On Fri, Jul 08, 2022 at 11:55:53AM +1000, Dave Chinner wrote:
> lockdep_assert_held(&log->l_icloglock);
> @@ -544,7 +543,7 @@ xlog_state_release_iclog(
> if ((iclog->ic_state == XLOG_STATE_WANT_SYNC ||
> (iclog->ic_flags & XLOG_ICL_NEED_FUA)) &&
> !iclog->ic_header.h_tail_lsn) {
> - tail_lsn = xlog_assign_tail_lsn(log->l_mp);
> + xfs_lsn_t tail_lsn = atomic64_read(&log->l_tail_lsn);
> iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn);
Nit: I'd just do this as:
iclog->ic_header.h_tail_lsn =
cpu_to_be64(atomic64_read(&log->l_tail_lsn));
> +/*
> + * Callers should pass the the original tail lsn so that we can detect if the
> + * tail has moved as a result of the operation that was performed. If the caller
> + * needs to force a tail LSN update, it should pass NULLCOMMITLSN to bypass the
> + * "did the tail LSN change?" checks.
> + */
Should we also document the old_lsn == 0 case here?
