[PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[Kaixiong Yu]

This patch series moves sysctls of vm_table in kernel/sysctl.c to
places where they actually belong, and do some related code clean-ups.
After this patch series, all sysctls in vm_table have been moved into its
own files, meanwhile, delete vm_table.

All the modifications of this patch series base on
linux-next(tags/next-20241010). To test this patch series, the code was
compiled with both the CONFIG_SYSCTL enabled and disabled on arm64 and
x86_64 architectures. After this patch series is applied, all files
under /proc/sys/vm can be read or written normally.

Changes in v3:
 - change patch1~10, patch14 title suggested by Joel Granados
 - change sysctl_stat_interval to static type in patch1
 - add acked-by from Paul Moore in patch7
 - change dirtytime_expire_interval to static type in patch9
 - add acked-by from Anna Schumaker in patch11

Changes in v2:
 - fix sysctl_max_map_count undeclared issue in mm/nommu.c for patch6
 - update changelog for patch7/12, suggested by Kees/Paul
 - fix patch8, sorry for wrong changes and forget to built with NOMMU
 - add reviewed-by from Kees except patch8 since patch8 is wrong in v1
 - add reviewed-by from Jan Kara, Christian Brauner in patch12

Kaixiong Yu (15):
  mm: vmstat: move sysctls to mm/vmstat.c
  mm: filemap: move sysctl to mm/filemap.c
  mm: swap: move sysctl to mm/swap.c
  mm: vmscan: move vmscan sysctls to mm/vmscan.c
  mm: util: move sysctls to mm/util.c
  mm: mmap: move sysctl to mm/mmap.c
  security: min_addr: move sysctl to security/min_addr.c
  mm: nommu: move sysctl to mm/nommu.c
  fs: fs-writeback: move sysctl to fs/fs-writeback.c
  fs: drop_caches: move sysctl to fs/drop_caches.c
  sunrpc: use vfs_pressure_ratio() helper
  fs: dcache: move the sysctl to fs/dcache.c
  x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c
  sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c
  sysctl: remove unneeded include

 arch/sh/kernel/vsyscall/vsyscall.c |  14 ++
 arch/x86/entry/vdso/vdso32-setup.c |  16 ++-
 fs/dcache.c                        |  21 ++-
 fs/drop_caches.c                   |  23 ++-
 fs/fs-writeback.c                  |  30 ++--
 include/linux/dcache.h             |   7 +-
 include/linux/mm.h                 |  23 ---
 include/linux/mman.h               |   2 -
 include/linux/swap.h               |   9 --
 include/linux/vmstat.h             |  11 --
 include/linux/writeback.h          |   4 -
 kernel/sysctl.c                    | 221 -----------------------------
 mm/filemap.c                       |  18 ++-
 mm/internal.h                      |  10 ++
 mm/mmap.c                          |  54 +++++++
 mm/nommu.c                         |  15 +-
 mm/swap.c                          |  16 ++-
 mm/swap.h                          |   1 +
 mm/util.c                          |  67 +++++++--
 mm/vmscan.c                        |  23 +++
 mm/vmstat.c                        |  44 +++++-
 net/sunrpc/auth.c                  |   2 +-
 security/min_addr.c                |  11 ++
 23 files changed, 330 insertions(+), 312 deletions(-)

-- 
2.34.1

[PATCH v3 -next 01/15] mm: vmstat: move sysctls to mm/vmstat.c

[Kaixiong Yu]

This moves all vmstat related sysctls to its own file, removes useless
extern variable declarations, and do some related clean-ups. To avoid
compiler warnings when CONFIG_PROC_FS is not defined, add the macro
definition CONFIG_PROC_FS ahead CONFIG_NUMA in vmstat.c.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
 - change sysctl_stat_interval to static type
---
 include/linux/vmstat.h | 11 -----------
 kernel/sysctl.c        | 28 ---------------------------
 mm/vmstat.c            | 44 ++++++++++++++++++++++++++++++++++++++----
 3 files changed, 40 insertions(+), 43 deletions(-)

diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index d2761bf8ff32..b2ccb6845595 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -10,15 +10,8 @@
 #include <linux/static_key.h>
 #include <linux/mmdebug.h>
 
-extern int sysctl_stat_interval;
-
 #ifdef CONFIG_NUMA
-#define ENABLE_NUMA_STAT   1
-#define DISABLE_NUMA_STAT   0
-extern int sysctl_vm_numa_stat;
 DECLARE_STATIC_KEY_TRUE(vm_numa_stat_key);
-int sysctl_vm_numa_stat_handler(const struct ctl_table *table, int write,
-		void *buffer, size_t *length, loff_t *ppos);
 #endif
 
 struct reclaim_stat {
@@ -304,10 +297,6 @@ void quiet_vmstat(void);
 void cpu_vm_stats_fold(int cpu);
 void refresh_zone_stat_thresholds(void);
 
-struct ctl_table;
-int vmstat_refresh(const struct ctl_table *, int write, void *buffer, size_t *lenp,
-		loff_t *ppos);
-
 void drain_zonestat(struct zone *zone, struct per_cpu_zonestat *);
 
 int calculate_pressure_threshold(struct zone *zone);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 79e6cb1d5c48..726b866af57b 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -49,7 +49,6 @@
 #include <linux/limits.h>
 #include <linux/dcache.h>
 #include <linux/syscalls.h>
-#include <linux/vmstat.h>
 #include <linux/nfs_fs.h>
 #include <linux/acpi.h>
 #include <linux/reboot.h>
@@ -2081,17 +2080,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_TWO_HUNDRED,
 	},
-#ifdef CONFIG_NUMA
-	{
-		.procname	= "numa_stat",
-		.data		= &sysctl_vm_numa_stat,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= sysctl_vm_numa_stat_handler,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_ONE,
-	},
-#endif
 	{
 		.procname	= "drop_caches",
 		.data		= &sysctl_drop_caches,
@@ -2157,22 +2145,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ZERO,
 	},
 #endif
-#ifdef CONFIG_SMP
-	{
-		.procname	= "stat_interval",
-		.data		= &sysctl_stat_interval,
-		.maxlen		= sizeof(sysctl_stat_interval),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_jiffies,
-	},
-	{
-		.procname	= "stat_refresh",
-		.data		= NULL,
-		.maxlen		= 0,
-		.mode		= 0600,
-		.proc_handler	= vmstat_refresh,
-	},
-#endif
 #ifdef CONFIG_MMU
 	{
 		.procname	= "mmap_min_addr",
diff --git a/mm/vmstat.c b/mm/vmstat.c
index bb081ae4d0ae..25cb31545bc0 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -31,8 +31,10 @@
 
 #include "internal.h"
 
+#ifdef CONFIG_PROC_FS
 #ifdef CONFIG_NUMA
-int sysctl_vm_numa_stat = ENABLE_NUMA_STAT;
+#define ENABLE_NUMA_STAT 1
+static int sysctl_vm_numa_stat = ENABLE_NUMA_STAT;
 
 /* zero numa counters within a zone */
 static void zero_zone_numa_counters(struct zone *zone)
@@ -74,7 +76,7 @@ static void invalid_numa_statistics(void)
 
 static DEFINE_MUTEX(vm_numa_stat_lock);
 
-int sysctl_vm_numa_stat_handler(const struct ctl_table *table, int write,
+static int sysctl_vm_numa_stat_handler(const struct ctl_table *table, int write,
 		void *buffer, size_t *length, loff_t *ppos)
 {
 	int ret, oldval;
@@ -102,6 +104,7 @@ int sysctl_vm_numa_stat_handler(const struct ctl_table *table, int write,
 	return ret;
 }
 #endif
+#endif /* CONFIG_PROC_FS */
 
 #ifdef CONFIG_VM_EVENT_COUNTERS
 DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
@@ -1928,7 +1931,7 @@ static const struct seq_operations vmstat_op = {
 
 #ifdef CONFIG_SMP
 static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
-int sysctl_stat_interval __read_mostly = HZ;
+static int sysctl_stat_interval __read_mostly = HZ;
 static int vmstat_late_init_done;
 
 #ifdef CONFIG_PROC_FS
@@ -1937,7 +1940,7 @@ static void refresh_vm_stats(struct work_struct *work)
 	refresh_cpu_vm_stats(true);
 }
 
-int vmstat_refresh(const struct ctl_table *table, int write,
+static int vmstat_refresh(const struct ctl_table *table, int write,
 		   void *buffer, size_t *lenp, loff_t *ppos)
 {
 	long val;
@@ -2175,6 +2178,38 @@ static int __init vmstat_late_init(void)
 late_initcall(vmstat_late_init);
 #endif
 
+#ifdef CONFIG_PROC_FS
+static struct ctl_table vmstat_table[] = {
+#ifdef CONFIG_SMP
+	{
+		.procname	= "stat_interval",
+		.data		= &sysctl_stat_interval,
+		.maxlen		= sizeof(sysctl_stat_interval),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{
+		.procname	= "stat_refresh",
+		.data		= NULL,
+		.maxlen		= 0,
+		.mode		= 0600,
+		.proc_handler	= vmstat_refresh,
+	},
+#endif
+#ifdef CONFIG_NUMA
+	{
+		.procname	= "numa_stat",
+		.data		= &sysctl_vm_numa_stat,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= sysctl_vm_numa_stat_handler,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_ONE,
+	},
+#endif
+};
+#endif
+
 struct workqueue_struct *mm_percpu_wq;
 
 void __init init_mm_internals(void)
@@ -2206,6 +2241,7 @@ void __init init_mm_internals(void)
 	proc_create_seq("pagetypeinfo", 0400, NULL, &pagetypeinfo_op);
 	proc_create_seq("vmstat", 0444, NULL, &vmstat_op);
 	proc_create_seq("zoneinfo", 0444, NULL, &zoneinfo_op);
+	register_sysctl_init("vm", vmstat_table);
 #endif
 }
 
-- 
2.34.1

[PATCH v3 -next 02/15] mm: filemap: move sysctl to mm/filemap.c

[Kaixiong Yu]

This moves the filemap related sysctl to mm/filemap.c, and
removes the redundant external variable declaration.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
---
 include/linux/mm.h |  2 --
 kernel/sysctl.c    |  8 --------
 mm/filemap.c       | 18 +++++++++++++++---
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index df0a5eac66b7..a3c3a7d64407 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -39,8 +39,6 @@ struct user_struct;
 struct pt_regs;
 struct folio_batch;
 
-extern int sysctl_page_lock_unfairness;
-
 void mm_core_init(void);
 void init_mm_internals(void);
 
