Commit 00619bcc authored by Jerome Marchand's avatar Jerome Marchand Committed by Linus Torvalds
Browse files

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: default avatarJerome Marchand <jmarchan@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 715ea41e

fs/proc/meminfo.c

+1 −4
Original line number Diff line number Diff line
@@ -24,7 +24,6 @@ static int meminfo_proc_show(struct seq_file *m, void *v) 
{

	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 @@ static int meminfo_proc_show(struct seq_file *m, void *v) 
	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 @@ static int meminfo_proc_show(struct seq_file *m, void *v) 
		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,

include/linux/mman.h

+2 −0
Original line number Diff line number Diff line
@@ -87,4 +87,6 @@ calc_vm_flag_bits(unsigned long flags) 
	       _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 */

mm/mmap.c

+1 −3
Original line number Diff line number Diff line
@@ -179,14 +179,12 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) 
		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

mm/nommu.c

+1 −2
Original line number Diff line number Diff line
@@ -1948,13 +1948,12 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) 
		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

mm/util.c

+13 −0
Original line number Diff line number Diff line
@@ -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 @@ struct address_space *page_mapping(struct page *page) 
	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);

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