[PATCH 4/7] nvme-fc: don't override opts->nr_io_queues

[James Smart]

On 7/2/2017 1:10 AM, Sagi Grimberg wrote:
>
>
> On 29/06/17 18:11, James Smart wrote:
>> On 6/29/2017 4:09 AM, Sagi Grimberg wrote:
>>> Its what the user passed, so its probably a better
>>> idea to keep it intact. Also, limit the number of
>>> I/O queues to max online cpus as blk-mq doesnt know
>>> how to handle more anyhow.
>>>
>>> Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
>>> ---
>>>   drivers/nvme/host/fc.c | 14 +++++++++-----
>>>   1 file changed, 9 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
>>> index 2f990d979037..5ee821d9cb75 100644
>>> --- a/drivers/nvme/host/fc.c
>>> +++ b/drivers/nvme/host/fc.c
>>> @@ -2175,17 +2175,19 @@ static int
>>>   nvme_fc_create_io_queues(struct nvme_fc_ctrl *ctrl)
>>>   {
>>>       struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
>>> +    unsigned int nr_io_queues;
>>>       int ret;
>>> -    ret = nvme_set_queue_count(&ctrl->ctrl, &opts->nr_io_queues);
>>> +    nr_io_queues = min(opts->nr_io_queues, num_online_cpus());
>>
>> I had assumed the check vs online cpu count was done in fabrics.c - 
>> but as we're talking about a later reconnect, the cpu count may have 
>> changed, so this looks good.
>>
>> however, the snippet obsoletes the "min_t(unsigned int, 
>> opts->nr_io_queues, lport->ops->max_hw_queues)" that was done in the 
>> next snippet.
>
> Not unless we min against it again (which we could, what's your
> preference?)

please add a line to min it against it again.

-- james