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 726b866af57b..2a875b739054 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2089,14 +2089,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ONE,
 		.extra2		= SYSCTL_FOUR,
 	},
-	{
-		.procname	= "page_lock_unfairness",
-		.data		= &sysctl_page_lock_unfairness,
-		.maxlen		= sizeof(sysctl_page_lock_unfairness),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-	},
 #ifdef CONFIG_MMU
 	{
 		.procname	= "max_map_count",
diff --git a/mm/filemap.c b/mm/filemap.c
index 429895f1a564..0d4adf8068ca 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -47,6 +47,7 @@
 #include <linux/splice.h>
 #include <linux/rcupdate_wait.h>
 #include <linux/sched/mm.h>
+#include <linux/sysctl.h>
 #include <asm/pgalloc.h>
 #include <asm/tlbflush.h>
 #include "internal.h"
@@ -1069,6 +1070,19 @@ static wait_queue_head_t *folio_waitqueue(struct folio *folio)
 	return &folio_wait_table[hash_ptr(folio, PAGE_WAIT_TABLE_BITS)];
 }
 
+/* How many times do we accept lock stealing from under a waiter? */
+static int sysctl_page_lock_unfairness = 5;
+static struct ctl_table filemap_sysctl_table[] = {
+	{
+		.procname	= "page_lock_unfairness",
+		.data		= &sysctl_page_lock_unfairness,
+		.maxlen		= sizeof(sysctl_page_lock_unfairness),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+	}
+};
+
 void __init pagecache_init(void)
 {
 	int i;
@@ -1077,6 +1091,7 @@ void __init pagecache_init(void)
 		init_waitqueue_head(&folio_wait_table[i]);
 
 	page_writeback_init();
+	register_sysctl_init("vm", filemap_sysctl_table);
 }
 
 /*
@@ -1224,9 +1239,6 @@ static inline bool folio_trylock_flag(struct folio *folio, int bit_nr,
 	return true;
 }
 
-/* How many times do we accept lock stealing from under a waiter? */
-int sysctl_page_lock_unfairness = 5;
-
 static inline int folio_wait_bit_common(struct folio *folio, int bit_nr,
 		int state, enum behavior behavior)
 {
-- 
2.34.1

[PATCH v3 -next 03/15] mm: swap: move sysctl to mm/swap.c

[Kaixiong Yu]

The page-cluster belongs to mm/swap.c, move it to mm/swap.c .
Removes the redundant external variable declaration and unneeded
include(linux/swap.h).

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
---
 include/linux/mm.h |  2 --
 kernel/sysctl.c    | 10 ----------
 mm/swap.c          | 16 +++++++++++++++-
 mm/swap.h          |  1 +
 4 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index a3c3a7d64407..7c46de4290da 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -75,8 +75,6 @@ static inline void totalram_pages_add(long count)
 }
 
 extern void * high_memory;
-extern int page_cluster;
-extern const int page_cluster_max;
 
 #ifdef CONFIG_SYSCTL
 extern int sysctl_legacy_va_layout;
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 2a875b739054..9fad501311a1 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -21,7 +21,6 @@
 
 #include <linux/module.h>
 #include <linux/mm.h>
-#include <linux/swap.h>
 #include <linux/slab.h>
 #include <linux/sysctl.h>
 #include <linux/bitmap.h>
@@ -2054,15 +2053,6 @@ static struct ctl_table vm_table[] = {
 		.mode		= 0644,
 		.proc_handler	= overcommit_kbytes_handler,
 	},
-	{
-		.procname	= "page-cluster",
-		.data		= &page_cluster,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= (void *)&page_cluster_max,
-	},
 	{
 		.procname	= "dirtytime_expire_seconds",
 		.data		= &dirtytime_expire_interval,
diff --git a/mm/swap.c b/mm/swap.c
index 835bdf324b76..2f7d415e66a3 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -45,7 +45,7 @@
 
 /* How many pages do we try to swap or page in/out together? As a power of 2 */
 int page_cluster;
-const int page_cluster_max = 31;
+static const int page_cluster_max = 31;
 
 struct cpu_fbatches {
 	/*
@@ -1089,6 +1089,18 @@ void folio_batch_remove_exceptionals(struct folio_batch *fbatch)
 	fbatch->nr = j;
 }
 
+static struct ctl_table swap_sysctl_table[] = {
+	{
+		.procname	= "page-cluster",
+		.data		= &page_cluster,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= (void *)&page_cluster_max,
+	}
+};
+
 /*
  * Perform any setup for the swap system
  */
@@ -1105,4 +1117,6 @@ void __init swap_setup(void)
 	 * Right now other parts of the system means that we
 	 * _really_ don't want to cluster much more
 	 */
+
+	register_sysctl_init("vm", swap_sysctl_table);
 }
diff --git a/mm/swap.h b/mm/swap.h
index ad2f121de970..274dcc6219a0 100644
--- a/mm/swap.h
+++ b/mm/swap.h
@@ -3,6 +3,7 @@
 #define _MM_SWAP_H
 
 struct mempolicy;
+extern int page_cluster;
 
 #ifdef CONFIG_SWAP
 #include <linux/swapops.h> /* for swp_offset */
-- 
2.34.1

[PATCH v3 -next 04/15] mm: vmscan: move vmscan sysctls to mm/vmscan.c

[Kaixiong Yu]

This moves vm_swappiness and zone_reclaim_mode to mm/vmscan.c,
as part of the kernel/sysctl.c cleaning, also moves some external
variable declarations and function declarations from include/linux/swap.h
into mm/internal.h.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
---
 include/linux/swap.h |  9 ---------
 kernel/sysctl.c      | 19 -------------------
 mm/internal.h        | 10 ++++++++++
 mm/vmscan.c          | 23 +++++++++++++++++++++++
 4 files changed, 33 insertions(+), 28 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index ca533b478c21..c95fb8d87b05 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -425,19 +425,10 @@ extern int vm_swappiness;
 long remove_mapping(struct address_space *mapping, struct folio *folio);
 
 #ifdef CONFIG_NUMA
-extern int node_reclaim_mode;
 extern int sysctl_min_unmapped_ratio;
 extern int sysctl_min_slab_ratio;
-#else
-#define node_reclaim_mode 0
 #endif
 
-static inline bool node_reclaim_enabled(void)
-{
-	/* Is any node_reclaim_mode bit set? */
-	return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP);
-}
-
 void check_move_unevictable_folios(struct folio_batch *fbatch);
 
 extern void __meminit kswapd_run(int nid);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 9fad501311a1..184d39944e16 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2061,15 +2061,6 @@ static struct ctl_table vm_table[] = {
 		.proc_handler	= dirtytime_interval_handler,
 		.extra1		= SYSCTL_ZERO,
 	},
-	{
-		.procname	= "swappiness",
-		.data		= &vm_swappiness,
-		.maxlen		= sizeof(vm_swappiness),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_TWO_HUNDRED,
-	},
 	{
 		.procname	= "drop_caches",
 		.data		= &sysctl_drop_caches,
@@ -2117,16 +2108,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ZERO,
 	},
 #endif
-#ifdef CONFIG_NUMA
-	{
-		.procname	= "zone_reclaim_mode",
-		.data		= &node_reclaim_mode,
-		.maxlen		= sizeof(node_reclaim_mode),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-	},
-#endif
 #ifdef CONFIG_MMU
 	{
 		.procname	= "mmap_min_addr",
diff --git a/mm/internal.h b/mm/internal.h
index 906da6280c2d..84c46fe6a07c 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1038,9 +1038,13 @@ static inline void mminit_verify_zonelist(void)
 #define NODE_RECLAIM_SUCCESS	1
 
 #ifdef CONFIG_NUMA
+extern int node_reclaim_mode;
+
 extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);
 extern int find_next_best_node(int node, nodemask_t *used_node_mask);
 #else
+#define node_reclaim_mode 0
+
 static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,
 				unsigned int order)
 {
@@ -1052,6 +1056,12 @@ static inline int find_next_best_node(int node, nodemask_t *used_node_mask)
 }
 #endif
 
+static inline bool node_reclaim_enabled(void)
+{
+	/* Is any node_reclaim_mode bit set? */
+	return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP);
+}
+
 /*
  * mm/memory-failure.c
  */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f9919b522c01..1188978e46d5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -7384,6 +7384,28 @@ void __meminit kswapd_stop(int nid)
 	pgdat_kswapd_unlock(pgdat);
 }
 
+static struct ctl_table vmscan_sysctl_table[] = {
+	{
+		.procname	= "swappiness",
+		.data		= &vm_swappiness,
+		.maxlen		= sizeof(vm_swappiness),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_TWO_HUNDRED,
+	},
+#ifdef CONFIG_NUMA
+	{
+		.procname	= "zone_reclaim_mode",
+		.data		= &node_reclaim_mode,
+		.maxlen		= sizeof(node_reclaim_mode),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+	}
+#endif
+};
+
 static int __init kswapd_init(void)
 {
 	int nid;
@@ -7391,6 +7413,7 @@ static int __init kswapd_init(void)
 	swap_setup();
 	for_each_node_state(nid, N_MEMORY)
  		kswapd_run(nid);
+	register_sysctl_init("vm", vmscan_sysctl_table);
 	return 0;
 }
 
-- 
2.34.1

[PATCH v3 -next 05/15] mm: util: move sysctls to mm/util.c

[Kaixiong Yu]

This moves all util related sysctls to mm/util.c, as part of the
kernel/sysctl.c cleaning, also removes redundant external
variable declarations and function declarations.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
---
 include/linux/mm.h   | 11 --------
 include/linux/mman.h |  2 --
 kernel/sysctl.c      | 37 ------------------------
 mm/util.c            | 67 ++++++++++++++++++++++++++++++++++++++------
 4 files changed, 59 insertions(+), 58 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7c46de4290da..50f0069280f4 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -204,17 +204,6 @@ extern int sysctl_max_map_count;
 extern unsigned long sysctl_user_reserve_kbytes;
 extern unsigned long sysctl_admin_reserve_kbytes;
 
-extern int sysctl_overcommit_memory;
-extern int sysctl_overcommit_ratio;
-extern unsigned long sysctl_overcommit_kbytes;
-
-int overcommit_ratio_handler(const struct ctl_table *, int, void *, size_t *,
-		loff_t *);
-int overcommit_kbytes_handler(const struct ctl_table *, int, void *, size_t *,
-		loff_t *);
-int overcommit_policy_handler(const struct ctl_table *, int, void *, size_t *,
-		loff_t *);
-
 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
 #define folio_page_idx(folio, p)	(page_to_pfn(p) - folio_pfn(folio))
diff --git a/include/linux/mman.h b/include/linux/mman.h
index bcb201ab7a41..e62ef272d140 100644
--- a/include/linux/mman.h
+++ b/include/linux/mman.h
@@ -58,8 +58,6 @@
 		| MAP_HUGE_1GB)
 
 extern int sysctl_overcommit_memory;
-extern int sysctl_overcommit_ratio;
-extern unsigned long sysctl_overcommit_kbytes;
 extern struct percpu_counter vm_committed_as;
 
