===================================================================
@@ -312,6 +312,15 @@ static struct spu *aff_ref_location(stru
*/
node = cpu_to_node(raw_smp_processor_id());
for (n = 0; n < MAX_NUMNODES; n++, node++) {
+ /*
+ * "available_spus" counts how many spus are not potentially
+ * going to be used by other affinity gangs whose reference
+ * context is already in place. Although this code seeks to
+ * avoid having affinity gangs with a summed amount of
+ * contexts bigger than the amount of spus in the node,
+ * this may happen sporadically. In this case, available_spus
+ * becomes negative, which is harmless.
+ */
int available_spus;
node = (node < MAX_NUMNODES) ? node : 0;
@@ -321,12 +330,10 @@ static struct spu *aff_ref_location(stru
available_spus = 0;
mutex_lock(&cbe_spu_info[node].list_mutex);
list_for_each_entry(spu, &cbe_spu_info[node].spus, cbe_list) {
- if (spu->ctx && spu->ctx->gang
- && spu->ctx->aff_offset == 0)
- available_spus -=
- (spu->ctx->gang->contexts - 1);
- else
- available_spus++;
+ if (spu->ctx && spu->ctx->gang && !spu->ctx->aff_offset
+ && spu->ctx->gang->aff_ref_spu)
+ available_spus -= spu->ctx->gang->contexts;
+ available_spus++;
}
if (available_spus < ctx->gang->contexts) {
mutex_unlock(&cbe_spu_info[node].list_mutex);
This patch improves redability of the code responsible for trying to find a node with enough SPUs not committed to other affinity gangs. An additional check is also added, to avoid taking into account gangs that have no SPU affinity. Signed-off-by: Andre Detsch <adetsch@br.ibm.com>