Leak in rdma_get_cm_event on pthread_cancel?

When I want to stop the thread reading rdma events, I kill it with a pthread_cancel(), since it is blocked in a rdma_get_cm_event(). This causes a leak of the evt variable in the rdma_get_cm_event() function. Not a big deal, of
course, but a couple of pthread_cleanup_push(free, evt) and pthread_cleanup_pop() should solve it.

Quoted 6 lines

When I want to stop the thread reading rdma events, I kill it with a pthread_cancel(), since it is blocked in a rdma_get_cm_event(). This causes a leak of the evt variable in the rdma_get_cm_event() function. Not a big deal, of
course, but a couple of pthread_cleanup_push(free, evt) and pthread_cleanup_pop() should solve it.

What version of the librdmacm are you using?

When I want to stop the thread reading rdma events, I kill it with a pthread_cancel(), since it is blocked in a rdma_get_cm_event(). This causes a leak of the evt variable in the rdma_get_cm_event() function. Not a big deal, of course, but a couple of pthread_cleanup_push(free, evt) and pthread_cleanup_pop() should solve it.

Quoted 6 lines

When I want to stop the thread reading rdma events, I kill it with a pthread_cancel(), since it is blocked in a rdma_get_cm_event(). This causes a leak of the evt variable in the rdma_get_cm_event() function. Not a big deal, of course, but a couple of pthread_cleanup_push(free, evt) and pthread_cleanup_pop() should solve it.

None of the IB libraries have been audited for posix async cancellation safety.

To do this work someone would have to review every call to determine if it is a cancelation point, and document this as part of the API.

Then review if any of the internal cancelation points in the cancelable functions require a resource clean up, and add it.

IHMO, cancelation should not be used with threads that call into the ib libraries.

Jason

what is then the proper way to stop a thread blocked on rdma_get_cm_event() (or on ibv_get_cq_event())?

Quoted 2 lines · Flavio Baronti

what is then the proper way to stop a thread blocked on rdma_get_cm_event() (or on ibv_get_cq_event())?

Oh, this is simple - don't get there... have your code

1. get the FDs associated with IB - which you can retrieve from librdmacm and from libibverbs

2. make them non blocking

3. add them to you select/poll FD group

Quoted 9 lines

Quoted 2 lines · Flavio Baronti

what is then the proper way to stop a thread blocked on rdma_get_cm_event() (or on ibv_get_cq_event())?

Oh, this is simple - don't get there... have your code

1. get the FDs associated with IB - which you can retrieve from librdmacm and from libibverbs

Quoted 3 lines

2. make them non blocking

3. add them to you select/poll FD group

4. Use an eventfd or otherwise to break out of the select/poll loop and then exit your thread.

Jason