 #ifdef CONFIG_SMP
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 184d39944e16..ad3ac6f6c808 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2030,29 +2030,6 @@ static struct ctl_table kern_table[] = {
 };
 
 static struct ctl_table vm_table[] = {
-	{
-		.procname	= "overcommit_memory",
-		.data		= &sysctl_overcommit_memory,
-		.maxlen		= sizeof(sysctl_overcommit_memory),
-		.mode		= 0644,
-		.proc_handler	= overcommit_policy_handler,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_TWO,
-	},
-	{
-		.procname	= "overcommit_ratio",
-		.data		= &sysctl_overcommit_ratio,
-		.maxlen		= sizeof(sysctl_overcommit_ratio),
-		.mode		= 0644,
-		.proc_handler	= overcommit_ratio_handler,
-	},
-	{
-		.procname	= "overcommit_kbytes",
-		.data		= &sysctl_overcommit_kbytes,
-		.maxlen		= sizeof(sysctl_overcommit_kbytes),
-		.mode		= 0644,
-		.proc_handler	= overcommit_kbytes_handler,
-	},
 	{
 		.procname	= "dirtytime_expire_seconds",
 		.data		= &dirtytime_expire_interval,
@@ -2133,20 +2110,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ZERO,
 	},
 #endif
-	{
-		.procname	= "user_reserve_kbytes",
-		.data		= &sysctl_user_reserve_kbytes,
-		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
-		.mode		= 0644,
-		.proc_handler	= proc_doulongvec_minmax,
-	},
-	{
-		.procname	= "admin_reserve_kbytes",
-		.data		= &sysctl_admin_reserve_kbytes,
-		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
-		.mode		= 0644,
-		.proc_handler	= proc_doulongvec_minmax,
-	},
 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
 	{
 		.procname	= "mmap_rnd_bits",
diff --git a/mm/util.c b/mm/util.c
index c1c3b06ab4f9..d0c5f5110aa1 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -12,6 +12,7 @@
 #include <linux/security.h>
 #include <linux/swap.h>
 #include <linux/swapops.h>
+#include <linux/sysctl.h>
 #include <linux/mman.h>
 #include <linux/hugetlb.h>
 #include <linux/vmalloc.h>
@@ -894,14 +895,16 @@ int folio_mc_copy(struct folio *dst, struct folio *src)
 EXPORT_SYMBOL(folio_mc_copy);
 
 int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_GUESS;
-int sysctl_overcommit_ratio __read_mostly = 50;
-unsigned long sysctl_overcommit_kbytes __read_mostly;
+static int sysctl_overcommit_ratio __read_mostly = 50;
+static unsigned long sysctl_overcommit_kbytes __read_mostly;
 int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;
 unsigned long sysctl_user_reserve_kbytes __read_mostly = 1UL << 17; /* 128MB */
 unsigned long sysctl_admin_reserve_kbytes __read_mostly = 1UL << 13; /* 8MB */
 
-int overcommit_ratio_handler(const struct ctl_table *table, int write, void *buffer,
-		size_t *lenp, loff_t *ppos)
+#ifdef CONFIG_SYSCTL
+
+static int overcommit_ratio_handler(const struct ctl_table *table, int write,
+				void *buffer, size_t *lenp, loff_t *ppos)
 {
 	int ret;
 
@@ -916,8 +919,8 @@ static void sync_overcommit_as(struct work_struct *dummy)
 	percpu_counter_sync(&vm_committed_as);
 }
 
-int overcommit_policy_handler(const struct ctl_table *table, int write, void *buffer,
-		size_t *lenp, loff_t *ppos)
+static int overcommit_policy_handler(const struct ctl_table *table, int write,
+				void *buffer, size_t *lenp, loff_t *ppos)
 {
 	struct ctl_table t;
 	int new_policy = -1;
@@ -952,8 +955,8 @@ int overcommit_policy_handler(const struct ctl_table *table, int write, void *bu
 	return ret;
 }
 
-int overcommit_kbytes_handler(const struct ctl_table *table, int write, void *buffer,
-		size_t *lenp, loff_t *ppos)
+static int overcommit_kbytes_handler(const struct ctl_table *table, int write,
+				void *buffer, size_t *lenp, loff_t *ppos)
 {
 	int ret;
 
@@ -963,6 +966,54 @@ int overcommit_kbytes_handler(const struct ctl_table *table, int write, void *bu
 	return ret;
 }
 
+static struct ctl_table util_sysctl_table[] = {
+	{
+		.procname	= "overcommit_memory",
+		.data		= &sysctl_overcommit_memory,
+		.maxlen		= sizeof(sysctl_overcommit_memory),
+		.mode		= 0644,
+		.proc_handler	= overcommit_policy_handler,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_TWO,
+	},
+	{
+		.procname	= "overcommit_ratio",
+		.data		= &sysctl_overcommit_ratio,
+		.maxlen		= sizeof(sysctl_overcommit_ratio),
+		.mode		= 0644,
+		.proc_handler	= overcommit_ratio_handler,
+	},
+	{
+		.procname	= "overcommit_kbytes",
+		.data		= &sysctl_overcommit_kbytes,
+		.maxlen		= sizeof(sysctl_overcommit_kbytes),
+		.mode		= 0644,
+		.proc_handler	= overcommit_kbytes_handler,
+	},
+	{
+		.procname	= "user_reserve_kbytes",
+		.data		= &sysctl_user_reserve_kbytes,
+		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+	},
+	{
+		.procname	= "admin_reserve_kbytes",
+		.data		= &sysctl_admin_reserve_kbytes,
+		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+	},
+};
+
+static int __init init_vm_util_sysctls(void)
+{
+	register_sysctl_init("vm", util_sysctl_table);
+	return 0;
+}
+subsys_initcall(init_vm_util_sysctls);
+#endif /* CONFIG_SYSCTL */
+
 /*
  * Committed memory limit enforced when OVERCOMMIT_NEVER policy is used
  */
-- 
2.34.1

[PATCH v3 -next 06/15] mm: mmap: move sysctl to mm/mmap.c

[Kaixiong Yu]

This moves all mmap related sysctls to mm/mmap.c, as part of the
kernel/sysctl.c cleaning, also move the variable declaration from
kernel/sysctl.c into mm/mmap.c.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
v2:
 - fix sysctl_max_map_count undeclared issue in mm/nommu.c
---
 kernel/sysctl.c | 50 +--------------------------------------------
 mm/mmap.c       | 54 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 49 deletions(-)

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index ad3ac6f6c808..41d4afc978e6 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -127,12 +127,6 @@ enum sysctl_writes_mode {
 
 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
 #endif /* CONFIG_PROC_SYSCTL */
-
-#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
-    defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
-int sysctl_legacy_va_layout;
-#endif
-
 #endif /* CONFIG_SYSCTL */
 
 /*
@@ -2047,16 +2041,7 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ONE,
 		.extra2		= SYSCTL_FOUR,
 	},
-#ifdef CONFIG_MMU
-	{
-		.procname	= "max_map_count",
-		.data		= &sysctl_max_map_count,
-		.maxlen		= sizeof(sysctl_max_map_count),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-	},
-#else
+#ifndef CONFIG_MMU
 	{
 		.procname	= "nr_trim_pages",
 		.data		= &sysctl_nr_trim_pages,
@@ -2074,17 +2059,6 @@ static struct ctl_table vm_table[] = {
 		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= SYSCTL_ZERO,
 	},
-#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
-    defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
-	{
-		.procname	= "legacy_va_layout",
-		.data		= &sysctl_legacy_va_layout,
-		.maxlen		= sizeof(sysctl_legacy_va_layout),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-	},
-#endif
 #ifdef CONFIG_MMU
 	{
 		.procname	= "mmap_min_addr",
@@ -2110,28 +2084,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ZERO,
 	},
 #endif
-#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
-	{
-		.procname	= "mmap_rnd_bits",
-		.data		= &mmap_rnd_bits,
-		.maxlen		= sizeof(mmap_rnd_bits),
-		.mode		= 0600,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= (void *)&mmap_rnd_bits_min,
-		.extra2		= (void *)&mmap_rnd_bits_max,
-	},
-#endif
-#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
-	{
-		.procname	= "mmap_rnd_compat_bits",
-		.data		= &mmap_rnd_compat_bits,
-		.maxlen		= sizeof(mmap_rnd_compat_bits),
-		.mode		= 0600,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= (void *)&mmap_rnd_compat_bits_min,
-		.extra2		= (void *)&mmap_rnd_compat_bits_max,
-	},
-#endif
 };
 
 int __init sysctl_init_bases(void)
diff --git a/mm/mmap.c b/mm/mmap.c
index 4ef58ad80a33..6d584e67d045 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2176,6 +2176,57 @@ struct vm_area_struct *_install_special_mapping(
 					&special_mapping_vmops);
 }
 
+#ifdef CONFIG_SYSCTL
+#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
+		defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
+int sysctl_legacy_va_layout;
+#endif
+
+static struct ctl_table mmap_table[] = {
+		{
+				.procname       = "max_map_count",
+				.data           = &sysctl_max_map_count,
+				.maxlen         = sizeof(sysctl_max_map_count),
+				.mode           = 0644,
+				.proc_handler   = proc_dointvec_minmax,
+				.extra1         = SYSCTL_ZERO,
+		},
+#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
+		defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
+		{
+				.procname       = "legacy_va_layout",
+				.data           = &sysctl_legacy_va_layout,
+				.maxlen         = sizeof(sysctl_legacy_va_layout),
+				.mode           = 0644,
+				.proc_handler   = proc_dointvec_minmax,
+				.extra1         = SYSCTL_ZERO,
+		},
+#endif
+#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
+		{
+				.procname       = "mmap_rnd_bits",
+				.data           = &mmap_rnd_bits,
+				.maxlen         = sizeof(mmap_rnd_bits),
+				.mode           = 0600,
+				.proc_handler   = proc_dointvec_minmax,
+				.extra1         = (void *)&mmap_rnd_bits_min,
+				.extra2         = (void *)&mmap_rnd_bits_max,
+		},
+#endif
+#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
+		{
+				.procname       = "mmap_rnd_compat_bits",
+				.data           = &mmap_rnd_compat_bits,
+				.maxlen         = sizeof(mmap_rnd_compat_bits),
+				.mode           = 0600,
+				.proc_handler   = proc_dointvec_minmax,
+				.extra1         = (void *)&mmap_rnd_compat_bits_min,
+				.extra2         = (void *)&mmap_rnd_compat_bits_max,
+		},
+#endif
+};
+#endif /* CONFIG_SYSCTL */
+
 /*
  * initialise the percpu counter for VM
  */
@@ -2185,6 +2236,9 @@ void __init mmap_init(void)
 
 	ret = percpu_counter_init(&vm_committed_as, 0, GFP_KERNEL);
 	VM_BUG_ON(ret);
+#ifdef CONFIG_SYSCTL
+	register_sysctl_init("vm", mmap_table);
+#endif
 }
 
