• Eric Dumazet's avatar
    net: fix lock_sock_bh/unlock_sock_bh · 8a74ad60
    Eric Dumazet authored
    This new sock lock primitive was introduced to speedup some user context
    socket manipulation. But it is unsafe to protect two threads, one using
    regular lock_sock/release_sock, one using lock_sock_bh/unlock_sock_bh
    This patch changes lock_sock_bh to be careful against 'owned' state.
    If owned is found to be set, we must take the slow path.
    lock_sock_bh() now returns a boolean to say if the slow path was taken,
    and this boolean is used at unlock_sock_bh time to call the appropriate
    unlock function.
    After this change, BH are either disabled or enabled during the
    lock_sock_bh/unlock_sock_bh protected section. This might be misleading,
    so we rename these functions to lock_sock_fast()/unlock_sock_fast().
    Reported-by: default avatarAnton Blanchard <anton@samba.org>
    Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
    Tested-by: default avatarAnton Blanchard <anton@samba.org>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
sock.c 62.9 KB