diff options
Diffstat (limited to 'drivers/scsi/storvsc_drv.c')
| -rw-r--r-- | drivers/scsi/storvsc_drv.c | 90 |
1 files changed, 72 insertions, 18 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 5f2d177c3bd9..d3897c438448 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -395,6 +395,12 @@ MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)"); module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO); MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels"); + +static int ring_avail_percent_lowater = 10; +module_param(ring_avail_percent_lowater, int, S_IRUGO); +MODULE_PARM_DESC(ring_avail_percent_lowater, + "Select a channel if available ring size > this in percent"); + /* * Timeout in seconds for all devices managed by this driver. */ @@ -468,6 +474,13 @@ struct storvsc_device { * Mask of CPUs bound to subchannels. */ struct cpumask alloced_cpus; + /* + * Pre-allocated struct cpumask for each hardware queue. + * struct cpumask is used by selecting out-going channels. It is a + * big structure, default to 1024k bytes when CONFIG_MAXSMP=y. + * Pre-allocate it to avoid allocation on the kernel stack. + */ + struct cpumask *cpumask_chns; /* Used for vsc/vsp channel reset process */ struct storvsc_cmd_request init_request; struct storvsc_cmd_request reset_request; @@ -872,6 +885,13 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc) if (stor_device->stor_chns == NULL) return -ENOMEM; + stor_device->cpumask_chns = kcalloc(num_possible_cpus(), + sizeof(struct cpumask), GFP_KERNEL); + if (stor_device->cpumask_chns == NULL) { + kfree(stor_device->stor_chns); + return -ENOMEM; + } + stor_device->stor_chns[device->channel->target_cpu] = device->channel; cpumask_set_cpu(device->channel->target_cpu, &stor_device->alloced_cpus); @@ -1232,6 +1252,7 @@ static int storvsc_dev_remove(struct hv_device *device) vmbus_close(device->channel); kfree(stor_device->stor_chns); + kfree(stor_device->cpumask_chns); kfree(stor_device); return 0; } @@ -1241,7 +1262,7 @@ static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device, { u16 slot = 0; u16 hash_qnum; - struct cpumask alloced_mask; + struct cpumask *alloced_mask = &stor_device->cpumask_chns[q_num]; int num_channels, tgt_cpu; if (stor_device->num_sc == 0) @@ -1257,10 +1278,10 @@ static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device, * III. Mapping is persistent. */ - cpumask_and(&alloced_mask, &stor_device->alloced_cpus, + cpumask_and(alloced_mask, &stor_device->alloced_cpus, cpumask_of_node(cpu_to_node(q_num))); - num_channels = cpumask_weight(&alloced_mask); + num_channels = cpumask_weight(alloced_mask); if (num_channels == 0) return stor_device->device->channel; @@ -1268,7 +1289,7 @@ static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device, while (hash_qnum >= num_channels) hash_qnum -= num_channels; - for_each_cpu(tgt_cpu, &alloced_mask) { + for_each_cpu(tgt_cpu, alloced_mask) { if (slot == hash_qnum) break; slot++; @@ -1285,9 +1306,9 @@ static int storvsc_do_io(struct hv_device *device, { struct storvsc_device *stor_device; struct vstor_packet *vstor_packet; - struct vmbus_channel *outgoing_channel; + struct vmbus_channel *outgoing_channel, *channel; int ret = 0; - struct cpumask alloced_mask; + struct cpumask *alloced_mask; int tgt_cpu; vstor_packet = &request->vstor_packet; @@ -1301,22 +1322,53 @@ static int storvsc_do_io(struct hv_device *device, /* * Select an an appropriate channel to send the request out. */ - if (stor_device->stor_chns[q_num] != NULL) { outgoing_channel = stor_device->stor_chns[q_num]; - if (outgoing_channel->target_cpu == smp_processor_id()) { + if (outgoing_channel->target_cpu == q_num) { /* * Ideally, we want to pick a different channel if * available on the same NUMA node. */ - cpumask_and(&alloced_mask, &stor_device->alloced_cpus, + alloced_mask = &stor_device->cpumask_chns[q_num]; + cpumask_and(alloced_mask, &stor_device->alloced_cpus, cpumask_of_node(cpu_to_node(q_num))); - for_each_cpu_wrap(tgt_cpu, &alloced_mask, - outgoing_channel->target_cpu + 1) { - if (tgt_cpu != outgoing_channel->target_cpu) { - outgoing_channel = - stor_device->stor_chns[tgt_cpu]; - break; + + for_each_cpu_wrap(tgt_cpu, alloced_mask, q_num + 1) { + if (tgt_cpu == q_num) + continue; + channel = stor_device->stor_chns[tgt_cpu]; + if (hv_get_avail_to_write_percent( + &channel->outbound) + > ring_avail_percent_lowater) { + outgoing_channel = channel; + goto found_channel; + } + } + + /* + * All the other channels on the same NUMA node are + * busy. Try to use the channel on the current CPU + */ + if (hv_get_avail_to_write_percent( + &outgoing_channel->outbound) + > ring_avail_percent_lowater) + goto found_channel; + + /* + * If we reach here, all the channels on the current + * NUMA node are busy. Try to find a channel in + * other NUMA nodes + */ + cpumask_andnot(alloced_mask, &stor_device->alloced_cpus, + cpumask_of_node(cpu_to_node(q_num))); + + for_each_cpu(tgt_cpu, alloced_mask) { + channel = stor_device->stor_chns[tgt_cpu]; + if (hv_get_avail_to_write_percent( + &channel->outbound) + > ring_avail_percent_lowater) { + outgoing_channel = channel; + goto found_channel; } } } @@ -1324,7 +1376,7 @@ static int storvsc_do_io(struct hv_device *device, outgoing_channel = get_og_chn(stor_device, q_num); } - +found_channel: vstor_packet->flags |= REQUEST_COMPLETION_FLAG; vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) - @@ -1726,8 +1778,9 @@ static int storvsc_probe(struct hv_device *device, max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel); } - scsi_driver.can_queue = (max_outstanding_req_per_channel * - (max_sub_channels + 1)); + scsi_driver.can_queue = max_outstanding_req_per_channel * + (max_sub_channels + 1) * + (100 - ring_avail_percent_lowater) / 100; host = scsi_host_alloc(&scsi_driver, sizeof(struct hv_host_device)); @@ -1858,6 +1911,7 @@ err_out2: err_out1: kfree(stor_device->stor_chns); + kfree(stor_device->cpumask_chns); kfree(stor_device); err_out0: |