2018-09-13 03:13:56

by zhong jiang

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Subject: [PATCHv3 0/2] change some function to be void function


zhong jiang (2):
btrfs: change unpin_extent_cache to be void function
btrfs: change remove_extent_mapping to be void function

fs/btrfs/extent_map.c | 10 ++--------
fs/btrfs/extent_map.h | 4 ++--
2 files changed, 4 insertions(+), 10 deletions(-)

--
1.7.12.4



2018-09-13 03:14:07

by zhong jiang

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Subject: [PATCHv3 1/2] btrfs: change unpin_extent_cache to be void function

unpin_extent_cache use the the variable "ret" for return value,
but it is not modified after initialzation. Further, I find that
any of the callers do not handle the return value, so it is safe
to drop the unneeded "ret" and make it to be void function.

Signed-off-by: zhong jiang <[email protected]>
---
fs/btrfs/extent_map.c | 5 +----
fs/btrfs/extent_map.h | 2 +-
2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 819420e..c4e2347 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -276,10 +276,9 @@ static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
* to the generation that actually added the file item to the inode so we know
* we need to sync this extent when we call fsync().
*/
-int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
+void unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
u64 gen)
{
- int ret = 0;
struct extent_map *em;
bool prealloc = false;

@@ -311,8 +310,6 @@ int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
free_extent_map(em);
out:
write_unlock(&tree->lock);
- return ret;
-
}

void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em)
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 6afe786..df4e1a5 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -88,7 +88,7 @@ void replace_extent_mapping(struct extent_map_tree *tree,
void free_extent_map(struct extent_map *em);
int __init extent_map_init(void);
void __cold extent_map_exit(void);
-int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
+void unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em);
struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 len);
--
1.7.12.4


2018-09-13 03:16:25

by zhong jiang

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Subject: [PATCHv3 2/2] btrfs: change remove_extent_mapping to be void function

remove_extent_mapping use the variable "ret" for return value,
but it is not modified after initialzation. Further, I find that
any of the callers do not handle the return value, so it is safe
to drop the unneeded "ret" and make it to be void function.

Signed-off-by: zhong jiang <[email protected]>
---
fs/btrfs/extent_map.c | 5 +----
fs/btrfs/extent_map.h | 2 +-
2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index c4e2347..81b6a08 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -428,16 +428,13 @@ struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
* Removes @em from @tree. No reference counts are dropped, and no checks
* are done to see if the range is in use
*/
-int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
+void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
{
- int ret = 0;
-
WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
rb_erase_cached(&em->rb_node, &tree->map);
if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags))
list_del_init(&em->list);
RB_CLEAR_NODE(&em->rb_node);
- return ret;
}

void replace_extent_mapping(struct extent_map_tree *tree,
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index df4e1a5..8798745 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -78,7 +78,7 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 len);
int add_extent_mapping(struct extent_map_tree *tree,
struct extent_map *em, int modified);
-int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
+void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
void replace_extent_mapping(struct extent_map_tree *tree,
struct extent_map *cur,
struct extent_map *new,
--
1.7.12.4


2018-09-13 05:54:37

by Nikolay Borisov

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Subject: Re: [PATCHv3 2/2] btrfs: change remove_extent_mapping to be void function



On 13.09.2018 06:01, zhong jiang wrote:
> remove_extent_mapping use the variable "ret" for return value,
> but it is not modified after initialzation. Further, I find that
> any of the callers do not handle the return value, so it is safe
> to drop the unneeded "ret" and make it to be void function.
>
> Signed-off-by: zhong jiang <[email protected]>

Reviewed-by: Nikolay Borisov <[email protected]

> ---
> fs/btrfs/extent_map.c | 5 +----
> fs/btrfs/extent_map.h | 2 +-
> 2 files changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
> index c4e2347..81b6a08 100644
> --- a/fs/btrfs/extent_map.c
> +++ b/fs/btrfs/extent_map.c
> @@ -428,16 +428,13 @@ struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
> * Removes @em from @tree. No reference counts are dropped, and no checks
> * are done to see if the range is in use
> */
> -int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
> +void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
> {
> - int ret = 0;
> -
> WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
> rb_erase_cached(&em->rb_node, &tree->map);
> if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags))
> list_del_init(&em->list);
> RB_CLEAR_NODE(&em->rb_node);
> - return ret;
> }
>
> void replace_extent_mapping(struct extent_map_tree *tree,
> diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
> index df4e1a5..8798745 100644
> --- a/fs/btrfs/extent_map.h
> +++ b/fs/btrfs/extent_map.h
> @@ -78,7 +78,7 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
> u64 start, u64 len);
> int add_extent_mapping(struct extent_map_tree *tree,
> struct extent_map *em, int modified);
> -int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
> +void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
> void replace_extent_mapping(struct extent_map_tree *tree,
> struct extent_map *cur,
> struct extent_map *new,
>

2018-09-14 14:17:57

by David Sterba

[permalink] [raw]
Subject: Re: [PATCHv3 2/2] btrfs: change remove_extent_mapping to be void function

On Thu, Sep 13, 2018 at 11:01:15AM +0800, zhong jiang wrote:
> remove_extent_mapping use the variable "ret" for return value,
> but it is not modified after initialzation. Further, I find that
> any of the callers do not handle the return value, so it is safe
> to drop the unneeded "ret" and make it to be void function.
>
> Signed-off-by: zhong jiang <[email protected]>

Reviewed-by: David Sterba <[email protected]>