 /*
-- 
2.34.1

[PATCH v3 -next 07/15] security: min_addr: move sysctl to security/min_addr.c

[Kaixiong Yu]

The dac_mmap_min_addr belongs to min_addr.c, move it to
min_addr.c from /kernel/sysctl.c. In the previous Linux kernel
boot process, sysctl_init_bases needs to be executed before
init_mmap_min_addr, So, register_sysctl_init should be executed
before update_mmap_min_addr in init_mmap_min_addr. And according
to the compilation condition in security/Makefile:

      obj-$(CONFIG_MMU)            += min_addr.o

if CONFIG_MMU is not defined, min_addr.c would not be included in the
compilation process. So, drop the CONFIG_MMU check.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com>
---
v3:
 - change the title
v2:
 - update the changelog to explain why drop CONFIG_MMU check.
---
 kernel/sysctl.c     |  9 ---------
 security/min_addr.c | 11 +++++++++++
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 41d4afc978e6..0c0bab3dad7d 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2059,15 +2059,6 @@ static struct ctl_table vm_table[] = {
 		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= SYSCTL_ZERO,
 	},
-#ifdef CONFIG_MMU
-	{
-		.procname	= "mmap_min_addr",
-		.data		= &dac_mmap_min_addr,
-		.maxlen		= sizeof(unsigned long),
-		.mode		= 0644,
-		.proc_handler	= mmap_min_addr_handler,
-	},
-#endif
 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
 	{
diff --git a/security/min_addr.c b/security/min_addr.c
index 0ce267c041ab..b2f61649e110 100644
--- a/security/min_addr.c
+++ b/security/min_addr.c
@@ -44,8 +44,19 @@ int mmap_min_addr_handler(const struct ctl_table *table, int write,
 	return ret;
 }
 
+static struct ctl_table min_addr_sysctl_table[] = {
+	{
+		.procname	= "mmap_min_addr",
+		.data		= &dac_mmap_min_addr,
+		.maxlen		= sizeof(unsigned long),
+		.mode		= 0644,
+		.proc_handler	= mmap_min_addr_handler,
+	},
+};
+
 static int __init init_mmap_min_addr(void)
 {
+	register_sysctl_init("vm", min_addr_sysctl_table);
 	update_mmap_min_addr();
 
 	return 0;
-- 
2.34.1

[PATCH v3 -next 08/15] mm: nommu: move sysctl to mm/nommu.c

[Kaixiong Yu]

The sysctl_nr_trim_pages belongs to nommu.c, move it to mm/nommu.c
from /kernel/sysctl.c. And remove the useless extern variable declaration
from include/linux/mm.h

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
---
v3:
 - change the title
v2:
 - fix the build error: expected ';' after top level declarator
 - fix the build error: call to undeclared function 'register_syscall_init',
   use 'register_sysctl_init' to replace it.
---
 include/linux/mm.h |  2 --
 kernel/sysctl.c    | 10 ----------
 mm/nommu.c         | 15 ++++++++++++++-
 3 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 50f0069280f4..c7f73bf32024 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -4070,8 +4070,6 @@ unsigned long wp_shared_mapping_range(struct address_space *mapping,
 				      pgoff_t first_index, pgoff_t nr);
 #endif
 
-extern int sysctl_nr_trim_pages;
-
 #ifdef CONFIG_PRINTK
 void mem_dump_obj(void *object);
 #else
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 0c0bab3dad7d..d3de31ec74bf 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2041,16 +2041,6 @@ static struct ctl_table vm_table[] = {
 		.extra1		= SYSCTL_ONE,
 		.extra2		= SYSCTL_FOUR,
 	},
-#ifndef CONFIG_MMU
-	{
-		.procname	= "nr_trim_pages",
-		.data		= &sysctl_nr_trim_pages,
-		.maxlen		= sizeof(sysctl_nr_trim_pages),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-	},
-#endif
 	{
 		.procname	= "vfs_cache_pressure",
 		.data		= &sysctl_vfs_cache_pressure,
diff --git a/mm/nommu.c b/mm/nommu.c
index 385b0c15add8..48b2812f492a 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -48,7 +48,6 @@ struct page *mem_map;
 unsigned long max_mapnr;
 EXPORT_SYMBOL(max_mapnr);
 unsigned long highest_memmap_pfn;
-int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS;
 int heap_stack_gap = 0;
 
 atomic_long_t mmap_pages_allocated;
@@ -392,6 +391,19 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 	return mm->brk = brk;
 }
 
+static int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS;
+
+static struct ctl_table nommu_table[] = {
+	{
+		.procname	= "nr_trim_pages",
+		.data		= &sysctl_nr_trim_pages,
+		.maxlen		= sizeof(sysctl_nr_trim_pages),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+	},
+};
+
 /*
  * initialise the percpu counter for VM and region record slabs
  */
@@ -402,6 +414,7 @@ void __init mmap_init(void)
 	ret = percpu_counter_init(&vm_committed_as, 0, GFP_KERNEL);
 	VM_BUG_ON(ret);
 	vm_region_jar = KMEM_CACHE(vm_region, SLAB_PANIC|SLAB_ACCOUNT);
+	register_sysctl_init("vm", nommu_table);
 }
 
 /*
-- 
2.34.1

[PATCH v3 -next 09/15] fs: fs-writeback: move sysctl to fs/fs-writeback.c

[Kaixiong Yu]

The dirtytime_expire_interval belongs to fs/fs-writeback.c, move it to
fs/fs-writeback.c from /kernel/sysctl.c. And remove the useless extern
variable declaration and the function declaration from
include/linux/writeback.h

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change dirtytime_expire_interval to static type
 - change the title
---
 fs/fs-writeback.c         | 30 +++++++++++++++++++++---------
 include/linux/writeback.h |  4 ----
 kernel/sysctl.c           |  8 --------
 3 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index d8bec3c1bb1f..4fedefdb8e15 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -65,7 +65,7 @@ struct wb_writeback_work {
  * timestamps written to disk after 12 hours, but in the worst case a
  * few inodes might not their timestamps updated for 24 hours.
  */
-unsigned int dirtytime_expire_interval = 12 * 60 * 60;
+static unsigned int dirtytime_expire_interval = 12 * 60 * 60;
 
 static inline struct inode *wb_inode(struct list_head *head)
 {
@@ -2413,14 +2413,7 @@ static void wakeup_dirtytime_writeback(struct work_struct *w)
 	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
 }
 
-static int __init start_dirtytime_writeback(void)
-{
-	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
-	return 0;
-}
-__initcall(start_dirtytime_writeback);
-
-int dirtytime_interval_handler(const struct ctl_table *table, int write,
+static int dirtytime_interval_handler(const struct ctl_table *table, int write,
 			       void *buffer, size_t *lenp, loff_t *ppos)
 {
 	int ret;
@@ -2431,6 +2424,25 @@ int dirtytime_interval_handler(const struct ctl_table *table, int write,
 	return ret;
 }
 
+static struct ctl_table vm_fs_writeback_table[] = {
+	{
+		.procname	= "dirtytime_expire_seconds",
+		.data		= &dirtytime_expire_interval,
+		.maxlen		= sizeof(dirtytime_expire_interval),
+		.mode		= 0644,
+		.proc_handler	= dirtytime_interval_handler,
+		.extra1		= SYSCTL_ZERO,
+	},
+};
+
+static int __init start_dirtytime_writeback(void)
+{
+	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
+	register_sysctl_init("vm", vm_fs_writeback_table);
+	return 0;
+}
+__initcall(start_dirtytime_writeback);
+
 /**
  * __mark_inode_dirty -	internal function to mark an inode dirty
  *
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index d6db822e4bb3..5f35b24aff7b 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -351,12 +351,8 @@ extern struct wb_domain global_wb_domain;
 /* These are exported to sysctl. */
 extern unsigned int dirty_writeback_interval;
 extern unsigned int dirty_expire_interval;
-extern unsigned int dirtytime_expire_interval;
 extern int laptop_mode;
 
-int dirtytime_interval_handler(const 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);
 unsigned long cgwb_calc_thresh(struct bdi_writeback *wb);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index d3de31ec74bf..373e018b950c 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2024,14 +2024,6 @@ static struct ctl_table kern_table[] = {
 };
 
 static struct ctl_table vm_table[] = {
-	{
-		.procname	= "dirtytime_expire_seconds",
-		.data		= &dirtytime_expire_interval,
-		.maxlen		= sizeof(dirtytime_expire_interval),
-		.mode		= 0644,
-		.proc_handler	= dirtytime_interval_handler,
-		.extra1		= SYSCTL_ZERO,
-	},
 	{
 		.procname	= "drop_caches",
 		.data		= &sysctl_drop_caches,
-- 
2.34.1

Re: [PATCH v3 -next 09/15] fs: fs-writeback: move sysctl to fs/fs-writeback.c

[Jan Kara]

