From: Minghao Chi <chi.minghao@xxxxxxxxxx> This moves all compaction sysctls to its own file. Move sysctl to where the functionality truly belongs to improve readability, reduce merge conflicts, and facilitate maintenance. I use x86_defconfig and linux-next-20230327 branch $ make defconfig;make all -jn CONFIG_COMPACTION=y add/remove: 1/0 grow/shrink: 1/1 up/down: 350/-256 (94) Function old new delta vm_compaction - 320 +320 kcompactd_init 180 210 +30 vm_table 2112 1856 -256 Total: Before=21119987, After=21120081, chg +0.00% Despite the addition of 94 bytes the patch still seems a worthwile cleanup. Link: https://lore.kernel.org/lkml/067f7347-ba10-5405-920c-0f5f985c84f4@xxxxxxx/ Signed-off-by: Minghao Chi <chi.minghao@xxxxxxxxxx> --- include/linux/compaction.h | 7 ---- kernel/sysctl.c | 59 -------------------------- mm/compaction.c | 84 ++++++++++++++++++++++++++++++++------ 3 files changed, 72 insertions(+), 78 deletions(-) diff --git a/include/linux/compaction.h b/include/linux/compaction.h index 52a9ff65faee..a6e512cfb670 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -81,13 +81,6 @@ static inline unsigned long compact_gap(unsigned int order) } #ifdef CONFIG_COMPACTION -extern unsigned int sysctl_compaction_proactiveness; -extern int sysctl_compaction_handler(struct ctl_table *table, int write, - void *buffer, size_t *length, loff_t *ppos); -extern int compaction_proactiveness_sysctl_handler(struct ctl_table *table, - int write, void *buffer, size_t *length, loff_t *ppos); -extern int sysctl_extfrag_threshold; -extern int sysctl_compact_unevictable_allowed; extern unsigned int extfrag_for_order(struct zone *zone, unsigned int order); extern int fragmentation_index(struct zone *zone, unsigned int order); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0a8a3c9c82e4..bfe53e835524 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -42,7 +42,6 @@ #include <linux/highuid.h> #include <linux/writeback.h> #include <linux/ratelimit.h> -#include <linux/compaction.h> #include <linux/hugetlb.h> #include <linux/initrd.h> #include <linux/key.h> @@ -746,27 +745,6 @@ int proc_dointvec(struct ctl_table *table, int write, void *buffer, return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL); } -#ifdef CONFIG_COMPACTION -static int proc_dointvec_minmax_warn_RT_change(struct ctl_table *table, - int write, void *buffer, size_t *lenp, loff_t *ppos) -{ - int ret, old; - - if (!IS_ENABLED(CONFIG_PREEMPT_RT) || !write) - return proc_dointvec_minmax(table, write, buffer, lenp, ppos); - - old = *(int *)table->data; - ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); - if (ret) - return ret; - if (old != *(int *)table->data) - pr_warn_once("sysctl attribute %s changed by %s[%d]\n", - table->procname, current->comm, - task_pid_nr(current)); - return ret; -} -#endif - /** * proc_douintvec - read a vector of unsigned integers * @table: the sysctl table @@ -2157,43 +2135,6 @@ static struct ctl_table vm_table[] = { .extra1 = SYSCTL_ONE, .extra2 = SYSCTL_FOUR, }, -#ifdef CONFIG_COMPACTION - { - .procname = "compact_memory", - .data = NULL, - .maxlen = sizeof(int), - .mode = 0200, - .proc_handler = sysctl_compaction_handler, - }, - { - .procname = "compaction_proactiveness", - .data = &sysctl_compaction_proactiveness, - .maxlen = sizeof(sysctl_compaction_proactiveness), - .mode = 0644, - .proc_handler = compaction_proactiveness_sysctl_handler, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE_HUNDRED, - }, - { - .procname = "extfrag_threshold", - .data = &sysctl_extfrag_threshold, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE_THOUSAND, - }, - { - .procname = "compact_unevictable_allowed", - .data = &sysctl_compact_unevictable_allowed, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec_minmax_warn_RT_change, - .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, - }, - -#endif /* CONFIG_COMPACTION */ { .procname = "min_free_kbytes", .data = &min_free_kbytes, diff --git a/mm/compaction.c b/mm/compaction.c index e689d66cedf4..3dfdb84b9c98 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1728,7 +1728,14 @@ typedef enum { * Allow userspace to control policy on scanning the unevictable LRU for * compactable pages. */ -int sysctl_compact_unevictable_allowed __read_mostly = CONFIG_COMPACT_UNEVICTABLE_DEFAULT; +static int sysctl_compact_unevictable_allowed __read_mostly = CONFIG_COMPACT_UNEVICTABLE_DEFAULT; +/* + * Tunable for proactive compaction. It determines how + * aggressively the kernel should compact memory in the + * background. It takes values in the range [0, 100]. + */ +static unsigned int __read_mostly sysctl_compaction_proactiveness = 20; +static int sysctl_extfrag_threshold = 500; static inline void update_fast_start_pfn(struct compact_control *cc, unsigned long pfn) @@ -2584,8 +2591,6 @@ static enum compact_result compact_zone_order(struct zone *zone, int order, return ret; } -int sysctl_extfrag_threshold = 500; - /** * try_to_compact_pages - Direct compact to satisfy a high-order allocation * @gfp_mask: The GFP mask of the current allocation @@ -2742,14 +2747,7 @@ static void compact_nodes(void) compact_node(nid); } -/* - * Tunable for proactive compaction. It determines how - * aggressively the kernel should compact memory in the - * background. It takes values in the range [0, 100]. - */ -unsigned int __read_mostly sysctl_compaction_proactiveness = 20; - -int compaction_proactiveness_sysctl_handler(struct ctl_table *table, int write, +static int compaction_proactiveness_sysctl_handler(struct ctl_table *table, int write, void *buffer, size_t *length, loff_t *ppos) { int rc, nid; @@ -2779,7 +2777,7 @@ int compaction_proactiveness_sysctl_handler(struct ctl_table *table, int write, * This is the entry point for compacting all nodes via * /proc/sys/vm/compact_memory */ -int sysctl_compaction_handler(struct ctl_table *table, int write, +static int sysctl_compaction_handler(struct ctl_table *table, int write, void *buffer, size_t *length, loff_t *ppos) { if (write) @@ -3075,6 +3073,65 @@ static int kcompactd_cpu_online(unsigned int cpu) return 0; } +static int proc_dointvec_minmax_warn_RT_change(struct ctl_table *table, + int write, void *buffer, size_t *lenp, loff_t *ppos) +{ + int ret, old; + + if (!IS_ENABLED(CONFIG_PREEMPT_RT) || !write) + return proc_dointvec_minmax(table, write, buffer, lenp, ppos); + + old = *(int *)table->data; + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + if (ret) + return ret; + if (old != *(int *)table->data) + pr_warn_once("sysctl attribute %s changed by %s[%d]\n", + table->procname, current->comm, + task_pid_nr(current)); + return ret; +} + +#ifdef CONFIG_SYSCTL +static struct ctl_table vm_compaction[] = { + { + .procname = "compact_memory", + .data = NULL, + .maxlen = sizeof(int), + .mode = 0200, + .proc_handler = sysctl_compaction_handler, + }, + { + .procname = "compaction_proactiveness", + .data = &sysctl_compaction_proactiveness, + .maxlen = sizeof(sysctl_compaction_proactiveness), + .mode = 0644, + .proc_handler = compaction_proactiveness_sysctl_handler, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE_HUNDRED, + }, + { + .procname = "extfrag_threshold", + .data = &sysctl_extfrag_threshold, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE_THOUSAND, + }, + { + .procname = "compact_unevictable_allowed", + .data = &sysctl_compact_unevictable_allowed, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax_warn_RT_change, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { } +}; +#endif + static int __init kcompactd_init(void) { int nid; @@ -3090,6 +3147,9 @@ static int __init kcompactd_init(void) for_each_node_state(nid, N_MEMORY) kcompactd_run(nid); +#ifdef CONFIG_SYSCTL + register_sysctl_init("vm", vm_compaction); +#endif return 0; } subsys_initcall(kcompactd_init) -- 2.25.1
