| Message ID | 20210602212144.17799-2-tim.gardner@canonical.com |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: storvsc: Parameterize number hardware queues | expand |
On 02/06/2021 22:21, Tim Gardner wrote: > From: "Melanie Plageman (Microsoft)" <melanieplageman@gmail.com> > > BugLink: https://bugs.launchpad.net/bugs/1930626 > > Add ability to set the number of hardware queues with new module parameter, > storvsc_max_hw_queues. The default value remains the number of CPUs. This > functionality is useful in some environments (e.g. Microsoft Azure) where > decreasing the number of hardware queues has been shown to improve > performance. > > Link: https://lore.kernel.org/r/20210224232948.4651-1-melanieplageman@gmail.com > Reviewed-by: Michael Kelley <mikelley@microsoft.com> > Signed-off-by: Melanie Plageman (Microsoft) <melanieplageman@gmail.com> > Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> > (cherry picked from commit a81a38cc6ddaf128c7ca9e3fffff21c243f33c97) > Signed-off-by: Tim Gardner <tim.gardner@canonical.com> > --- > drivers/scsi/storvsc_drv.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > index e416a6064158..b97561eae671 100644 > --- a/drivers/scsi/storvsc_drv.c > +++ b/drivers/scsi/storvsc_drv.c > @@ -378,10 +378,14 @@ static u32 max_outstanding_req_per_channel; > static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth); > > static int storvsc_vcpus_per_sub_channel = 4; > +static unsigned int storvsc_max_hw_queues; > > module_param(storvsc_ringbuffer_size, int, S_IRUGO); > MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)"); > > +module_param(storvsc_max_hw_queues, uint, 0644); > +MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues"); > + > module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO); > MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels"); > > @@ -1897,6 +1901,7 @@ static int storvsc_probe(struct hv_device *device, > { > int ret; > int num_cpus = num_online_cpus(); > + int num_present_cpus = num_present_cpus(); > struct Scsi_Host *host; > struct hv_host_device *host_dev; > bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false); > @@ -2010,8 +2015,17 @@ static int storvsc_probe(struct hv_device *device, > * For non-IDE disks, the host supports multiple channels. > * Set the number of HW queues we are supporting. > */ > - if (!dev_is_ide) > - host->nr_hw_queues = num_present_cpus(); > + if (!dev_is_ide) { > + if (storvsc_max_hw_queues > num_present_cpus) { > + storvsc_max_hw_queues = 0; > + storvsc_log(device, STORVSC_LOGGING_WARN, > + "Resetting invalid storvsc_max_hw_queues value to default.\n"); > + } > + if (storvsc_max_hw_queues) > + host->nr_hw_queues = storvsc_max_hw_queues; > + else > + host->nr_hw_queues = num_present_cpus; > + } > > /* > * Set the error handler work queue. > Acked-by: Colin Ian King <colin.king@canonical.com>
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index e416a6064158..b97561eae671 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -378,10 +378,14 @@ static u32 max_outstanding_req_per_channel; static int storvsc_change_queue_depth(struct scsi_device *sdev, int queue_depth); static int storvsc_vcpus_per_sub_channel = 4; +static unsigned int storvsc_max_hw_queues; module_param(storvsc_ringbuffer_size, int, S_IRUGO); MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)"); +module_param(storvsc_max_hw_queues, uint, 0644); +MODULE_PARM_DESC(storvsc_max_hw_queues, "Maximum number of hardware queues"); + module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO); MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels"); @@ -1897,6 +1901,7 @@ static int storvsc_probe(struct hv_device *device, { int ret; int num_cpus = num_online_cpus(); + int num_present_cpus = num_present_cpus(); struct Scsi_Host *host; struct hv_host_device *host_dev; bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false); @@ -2010,8 +2015,17 @@ static int storvsc_probe(struct hv_device *device, * For non-IDE disks, the host supports multiple channels. * Set the number of HW queues we are supporting. */ - if (!dev_is_ide) - host->nr_hw_queues = num_present_cpus(); + if (!dev_is_ide) { + if (storvsc_max_hw_queues > num_present_cpus) { + storvsc_max_hw_queues = 0; + storvsc_log(device, STORVSC_LOGGING_WARN, + "Resetting invalid storvsc_max_hw_queues value to default.\n"); + } + if (storvsc_max_hw_queues) + host->nr_hw_queues = storvsc_max_hw_queues; + else + host->nr_hw_queues = num_present_cpus; + } /* * Set the error handler work queue.