Subject: Re: [PATCH rdma-next v2 00/13] DEVX asynchronous events

From: Jason Gunthorpe <[email-masked]>
Date: Wed, 3 Jul 2019 12:29:03 -0300

On Sun, Jun 30, 2019 at 07:23:21PM +0300, Leon Romanovsky wrote:
> From: Leon Romanovsky <[email-masked]>
> 
> Changelog:
>  v1 -> v2:
>  * Added Saeed's ack to net patches
>  * Patch #2:
>   * Fix to gather user asynchronous events on top of kernel events.
>  * Patch #7:
>   * Fix obj_id to be 32 bits.
>  * Patch #8:
>   * Inline async_event_queue applicable fields into devx_async_event_file.
>   * Move to use bitfields in few places rather than flags.
>   * Shorten name of UAPI attribute.
>  * Patch #10:
>   * Use explicitly 'struct file *' instead of void *
>   * Store struct devx_async_event_file * instead of uobj * on the subscription.
>   * Drop 'is_obj_related' and use list_empty instead.
>   * Drop the temp arrays as part of the subscription API and move to simpler logic.
>   * Revise devx_cleanup_subscription() to be success oriented without
>     the is_close flag.
>   * Leave key level 1 in the tree upon bad flow to prevent a race with IRQ flow.
>   * Fix some styling notes.
>  * Patch #11:
>   * Use rcu read lock also for the un-affiliated event flow.
>   * Improve locking scheme as part of read events.
>   * Return -EIO as soon as destroyed occurred.
>   * Use a better errno as part read event failure when the buffer size
>     was too small.
>   * Upon hot unplug call wake_up_interruptible() unconditionally.
>   * Use eqe->data for affiliated events header.
>   * Fix some styling notes.
>  * Patch #12:
>   * Use rcu read lock also for the first XA layer.
>  * Patch #13:
>   * A new patch to clean up mdev usage from devx code, it can be accessed
>     from ib_dev now.
>  v0 -> v1:
>  * Fix the unbind / hot unplug flows to work properly.
>  * Fix Ref count handling on the eventfd mode in some flow.
>  * Rebased to latest rdma-next
> 
> Thanks
> 
> >From Yishai:
> 
> This series enables RDMA applications that use the DEVX interface to
> subscribe and read device asynchronous events.
> 
> The solution is designed to allow extension of events in the future
> without need to perform any changes in the driver code.
> 
> To enable that few changes had been done in mlx5_core, it includes:
>  * Reading device event capabilities that are user related
>    (affiliated and un-affiliated) and set the matching mask upon
>    creating the matching EQ.
>  * Enable DEVX/mlx5_ib to register for ANY event instead of the option to
>    get some hard-coded ones.
>  * Enable DEVX/mlx5_ib to get the device raw data for CQ completion events.
>  * Enhance mlx5_core_create/destroy CQ to enable DEVX using them so that CQ
>    events will be reported as well.
> 
> In mlx5_ib layer the below changes were done:
>  * A new DEVX API was introduced to allocate an event channel by using
>    the uverbs FD object type.
>  * Implement the FD channel operations to enable read/poo/close over it.
>  * A new DEVX API was introduced to subscribe for specific events over an
>    event channel.
>  * Manage an internal data structure  over XA(s) to subscribe/dispatch events
>    over the different event channels.
>  * Use from DEVX the mlx5_core APIs to create/destroy a CQ to be able to
>    get its relevant events.
> 
> Yishai
> 
> Yishai Hadas (13):
>   net/mlx5: Fix mlx5_core_destroy_cq() error flow
>   net/mlx5: Use event mask based on device capabilities
>   net/mlx5: Expose the API to register for ANY event
>   net/mlx5: mlx5_core_create_cq() enhancements
>   net/mlx5: Report a CQ error event only when a handler was set
>   net/mlx5: Report EQE data upon CQ completion
>   net/mlx5: Expose device definitions for object events
>   IB/mlx5: Introduce MLX5_IB_OBJECT_DEVX_ASYNC_EVENT_FD
>   IB/mlx5: Register DEVX with mlx5_core to get async events
>   IB/mlx5: Enable subscription for device events over DEVX
>   IB/mlx5: Implement DEVX dispatching event
>   IB/mlx5: Add DEVX support for CQ events
>   IB/mlx5: DEVX cleanup mdev

This looks OK now, can you please apply the net patches to the shared
branch

Thanks,
Jason