mm: introduce common struct mm_slot

Patch series "add common struct mm_slot and use it in THP and KSM", v2.

At present, both THP and KSM module have similar structures mm_slot for
organizing and recording the information required for scanning mm, and
each defines the following exactly the same operation functions:

 - alloc_mm_slot
 - free_mm_slot
 - get_mm_slot
 - insert_to_mm_slots_hash

In order to de-duplicate these codes, this patchset introduces a common
struct mm_slot, and lets THP and KSM to use it.


This patch (of 7):

At present, both THP and KSM module have similar structures mm_slot for
organizing and recording the information required for scanning mm, and
each defines the following exactly the same operation functions:

 - alloc_mm_slot
 - free_mm_slot
 - get_mm_slot
 - insert_to_mm_slots_hash

In order to de-duplicate these codes, this patch introduces a common
struct mm_slot, and subsequent patches will let THP and KSM to use it.

Link: https://lkml.kernel.org/r/20220831031951.43152-1-zhengqi.arch@bytedance.com
Link: https://lkml.kernel.org/r/20220831031951.43152-2-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Qi Zheng 2022-08-31 11:19:45 +08:00 committed by Andrew Morton
parent 21b7bdb504
commit 7e736b8e36
1 changed files with 55 additions and 0 deletions

55
mm/mm_slot.h Normal file
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// SPDX-License-Identifier: GPL-2.0
#ifndef _LINUX_MM_SLOT_H
#define _LINUX_MM_SLOT_H
#include <linux/hashtable.h>
#include <linux/slab.h>
/*
* struct mm_slot - hash lookup from mm to mm_slot
* @hash: link to the mm_slots hash list
* @mm_node: link into the mm_slots list
* @mm: the mm that this information is valid for
*/
struct mm_slot {
struct hlist_node hash;
struct list_head mm_node;
struct mm_struct *mm;
};
#define mm_slot_entry(ptr, type, member) \
container_of(ptr, type, member)
static inline void *mm_slot_alloc(struct kmem_cache *cache)
{
if (!cache) /* initialization failed */
return NULL;
return kmem_cache_zalloc(cache, GFP_KERNEL);
}
static inline void mm_slot_free(struct kmem_cache *cache, void *objp)
{
kmem_cache_free(cache, objp);
}
#define mm_slot_lookup(_hashtable, _mm) \
({ \
struct mm_slot *tmp_slot, *mm_slot = NULL; \
\
hash_for_each_possible(_hashtable, tmp_slot, hash, (unsigned long)_mm) \
if (_mm == tmp_slot->mm) { \
mm_slot = tmp_slot; \
break; \
} \
\
mm_slot; \
})
#define mm_slot_insert(_hashtable, _mm, _mm_slot) \
({ \
_mm_slot->mm = _mm; \
hash_add(_hashtable, &_mm_slot->hash, (unsigned long)_mm); \
})
#endif /* _LINUX_MM_SLOT_H */