Re: [PATCH rdma-next 00/14] Cleanup locking and events in ucma

From: Jason Gunthorpe
Date: Thu Aug 27 2020 - 11:14:32 EST


On Tue, Aug 18, 2020 at 03:05:12PM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@xxxxxxxxxx>
>
> >From Jason:
>
> Rework how the uevents for new connections are handled so all the locking
> ends up simpler and a work queue can be removed. This should also speed up
> destruction of ucma_context's as a flush_workqueue() was replaced with
> cancel_work_sync().
>
> The simpler locking comes from narrowing what file->mut covers and moving
> other data to other locks, particularly by injecting the handler_mutex
> from the RDMA CM core as a construct available to ULPs. The handler_mutex
> directly prevents handlers from running without creating any ABBA locking
> problems.
>
> Fix various error cases and data races caused by missing locking.
>
> Thanks
>
> Jason Gunthorpe (14):
> RDMA/ucma: Fix refcount 0 incr in ucma_get_ctx()
> RDMA/ucma: Remove unnecessary locking of file->ctx_list in close
> RDMA/ucma: Consolidate the two destroy flows
> RDMA/ucma: Fix error cases around ucma_alloc_ctx()
> RDMA/ucma: Remove mc_list and rely on xarray
> RDMA/cma: Add missing locking to rdma_accept()
> RDMA/ucma: Do not use file->mut to lock destroying
> RDMA/ucma: Fix the locking of ctx->file
> RDMA/ucma: Fix locking for ctx->events_reported
> RDMA/ucma: Add missing locking around rdma_leave_multicast()
> RDMA/ucma: Change backlog into an atomic
> RDMA/ucma: Narrow file->mut in ucma_event_handler()
> RDMA/ucma: Rework how new connections are passed through event
> delivery
> RDMA/ucma: Remove closing and the close_wq

Applied to for-next

Jason