Re: [PATCH 05/11] mtip32xx: Set block queue boundary variables

[Jeff Moyer <jmoyer@redhat.com>]

Asai Thambi S P <asamymuthupa@micron.com> writes:

> On 5/30/2012 11:43 PM, Jens Axboe wrote:
>
>> On 05/30/2012 03:42 AM, Asai Thambi S P wrote:
>>>
>>> Set the following block queue boundary variables
>>> 	* max_hw_sectors
>>> 	* max_segment_size
>>> 	* nr_requests
>>>
>>> Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
>>> ---
>>>  drivers/block/mtip32xx/mtip32xx.c |    4 ++++
>>>  1 files changed, 4 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
>>> index 9fe897d..801e70c 100644
>>> --- a/drivers/block/mtip32xx/mtip32xx.c
>>> +++ b/drivers/block/mtip32xx/mtip32xx.c
>>> @@ -3631,7 +3631,11 @@ skip_create_disk:
>>>  	set_bit(QUEUE_FLAG_NONROT, &dd->queue->queue_flags);
>>>  	blk_queue_max_segments(dd->queue, MTIP_MAX_SG);
>>>  	blk_queue_physical_block_size(dd->queue, 4096);
>>> +	blk_queue_max_hw_sectors(dd->queue, 0xffff);
>>> +	blk_queue_max_segment_size(dd->queue, 0x400000);
>>>  	blk_queue_io_min(dd->queue, 4096);
>>> +	dd->queue->nr_requests = 255;
>> 
>> ->nr_requests isn't a boundary variable you set for the queue. It's set
>> by the core bits, or by the user via the sysfs interface.
>> 
>> So you should not touch that from the driver.
>> 
>
> Ok.
>
> I saw scsi lib module changing it, so thought of changing the value close to
> device queue depth.

That's actually a fair point.  What is the device queue depth for this
card?

Cheers,
Jeff