On Thu 10-10-24 23:22:09, Kaixiong Yu wrote:
> The dirtytime_expire_interval belongs to fs/fs-writeback.c, move it to
> fs/fs-writeback.c from /kernel/sysctl.c. And remove the useless extern
> variable declaration and the function declaration from
> include/linux/writeback.h
> 
> Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
> Reviewed-by: Kees Cook <kees@kernel.org>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
> v3:
>  - change dirtytime_expire_interval to static type
>  - change the title
> ---
>  fs/fs-writeback.c         | 30 +++++++++++++++++++++---------
>  include/linux/writeback.h |  4 ----
>  kernel/sysctl.c           |  8 --------
>  3 files changed, 21 insertions(+), 21 deletions(-)
> 
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index d8bec3c1bb1f..4fedefdb8e15 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -65,7 +65,7 @@ struct wb_writeback_work {
>   * timestamps written to disk after 12 hours, but in the worst case a
>   * few inodes might not their timestamps updated for 24 hours.
>   */
> -unsigned int dirtytime_expire_interval = 12 * 60 * 60;
> +static unsigned int dirtytime_expire_interval = 12 * 60 * 60;
>  
>  static inline struct inode *wb_inode(struct list_head *head)
>  {
> @@ -2413,14 +2413,7 @@ static void wakeup_dirtytime_writeback(struct work_struct *w)
>  	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
>  }
>  
> -static int __init start_dirtytime_writeback(void)
> -{
> -	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
> -	return 0;
> -}
> -__initcall(start_dirtytime_writeback);
> -
> -int dirtytime_interval_handler(const struct ctl_table *table, int write,
> +static int dirtytime_interval_handler(const struct ctl_table *table, int write,
>  			       void *buffer, size_t *lenp, loff_t *ppos)
>  {
>  	int ret;
> @@ -2431,6 +2424,25 @@ int dirtytime_interval_handler(const struct ctl_table *table, int write,
>  	return ret;
>  }
>  
> +static struct ctl_table vm_fs_writeback_table[] = {
> +	{
> +		.procname	= "dirtytime_expire_seconds",
> +		.data		= &dirtytime_expire_interval,
> +		.maxlen		= sizeof(dirtytime_expire_interval),
> +		.mode		= 0644,
> +		.proc_handler	= dirtytime_interval_handler,
> +		.extra1		= SYSCTL_ZERO,
> +	},
> +};
> +
> +static int __init start_dirtytime_writeback(void)
> +{
> +	schedule_delayed_work(&dirtytime_work, dirtytime_expire_interval * HZ);
> +	register_sysctl_init("vm", vm_fs_writeback_table);
> +	return 0;
> +}
> +__initcall(start_dirtytime_writeback);
> +
>  /**
>   * __mark_inode_dirty -	internal function to mark an inode dirty
>   *
> diff --git a/include/linux/writeback.h b/include/linux/writeback.h
> index d6db822e4bb3..5f35b24aff7b 100644
> --- a/include/linux/writeback.h
> +++ b/include/linux/writeback.h
> @@ -351,12 +351,8 @@ extern struct wb_domain global_wb_domain;
>  /* These are exported to sysctl. */
>  extern unsigned int dirty_writeback_interval;
>  extern unsigned int dirty_expire_interval;
> -extern unsigned int dirtytime_expire_interval;
>  extern int laptop_mode;
>  
> -int dirtytime_interval_handler(const 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);
>  unsigned long cgwb_calc_thresh(struct bdi_writeback *wb);
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index d3de31ec74bf..373e018b950c 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -2024,14 +2024,6 @@ static struct ctl_table kern_table[] = {
>  };
>  
>  static struct ctl_table vm_table[] = {
> -	{
> -		.procname	= "dirtytime_expire_seconds",
> -		.data		= &dirtytime_expire_interval,
> -		.maxlen		= sizeof(dirtytime_expire_interval),
> -		.mode		= 0644,
> -		.proc_handler	= dirtytime_interval_handler,
> -		.extra1		= SYSCTL_ZERO,
> -	},
>  	{
>  		.procname	= "drop_caches",
>  		.data		= &sysctl_drop_caches,
> -- 
> 2.34.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

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

[Kaixiong Yu]

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@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
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

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

[Jan Kara]

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@huawei.com>
> Reviewed-by: Kees Cook <kees@kernel.org>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								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@suse.com>
SUSE Labs, CR

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

[Christian Brauner]

On Thu, Oct 10, 2024 at 11:22:10PM +0800, 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@huawei.com>
> Reviewed-by: Kees Cook <kees@kernel.org>
> ---

Reviewed-by: Christian Brauner <brauner@kernel.org>

[PATCH v3 -next 11/15] sunrpc: use vfs_pressure_ratio() helper

[Kaixiong Yu]

Use vfs_pressure_ratio() to simplify code.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
---
 net/sunrpc/auth.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 04534ea537c8..3d2b51d7e934 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -489,7 +489,7 @@ static unsigned long
 rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
 
 {
-	return number_cred_unused * sysctl_vfs_cache_pressure / 100;
+	return vfs_pressure_ratio(number_cred_unused);
 }
 
 static void
-- 
2.34.1

Re: [PATCH v3 -next 11/15] sunrpc: use vfs_pressure_ratio() helper

[Jeff Layton]

On Thu, 2024-10-10 at 23:22 +0800, Kaixiong Yu wrote:
> Use vfs_pressure_ratio() to simplify code.
> 
> Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
> Reviewed-by: Kees Cook <kees@kernel.org>
> Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
> ---
>  net/sunrpc/auth.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
> index 04534ea537c8..3d2b51d7e934 100644
> --- a/net/sunrpc/auth.c
> +++ b/net/sunrpc/auth.c
> @@ -489,7 +489,7 @@ static unsigned long
>  rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
>  
>  {
> -	return number_cred_unused * sysctl_vfs_cache_pressure / 100;
> +	return vfs_pressure_ratio(number_cred_unused);
>  }
>  
>  static void

Acked-by: Jeff Layton <jlayton@kernel.org>

Re: [PATCH v3 -next 11/15] sunrpc: use vfs_pressure_ratio() helper

[NeilBrown]

On Fri, 11 Oct 2024, Jeff Layton wrote:
> On Thu, 2024-10-10 at 23:22 +0800, Kaixiong Yu wrote:
> > Use vfs_pressure_ratio() to simplify code.
> > 
> > Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
> > Reviewed-by: Kees Cook <kees@kernel.org>
> > Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
> > ---
> >  net/sunrpc/auth.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
> > index 04534ea537c8..3d2b51d7e934 100644
> > --- a/net/sunrpc/auth.c
> > +++ b/net/sunrpc/auth.c
> > @@ -489,7 +489,7 @@ static unsigned long
> >  rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
> >  
> >  {
> > -	return number_cred_unused * sysctl_vfs_cache_pressure / 100;
> > +	return vfs_pressure_ratio(number_cred_unused);
> >  }
> >  
> >  static void
> 
> Acked-by: Jeff Layton <jlayton@kernel.org>
> 

I realise this is a bit of a tangent, and I'm not objecting to this
patch, but I wonder what the justification is for using
vfs_cache_pressure here.  The sysctl is documented as

   This percentage value controls the tendency of the kernel to reclaim
   the memory which is used for caching of directory and inode objects.

So it can sensibly be used for dentries and inode, and for anything
directly related like the nfs access cache (which is attached to inodes)
and the nfs xattr cache.

But the sunrpc cred cache scales with the number of active users, not
the number of inodes/dentries.

So I think this should simply "return number_cred_unused;".

What do others think?

NeilBrown

Re: [PATCH v3 -next 11/15] sunrpc: use vfs_pressure_ratio() helper

[Jeff Layton]

On Fri, 2024-10-11 at 08:43 +1100, NeilBrown wrote:
> On Fri, 11 Oct 2024, Jeff Layton wrote:
> > On Thu, 2024-10-10 at 23:22 +0800, Kaixiong Yu wrote:
> > > Use vfs_pressure_ratio() to simplify code.
> > > 
> > > Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
> > > Reviewed-by: Kees Cook <kees@kernel.org>
> > > Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
> > > ---
> > >  net/sunrpc/auth.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
> > > index 04534ea537c8..3d2b51d7e934 100644
> > > --- a/net/sunrpc/auth.c
> > > +++ b/net/sunrpc/auth.c
> > > @@ -489,7 +489,7 @@ static unsigned long
> > >  rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
> > >  
> > >  {
> > > -	return number_cred_unused * sysctl_vfs_cache_pressure / 100;
> > > +	return vfs_pressure_ratio(number_cred_unused);
> > >  }
> > >  
> > >  static void
> > 
> > Acked-by: Jeff Layton <jlayton@kernel.org>
> > 
> 
> I realise this is a bit of a tangent, and I'm not objecting to this
> patch, but I wonder what the justification is for using
> vfs_cache_pressure here.  The sysctl is documented as
> 
>    This percentage value controls the tendency of the kernel to reclaim
>    the memory which is used for caching of directory and inode objects.
> 
> So it can sensibly be used for dentries and inode, and for anything
> directly related like the nfs access cache (which is attached to inodes)
> and the nfs xattr cache.
> 
> But the sunrpc cred cache scales with the number of active users, not
> the number of inodes/dentries.
> 
> So I think this should simply "return number_cred_unused;".
> 
> What do others think?
> 
> NeilBrown
> 

-----------------8<------------------
 * @count_objects should return the number of freeable items in the cache. If
 * there are no objects to free, it should return SHRINK_EMPTY, while 0 is
 * returned in cases of the number of freeable items cannot be determined
 * or shrinker should skip this cache for this time (e.g., their number
 * is below shrinkable limit)...
-----------------8<------------------

number_cred_unused does sound like a better way to report this.

-- 
Jeff Layton <jlayton@kernel.org>

Re: [PATCH v3 -next 11/15] sunrpc: use vfs_pressure_ratio() helper

[yukaixiong]

On 2024/10/11 20:38, Jeff Layton wrote:
> On Fri, 2024-10-11 at 08:43 +1100, NeilBrown wrote:
>> On Fri, 11 Oct 2024, Jeff Layton wrote:
>>> On Thu, 2024-10-10 at 23:22 +0800, Kaixiong Yu wrote:
>>>> Use vfs_pressure_ratio() to simplify code.
>>>>
>>>> Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
>>>> Reviewed-by: Kees Cook <kees@kernel.org>
>>>> Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
>>>> ---
>>>>   net/sunrpc/auth.c | 2 +-
>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
>>>> index 04534ea537c8..3d2b51d7e934 100644
>>>> --- a/net/sunrpc/auth.c
>>>> +++ b/net/sunrpc/auth.c
>>>> @@ -489,7 +489,7 @@ static unsigned long
>>>>   rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
>>>>   
>>>>   {
>>>> -	return number_cred_unused * sysctl_vfs_cache_pressure / 100;
>>>> +	return vfs_pressure_ratio(number_cred_unused);
>>>>   }
>>>>   
>>>>   static void
>>> Acked-by: Jeff Layton <jlayton@kernel.org>
>>>
>> I realise this is a bit of a tangent, and I'm not objecting to this
>> patch, but I wonder what the justification is for using
>> vfs_cache_pressure here.  The sysctl is documented as
>>
>>     This percentage value controls the tendency of the kernel to reclaim
>>     the memory which is used for caching of directory and inode objects.
>>
>> So it can sensibly be used for dentries and inode, and for anything
>> directly related like the nfs access cache (which is attached to inodes)
>> and the nfs xattr cache.
>>
>> But the sunrpc cred cache scales with the number of active users, not
>> the number of inodes/dentries.
>>
>> So I think this should simply "return number_cred_unused;".
>>
>> What do others think?
>>
>> NeilBrown
>>
> -----------------8<------------------
>   * @count_objects should return the number of freeable items in the cache. If
>   * there are no objects to free, it should return SHRINK_EMPTY, while 0 is
>   * returned in cases of the number of freeable items cannot be determined
>   * or shrinker should skip this cache for this time (e.g., their number
>   * is below shrinkable limit)...
> -----------------8<------------------
>
> number_cred_unused does sound like a better way to report this.
Thanks, I'll take NeilBrown's advice.

