From: Long Li <[email protected]>
Unlike SCSI and FC, we don't use multiple channels for IDE.
Also fix the calculation for sub-channels.
Change log:
v2: Addressed comment on incorrect number of sub-channels.
(Michael Kelley <[email protected]>)
Signed-off-by: Long Li <[email protected]>
---
drivers/scsi/storvsc_drv.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 8c51d628b52e..a2ec0bc9e9fa 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1722,11 +1722,14 @@ static int storvsc_probe(struct hv_device *device,
max_targets = STORVSC_MAX_TARGETS;
max_channels = STORVSC_MAX_CHANNELS;
/*
- * On Windows8 and above, we support sub-channels for storage.
+ * On Windows8 and above, we support sub-channels for storage
+ * on SCSI and FC controllers.
* 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);
+ if (!dev_is_ide)
+ max_sub_channels =
+ (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
}
scsi_driver.can_queue = (max_outstanding_req_per_channel *
--
2.14.1
> -----Original Message-----
> From: [email protected] <[email protected]> On Behalf
> Of Long Li
> Sent: Thursday, March 22, 2018 2:47 PM
> To: KY Srinivasan <[email protected]>; Haiyang Zhang <[email protected]>; Stephen
> Hemminger <[email protected]>; James E . J . Bottomley <[email protected]>;
> Martin K . Petersen <[email protected]>; [email protected]; linux-
> [email protected]; [email protected]
> Cc: Long Li <[email protected]>
> Subject: [PATCH v2] storvsc: Set up correct queue depth values for IDE devices
>
> From: Long Li <[email protected]>
>
> Unlike SCSI and FC, we don't use multiple channels for IDE.
> Also fix the calculation for sub-channels.
>
> Change log:
> v2: Addressed comment on incorrect number of sub-channels.
> (Michael Kelley <[email protected]>)
>
> Signed-off-by: Long Li <[email protected]>
Reviewed-by: Michael Kelley <[email protected]>
> ---
> drivers/scsi/storvsc_drv.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index 8c51d628b52e..a2ec0bc9e9fa 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -1722,11 +1722,14 @@ static int storvsc_probe(struct hv_device *device,
> max_targets = STORVSC_MAX_TARGETS;
> max_channels = STORVSC_MAX_CHANNELS;
> /*
> - * On Windows8 and above, we support sub-channels for storage.
> + * On Windows8 and above, we support sub-channels for storage
> + * on SCSI and FC controllers.
> * 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);
> + if (!dev_is_ide)
> + max_sub_channels =
> + (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
> }
>
> scsi_driver.can_queue = (max_outstanding_req_per_channel *
> --
> 2.14.1
Hi Martin
Can you take a look at the following patch?
Long
> > -----Original Message-----
> > From: [email protected]
> > <[email protected]> On Behalf Of Long Li
> > Sent: Thursday, March 22, 2018 2:47 PM
> > To: KY Srinivasan <[email protected]>; Haiyang Zhang
> > <[email protected]>; Stephen Hemminger
> <[email protected]>;
> > James E . J . Bottomley <[email protected]>; Martin K . Petersen
> > <[email protected]>; [email protected]; linux-
> > [email protected]; [email protected]
> > Cc: Long Li <[email protected]>
> > Subject: [PATCH v2] storvsc: Set up correct queue depth values for IDE
> > devices
> >
> > From: Long Li <[email protected]>
> >
> > Unlike SCSI and FC, we don't use multiple channels for IDE.
> > Also fix the calculation for sub-channels.
> >
> > Change log:
> > v2: Addressed comment on incorrect number of sub-channels.
> > (Michael Kelley <[email protected]>)
> >
> > Signed-off-by: Long Li <[email protected]>
>
> Reviewed-by: Michael Kelley <[email protected]>
>
> > ---
> > drivers/scsi/storvsc_drv.c | 7 +++++--
> > 1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> > index 8c51d628b52e..a2ec0bc9e9fa 100644
> > --- a/drivers/scsi/storvsc_drv.c
> > +++ b/drivers/scsi/storvsc_drv.c
> > @@ -1722,11 +1722,14 @@ static int storvsc_probe(struct hv_device
> *device,
> > max_targets = STORVSC_MAX_TARGETS;
> > max_channels = STORVSC_MAX_CHANNELS;
> > /*
> > - * On Windows8 and above, we support sub-channels for
> storage.
> > + * On Windows8 and above, we support sub-channels for
> storage
> > + * on SCSI and FC controllers.
> > * 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);
> > + if (!dev_is_ide)
> > + max_sub_channels =
> > + (num_cpus - 1) /
> storvsc_vcpus_per_sub_channel;
> > }
> >
> > scsi_driver.can_queue = (max_outstanding_req_per_channel *
> > --
> > 2.14.1
Long,
> Can you take a look at the following patch?
>> > + max_sub_channels =
>> > + (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
What happens if num_cpus = 1?
--
Martin K. Petersen Oracle Linux Engineering
> Subject: Re: [PATCH v2] storvsc: Set up correct queue depth values for IDE
> devices
>
>
> Long,
>
> > Can you take a look at the following patch?
>
> >> > + max_sub_channels =
> >> > + (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
>
> What happens if num_cpus = 1?
If num_cpus=1, we don't have any sub channels.
The host offers one sub channel for VM with 5 CPUs, after that it offers an additional sub channel every 4 CPUs.
The primary channel is always offered.
>
> --
> Martin K. Petersen Oracle Linux Engineering
Long,
> If num_cpus=1, we don't have any sub channels.
>
> The host offers one sub channel for VM with 5 CPUs, after that it offers
> an additional sub channel every 4 CPUs.
>
> The primary channel is always offered.
Applied to 4.17/scsi-fixes. Thanks!
--
Martin K. Petersen Oracle Linux Engineering