Commit 9bbb63c8 authored by Liu Shixin's avatar Liu Shixin
Browse files

memcg: introduce per-memcg swapin interface 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I7CGGT


CVE: NA

--------------------------------

Add a new per-memcg swapin interface to load data into memory in advance
to improve access efficiency.
Usage:
	# echo 0 > memory.force_swapin

Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent eefe54b2

Documentation/admin-guide/cgroup-v1/memory.rst

+1 −0
Original line number Diff line number Diff line
@@ -78,6 +78,7 @@ Brief summary of control files. 
 memory.stat			     show various statistics

 memory.use_hierarchy		     set/show hierarchical account enabled

 memory.force_empty		     trigger forced page reclaim

 memory.force_swapin		     trigger forced swapin anon page

 memory.pressure_level		     set memory pressure notifications

 memory.swappiness		     set/show swappiness parameter of vmscan

				     (See sysctl's vm.swappiness)

include/linux/mm.h

+1 −0
Original line number Diff line number Diff line
@@ -2650,6 +2650,7 @@ extern int __do_munmap(struct mm_struct *, unsigned long, size_t, 
		       struct list_head *uf, bool downgrade);

extern int do_munmap(struct mm_struct *, unsigned long, size_t,

		     struct list_head *uf);

extern void force_swapin_vma(struct vm_area_struct *vma);

extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior);



extern unsigned long __do_mmap_mm(struct mm_struct *mm, struct file *file,

mm/madvise.c

+19 −0
Original line number Diff line number Diff line
@@ -259,6 +259,25 @@ static void force_shm_swapin_readahead(struct vm_area_struct *vma, 


	lru_add_drain();	/* Push any new pages onto the LRU now */

}



void force_swapin_vma(struct vm_area_struct *vma)

{

	struct file *file = vma->vm_file;



	if (!can_madv_lru_vma(vma))

		return;



	if (!file) {

		walk_page_vma(vma, &swapin_walk_ops, vma);

		lru_add_drain();

	} else if (shmem_mapping(file->f_mapping))

		force_shm_swapin_readahead(vma, vma->vm_start,

			vma->vm_end, file->f_mapping);

}

#else

void force_swapin_vma(struct vm_area_struct *vma)

{

}

#endif		/* CONFIG_SWAP */



/*

mm/memcontrol.c

+33 −0
Original line number Diff line number Diff line
@@ -4106,6 +4106,32 @@ static __init int memcg_swap_qos_sysctls_init(void) 
}

late_initcall(memcg_swap_qos_sysctls_init);

#endif



static int mem_cgroup_task_swapin(struct task_struct *task, void *arg)

{

	struct mm_struct *mm = task->mm;

	struct vm_area_struct *vma;

	struct blk_plug plug;



	mmap_read_lock(mm);

	blk_start_plug(&plug);

	for (vma = mm->mmap; vma; vma = vma->vm_next)

		force_swapin_vma(vma);

	blk_finish_plug(&plug);

	mmap_read_unlock(mm);



	return 0;

}



static ssize_t memory_swapin(struct kernfs_open_file *of, char *buf,

			      size_t nbytes, loff_t off)

{

	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));



	mem_cgroup_scan_tasks(memcg, mem_cgroup_task_swapin, NULL);



	return nbytes;

}

#endif



#ifdef CONFIG_NUMA
@@ -5800,6 +5826,13 @@ static struct cftype mem_cgroup_legacy_files[] = { 
		.name = "reclaim",

		.write = memory_reclaim,

	},

#ifdef CONFIG_MEMCG_SWAP_QOS

	{

		.name = "force_swapin",

		.flags = CFTYPE_NOT_ON_ROOT,

		.write = memory_swapin,

	},

#endif

	{

		.name = "high_async_ratio",

		.flags = CFTYPE_NOT_ON_ROOT,