[ofa-general] Re: multiple threads posting to the same QP

[Or Gerlitz]

Dotan Barak wrote:
> Or Gerlitz wrote:
>> Dotan, is there any mentioning of multiple thread scheme in the 
>> libibverbs/librdmacm man pages?

> As much as i know, libibverbs is a fully thread safe library.
> I checked the code of the mthca and i noticed a spin lock before posting 
> (SR or RR), so everything should be o.k. if you post from different threads in 
> parallel .

So the locking should be provided by the low-level per device library? 
if this is the case, I fail to see this documented anywhere.

Also do we actually want locking in the fast posting path? for example 
is it legal to call send(2) on the same socket fd from two threads?

> I didn't add any "thread" text in the man pages yet.
> If you think that it is required, i will add it somewhere (i can add a 
> new man file verbs.h.3 that will specify this).

I suggest we first resolve it with Roland and then see what/how to 
document this.

btw, I think it would be very helpful for users if there would be a 
general man page to libibverbs, similar to the rdma_cm(7) page provided 
by the librdmacm-util package

Or.