Re: [PATCH rdma-next v2 13/17] RDMA/core: Get sum value of all counters when perform a sysfs stat read

[Leon Romanovsky <leon@kernel.org>]

On Thu, May 30, 2019 at 06:01:46AM +0000, Mark Zhang wrote:
> On 5/29/2019 11:44 PM, Jason Gunthorpe wrote:
> > On Wed, May 29, 2019 at 02:05:24PM +0300, Leon Romanovsky wrote:
> >> On Wed, May 22, 2019 at 02:26:36PM -0300, Jason Gunthorpe wrote:
> >>> On Mon, Apr 29, 2019 at 11:34:49AM +0300, Leon Romanovsky wrote:
> >>>> diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
> >>>> index c56ffc61ab1e..8ae4906a60e7 100644
> >>>> +++ b/drivers/infiniband/core/device.c
> >>>> @@ -1255,7 +1255,11 @@ int ib_register_device(struct ib_device *device, const char *name)
> >>>>   		goto dev_cleanup;
> >>>>   	}
> >>>>
> >>>> -	rdma_counter_init(device);
> >>>> +	ret = rdma_counter_init(device);
> >>>> +	if (ret) {
> >>>> +		dev_warn(&device->dev, "Couldn't initialize counter\n");
> >>>> +		goto sysfs_cleanup;
> >>>> +	}
> >>>
> >>> Don't put this things randomly, if there is some reason it should be
> >>> after sysfs it needs a comment, otherwise if it is just allocating
> >>> memory it belongs earlier, and the unwind should be done in release.
> >>>
> >>> I also think it is very strange/wrong that both sysfs and counters are
> >>> allocating the same alloc_hw_stats object
> >>>
> >>> Why can't they share?
> >>
> >> They can, but we wanted to separate "legacy" counters which were exposed
> >> through sysfs and "new" counters which can be enabled/disable automatically.
> >
> > Is there any cross contamination through the hw_stats? If no they
> > should just share. >
>
> sysfs hw_stats holds the port counter, while this one holds the
> history value of all dynamically allocated counters. They can not share.
> port_counter =
>    default_counter + running_dynamic_counter + history_dynamic_counter

I'm not saying that it is right thing to do, but nothing prevents from you
to add extra field to port_counter exactly for that.

Thanks

>
> > Jason
> >
>