account_pipe_buffers
user_bufs = account_pipe_buffers(pipe->user, pipe->nr_accounted, nr_slots);
(void) account_pipe_buffers(pipe->user, nr_slots, pipe->nr_accounted);
user_bufs = account_pipe_buffers(user, 0, pipe_bufs);
user_bufs = account_pipe_buffers(user, pipe_bufs, PIPE_MIN_DEF_BUFFERS);
(void) account_pipe_buffers(user, pipe_bufs, 0);
(void) account_pipe_buffers(pipe->user, pipe->nr_accounted, 0);
unsigned long account_pipe_buffers(struct user_struct *user,
user_bufs = account_pipe_buffers(pipe->user, pipe->nr_accounted, nr_pages);
(void) account_pipe_buffers(pipe->user, nr_pages, pipe->nr_accounted);