Re: [PATCH v3 -next 11/15] sunrpc: use vfs_pressure_ratio() helper

[yukaixiong]

On 2024/10/11 5:43, NeilBrown wrote:
> On Fri, 11 Oct 2024, Jeff Layton wrote:
>> On Thu, 2024-10-10 at 23:22 +0800, Kaixiong Yu wrote:
>>> Use vfs_pressure_ratio() to simplify code.
>>>
>>> Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
>>> Reviewed-by: Kees Cook <kees@kernel.org>
>>> Acked-by: Anna Schumaker <anna.schumaker@oracle.com>
>>> ---
>>>   net/sunrpc/auth.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
>>> index 04534ea537c8..3d2b51d7e934 100644
>>> --- a/net/sunrpc/auth.c
>>> +++ b/net/sunrpc/auth.c
>>> @@ -489,7 +489,7 @@ static unsigned long
>>>   rpcauth_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
>>>   
>>>   {
>>> -	return number_cred_unused * sysctl_vfs_cache_pressure / 100;
>>> +	return vfs_pressure_ratio(number_cred_unused);
>>>   }
>>>   
>>>   static void
>> Acked-by: Jeff Layton <jlayton@kernel.org>
>>
> I realise this is a bit of a tangent, and I'm not objecting to this
> patch, but I wonder what the justification is for using
> vfs_cache_pressure here.  The sysctl is documented as
>
>     This percentage value controls the tendency of the kernel to reclaim
>     the memory which is used for caching of directory and inode objects.
>
> So it can sensibly be used for dentries and inode, and for anything
> directly related like the nfs access cache (which is attached to inodes)
> and the nfs xattr cache.
>
> But the sunrpc cred cache scales with the number of active users, not
> the number of inodes/dentries.
>
> So I think this should simply "return number_cred_unused;".
>
> What do others think?
>
> NeilBrown
>
> .

Thank you, I will receive your advice.

[PATCH v3 -next 12/15] fs: dcache: move the sysctl to fs/dcache.c

[Kaixiong Yu]

The sysctl_vfs_cache_pressure belongs to fs/dcache.c, move it to
fs/dcache.c from kernel/sysctl.c. As a part of fs/dcache.c cleaning,
sysctl_vfs_cache_pressure is changed to a static variable, and change
the inline-type function vfs_pressure_ratio() to out-of-inline type,
export vfs_pressure_ratio() with EXPORT_SYMBOL_GPL to be used by other
files. Move the unneeded include(linux/dcache.h).

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christian Brauner <brauner@kernel.org>
---
v3；
 - change the title
v2:
 - update the changelog to call out changing the inline-type function
   vfs_pressure_ratio() to out-of-inline type
---
 fs/dcache.c            | 21 +++++++++++++++++++--
 include/linux/dcache.h |  7 +------
 kernel/sysctl.c        |  9 ---------
 3 files changed, 20 insertions(+), 17 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index b4d5e9e1e43d..de240b7f6c47 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -73,8 +73,13 @@
  * If no ancestor relationship:
  * arbitrary, since it's serialized on rename_lock
  */
-int sysctl_vfs_cache_pressure __read_mostly = 100;
-EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure);
+static int sysctl_vfs_cache_pressure __read_mostly = 100;
+
+unsigned long vfs_pressure_ratio(unsigned long val)
+{
+	return mult_frac(val, sysctl_vfs_cache_pressure, 100);
+}
+EXPORT_SYMBOL_GPL(vfs_pressure_ratio);
 
 __cacheline_aligned_in_smp DEFINE_SEQLOCK(rename_lock);
 
@@ -211,8 +216,20 @@ static struct ctl_table fs_dcache_sysctls[] = {
 	},
 };
 
+static struct ctl_table vm_dcache_sysctls[] = {
+	{
+		.procname	= "vfs_cache_pressure",
+		.data		= &sysctl_vfs_cache_pressure,
+		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+	},
+};
+
 static int __init init_fs_dcache_sysctls(void)
 {
+	register_sysctl_init("vm", vm_dcache_sysctls);
 	register_sysctl_init("fs", fs_dcache_sysctls);
 	return 0;
 }
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index bff956f7b2b9..c81c2e9e13df 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -508,12 +508,7 @@ static inline int simple_positive(const struct dentry *dentry)
 	return d_really_is_positive(dentry) && !d_unhashed(dentry);
 }
 
-extern int sysctl_vfs_cache_pressure;
-
-static inline unsigned long vfs_pressure_ratio(unsigned long val)
-{
-	return mult_frac(val, sysctl_vfs_cache_pressure, 100);
-}
+unsigned long vfs_pressure_ratio(unsigned long val);
 
 /**
  * d_inode - Get the actual inode of this dentry
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index d638a1bac9af..6f03fc749794 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -46,7 +46,6 @@
 #include <linux/key.h>
 #include <linux/times.h>
 #include <linux/limits.h>
-#include <linux/dcache.h>
 #include <linux/syscalls.h>
 #include <linux/nfs_fs.h>
 #include <linux/acpi.h>
@@ -2024,14 +2023,6 @@ static struct ctl_table kern_table[] = {
 };
 
 static struct ctl_table vm_table[] = {
-	{
-		.procname	= "vfs_cache_pressure",
-		.data		= &sysctl_vfs_cache_pressure,
-		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-	},
 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
 	{
-- 
2.34.1

[PATCH v3 -next 13/15] x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c

[Kaixiong Yu]

When CONFIG_X86_32 is defined and CONFIG_UML is not defined,
vdso_enabled belongs to arch/x86/entry/vdso/vdso32-setup.c.
So, move it into its own file.

Before this patch, vdso_enabled was allowed to be set to
a value exceeding 1 on x86_32 architecture. After this patch is
applied, vdso_enabled is not permitted to set the value more than 1.
It does not matter, because according to the function load_vdso32(),
only vdso_enabled is set to 1, VDSO would be enabled. Other values
all mean "disabled". The same limitation could be seen in the
function vdso32_setup().

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
 arch/x86/entry/vdso/vdso32-setup.c | 16 +++++++++++-----
 kernel/sysctl.c                    |  8 +-------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/x86/entry/vdso/vdso32-setup.c b/arch/x86/entry/vdso/vdso32-setup.c
index 76e4e74f35b5..5a6886a006ab 100644
--- a/arch/x86/entry/vdso/vdso32-setup.c
+++ b/arch/x86/entry/vdso/vdso32-setup.c
@@ -51,15 +51,17 @@ __setup("vdso32=", vdso32_setup);
 __setup_param("vdso=", vdso_setup, vdso32_setup, 0);
 #endif
 
-#ifdef CONFIG_X86_64
 
 #ifdef CONFIG_SYSCTL
-/* Register vsyscall32 into the ABI table */
 #include <linux/sysctl.h>
 
-static struct ctl_table abi_table2[] = {
+static struct ctl_table vdso_table[] = {
 	{
+#ifdef CONFIG_X86_64
 		.procname	= "vsyscall32",
+#elif (defined(CONFIG_X86_32) && !defined(CONFIG_UML))
+		.procname	= "vdso_enabled",
+#endif
 		.data		= &vdso32_enabled,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
@@ -71,10 +73,14 @@ static struct ctl_table abi_table2[] = {
 
 static __init int ia32_binfmt_init(void)
 {
-	register_sysctl("abi", abi_table2);
+#ifdef CONFIG_X86_64
+	/* Register vsyscall32 into the ABI table */
+	register_sysctl("abi", vdso_table);
+#elif (defined(CONFIG_X86_32) && !defined(CONFIG_UML))
+	register_sysctl_init("vm", vdso_table);
+#endif
 	return 0;
 }
 __initcall(ia32_binfmt_init);
 #endif /* CONFIG_SYSCTL */
 
-#endif	/* CONFIG_X86_64 */
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 6f03fc749794..24617be93119 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2023,17 +2023,11 @@ static struct ctl_table kern_table[] = {
 };
 
 static struct ctl_table vm_table[] = {
-#if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
-   (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
+#if defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)
 	{
 		.procname	= "vdso_enabled",
-#ifdef CONFIG_X86_32
-		.data		= &vdso32_enabled,
-		.maxlen		= sizeof(vdso32_enabled),
-#else
 		.data		= &vdso_enabled,
 		.maxlen		= sizeof(vdso_enabled),
-#endif
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 		.extra1		= SYSCTL_ZERO,
-- 
2.34.1

[PATCH v3 -next 14/15] sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c

[Kaixiong Yu]

When CONFIG_SUPERH and CONFIG_VSYSCALL are defined,
vdso_enabled belongs to arch/sh/kernel/vsyscall/vsyscall.c.
So, move it into its own file. After this patch is applied,
all sysctls of vm_table would be moved. So, delete vm_table.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
v3:
 - change the title
---
 arch/sh/kernel/vsyscall/vsyscall.c | 14 ++++++++++++++
 kernel/sysctl.c                    | 14 --------------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/sh/kernel/vsyscall/vsyscall.c b/arch/sh/kernel/vsyscall/vsyscall.c
index add35c51e017..43bc3715e38c 100644
--- a/arch/sh/kernel/vsyscall/vsyscall.c
+++ b/arch/sh/kernel/vsyscall/vsyscall.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/elf.h>
 #include <linux/sched.h>
+#include <linux/sysctl.h>
 #include <linux/err.h>
 
 /*
@@ -30,6 +31,17 @@ static int __init vdso_setup(char *s)
 }
 __setup("vdso=", vdso_setup);
 
+static struct ctl_table vdso_table[] = {
+	{
+		.procname	= "vdso_enabled",
+		.data		= &vdso_enabled,
+		.maxlen		= sizeof(vdso_enabled),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= SYSCTL_ZERO,
+	},
+};
+
 /*
  * These symbols are defined by vsyscall.o to mark the bounds
  * of the ELF DSO images included therein.
@@ -55,6 +67,8 @@ int __init vsyscall_init(void)
 	       &vsyscall_trapa_start,
 	       &vsyscall_trapa_end - &vsyscall_trapa_start);
 
+	register_sysctl_init("vm", vdso_table);
+
 	return 0;
 }
 
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 24617be93119..f04da9f3abc6 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -2022,23 +2022,9 @@ static struct ctl_table kern_table[] = {
 #endif
 };
 
-static struct ctl_table vm_table[] = {
-#if defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)
-	{
-		.procname	= "vdso_enabled",
-		.data		= &vdso_enabled,
-		.maxlen		= sizeof(vdso_enabled),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-		.extra1		= SYSCTL_ZERO,
-	},
-#endif
-};
-
 int __init sysctl_init_bases(void)
 {
 	register_sysctl_init("kernel", kern_table);
-	register_sysctl_init("vm", vm_table);
 
 	return 0;
 }
-- 
2.34.1

[PATCH v3 -next 15/15] sysctl: remove unneeded include

[Kaixiong Yu]

Removing unneeded mm includes in kernel/sysctl.c.

