Commit 94b6da5a authored by KAMEZAWA Hiroyuki's avatar KAMEZAWA Hiroyuki Committed by Linus Torvalds
Browse files

memcg: fix page_cgroup allocation 



page_cgroup_init() is called from mem_cgroup_init(). But at this
point, we cannot call alloc_bootmem().
(and this caused panic at boot.)

This patch moves page_cgroup_init() to init/main.c.

Time table is following:
==
  parse_args(). # we can trust mem_cgroup_subsys.disabled bit after this.
  ....
  cgroup_init_early()  # "early" init of cgroup.
  ....
  setup_arch()         # memmap is allocated.
  ...
  page_cgroup_init();
  mem_init();   # we cannot call alloc_bootmem after this.
  ....
  cgroup_init() # mem_cgroup is initialized.
==

Before page_cgroup_init(), mem_map must be initialized. So,
I added page_cgroup_init() to init/main.c directly.

(*) maybe this is not very clean but
    - cgroup_init_early() is too early
    - in cgroup_init(), we have to use vmalloc instead of alloc_bootmem().
    use of vmalloc area in x86-32 is important and we should avoid very large
    vmalloc() in x86-32. So, we want to use alloc_bootmem() and added page_cgroup_init()
    directly to init/main.c

[akpm@linux-foundation.org: remove unneeded/bad mem_cgroup_subsys declaration]
[akpm@linux-foundation.org: fix build]
Acked-by: default avatarBalbir Singh <balbir@linux.vnet.ibm.com>
Tested-by: default avatarBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent be07c4ed

include/linux/page_cgroup.h

+5 −0
Original line number Diff line number Diff line
@@ -99,5 +99,10 @@ static inline struct page_cgroup *lookup_page_cgroup(struct page *page) 
{

	return NULL;

}



static inline void page_cgroup_init(void)

{

}



#endif

#endif

init/main.c

+2 −0
Original line number Diff line number Diff line
@@ -52,6 +52,7 @@ 
#include <linux/key.h>

#include <linux/unwind.h>

#include <linux/buffer_head.h>

#include <linux/page_cgroup.h>

#include <linux/debug_locks.h>

#include <linux/debugobjects.h>

#include <linux/lockdep.h>
@@ -647,6 +648,7 @@ asmlinkage void __init start_kernel(void) 
	vmalloc_init();

	vfs_caches_init_early();

	cpuset_init_early();

	page_cgroup_init();

	mem_init();

	enable_debug_pagealloc();

	cpu_hotplug_init();

mm/memcontrol.c

+0 −1
Original line number Diff line number Diff line
@@ -1088,7 +1088,6 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) 
	int node;



	if (unlikely((cont->parent) == NULL)) {

		page_cgroup_init();

		mem = &init_mem_cgroup;

	} else {

		mem = mem_cgroup_alloc();

mm/page_cgroup.c

+25 −7
Original line number Diff line number Diff line
@@ -4,8 +4,10 @@ 
#include <linux/bit_spinlock.h>

#include <linux/page_cgroup.h>

#include <linux/hash.h>

#include <linux/slab.h>

#include <linux/memory.h>

#include <linux/vmalloc.h>

#include <linux/cgroup.h>



static void __meminit

__init_page_cgroup(struct page_cgroup *pc, unsigned long pfn)
@@ -67,6 +69,9 @@ void __init page_cgroup_init(void) 


	int nid, fail;



	if (mem_cgroup_subsys.disabled)

		return;



	for_each_online_node(nid)  {

		fail = alloc_node_page_cgroup(nid);

		if (fail)
@@ -107,9 +112,14 @@ int __meminit init_section_page_cgroup(unsigned long pfn) 
	nid = page_to_nid(pfn_to_page(pfn));



	table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION;

	if (slab_is_available()) {

		base = kmalloc_node(table_size, GFP_KERNEL, nid);

		if (!base)

			base = vmalloc_node(table_size, nid);

	} else {

		base = __alloc_bootmem_node_nopanic(NODE_DATA(nid), table_size,

				PAGE_SIZE, __pa(MAX_DMA_ADDRESS));

	}



	if (!base) {

		printk(KERN_ERR "page cgroup allocation failure\n");
@@ -136,11 +146,16 @@ void __free_page_cgroup(unsigned long pfn) 
	if (!ms || !ms->page_cgroup)

		return;

	base = ms->page_cgroup + pfn;

	ms->page_cgroup = NULL;

	if (is_vmalloc_addr(base))

	if (is_vmalloc_addr(base)) {

		vfree(base);

	else

		ms->page_cgroup = NULL;

	} else {

		struct page *page = virt_to_page(base);

		if (!PageReserved(page)) { /* Is bootmem ? */

			kfree(base);

			ms->page_cgroup = NULL;

		}

	}

}



int online_page_cgroup(unsigned long start_pfn,
@@ -214,6 +229,9 @@ void __init page_cgroup_init(void) 
	unsigned long pfn;

	int fail = 0;



	if (mem_cgroup_subsys.disabled)

		return;



	for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) {

		if (!pfn_present(pfn))

			continue;

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