On Wed, Mar 18, 2020 at 09:54:59AM -0300, Jason Gunthorpe wrote: > On Wed, Mar 18, 2020 at 02:43:25PM +0200, Leon Romanovsky wrote: > > From: Leon Romanovsky <leonro@xxxxxxxxxxxx> > > > > From Yishai, > > > > This series exposes API to enable a dynamic allocation and management of a > > UAR which now becomes to be a regular uobject. > > > > Moving to that mode enables allocating a UAR only upon demand and drop the > > redundant static allocation of UARs upon context creation. > > > > In addition, it allows master and secondary processes that own the same command > > FD to allocate and manage UARs according to their needs, this can’t be achieved > > today. > > > > As part of this option, QP & CQ creation flows were adapted to support this > > dynamic UAR mode once asked by user space. > > > > Once this mode is asked by mlx5 user space driver on a given context, it will > > be mutual exclusive, means both the static and legacy dynamic modes for using > > UARs will be blocked. > > > > The legacy modes are supported for backward compatible reasons, looking > > forward we expect this new mode to be the default. > > We are starting to accumulate a lot of code that is now old-rdma-core > only. Agree > > I have been wondering if we should add something like > > #if CONFIG_INFINIBAND_MIN_RDMA_CORE_VERSION < 21 > #endif >From one side it will definitely help to see old code, but from another it will create many ifdef inside of the code with a very little chance of testing. Also we will continue to have the same problem to decide when we can delete this code. > > So we can keep track of what is actually a used code flow and what is > now hard to test legacy code. > > eg this config would also disable the write interface(), turn off > compat write interfaces as they are switched to use ioctl, etc, etc. What about if we introduce one ifdef, let's say CONFIG_INFINIBAND_LEGACY and put everything that will be declared as legacy to that bucket? And once every 5 (???) years delete everything from that bucket. > > Jason
