lkml.org 
[lkml]   [2015]   [Apr]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 04/28] IB/Verbs: Reform IB-core cm


On 04/13/2015 08:12 PM, ira.weiny wrote:
[snip]
>> -
>> - if (rdma_node_get_transport(ib_device->node_type) != RDMA_TRANSPORT_IB)
>> - return;
>> + int count = 0;
>
> I'm ok with this as an intermediate patch but going forward if we are going to
> have calls like
>
> static inline int cap_ib_cm_dev(struct ib_device *device)

Actually I really don't want to introduce this kind of helper, it's slow, ugly
and break the consistency, but I can't find a good way to avoid that...

For example the check inside cma_listen_on_dev(), how could we do per-port check
while don't even know which port will be used later...

>
> Then I think we should have similar calls like
>
> cap_ib_mad_dev(device)
>
> Which eliminates the clean up below...

I'd like to avoid using such helper as long as possible :-P

>
>>
>> cm_dev = kzalloc(sizeof(*cm_dev) + sizeof(*port) *
>> ib_device->phys_port_cnt, GFP_KERNEL);
>> @@ -3783,6 +3781,9 @@ static void cm_add_one(struct ib_device *ib_device)
>>
>> set_bit(IB_MGMT_METHOD_SEND, reg_req.method_mask);
>> for (i = 1; i <= ib_device->phys_port_cnt; i++) {
>> + if (!rdma_ib_or_iboe(ib_device, i))
>> + continue;
>> +
>> port = kzalloc(sizeof *port, GFP_KERNEL);
>> if (!port)
>> goto error1;
>> @@ -3809,7 +3810,16 @@ static void cm_add_one(struct ib_device *ib_device)
>> ret = ib_modify_port(ib_device, i, 0, &port_modify);
>> if (ret)
>> goto error3;
>> +
>> + count++;
>> }
>> +
>> + if (!count) {
>> + device_unregister(cm_dev->device);
>> + kfree(cm_dev);
>> + return;
>
> Here.
>
> I worry about mistakes being made when we loop through only to find that none
> of the ports support the feature and then we have to clean up. As this is
> initialization code I don't see any issue with looping through the ports 2
> times and making the code cleaner.

This style of logical could be found in other core module too, may be keep
consistent is not a bad idea?

After all, it's just initialization code which relatively rarely used :-)

Regards,
Michael Wang

>
> This applies to the SA and CM modules as well.
>
> However, in the ib_cm module you already have cap_ib_cm_dev(device) so you
> should use it at the start of cm_add_one.
>
> Ira
>


\
 
 \ /
  Last update: 2015-04-14 10:21    [W:0.107 / U:1.396 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site