[PATCH] mm: Remove sysctl_extfrag_handler

[PATCH] mm: Remove sysctl_extfrag_handler

[Matthew Wilcox]

The sysctl_extfrag_handler function neglects to propagate the return
value from proc_dointvec_minmax() to its caller.  It's a wrapper that
doesn't need to exist, so just use proc_dointvec_minmax directly.

Reported-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
---
 include/linux/compaction.h | 2 --
 kernel/sysctl.c            | 2 +-
 mm/compaction.c            | 8 --------
 3 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index 68250a57aace..70d0256edd31 100644
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -88,8 +88,6 @@ extern int sysctl_compact_memory;
 extern int sysctl_compaction_handler(struct ctl_table *table, int write,
 			void __user *buffer, size_t *length, loff_t *ppos);
 extern int sysctl_extfrag_threshold;
-extern int sysctl_extfrag_handler(struct ctl_table *table, int write,
-			void __user *buffer, size_t *length, loff_t *ppos);
 extern int sysctl_compact_unevictable_allowed;
 
 extern int fragmentation_index(struct zone *zone, unsigned int order);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 5fc724e4e454..e9c69247fc29 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1439,7 +1439,7 @@ static struct ctl_table vm_table[] = {
 		.data		= &sysctl_extfrag_threshold,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= sysctl_extfrag_handler,
+		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= &min_extfrag_threshold,
 		.extra2		= &max_extfrag_threshold,
 	},
diff --git a/mm/compaction.c b/mm/compaction.c
index 7c607479de4a..80b941d9b6e7 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1876,14 +1876,6 @@ int sysctl_compaction_handler(struct ctl_table *table, int write,
 	return 0;
 }
 
-int sysctl_extfrag_handler(struct ctl_table *table, int write,
-			void __user *buffer, size_t *length, loff_t *ppos)
-{
-	proc_dointvec_minmax(table, write, buffer, length, ppos);
-
-	return 0;
-}
-
 #if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
 static ssize_t sysfs_compact_node(struct device *dev,
 			struct device_attribute *attr,
-- 
2.20.1

Re: [PATCH] mm: Remove sysctl_extfrag_handler

[Randy Dunlap]

On 1/3/19 7:25 PM, Matthew Wilcox wrote:
> The sysctl_extfrag_handler function neglects to propagate the return
> value from proc_dointvec_minmax() to its caller.  It's a wrapper that
> doesn't need to exist, so just use proc_dointvec_minmax directly.
> 
> Reported-by: Aditya Pakki <pakki001@umn.edu>
> Signed-off-by: Matthew Wilcox <willy@infradead.org>
> Acked-by: Mel Gorman <mgorman@techsingularity.net>

Acked-by: Randy Dunlap <rdunlap@infradead.org>

Thanks.

> ---
>  include/linux/compaction.h | 2 --
>  kernel/sysctl.c            | 2 +-
>  mm/compaction.c            | 8 --------
>  3 files changed, 1 insertion(+), 11 deletions(-)
> 
> diff --git a/include/linux/compaction.h b/include/linux/compaction.h
> index 68250a57aace..70d0256edd31 100644
> --- a/include/linux/compaction.h
> +++ b/include/linux/compaction.h
> @@ -88,8 +88,6 @@ extern int sysctl_compact_memory;
>  extern int sysctl_compaction_handler(struct ctl_table *table, int write,
>  			void __user *buffer, size_t *length, loff_t *ppos);
>  extern int sysctl_extfrag_threshold;
> -extern int sysctl_extfrag_handler(struct ctl_table *table, int write,
> -			void __user *buffer, size_t *length, loff_t *ppos);
>  extern int sysctl_compact_unevictable_allowed;
>  
>  extern int fragmentation_index(struct zone *zone, unsigned int order);
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 5fc724e4e454..e9c69247fc29 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -1439,7 +1439,7 @@ static struct ctl_table vm_table[] = {
>  		.data		= &sysctl_extfrag_threshold,
>  		.maxlen		= sizeof(int),
>  		.mode		= 0644,
> -		.proc_handler	= sysctl_extfrag_handler,
> +		.proc_handler	= proc_dointvec_minmax,
>  		.extra1		= &min_extfrag_threshold,
>  		.extra2		= &max_extfrag_threshold,
>  	},
> diff --git a/mm/compaction.c b/mm/compaction.c
> index 7c607479de4a..80b941d9b6e7 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -1876,14 +1876,6 @@ int sysctl_compaction_handler(struct ctl_table *table, int write,
>  	return 0;
>  }
>  
> -int sysctl_extfrag_handler(struct ctl_table *table, int write,
> -			void __user *buffer, size_t *length, loff_t *ppos)
> -{
> -	proc_dointvec_minmax(table, write, buffer, length, ppos);
> -
> -	return 0;
> -}
> -
>  #if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
>  static ssize_t sysfs_compact_node(struct device *dev,
>  			struct device_attribute *attr,
> 


-- 
~Randy