Signed-off-by: Kaixiong Yu <yukaixiong@huawei.com>
Reviewed-by: Kees Cook <kees@kernel.org>
---
 kernel/sysctl.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index f04da9f3abc6..6e3e0ce4da79 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -20,8 +20,6 @@
  */
 
 #include <linux/module.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
 #include <linux/sysctl.h>
 #include <linux/bitmap.h>
 #include <linux/signal.h>
@@ -30,7 +28,6 @@
 #include <linux/proc_fs.h>
 #include <linux/security.h>
 #include <linux/ctype.h>
-#include <linux/kmemleak.h>
 #include <linux/filter.h>
 #include <linux/fs.h>
 #include <linux/init.h>
@@ -41,7 +38,6 @@
 #include <linux/highuid.h>
 #include <linux/writeback.h>
 #include <linux/ratelimit.h>
-#include <linux/hugetlb.h>
 #include <linux/initrd.h>
 #include <linux/key.h>
 #include <linux/times.h>
@@ -52,13 +48,11 @@
 #include <linux/reboot.h>
 #include <linux/ftrace.h>
 #include <linux/perf_event.h>
-#include <linux/oom.h>
 #include <linux/kmod.h>
 #include <linux/capability.h>
 #include <linux/binfmts.h>
 #include <linux/sched/sysctl.h>
 #include <linux/mount.h>
-#include <linux/userfaultfd_k.h>
 #include <linux/pid.h>
 
 #include "../lib/kstrtox.h"
-- 
2.34.1

Re: [PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[Liam R. Howlett]

* Kaixiong Yu <yukaixiong@huawei.com> [241010 10:11]:
> This patch series moves sysctls of vm_table in kernel/sysctl.c to
> places where they actually belong, and do some related code clean-ups.
> After this patch series, all sysctls in vm_table have been moved into its
> own files, meanwhile, delete vm_table.
> 
> All the modifications of this patch series base on
> linux-next(tags/next-20241010). To test this patch series, the code was
> compiled with both the CONFIG_SYSCTL enabled and disabled on arm64 and
> x86_64 architectures. After this patch series is applied, all files
> under /proc/sys/vm can be read or written normally.

This change set moves nommu code out of the common code into the nommu.c
file (which is nice), but the above text implies that no testing was
performed on that code.  Could we have some basic compile/boot testing
for nommu?

> 
> Changes in v3:
>  - change patch1~10, patch14 title suggested by Joel Granados
>  - change sysctl_stat_interval to static type in patch1
>  - add acked-by from Paul Moore in patch7
>  - change dirtytime_expire_interval to static type in patch9
>  - add acked-by from Anna Schumaker in patch11
> 
> Changes in v2:
>  - fix sysctl_max_map_count undeclared issue in mm/nommu.c for patch6
>  - update changelog for patch7/12, suggested by Kees/Paul
>  - fix patch8, sorry for wrong changes and forget to built with NOMMU
>  - add reviewed-by from Kees except patch8 since patch8 is wrong in v1
>  - add reviewed-by from Jan Kara, Christian Brauner in patch12
> 
> Kaixiong Yu (15):
>   mm: vmstat: move sysctls to mm/vmstat.c
>   mm: filemap: move sysctl to mm/filemap.c
>   mm: swap: move sysctl to mm/swap.c
>   mm: vmscan: move vmscan sysctls to mm/vmscan.c
>   mm: util: move sysctls to mm/util.c
>   mm: mmap: move sysctl to mm/mmap.c
>   security: min_addr: move sysctl to security/min_addr.c
>   mm: nommu: move sysctl to mm/nommu.c
>   fs: fs-writeback: move sysctl to fs/fs-writeback.c
>   fs: drop_caches: move sysctl to fs/drop_caches.c
>   sunrpc: use vfs_pressure_ratio() helper
>   fs: dcache: move the sysctl to fs/dcache.c
>   x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c
>   sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c
>   sysctl: remove unneeded include
> 
>  arch/sh/kernel/vsyscall/vsyscall.c |  14 ++
>  arch/x86/entry/vdso/vdso32-setup.c |  16 ++-
>  fs/dcache.c                        |  21 ++-
>  fs/drop_caches.c                   |  23 ++-
>  fs/fs-writeback.c                  |  30 ++--
>  include/linux/dcache.h             |   7 +-
>  include/linux/mm.h                 |  23 ---
>  include/linux/mman.h               |   2 -
>  include/linux/swap.h               |   9 --
>  include/linux/vmstat.h             |  11 --
>  include/linux/writeback.h          |   4 -
>  kernel/sysctl.c                    | 221 -----------------------------
>  mm/filemap.c                       |  18 ++-
>  mm/internal.h                      |  10 ++
>  mm/mmap.c                          |  54 +++++++
>  mm/nommu.c                         |  15 +-
>  mm/swap.c                          |  16 ++-
>  mm/swap.h                          |   1 +
>  mm/util.c                          |  67 +++++++--
>  mm/vmscan.c                        |  23 +++
>  mm/vmstat.c                        |  44 +++++-
>  net/sunrpc/auth.c                  |   2 +-
>  security/min_addr.c                |  11 ++
>  23 files changed, 330 insertions(+), 312 deletions(-)
> 
> -- 
> 2.34.1
> 

Re: [PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[yukaixiong]

On 2024/10/11 21:04, Liam R. Howlett wrote:
> * Kaixiong Yu <yukaixiong@huawei.com> [241010 10:11]:
>> This patch series moves sysctls of vm_table in kernel/sysctl.c to
>> places where they actually belong, and do some related code clean-ups.
>> After this patch series, all sysctls in vm_table have been moved into its
>> own files, meanwhile, delete vm_table.
>>
>> All the modifications of this patch series base on
>> linux-next(tags/next-20241010). To test this patch series, the code was
>> compiled with both the CONFIG_SYSCTL enabled and disabled on arm64 and
>> x86_64 architectures. After this patch series is applied, all files
>> under /proc/sys/vm can be read or written normally.
> This change set moves nommu code out of the common code into the nommu.c
> file (which is nice), but the above text implies that no testing was
> performed on that code.  Could we have some basic compile/boot testing
> for nommu?
this patch series has been compiled with CONFIG_MMU=n on arm，and produce
nommu.o without error and warning. But I don't have machine to do test 
for nommu.
>> Changes in v3:
>>   - change patch1~10, patch14 title suggested by Joel Granados
>>   - change sysctl_stat_interval to static type in patch1
>>   - add acked-by from Paul Moore in patch7
>>   - change dirtytime_expire_interval to static type in patch9
>>   - add acked-by from Anna Schumaker in patch11
>>
>> Changes in v2:
>>   - fix sysctl_max_map_count undeclared issue in mm/nommu.c for patch6
>>   - update changelog for patch7/12, suggested by Kees/Paul
>>   - fix patch8, sorry for wrong changes and forget to built with NOMMU
>>   - add reviewed-by from Kees except patch8 since patch8 is wrong in v1
>>   - add reviewed-by from Jan Kara, Christian Brauner in patch12
>>
>> Kaixiong Yu (15):
>>    mm: vmstat: move sysctls to mm/vmstat.c
>>    mm: filemap: move sysctl to mm/filemap.c
>>    mm: swap: move sysctl to mm/swap.c
>>    mm: vmscan: move vmscan sysctls to mm/vmscan.c
>>    mm: util: move sysctls to mm/util.c
>>    mm: mmap: move sysctl to mm/mmap.c
>>    security: min_addr: move sysctl to security/min_addr.c
>>    mm: nommu: move sysctl to mm/nommu.c
>>    fs: fs-writeback: move sysctl to fs/fs-writeback.c
>>    fs: drop_caches: move sysctl to fs/drop_caches.c
>>    sunrpc: use vfs_pressure_ratio() helper
>>    fs: dcache: move the sysctl to fs/dcache.c
>>    x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c
>>    sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c
>>    sysctl: remove unneeded include
>>
>>   arch/sh/kernel/vsyscall/vsyscall.c |  14 ++
>>   arch/x86/entry/vdso/vdso32-setup.c |  16 ++-
>>   fs/dcache.c                        |  21 ++-
>>   fs/drop_caches.c                   |  23 ++-
>>   fs/fs-writeback.c                  |  30 ++--
>>   include/linux/dcache.h             |   7 +-
>>   include/linux/mm.h                 |  23 ---
>>   include/linux/mman.h               |   2 -
>>   include/linux/swap.h               |   9 --
>>   include/linux/vmstat.h             |  11 --
>>   include/linux/writeback.h          |   4 -
>>   kernel/sysctl.c                    | 221 -----------------------------
>>   mm/filemap.c                       |  18 ++-
>>   mm/internal.h                      |  10 ++
>>   mm/mmap.c                          |  54 +++++++
>>   mm/nommu.c                         |  15 +-
>>   mm/swap.c                          |  16 ++-
>>   mm/swap.h                          |   1 +
>>   mm/util.c                          |  67 +++++++--
>>   mm/vmscan.c                        |  23 +++
>>   mm/vmstat.c                        |  44 +++++-
>>   net/sunrpc/auth.c                  |   2 +-
>>   security/min_addr.c                |  11 ++
>>   23 files changed, 330 insertions(+), 312 deletions(-)
>>
>> -- 
>> 2.34.1
>>
> .
>

Re: [PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[Joel Granados]

