• David Howells's avatar
    afs: Split the usage count on struct afs_server · 977e5f8e
    David Howells authored
    Split the usage count on the afs_server struct to have an active count that
    registers who's actually using it separately from the reference count on
    the object.
    
    This allows a future patch to dispatch polling probes without advancing the
    "unuse" time into the future each time we emit a probe, which would
    otherwise prevent unused server records from expiring.
    
    Included in this:
    
     (1) The latter part of afs_destroy_server() in which the RCU destruction
         of afs_server objects is invoked and the outstanding server count is
         decremented is split out into __afs_put_server().
    
     (2) afs_put_server() now calls __afs_put_server() rather then setting the
         management timer.
    
     (3) The calls begun by afs_fs_give_up_all_callbacks() and
         afs_fs_get_capabilities() can now take a ref on the server record, so
         afs_destroy_server() can just drop its ref and needn't wait for the
         completion of these calls.  They'll put the ref when they're done.
    
     (4) Because of (3), afs_fs_probe_done() no longer needs to wake up
         afs_destroy_server() with server->probe_outstanding.
    
     (5) afs_gc_servers can be simplified.  It only needs to check if
         server->active is 0 rather than playing games with the refcount.
    
     (6) afs_manage_servers() can propose a server for gc if usage == 0 rather
         than if ref == 1.  The gc is effected by (5).
    Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
    977e5f8e
cmservice.c 17.3 KB