Re: [PATCH v3 5/8] jbd2: remove unneeded done_copy_out variable in jbd2_journal_write_metadata_buffer

From: Zhang Yi
Date: Wed Jul 31 2024 - 07:57:58 EST


On 2024/7/31 17:29, Kemeng Shi wrote:
> It's more intuitive to use jh_in->b_frozen_data directly instead of
> done_copy_out variable. Simply remove unneeded done_copy_out variable
> and use b_frozen_data instead.
>
> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>

Looks good to me.

Reviewed-by: Zhang Yi <yi.zhang@xxxxxxxxxx>

> ---
> fs/jbd2/journal.c | 21 ++++++++-------------
> 1 file changed, 8 insertions(+), 13 deletions(-)
>
> diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
> index 9c1ffb0dc740..f17d05bc61df 100644
> --- a/fs/jbd2/journal.c
> +++ b/fs/jbd2/journal.c
> @@ -318,7 +318,6 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
> struct buffer_head **bh_out,
> sector_t blocknr)
> {
> - int done_copy_out = 0;
> int do_escape = 0;
> char *mapped_data;
> struct buffer_head *new_bh;
> @@ -349,7 +348,6 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
> * we use that version of the data for the commit.
> */
> if (jh_in->b_frozen_data) {
> - done_copy_out = 1;
> new_folio = virt_to_folio(jh_in->b_frozen_data);
> new_offset = offset_in_folio(new_folio, jh_in->b_frozen_data);
> mapped_data = jh_in->b_frozen_data;
> @@ -357,17 +355,15 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
> new_folio = bh_in->b_folio;
> new_offset = offset_in_folio(new_folio, bh_in->b_data);
> mapped_data = kmap_local_folio(new_folio, new_offset);
> - }
> -
> - /*
> - * Fire data frozen trigger if data already wasn't frozen. Do this
> - * before checking for escaping, as the trigger may modify the magic
> - * offset. If a copy-out happens afterwards, it will have the correct
> - * data in the buffer.
> - */
> - if (!done_copy_out)
> + /*
> + * Fire data frozen trigger if data already wasn't frozen. Do
> + * this before checking for escaping, as the trigger may modify
> + * the magic offset. If a copy-out happens afterwards, it will
> + * have the correct data in the buffer.
> + */
> jbd2_buffer_frozen_trigger(jh_in, mapped_data,
> jh_in->b_triggers);
> + }
>
> /*
> * Check for escaping
> @@ -380,7 +376,7 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
> /*
> * Do we need to do a data copy?
> */
> - if (do_escape && !done_copy_out) {
> + if (do_escape && !jh_in->b_frozen_data) {
> char *tmp;
>
> spin_unlock(&jh_in->b_state_lock);
> @@ -408,7 +404,6 @@ int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
> copy_done:
> new_folio = virt_to_folio(jh_in->b_frozen_data);
> new_offset = offset_in_folio(new_folio, jh_in->b_frozen_data);
> - done_copy_out = 1;
> }
>
> /*
>