| From: zhanglianjie <zhanglianjie@uniontech.com> |
| Subject: mm: move page-writeback sysctls to their own file |
| |
| kernel/sysctl.c is a kitchen sink where everyone leaves their dirty |
| dishes, this makes it very difficult to maintain. |
| |
| To help with this maintenance let's start by moving sysctls to places |
| where they actually belong. The proc sysctl maintainers do not want to |
| know what sysctl knobs you wish to add for your own piece of code, we just |
| care about the core logic. |
| |
| So move the page-writeback sysctls to its own file. |
| |
| [akpm@linux-foundation.org: coding-style cleanups] |
| akpm@linux-foundation.org: fix CONFIG_SYSCTL=n warnings] |
| Link: https://lkml.kernel.org/r/20220129012955.26594-1-zhanglianjie@uniontech.com |
| Signed-off-by: zhanglianjie <zhanglianjie@uniontech.com> |
| Cc: Kees Cook <keescook@chromium.org> |
| Cc: Iurii Zaikin <yzaikin@google.com> |
| Cc: Luis Chamberlain <mcgrof@kernel.org> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| --- |
| |
| include/linux/writeback.h | 15 ----- |
| kernel/sysctl.c | 69 ------------------------ |
| mm/page-writeback.c | 103 ++++++++++++++++++++++++++++++++---- |
| 3 files changed, 93 insertions(+), 94 deletions(-) |
| |
| --- a/include/linux/writeback.h~mm-move-page-writeback-sysctls-to-is-own-file |
| +++ a/include/linux/writeback.h |
| @@ -345,28 +345,13 @@ void wb_domain_exit(struct wb_domain *do |
| extern struct wb_domain global_wb_domain; |
| |
| /* These are exported to sysctl. */ |
| -extern int dirty_background_ratio; |
| -extern unsigned long dirty_background_bytes; |
| -extern int vm_dirty_ratio; |
| -extern unsigned long vm_dirty_bytes; |
| extern unsigned int dirty_writeback_interval; |
| extern unsigned int dirty_expire_interval; |
| extern unsigned int dirtytime_expire_interval; |
| -extern int vm_highmem_is_dirtyable; |
| extern int laptop_mode; |
| |
| -int dirty_background_ratio_handler(struct ctl_table *table, int write, |
| - void *buffer, size_t *lenp, loff_t *ppos); |
| -int dirty_background_bytes_handler(struct ctl_table *table, int write, |
| - void *buffer, size_t *lenp, loff_t *ppos); |
| -int dirty_ratio_handler(struct ctl_table *table, int write, |
| - void *buffer, size_t *lenp, loff_t *ppos); |
| -int dirty_bytes_handler(struct ctl_table *table, int write, |
| - void *buffer, size_t *lenp, loff_t *ppos); |
| int dirtytime_interval_handler(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos); |
| -int dirty_writeback_centisecs_handler(struct ctl_table *table, int write, |
| - void *buffer, size_t *lenp, loff_t *ppos); |
| |
| void global_dirty_limits(unsigned long *pbackground, unsigned long *pdirty); |
| unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh); |
| --- a/kernel/sysctl.c~mm-move-page-writeback-sysctls-to-is-own-file |
| +++ a/kernel/sysctl.c |
| @@ -100,8 +100,6 @@ |
| static const int six_hundred_forty_kb = 640 * 1024; |
| #endif |
| |
| -/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */ |
| -static const unsigned long dirty_bytes_min = 2 * PAGE_SIZE; |
| |
| static const int ngroups_max = NGROUPS_MAX; |
| static const int cap_last_cap = CAP_LAST_CAP; |
| @@ -2377,55 +2375,6 @@ static struct ctl_table vm_table[] = { |
| .extra1 = SYSCTL_ZERO, |
| }, |
| { |
| - .procname = "dirty_background_ratio", |
| - .data = &dirty_background_ratio, |
| - .maxlen = sizeof(dirty_background_ratio), |
| - .mode = 0644, |
| - .proc_handler = dirty_background_ratio_handler, |
| - .extra1 = SYSCTL_ZERO, |
| - .extra2 = SYSCTL_ONE_HUNDRED, |
| - }, |
| - { |
| - .procname = "dirty_background_bytes", |
| - .data = &dirty_background_bytes, |
| - .maxlen = sizeof(dirty_background_bytes), |
| - .mode = 0644, |
| - .proc_handler = dirty_background_bytes_handler, |
| - .extra1 = SYSCTL_LONG_ONE, |
| - }, |
| - { |
| - .procname = "dirty_ratio", |
| - .data = &vm_dirty_ratio, |
| - .maxlen = sizeof(vm_dirty_ratio), |
| - .mode = 0644, |
