mm: factor commit limit calculation
The same calculation is currently done in three differents places.
Factor that code so future changes has to be made at only one place.
[akpm@linux-foundation.org: uninline vm_commit_limit()]
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index 59d85d6..c805d5b 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -24,7 +24,6 @@
{
struct sysinfo i;
unsigned long committed;
- unsigned long allowed;
struct vmalloc_info vmi;
long cached;
unsigned long pages[NR_LRU_LISTS];
@@ -37,8 +36,6 @@
si_meminfo(&i);
si_swapinfo(&i);
committed = percpu_counter_read_positive(&vm_committed_as);
- allowed = ((totalram_pages - hugetlb_total_pages())
- * sysctl_overcommit_ratio / 100) + total_swap_pages;
cached = global_page_state(NR_FILE_PAGES) -
total_swapcache_pages() - i.bufferram;
@@ -147,7 +144,7 @@
K(global_page_state(NR_UNSTABLE_NFS)),
K(global_page_state(NR_BOUNCE)),
K(global_page_state(NR_WRITEBACK_TEMP)),
- K(allowed),
+ K(vm_commit_limit()),
K(committed),
(unsigned long)VMALLOC_TOTAL >> 10,
vmi.used >> 10,
diff --git a/include/linux/mman.h b/include/linux/mman.h
index 92dc257..7f7f8da 100644
--- a/include/linux/mman.h
+++ b/include/linux/mman.h
@@ -87,4 +87,6 @@
_calc_vm_trans(flags, MAP_DENYWRITE, VM_DENYWRITE ) |
_calc_vm_trans(flags, MAP_LOCKED, VM_LOCKED );
}
+
+unsigned long vm_commit_limit(void);
#endif /* _LINUX_MMAN_H */
diff --git a/mm/mmap.c b/mm/mmap.c
index 3d3e224..803048e 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -179,14 +179,12 @@
goto error;
}
- allowed = (totalram_pages - hugetlb_total_pages())
- * sysctl_overcommit_ratio / 100;
+ allowed = vm_commit_limit();
/*
* Reserve some for root
*/
if (!cap_sys_admin)
allowed -= sysctl_admin_reserve_kbytes >> (PAGE_SHIFT - 10);
- allowed += total_swap_pages;
/*
* Don't let a single process grow so big a user can't recover
diff --git a/mm/nommu.c b/mm/nommu.c
index ecd1f15..d8a957b 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1948,13 +1948,12 @@
goto error;
}
- allowed = totalram_pages * sysctl_overcommit_ratio / 100;
+ allowed = vm_commit_limit();
/*
* Reserve some 3% for root
*/
if (!cap_sys_admin)
allowed -= sysctl_admin_reserve_kbytes >> (PAGE_SHIFT - 10);
- allowed += total_swap_pages;
/*
* Don't let a single process grow so big a user can't recover
diff --git a/mm/util.c b/mm/util.c
index eaf63fc2..f7bc209 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -7,6 +7,9 @@
#include <linux/security.h>
#include <linux/swap.h>
#include <linux/swapops.h>
+#include <linux/mman.h>
+#include <linux/hugetlb.h>
+
#include <asm/uaccess.h>
#include "internal.h"
@@ -398,6 +401,16 @@
return mapping;
}
+/*
+ * Committed memory limit enforced when OVERCOMMIT_NEVER policy is used
+ */
+unsigned long vm_commit_limit(void)
+{
+ return ((totalram_pages - hugetlb_total_pages())
+ * sysctl_overcommit_ratio / 100) + total_swap_pages;
+}
+
+
/* Tracepoints definitions. */
EXPORT_TRACEPOINT_SYMBOL(kmalloc);
EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);