Commit c077719b authored by KAMEZAWA Hiroyuki's avatar KAMEZAWA Hiroyuki Committed by Linus Torvalds
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memcg: mem+swap controller Kconfig 



Config and control variable for mem+swap controller.

This patch adds CONFIG_CGROUP_MEM_RES_CTLR_SWAP
(memory resource controller swap extension.)

For accounting swap, it's obvious that we have to use additional memory to
remember "who uses swap".  This adds more overhead.  So, it's better to
offer "choice" to users.  This patch adds 2 choices.

This patch adds 2 parameters to enable swap extension or not.
  - CONFIG
  - boot option

Reviewed-by: default avatarDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d13d1443

Documentation/kernel-parameters.txt

+3 −0
Original line number Diff line number Diff line
@@ -1562,6 +1562,9 @@ and is between 256 and 4096 characters. It is defined in the file 


	nosoftlockup	[KNL] Disable the soft-lockup detector.



	noswapaccount	[KNL] Disable accounting of swap in memory resource

			controller. (See Documentation/controllers/memory.txt)



	nosync		[HW,M68K] Disables sync negotiation for all devices.



	notsc		[BUGS=X86-32] Disable Time Stamp Counter

include/linux/memcontrol.h

+3 −0
Original line number Diff line number Diff line
@@ -77,6 +77,9 @@ extern void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, 
extern long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone,

					int priority, enum lru_list lru);



#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP

extern int do_swap_account;

#endif



#else /* CONFIG_CGROUP_MEM_RES_CTLR */

struct mem_cgroup;

init/Kconfig

+17 −0
Original line number Diff line number Diff line
@@ -428,6 +428,23 @@ config CGROUP_MEM_RES_CTLR 
config MM_OWNER

	bool



config CGROUP_MEM_RES_CTLR_SWAP

	bool "Memory Resource Controller Swap Extension(EXPERIMENTAL)"

	depends on CGROUP_MEM_RES_CTLR && SWAP && EXPERIMENTAL

	help

	  Add swap management feature to memory resource controller. When you

	  enable this, you can limit mem+swap usage per cgroup. In other words,

	  when you disable this, memory resource controller has no cares to

	  usage of swap...a process can exhaust all of the swap. This extension

	  is useful when you want to avoid exhaustion swap but this itself

	  adds more overheads and consumes memory for remembering information.

	  Especially if you use 32bit system or small memory system, please

	  be careful about enabling this. When memory resource controller

	  is disabled by boot option, this will be automatically disabled and

	  there will be no overhead from this. Even when you set this config=y,

	  if boot option "noswapaccount" is set, swap will not be accounted.





endmenu



config SYSFS_DEPRECATED

mm/memcontrol.c

+34 −0
Original line number Diff line number Diff line
@@ -41,6 +41,15 @@ 
struct cgroup_subsys mem_cgroup_subsys __read_mostly;

#define MEM_CGROUP_RECLAIM_RETRIES	5



#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP

/* Turned on only when memory cgroup is enabled && really_do_swap_account = 0 */

int do_swap_account __read_mostly;

static int really_do_swap_account __initdata = 1; /* for remember boot option*/

#else

#define do_swap_account		(0)

#endif





/*

 * Statistics for memory cgroup.

 */
@@ -1404,6 +1413,18 @@ static void mem_cgroup_free(struct mem_cgroup *mem) 
}





#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP

static void __init enable_swap_cgroup(void)

{

	if (!mem_cgroup_subsys.disabled && really_do_swap_account)

		do_swap_account = 1;

}

#else

static void __init enable_swap_cgroup(void)

{

}

#endif



static struct cgroup_subsys_state *

mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)

{
@@ -1419,6 +1440,9 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) 
	for_each_node_state(node, N_POSSIBLE)

		if (alloc_mem_cgroup_per_zone_info(mem, node))

			goto free_out;

	/* root ? */

	if (cont->parent == NULL)

		enable_swap_cgroup();



	return &mem->css;

free_out:
@@ -1490,3 +1514,13 @@ struct cgroup_subsys mem_cgroup_subsys = { 
	.attach = mem_cgroup_move_task,

	.early_init = 0,

};



#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP



static int __init disable_swap_account(char *s)

{

	really_do_swap_account = 0;

	return 1;

}

__setup("noswapaccount", disable_swap_account);

#endif

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