On Fri, Oct 04, 2019 at 12:06:01AM +0200, Jan Kara wrote:
> jbd2__journal_restart() has quite some code that is common with
> jbd2_journal_stop(). Factor this functionality into stop_this_handle()
> helper and use it from both functions. Note that this also drops
> t_handle_lock protection from jbd2__journal_restart() as
> jbd2_journal_stop() does the same thing without it.
>
> Signed-off-by: Jan Kara <jack@xxxxxxx>
> ---
> fs/jbd2/transaction.c | 94 +++++++++++++++++++++++----------------------------
> 1 file changed, 42 insertions(+), 52 deletions(-)
>
> diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
> index d648cec3f90f..d4ee02e5161b 100644
> --- a/fs/jbd2/transaction.c
> +++ b/fs/jbd2/transaction.c
> @@ -677,52 +704,30 @@ int jbd2__journal_restart(handle_t *handle, int nblocks, gfp_t gfp_mask)
> - read_lock(&journal->j_state_lock);
> - spin_lock(&transaction->t_handle_lock);
> - atomic_sub(handle->h_buffer_credits,
> - &transaction->t_outstanding_credits);
> - if (handle->h_rsv_handle) {
> - sub_reserved_credits(journal,
> - handle->h_rsv_handle->h_buffer_credits);
> - }
> - if (atomic_dec_and_test(&transaction->t_updates))
> - wake_up(&journal->j_wait_updates);
> - tid = transaction->t_tid;
> - spin_unlock(&transaction->t_handle_lock);
> + jbd_debug(2, "restarting handle %p\n", handle);
> + stop_this_handle(handle);
> handle->h_transaction = NULL;
> - current->journal_info = NULL;
>
> - jbd_debug(2, "restarting handle %p\n", handle);
> + read_lock(&journal->j_state_lock);
> need_to_start = !tid_geq(journal->j_commit_request, tid);
> read_unlock(&journal->j_state_lock);
What is j_state_lock protecting at this point? There's only a 32-bit
read of j_commit_request at this point.
- Ted