| - .proc_handler = dirty_ratio_handler, |
| - .extra1 = SYSCTL_ZERO, |
| - .extra2 = SYSCTL_ONE_HUNDRED, |
| - }, |
| - { |
| - .procname = "dirty_bytes", |
| - .data = &vm_dirty_bytes, |
| - .maxlen = sizeof(vm_dirty_bytes), |
| - .mode = 0644, |
| - .proc_handler = dirty_bytes_handler, |
| - .extra1 = (void *)&dirty_bytes_min, |
| - }, |
| - { |
| - .procname = "dirty_writeback_centisecs", |
| - .data = &dirty_writeback_interval, |
| - .maxlen = sizeof(dirty_writeback_interval), |
| - .mode = 0644, |
| - .proc_handler = dirty_writeback_centisecs_handler, |
| - }, |
| - { |
| - .procname = "dirty_expire_centisecs", |
| - .data = &dirty_expire_interval, |
| - .maxlen = sizeof(dirty_expire_interval), |
| - .mode = 0644, |
| - .proc_handler = proc_dointvec_minmax, |
| - .extra1 = SYSCTL_ZERO, |
| - }, |
| - { |
| .procname = "dirtytime_expire_seconds", |
| .data = &dirtytime_expire_interval, |
| .maxlen = sizeof(dirtytime_expire_interval), |
| @@ -2597,13 +2546,6 @@ static struct ctl_table vm_table[] = { |
| }, |
| #endif |
| { |
| - .procname = "laptop_mode", |
| - .data = &laptop_mode, |
| - .maxlen = sizeof(laptop_mode), |
| - .mode = 0644, |
| - .proc_handler = proc_dointvec_jiffies, |
| - }, |
| - { |
| .procname = "vfs_cache_pressure", |
| .data = &sysctl_vfs_cache_pressure, |
| .maxlen = sizeof(sysctl_vfs_cache_pressure), |
| @@ -2700,17 +2642,6 @@ static struct ctl_table vm_table[] = { |
| .extra1 = SYSCTL_ZERO, |
| }, |
| #endif |
| -#ifdef CONFIG_HIGHMEM |
| - { |
| - .procname = "highmem_is_dirtyable", |
| - .data = &vm_highmem_is_dirtyable, |
| - .maxlen = sizeof(vm_highmem_is_dirtyable), |
| - .mode = 0644, |
| - .proc_handler = proc_dointvec_minmax, |
| - .extra1 = SYSCTL_ZERO, |
| - .extra2 = SYSCTL_ONE, |
| - }, |
| -#endif |
| #ifdef CONFIG_MEMORY_FAILURE |
| { |
| .procname = "memory_failure_early_kill", |
| --- a/mm/page-writeback.c~mm-move-page-writeback-sysctls-to-is-own-file |
| +++ a/mm/page-writeback.c |
| @@ -70,30 +70,33 @@ static long ratelimit_pages = 32; |
| /* |
| * Start background writeback (via writeback threads) at this percentage |
| */ |
| -int dirty_background_ratio = 10; |
| +static int dirty_background_ratio = 10; |
| |
| /* |
| * dirty_background_bytes starts at 0 (disabled) so that it is a function of |
| * dirty_background_ratio * the amount of dirtyable memory |
| */ |
| -unsigned long dirty_background_bytes; |
| +static unsigned long dirty_background_bytes; |
| |
| /* |
| * free highmem will not be subtracted from the total free memory |
| * for calculating free ratios if vm_highmem_is_dirtyable is true |
| */ |
| -int vm_highmem_is_dirtyable; |
| +static int vm_highmem_is_dirtyable; |
| |
| /* |
| * The generator of dirty data starts writeback at this percentage |
| */ |
| -int vm_dirty_ratio = 20; |
| +static int vm_dirty_ratio = 20; |
| + |
| +/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */ |
| +static const unsigned long dirty_bytes_min = 2 * PAGE_SIZE; |
| |
| /* |
| * vm_dirty_bytes starts at 0 (disabled) so that it is a function of |
| * vm_dirty_ratio * the amount of dirtyable memory |
| */ |
| -unsigned long vm_dirty_bytes; |
| +static unsigned long vm_dirty_bytes; |
| |
| /* |
| * The interval between `kupdate'-style writebacks |
| @@ -503,7 +506,8 @@ bool node_dirty_ok(struct pglist_data *p |
| return nr_pages <= limit; |
| } |
| |
| -int dirty_background_ratio_handler(struct ctl_table *table, int write, |
| +#ifdef CONFIG_SYSCTL |
| +static int dirty_background_ratio_handler(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| int ret; |
| @@ -514,7 +518,7 @@ int dirty_background_ratio_handler(struc |
| return ret; |
| } |
| |
| -int dirty_background_bytes_handler(struct ctl_table *table, int write, |
| +static int dirty_background_bytes_handler(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| int ret; |
| @@ -525,7 +529,7 @@ int dirty_background_bytes_handler(struc |
| return ret; |
| } |
| |