On Thu, Oct 10, 2024 at 11:22:00PM +0800, Kaixiong Yu wrote:
> This patch series moves sysctls of vm_table in kernel/sysctl.c to
> places where they actually belong, and do some related code clean-ups.
> After this patch series, all sysctls in vm_table have been moved into its
> own files, meanwhile, delete vm_table.
> 
> All the modifications of this patch series base on
> linux-next(tags/next-20241010). To test this patch series, the code was
> compiled with both the CONFIG_SYSCTL enabled and disabled on arm64 and
> x86_64 architectures. After this patch series is applied, all files
> under /proc/sys/vm can be read or written normally.
> 
> Changes in v3:
>  - change patch1~10, patch14 title suggested by Joel Granados
>  - change sysctl_stat_interval to static type in patch1
>  - add acked-by from Paul Moore in patch7
>  - change dirtytime_expire_interval to static type in patch9
>  - add acked-by from Anna Schumaker in patch11
> 
> Changes in v2:
>  - fix sysctl_max_map_count undeclared issue in mm/nommu.c for patch6
>  - update changelog for patch7/12, suggested by Kees/Paul
>  - fix patch8, sorry for wrong changes and forget to built with NOMMU
>  - add reviewed-by from Kees except patch8 since patch8 is wrong in v1
>  - add reviewed-by from Jan Kara, Christian Brauner in patch12
> 
> Kaixiong Yu (15):
>   mm: vmstat: move sysctls to mm/vmstat.c
>   mm: filemap: move sysctl to mm/filemap.c
>   mm: swap: move sysctl to mm/swap.c
>   mm: vmscan: move vmscan sysctls to mm/vmscan.c
>   mm: util: move sysctls to mm/util.c
>   mm: mmap: move sysctl to mm/mmap.c
>   security: min_addr: move sysctl to security/min_addr.c
>   mm: nommu: move sysctl to mm/nommu.c
>   fs: fs-writeback: move sysctl to fs/fs-writeback.c
>   fs: drop_caches: move sysctl to fs/drop_caches.c
>   sunrpc: use vfs_pressure_ratio() helper
>   fs: dcache: move the sysctl to fs/dcache.c
>   x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c
>   sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c
>   sysctl: remove unneeded include
> 
>  arch/sh/kernel/vsyscall/vsyscall.c |  14 ++
>  arch/x86/entry/vdso/vdso32-setup.c |  16 ++-
>  fs/dcache.c                        |  21 ++-
>  fs/drop_caches.c                   |  23 ++-
>  fs/fs-writeback.c                  |  30 ++--
>  include/linux/dcache.h             |   7 +-
>  include/linux/mm.h                 |  23 ---
>  include/linux/mman.h               |   2 -
>  include/linux/swap.h               |   9 --
>  include/linux/vmstat.h             |  11 --
>  include/linux/writeback.h          |   4 -
>  kernel/sysctl.c                    | 221 -----------------------------
>  mm/filemap.c                       |  18 ++-
>  mm/internal.h                      |  10 ++
>  mm/mmap.c                          |  54 +++++++
>  mm/nommu.c                         |  15 +-
>  mm/swap.c                          |  16 ++-
>  mm/swap.h                          |   1 +
>  mm/util.c                          |  67 +++++++--
>  mm/vmscan.c                        |  23 +++
>  mm/vmstat.c                        |  44 +++++-
>  net/sunrpc/auth.c                  |   2 +-
>  security/min_addr.c                |  11 ++
>  23 files changed, 330 insertions(+), 312 deletions(-)
> 
> -- 
> 2.34.1
> 
General comment for the patchset in general. I would consider making the
new sysctl tables const. There is an effort for doing this and it has
already lanted in linux-next. So if you base your patch from a recent
next release, then it should just work. If you *do* decide to add a
const qualifier, then note that you will create a dependency with the
sysctl patchset currently in next and that will have to go in before.

Best

-- 

Joel Granados

Re: [PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[yukaixiong]

On 2024/10/21 15:22, Joel Granados wrote:
> On Thu, Oct 10, 2024 at 11:22:00PM +0800, Kaixiong Yu wrote:
>> This patch series moves sysctls of vm_table in kernel/sysctl.c to
>> places where they actually belong, and do some related code clean-ups.
>> After this patch series, all sysctls in vm_table have been moved into its
>> own files, meanwhile, delete vm_table.
>>
>> All the modifications of this patch series base on
>> linux-next(tags/next-20241010). To test this patch series, the code was
>> compiled with both the CONFIG_SYSCTL enabled and disabled on arm64 and
>> x86_64 architectures. After this patch series is applied, all files
>> under /proc/sys/vm can be read or written normally.
>>
>> Changes in v3:
>>   - change patch1~10, patch14 title suggested by Joel Granados
>>   - change sysctl_stat_interval to static type in patch1
>>   - add acked-by from Paul Moore in patch7
>>   - change dirtytime_expire_interval to static type in patch9
>>   - add acked-by from Anna Schumaker in patch11
>>
>> Changes in v2:
>>   - fix sysctl_max_map_count undeclared issue in mm/nommu.c for patch6
>>   - update changelog for patch7/12, suggested by Kees/Paul
>>   - fix patch8, sorry for wrong changes and forget to built with NOMMU
>>   - add reviewed-by from Kees except patch8 since patch8 is wrong in v1
>>   - add reviewed-by from Jan Kara, Christian Brauner in patch12
>>
>> Kaixiong Yu (15):
>>    mm: vmstat: move sysctls to mm/vmstat.c
>>    mm: filemap: move sysctl to mm/filemap.c
>>    mm: swap: move sysctl to mm/swap.c
>>    mm: vmscan: move vmscan sysctls to mm/vmscan.c
>>    mm: util: move sysctls to mm/util.c
>>    mm: mmap: move sysctl to mm/mmap.c
>>    security: min_addr: move sysctl to security/min_addr.c
>>    mm: nommu: move sysctl to mm/nommu.c
>>    fs: fs-writeback: move sysctl to fs/fs-writeback.c
>>    fs: drop_caches: move sysctl to fs/drop_caches.c
>>    sunrpc: use vfs_pressure_ratio() helper
>>    fs: dcache: move the sysctl to fs/dcache.c
>>    x86: vdso: move the sysctl to arch/x86/entry/vdso/vdso32-setup.c
>>    sh: vdso: move the sysctl to arch/sh/kernel/vsyscall/vsyscall.c
>>    sysctl: remove unneeded include
>>
>>   arch/sh/kernel/vsyscall/vsyscall.c |  14 ++
>>   arch/x86/entry/vdso/vdso32-setup.c |  16 ++-
>>   fs/dcache.c                        |  21 ++-
>>   fs/drop_caches.c                   |  23 ++-
>>   fs/fs-writeback.c                  |  30 ++--
>>   include/linux/dcache.h             |   7 +-
>>   include/linux/mm.h                 |  23 ---
>>   include/linux/mman.h               |   2 -
>>   include/linux/swap.h               |   9 --
>>   include/linux/vmstat.h             |  11 --
>>   include/linux/writeback.h          |   4 -
>>   kernel/sysctl.c                    | 221 -----------------------------
>>   mm/filemap.c                       |  18 ++-
>>   mm/internal.h                      |  10 ++
>>   mm/mmap.c                          |  54 +++++++
>>   mm/nommu.c                         |  15 +-
>>   mm/swap.c                          |  16 ++-
>>   mm/swap.h                          |   1 +
>>   mm/util.c                          |  67 +++++++--
>>   mm/vmscan.c                        |  23 +++
>>   mm/vmstat.c                        |  44 +++++-
>>   net/sunrpc/auth.c                  |   2 +-
>>   security/min_addr.c                |  11 ++
>>   23 files changed, 330 insertions(+), 312 deletions(-)
>>
>> -- 
>> 2.34.1
>>
> General comment for the patchset in general. I would consider making the
> new sysctl tables const. There is an effort for doing this and it has
> already lanted in linux-next. So if you base your patch from a recent
> next release, then it should just work. If you *do* decide to add a
> const qualifier, then note that you will create a dependency with the
> sysctl patchset currently in next and that will have to go in before.
>
> Best
>

Sorry,  I don't understand what is the meaning of "create a dependency 
with the sysctl patchset".

Do you just want me to change all "static struct ctl_table" type table 
into "static const struct ctl_table" type in my patchset?

Re: [PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[Joel Granados]

On Thu, Oct 24, 2024 at 04:07:10PM +0800, yukaixiong wrote:
...
> 
> 
> >>   mm/swap.c                          |  16 ++-
> >>   mm/swap.h                          |   1 +
> >>   mm/util.c                          |  67 +++++++--
> >>   mm/vmscan.c                        |  23 +++
> >>   mm/vmstat.c                        |  44 +++++-
> >>   net/sunrpc/auth.c                  |   2 +-
> >>   security/min_addr.c                |  11 ++
> >>   23 files changed, 330 insertions(+), 312 deletions(-)
> >>
> >> -- 
> >> 2.34.1
> >>
> > General comment for the patchset in general. I would consider making the
> > new sysctl tables const. There is an effort for doing this and it has
> > already lanted in linux-next. So if you base your patch from a recent
> > next release, then it should just work. If you *do* decide to add a
> > const qualifier, then note that you will create a dependency with the
> > sysctl patchset currently in next and that will have to go in before.
> >
> > Best
> >
> 
> Sorry,  I don't understand what is the meaning of "create a dependency 
> with the sysctl patchset".
The patches in the sysctl subsys that allow you to qualify the ctl_table
as const are not in mainline yet. They are in linux-next. This means
that if these patches go into the next kernel release before the
sysctl-next branch, it will have compilation errors. Therefore the
sysctl-next branch needs to be pulled in to the new kernel release
before this patchest. This also means that for this to build properly it
has to be based on a linux-next release.

> 
> Do you just want me to change all "static struct ctl_table" type table 
> into "static const struct ctl_table" type in my patchset?
You should const qualify them if the maintainer that is pulling in these
patches is ok with it. You should *not* const qualify them if the
maintainer prefers otherwise.

Please get back to me if I did not address your questions.

Best

-- 

Joel Granados

Re: [PATCH v3 -next 00/15] sysctl: move sysctls from vm_table into its own files

[yukaixiong]

On 2024/10/24 16:59, Joel Granados wrote:
> On Thu, Oct 24, 2024 at 04:07:10PM +0800, yukaixiong wrote:
> ...
>>
>>>>    mm/swap.c                          |  16 ++-
>>>>    mm/swap.h                          |   1 +
>>>>    mm/util.c                          |  67 +++++++--
>>>>    mm/vmscan.c                        |  23 +++
>>>>    mm/vmstat.c                        |  44 +++++-
>>>>    net/sunrpc/auth.c                  |   2 +-
>>>>    security/min_addr.c                |  11 ++
>>>>    23 files changed, 330 insertions(+), 312 deletions(-)
>>>>
>>>> -- 
>>>> 2.34.1
>>>>
>>> General comment for the patchset in general. I would consider making the
>>> new sysctl tables const. There is an effort for doing this and it has
>>> already lanted in linux-next. So if you base your patch from a recent
>>> next release, then it should just work. If you *do* decide to add a
>>> const qualifier, then note that you will create a dependency with the
>>> sysctl patchset currently in next and that will have to go in before.
>>>
>>> Best
>>>
>> Sorry,  I don't understand what is the meaning of "create a dependency
>> with the sysctl patchset".
> The patches in the sysctl subsys that allow you to qualify the ctl_table
> as const are not in mainline yet. They are in linux-next. This means
> that if these patches go into the next kernel release before the
> sysctl-next branch, it will have compilation errors. Therefore the
> sysctl-next branch needs to be pulled in to the new kernel release
> before this patchest. This also means that for this to build properly it
> has to be based on a linux-next release.
>
>> Do you just want me to change all "static struct ctl_table" type table
>> into "static const struct ctl_table" type in my patchset?
> You should const qualify them if the maintainer that is pulling in these
> patches is ok with it. You should *not* const qualify them if the
> maintainer prefers otherwise.
>
> Please get back to me if I did not address your questions.
>
> Best

Thank you! Now， I decide to const qualify them. Maybe, it will be better.