Commit 4ca3a69b authored by Sasha Levin's avatar Sasha Levin Committed by Linus Torvalds
Browse files

mm/ksm.c: use new hashtable implementation 



Switch ksm to use the new hashtable implementation.  This reduces the
amount of generic unrelated code in the ksm module.

Signed-off-by: default avatarSasha Levin <levinsasha928@gmail.com>
Acked-by: default avatarHugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 43b5fbbd

mm/ksm.c

+12 −18
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ 
#include <linux/mmu_notifier.h>

#include <linux/swap.h>

#include <linux/ksm.h>

#include <linux/hash.h>

#include <linux/hashtable.h>

#include <linux/freezer.h>

#include <linux/oom.h>
@@ -156,9 +156,8 @@ struct rmap_item { 
static struct rb_root root_stable_tree = RB_ROOT;

static struct rb_root root_unstable_tree = RB_ROOT;



#define MM_SLOTS_HASH_SHIFT 10

#define MM_SLOTS_HASH_HEADS (1 << MM_SLOTS_HASH_SHIFT)

static struct hlist_head mm_slots_hash[MM_SLOTS_HASH_HEADS];

#define MM_SLOTS_HASH_BITS 10

static DEFINE_HASHTABLE(mm_slots_hash, MM_SLOTS_HASH_BITS);



static struct mm_slot ksm_mm_head = {

	.mm_list = LIST_HEAD_INIT(ksm_mm_head.mm_list),
@@ -275,26 +274,21 @@ static inline void free_mm_slot(struct mm_slot *mm_slot) 


static struct mm_slot *get_mm_slot(struct mm_struct *mm)

{

	struct mm_slot *mm_slot;

	struct hlist_head *bucket;

	struct hlist_node *node;

	struct mm_slot *slot;



	hash_for_each_possible(mm_slots_hash, slot, node, link, (unsigned long)mm)

		if (slot->mm == mm)

			return slot;



	bucket = &mm_slots_hash[hash_ptr(mm, MM_SLOTS_HASH_SHIFT)];

	hlist_for_each_entry(mm_slot, node, bucket, link) {

		if (mm == mm_slot->mm)

			return mm_slot;

	}

	return NULL;

}



static void insert_to_mm_slots_hash(struct mm_struct *mm,

				    struct mm_slot *mm_slot)

{

	struct hlist_head *bucket;



	bucket = &mm_slots_hash[hash_ptr(mm, MM_SLOTS_HASH_SHIFT)];

	mm_slot->mm = mm;

	hlist_add_head(&mm_slot->link, bucket);

	hash_add(mm_slots_hash, &mm_slot->link, (unsigned long)mm);

}



static inline int in_stable_tree(struct rmap_item *rmap_item)
@@ -647,7 +641,7 @@ static int unmerge_and_remove_all_rmap_items(void) 
		ksm_scan.mm_slot = list_entry(mm_slot->mm_list.next,

						struct mm_slot, mm_list);

		if (ksm_test_exit(mm)) {

			hlist_del(&mm_slot->link);

			hash_del(&mm_slot->link);

			list_del(&mm_slot->mm_list);

			spin_unlock(&ksm_mmlist_lock);
@@ -1392,7 +1386,7 @@ next_mm: 
		 * or when all VM_MERGEABLE areas have been unmapped (and

		 * mmap_sem then protects against race with MADV_MERGEABLE).

		 */

		hlist_del(&slot->link);

		hash_del(&slot->link);

		list_del(&slot->mm_list);

		spin_unlock(&ksm_mmlist_lock);
@@ -1559,7 +1553,7 @@ void __ksm_exit(struct mm_struct *mm) 
	mm_slot = get_mm_slot(mm);

	if (mm_slot && ksm_scan.mm_slot != mm_slot) {

		if (!mm_slot->rmap_list) {

			hlist_del(&mm_slot->link);

			hash_del(&mm_slot->link);

			list_del(&mm_slot->mm_list);

			easy_to_free = 1;

		} else {

CRA Git | Maintained and supported by SUSTech CRA and CCSE