| -int dirty_ratio_handler(struct ctl_table *table, int write, void *buffer, |
| +static int dirty_ratio_handler(struct ctl_table *table, int write, void *buffer, |
| size_t *lenp, loff_t *ppos) |
| { |
| int old_ratio = vm_dirty_ratio; |
| @@ -539,7 +543,7 @@ int dirty_ratio_handler(struct ctl_table |
| return ret; |
| } |
| |
| -int dirty_bytes_handler(struct ctl_table *table, int write, |
| +static int dirty_bytes_handler(struct ctl_table *table, int write, |
| void *buffer, size_t *lenp, loff_t *ppos) |
| { |
| unsigned long old_bytes = vm_dirty_bytes; |
| @@ -552,6 +556,7 @@ int dirty_bytes_handler(struct ctl_table |
| } |
| return ret; |
| } |
| +#endif |
| |
| static unsigned long wp_next_time(unsigned long cur_time) |
| { |
| @@ -1993,10 +1998,11 @@ bool wb_over_bg_thresh(struct bdi_writeb |
| return false; |
| } |
| |
| +#ifdef CONFIG_SYSCTL |
| /* |
| * sysctl handler for /proc/sys/vm/dirty_writeback_centisecs |
| */ |
| -int dirty_writeback_centisecs_handler(struct ctl_table *table, int write, |
| +static int dirty_writeback_centisecs_handler(struct ctl_table *table, int write, |
| void *buffer, size_t *length, loff_t *ppos) |
| { |
| unsigned int old_interval = dirty_writeback_interval; |
| @@ -2017,6 +2023,7 @@ int dirty_writeback_centisecs_handler(st |
| |
| return ret; |
| } |
| +#endif |
| |
| void laptop_mode_timer_fn(struct timer_list *t) |
| { |
| @@ -2081,6 +2088,79 @@ static int page_writeback_cpu_online(uns |
| return 0; |
| } |
| |
| +#ifdef CONFIG_SYSCTL |
| +static struct ctl_table vm_page_writeback_sysctls[] = { |
| + { |
| + .procname = "dirty_background_ratio", |
| + .data = &dirty_background_ratio, |
| + .maxlen = sizeof(dirty_background_ratio), |
| + .mode = 0644, |
| + .proc_handler = dirty_background_ratio_handler, |
| + .extra1 = SYSCTL_ZERO, |
| + .extra2 = SYSCTL_ONE_HUNDRED, |
| + }, |
| + { |
| + .procname = "dirty_background_bytes", |
| + .data = &dirty_background_bytes, |
| + .maxlen = sizeof(dirty_background_bytes), |
| + .mode = 0644, |
| + .proc_handler = dirty_background_bytes_handler, |
| + .extra1 = SYSCTL_LONG_ONE, |
| + }, |
| + { |
| + .procname = "dirty_ratio", |
| + .data = &vm_dirty_ratio, |
| + .maxlen = sizeof(vm_dirty_ratio), |
| + .mode = 0644, |
| + .proc_handler = dirty_ratio_handler, |
| + .extra1 = SYSCTL_ZERO, |
| + .extra2 = SYSCTL_ONE_HUNDRED, |
| + }, |
| + { |
| + .procname = "dirty_bytes", |
| + .data = &vm_dirty_bytes, |
| + .maxlen = sizeof(vm_dirty_bytes), |
| + .mode = 0644, |
| + .proc_handler = dirty_bytes_handler, |
| + .extra1 = (void *)&dirty_bytes_min, |
| + }, |
| + { |
| + .procname = "dirty_writeback_centisecs", |
| + .data = &dirty_writeback_interval, |
| + .maxlen = sizeof(dirty_writeback_interval), |
| + .mode = 0644, |
| + .proc_handler = dirty_writeback_centisecs_handler, |
| + }, |
| + { |
| + .procname = "dirty_expire_centisecs", |
| + .data = &dirty_expire_interval, |
| + .maxlen = sizeof(dirty_expire_interval), |
| + .mode = 0644, |
| + .proc_handler = proc_dointvec_minmax, |
| + .extra1 = SYSCTL_ZERO, |
| + }, |
| +#ifdef CONFIG_HIGHMEM |
| + { |
| + .procname = "highmem_is_dirtyable", |
| + .data = &vm_highmem_is_dirtyable, |
| + .maxlen = sizeof(vm_highmem_is_dirtyable), |
| + .mode = 0644, |
| + .proc_handler = proc_dointvec_minmax, |
| + .extra1 = SYSCTL_ZERO, |
| + .extra2 = SYSCTL_ONE, |
| + }, |
| +#endif |
| + { |
| + .procname = "laptop_mode", |
| + .data = &laptop_mode, |
| + .maxlen = sizeof(laptop_mode), |
| + .mode = 0644, |
| + .proc_handler = proc_dointvec_jiffies, |
| + }, |
| + {} |
| +}; |
| +#endif |
| + |
| /* |
| * Called early on to tune the page writeback dirty limits. |
| * |
| @@ -2105,6 +2185,9 @@ void __init page_writeback_init(void) |
| page_writeback_cpu_online, NULL); |
| cpuhp_setup_state(CPUHP_MM_WRITEBACK_DEAD, "mm/writeback:dead", NULL, |
| page_writeback_cpu_online); |
| +#ifdef CONFIG_SYSCTL |
| + register_sysctl_init("vm", vm_page_writeback_sysctls); |
| +#endif |
| } |
| |
| /** |
| _ |
