[PATCH 1/3] mm: move max_map_count bits into mm.h

From: Andrey Ryabinin
Date: Wed Feb 10 2016 - 09:51:27 EST


max_map_count sysctl unrelated to scheduler. Move its bits from
include/linux/sched/sysctl.h to include/linux/mm.h.

Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
---
include/linux/mm.h | 21 +++++++++++++++++++++
include/linux/sched/sysctl.h | 21 ---------------------
mm/mmap.c | 1 -
mm/mremap.c | 1 -
mm/nommu.c | 1 -
5 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 516e149..979bc83 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -82,6 +82,27 @@ extern int mmap_rnd_compat_bits __read_mostly;
#define mm_forbids_zeropage(X) (0)
#endif

+/*
+ * Default maximum number of active map areas, this limits the number of vmas
+ * per mm struct. Users can overwrite this number by sysctl but there is a
+ * problem.
+ *
+ * When a program's coredump is generated as ELF format, a section is created
+ * per a vma. In ELF, the number of sections is represented in unsigned short.
+ * This means the number of sections should be smaller than 65535 at coredump.
+ * Because the kernel adds some informative sections to a image of program at
+ * generating coredump, we need some margin. The number of extra sections is
+ * 1-3 now and depends on arch. We use "5" as safe margin, here.
+ *
+ * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
+ * not a hard limit any more. Although some userspace tools can be surprised by
+ * that.
+ */
+#define MAPCOUNT_ELF_CORE_MARGIN (5)
+#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
+
+extern int sysctl_max_map_count;
+
extern unsigned long sysctl_user_reserve_kbytes;
extern unsigned long sysctl_admin_reserve_kbytes;

diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h
index c9e4731..5f7d334 100644
--- a/include/linux/sched/sysctl.h
+++ b/include/linux/sched/sysctl.h
@@ -14,27 +14,6 @@ extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
enum { sysctl_hung_task_timeout_secs = 0 };
#endif

-/*
- * Default maximum number of active map areas, this limits the number of vmas
- * per mm struct. Users can overwrite this number by sysctl but there is a
- * problem.
- *
- * When a program's coredump is generated as ELF format, a section is created
- * per a vma. In ELF, the number of sections is represented in unsigned short.
- * This means the number of sections should be smaller than 65535 at coredump.
- * Because the kernel adds some informative sections to a image of program at
- * generating coredump, we need some margin. The number of extra sections is
- * 1-3 now and depends on arch. We use "5" as safe margin, here.
- *
- * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
- * not a hard limit any more. Although some userspace tools can be surprised by
- * that.
- */
-#define MAPCOUNT_ELF_CORE_MARGIN (5)
-#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
-
-extern int sysctl_max_map_count;
-
extern unsigned int sysctl_sched_latency;
extern unsigned int sysctl_sched_min_granularity;
extern unsigned int sysctl_sched_wakeup_granularity;
diff --git a/mm/mmap.c b/mm/mmap.c
index 2f2415a..4afb2a2 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -37,7 +37,6 @@
#include <linux/khugepaged.h>
#include <linux/uprobes.h>
#include <linux/rbtree_augmented.h>
-#include <linux/sched/sysctl.h>
#include <linux/notifier.h>
#include <linux/memory.h>
#include <linux/printk.h>
diff --git a/mm/mremap.c b/mm/mremap.c
index d77946a..e8329d1 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -20,7 +20,6 @@
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/mmu_notifier.h>
-#include <linux/sched/sysctl.h>
#include <linux/uaccess.h>
#include <linux/mm-arch-hooks.h>

diff --git a/mm/nommu.c b/mm/nommu.c
index fbf6f0f1..9bdf8b1 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -33,7 +33,6 @@
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/audit.h>
-#include <linux/sched/sysctl.h>
#include <linux/printk.h>

#include <asm/uaccess.h>
--
2.4.10