diff options
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 72 | ||||
| -rw-r--r-- | include/linux/hyperv.h | 5 |
2 files changed, 48 insertions, 29 deletions
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index c3eba37db9b7..4506a6623618 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -370,25 +370,27 @@ static const struct hv_vmbus_device_id hp_devs[] = { /* * We use this state to statically distribute the channel interrupt load. */ -static u32 next_vp; +static int next_numa_node_id; /* * Starting with Win8, we can statically distribute the incoming - * channel interrupt load by binding a channel to VCPU. We - * implement here a simple round robin scheme for distributing - * the interrupt load. - * We will bind channels that are not performance critical to cpu 0 and - * performance critical channels (IDE, SCSI and Network) will be uniformly - * distributed across all available CPUs. + * channel interrupt load by binding a channel to VCPU. + * We do this in a hierarchical fashion: + * First distribute the primary channels across available NUMA nodes + * and then distribute the subchannels amongst the CPUs in the NUMA + * node assigned to the primary channel. + * + * For pre-win8 hosts or non-performance critical channels we assign the + * first CPU in the first NUMA node. */ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_guid) { u32 cur_cpu; int i; bool perf_chn = false; - u32 max_cpus = num_online_cpus(); - struct vmbus_channel *primary = channel->primary_channel, *prev; - unsigned long flags; + struct vmbus_channel *primary = channel->primary_channel; + int next_node; + struct cpumask available_mask; for (i = IDE; i < MAX_PERF_CHN; i++) { if (!memcmp(type_guid->b, hp_devs[i].guid, @@ -405,36 +407,48 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui * Also if the channel is not a performance critical * channel, bind it to cpu 0. */ + channel->numa_node = 0; + cpumask_set_cpu(0, &channel->alloced_cpus_in_node); channel->target_cpu = 0; channel->target_vp = hv_context.vp_index[0]; return; } /* - * Primary channels are distributed evenly across all vcpus we have. - * When the host asks us to create subchannels it usually makes us - * num_cpus-1 offers and we are supposed to distribute the work evenly - * among the channel itself and all its subchannels. Make sure they are - * all assigned to different vcpus. + * We distribute primary channels evenly across all the available + * NUMA nodes and within the assigned NUMA node we will assign the + * first available CPU to the primary channel. + * The sub-channels will be assigned to the CPUs available in the + * NUMA node evenly. */ - if (!primary) - cur_cpu = (++next_vp % max_cpus); - else { + if (!primary) { + while (true) { + next_node = next_numa_node_id++; + if (next_node == nr_node_ids) + next_node = next_numa_node_id = 0; + if (cpumask_empty(cpumask_of_node(next_node))) + continue; + break; + } + channel->numa_node = next_node; + primary = channel; + } + + if (cpumask_weight(&primary->alloced_cpus_in_node) == + cpumask_weight(cpumask_of_node(primary->numa_node))) { /* - * Let's assign the first subchannel of a channel to the - * primary->target_cpu+1 and all the subsequent channels to - * the prev->target_cpu+1. + * We have cycled through all the CPUs in the node; + * reset the alloced map. */ - spin_lock_irqsave(&primary->lock, flags); - if (primary->num_sc == 1) - cur_cpu = (primary->target_cpu + 1) % max_cpus; - else { - prev = list_prev_entry(channel, sc_list); - cur_cpu = (prev->target_cpu + 1) % max_cpus; - } - spin_unlock_irqrestore(&primary->lock, flags); + cpumask_clear(&primary->alloced_cpus_in_node); } + cpumask_xor(&available_mask, &primary->alloced_cpus_in_node, + cpumask_of_node(primary->numa_node)); + + cur_cpu = cpumask_next(-1, &available_mask); + cpumask_set_cpu(cur_cpu, &primary->alloced_cpus_in_node); + channel->target_cpu = cur_cpu; channel->target_vp = hv_context.vp_index[cur_cpu]; } diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 4317cd1b69ed..30d3a1f79450 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -697,6 +697,11 @@ struct vmbus_channel { /* The corresponding CPUID in the guest */ u32 target_cpu; /* + * State to manage the CPU affiliation of channels. + */ + struct cpumask alloced_cpus_in_node; + int numa_node; + /* * Support for sub-channels. For high performance devices, * it will be useful to have multiple sub-channels to support * a scalable communication infrastructure with the host. |