2013-04-22 01:11:49

by majianpeng

Subject: [PATCH V1] fs/buffer.c: Remove unnecessary init operation after, allocating buffer_head.

Because alloc 'struct buffer_head' using kmem_cache_zalloc,so it doesn't
need to call 'init_buffer(bh, NULL, NULL)' and other set-zero-operation.

Signed-off-by: Jianpeng Ma <[email protected]>
---
fs/buffer.c | 2 --
fs/jbd/journal.c | 2 --
fs/jbd2/journal.c | 2 --
3 files changed, 6 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index b4dcb34..52b7739 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -865,8 +865,6 @@ try_again:

/* Link the buffer to its page */
set_bh_page(bh, page, offset);
-
- init_buffer(bh, NULL, NULL);
}
return head;
/*
diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c
index 81cc7ea..865c430 100644
--- a/fs/jbd/journal.c
+++ b/fs/jbd/journal.c
@@ -310,8 +310,6 @@ int journal_write_metadata_buffer(transaction_t *transaction,

new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
/* keep subsequent assertions sane */
- new_bh->b_state = 0;
- init_buffer(new_bh, NULL, NULL);
atomic_set(&new_bh->b_count, 1);
new_jh = journal_add_journal_head(new_bh); /* This sleeps */

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index ed10991..8b220f1 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -367,8 +367,6 @@ retry_alloc:
}

/* keep subsequent assertions sane */
- new_bh->b_state = 0;
- init_buffer(new_bh, NULL, NULL);
atomic_set(&new_bh->b_count, 1);
new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */

--
1.8.2.rc2.4.g7799588

2013-04-23 08:54:57

by Jan Kara

Subject: Re: [PATCH V1] fs/buffer.c: Remove unnecessary init operation after, allocating buffer_head.

On Mon 22-04-13 09:11:33, majianpeng wrote:
> Because alloc 'struct buffer_head' using kmem_cache_zalloc,so it doesn't
> need to call 'init_buffer(bh, NULL, NULL)' and other set-zero-operation.
>
> Signed-off-by: Jianpeng Ma <[email protected]>
Looks good. If noone objects, I'll merge the patch through my tree.

Honza
> ---
> fs/buffer.c | 2 --
> fs/jbd/journal.c | 2 --
> fs/jbd2/journal.c | 2 --
> 3 files changed, 6 deletions(-)
>
> diff --git a/fs/buffer.c b/fs/buffer.c
> index b4dcb34..52b7739 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -865,8 +865,6 @@ try_again:
>
> /* Link the buffer to its page */
> set_bh_page(bh, page, offset);
> -
> - init_buffer(bh, NULL, NULL);
> }
> return head;
> /*
> diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c
> index 81cc7ea..865c430 100644
> --- a/fs/jbd/journal.c
> +++ b/fs/jbd/journal.c
> @@ -310,8 +310,6 @@ int journal_write_metadata_buffer(transaction_t *transaction,
>
> new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
> /* keep subsequent assertions sane */
> - new_bh->b_state = 0;
> - init_buffer(new_bh, NULL, NULL);
> atomic_set(&new_bh->b_count, 1);
> new_jh = journal_add_journal_head(new_bh); /* This sleeps */
>
> diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
> index ed10991..8b220f1 100644
> --- a/fs/jbd2/journal.c
> +++ b/fs/jbd2/journal.c
> @@ -367,8 +367,6 @@ retry_alloc:
> }
>
> /* keep subsequent assertions sane */
> - new_bh->b_state = 0;
> - init_buffer(new_bh, NULL, NULL);
> atomic_set(&new_bh->b_count, 1);
> new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */
>
> --
> 1.8.2.rc2.4.g7799588
>
--
Jan Kara <[email protected]>
SUSE Labs, CR

2013-04-23 08:59:52

by Jan Kara

Subject: Re: [PATCH V1] fs/buffer.c: Remove unnecessary init operation after, allocating buffer_head.

On Mon 22-04-13 09:11:33, majianpeng wrote:
> Because alloc 'struct buffer_head' using kmem_cache_zalloc,so it doesn't
> need to call 'init_buffer(bh, NULL, NULL)' and other set-zero-operation.
>
> Signed-off-by: Jianpeng Ma <[email protected]>
I've just noticed the whitespace is still mangled. Gmail is known for
destroying whitespace so please send the patch as an attachment. Thanks.

Honza

> ---
> fs/buffer.c | 2 --
> fs/jbd/journal.c | 2 --
> fs/jbd2/journal.c | 2 --
> 3 files changed, 6 deletions(-)
>
> diff --git a/fs/buffer.c b/fs/buffer.c
> index b4dcb34..52b7739 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -865,8 +865,6 @@ try_again:
>
> /* Link the buffer to its page */
> set_bh_page(bh, page, offset);
> -
> - init_buffer(bh, NULL, NULL);
> }
> return head;
> /*
> diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c
> index 81cc7ea..865c430 100644
> --- a/fs/jbd/journal.c
> +++ b/fs/jbd/journal.c
> @@ -310,8 +310,6 @@ int journal_write_metadata_buffer(transaction_t *transaction,
>
> new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
> /* keep subsequent assertions sane */
> - new_bh->b_state = 0;
> - init_buffer(new_bh, NULL, NULL);
> atomic_set(&new_bh->b_count, 1);
> new_jh = journal_add_journal_head(new_bh); /* This sleeps */
>
> diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
> index ed10991..8b220f1 100644
> --- a/fs/jbd2/journal.c
> +++ b/fs/jbd2/journal.c
> @@ -367,8 +367,6 @@ retry_alloc:
> }
>
> /* keep subsequent assertions sane */
> - new_bh->b_state = 0;
> - init_buffer(new_bh, NULL, NULL);
> atomic_set(&new_bh->b_count, 1);
> new_jh = jbd2_journal_add_journal_head(new_bh); /* This sleeps */
>
> --
> 1.8.2.rc2.4.g7799588
>
--
Jan Kara <[email protected]>
SUSE Labs, CR