RDMA/umem: Get rid of per_mm->notifier_count
This is intrinsically racy and the scheme is simply unnecessary. New MR
registration can wait for any on going invalidation to fully complete.
CPU0 CPU1
if (atomic_read())
if (atomic_dec_and_test() &&
!list_empty())
{ /* not taken */ }
list_add()
Putting the new UMEM into some kind of purgatory until another invalidate
rolls through..
Instead hold the read side of the umem_rwsem across the pair'd start/end
and get rid of the racy 'deferred add' approach.
Since all umem's in the rbt are always ready to go, also get rid of the
mn_counters_active stuff.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2 files changed