Size the queue depth based on the ringbuffer size. Also accomodate for the fact that we could have multiple channels (ringbuffers) per adaptor.
Signed-off-by: K. Y. Srinivasan <k...@microsoft.com> Reviewed-by: Long Li <lon...@microsoft.com> --- drivers/scsi/storvsc_drv.c | 27 ++++++++++++++++----------- 1 files changed, 16 insertions(+), 11 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 27fe850..5a12897 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -309,10 +309,15 @@ enum storvsc_request_type { */ static int storvsc_ringbuffer_size = (256 * PAGE_SIZE); +static u32 max_outstanding_req_per_channel; + +static int storvsc_vcpus_per_sub_channel = 4; module_param(storvsc_ringbuffer_size, int, S_IRUGO); MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)"); +module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO); +MODULE_PARM_DESC(vcpus_per_sub_channel, "Ratio of VCPUs to subchannels"); /* * Timeout in seconds for all devices managed by this driver. */ @@ -320,7 +325,6 @@ static int storvsc_timeout = 180; static int msft_blist_flags = BLIST_TRY_VPD_PAGES; -#define STORVSC_MAX_IO_REQUESTS 200 static void storvsc_on_channel_callback(void *context); @@ -1376,7 +1380,6 @@ static int storvsc_do_io(struct hv_device *device, static int storvsc_device_configure(struct scsi_device *sdevice) { - scsi_change_queue_depth(sdevice, STORVSC_MAX_IO_REQUESTS); blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE); @@ -1646,7 +1649,6 @@ static struct scsi_host_template scsi_driver = { .eh_timed_out = storvsc_eh_timed_out, .slave_configure = storvsc_device_configure, .cmd_per_lun = 255, - .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS, .this_id = -1, /* no use setting to 0 since ll_blk_rw reset it to 1 */ /* currently 32 */ @@ -1686,6 +1688,7 @@ static int storvsc_probe(struct hv_device *device, const struct hv_vmbus_device_id *dev_id) { int ret; + int num_cpus = num_online_cpus(); struct Scsi_Host *host; struct hv_host_device *host_dev; bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false); @@ -1694,6 +1697,7 @@ static int storvsc_probe(struct hv_device *device, int max_luns_per_target; int max_targets; int max_channels; + int max_sub_channels = 0; /* * Based on the windows host we are running on, @@ -1719,12 +1723,18 @@ static int storvsc_probe(struct hv_device *device, max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET; max_targets = STORVSC_MAX_TARGETS; max_channels = STORVSC_MAX_CHANNELS; + /* + * On Windows8 and above, we support sub-channels for storage. + * The number of sub-channels offerred is based on the number of + * VCPUs in the guest. + */ + max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel); break; } - if (dev_id->driver_data == SFC_GUID) - scsi_driver.can_queue = (STORVSC_MAX_IO_REQUESTS * - STORVSC_FC_MAX_TARGETS); + scsi_driver.can_queue = (max_outstanding_req_per_channel * + max_sub_channels + 1); + host = scsi_host_alloc(&scsi_driver, sizeof(struct hv_host_device)); if (!host) @@ -1837,7 +1847,6 @@ static struct hv_driver storvsc_drv = { static int __init storvsc_drv_init(void) { - u32 max_outstanding_req_per_channel; /* * Divide the ring buffer data size (which is 1 page less @@ -1852,10 +1861,6 @@ static int __init storvsc_drv_init(void) vmscsi_size_delta, sizeof(u64))); - if (max_outstanding_req_per_channel < - STORVSC_MAX_IO_REQUESTS) - return -EINVAL; - return vmbus_driver_register(&storvsc_drv); } -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html