise.
Hear, hear!!! That would make my life easier, and would make this sort
of problem much less likely to occur!
How about this one?
It make the machine work.
Thanks for testing!
What's the status of this fix? It is still not applied on yesterdays
3.19.0-rc6-00105-gc59c961 git...
Hmm, I thought commit a33c1ba29138 took care of it... Does the attached
work?
--
Jens Axboe
diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c
index 5f13f4d0bcce..527d315dc1a5 100644
--- a/block/blk-mq-cpumap.c
+++ b/block/blk-mq-cpumap.c
@@ -88,10 +88,11 @@ int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues)
unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set)
{
unsigned int *map;
+ size_t sz;
/* If cpus are offline, map them to first hctx */
- map = kzalloc_node(sizeof(*map) * nr_cpu_ids, GFP_KERNEL,
- set->numa_node);
+ sz = max_t(unsigned int, nr_cpu_ids, num_possible_cpus());
+ map = kzalloc_node(sizeof(*map) * sz, GFP_KERNEL, set->numa_node);
if (!map)
return NULL;
