Re: [PATCH v3 -next 10/15] fs: drop_caches: move sysctl to fs/drop_caches.c

From: Jan Kara
Date: Mon Oct 14 2024 - 08:16:08 EST


On Thu 10-10-24 23:22:10, Kaixiong Yu wrote:
> The sysctl_drop_caches to fs/drop_caches.c, move it to
> fs/drop_caches.c from /kernel/sysctl.c. And remove the
> useless extern variable declaration from include/linux/mm.h
>
> Signed-off-by: Kaixiong Yu <yukaixiong@xxxxxxxxxx>
> Reviewed-by: Kees Cook <kees@xxxxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza

> ---
> v3:
> - change the title
> ---
> fs/drop_caches.c | 23 +++++++++++++++++++++--
> include/linux/mm.h | 6 ------
> kernel/sysctl.c | 9 ---------
> 3 files changed, 21 insertions(+), 17 deletions(-)
>
> diff --git a/fs/drop_caches.c b/fs/drop_caches.c
> index d45ef541d848..f2551ace800f 100644
> --- a/fs/drop_caches.c
> +++ b/fs/drop_caches.c
> @@ -14,7 +14,7 @@
> #include "internal.h"
>
> /* A global variable is a bit ugly, but it keeps the code simple */
> -int sysctl_drop_caches;
> +static int sysctl_drop_caches;
>
> static void drop_pagecache_sb(struct super_block *sb, void *unused)
> {
> @@ -48,7 +48,7 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
> iput(toput_inode);
> }
>
> -int drop_caches_sysctl_handler(const struct ctl_table *table, int write,
> +static int drop_caches_sysctl_handler(const struct ctl_table *table, int write,
> void *buffer, size_t *length, loff_t *ppos)
> {
> int ret;
> @@ -77,3 +77,22 @@ int drop_caches_sysctl_handler(const struct ctl_table *table, int write,
> }
> return 0;
> }
> +
> +static struct ctl_table drop_caches_table[] = {
> + {
> + .procname = "drop_caches",
> + .data = &sysctl_drop_caches,
> + .maxlen = sizeof(int),
> + .mode = 0200,
> + .proc_handler = drop_caches_sysctl_handler,
> + .extra1 = SYSCTL_ONE,
> + .extra2 = SYSCTL_FOUR,
> + },
> +};
> +
> +static int __init init_vm_drop_caches_sysctls(void)
> +{
> + register_sysctl_init("vm", drop_caches_table);
> + return 0;
> +}
> +fs_initcall(init_vm_drop_caches_sysctls);
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index c7f73bf32024..ed2e7425c838 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -3791,12 +3791,6 @@ static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
>
> extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
>
> -#ifdef CONFIG_SYSCTL
> -extern int sysctl_drop_caches;
> -int drop_caches_sysctl_handler(const struct ctl_table *, int, void *, size_t *,
> - loff_t *);
> -#endif
> -
> void drop_slab(void);
>
> #ifndef CONFIG_MMU
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 373e018b950c..d638a1bac9af 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -2024,15 +2024,6 @@ static struct ctl_table kern_table[] = {
> };
>
> static struct ctl_table vm_table[] = {
> - {
> - .procname = "drop_caches",
> - .data = &sysctl_drop_caches,
> - .maxlen = sizeof(int),
> - .mode = 0200,
> - .proc_handler = drop_caches_sysctl_handler,
> - .extra1 = SYSCTL_ONE,
> - .extra2 = SYSCTL_FOUR,
> - },
> {
> .procname = "vfs_cache_pressure",
> .data = &sysctl_vfs_cache_pressure,
> --
> 2.34.1
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR