From 48fe8ab8d5a39c7bc49cb41d0ad92c75f48a9550 Mon Sep 17 00:00:00 2001 From: Minghao Chi Date: Tue, 28 Mar 2023 14:46:28 +0800 Subject: mm: compaction: move compaction sysctl to its own file 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@suse.cz/ Signed-off-by: Minghao Chi Acked-by: Vlastimil Babka Signed-off-by: Luis Chamberlain --- mm/compaction.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 72 insertions(+), 12 deletions(-) (limited to 'mm/compaction.c') diff --git a/mm/compaction.c b/mm/compaction.c index 5a9501e0ae01..f2ddfb1140e2 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1716,7 +1716,14 @@ 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) @@ -2572,8 +2579,6 @@ 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 @@ -2730,14 +2735,7 @@ 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; @@ -2767,7 +2765,7 @@ 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) @@ -3063,6 +3061,65 @@ 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; @@ -3078,6 +3135,9 @@ 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) -- cgit v1.2.3-58-ga151