From 7e736b8e36ff87080890690670c90c91d6d80091 Mon Sep 17 00:00:00 2001 From: Qi Zheng Date: Wed, 31 Aug 2022 11:19:45 +0800 Subject: [PATCH] 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 Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Mike Rapoport Cc: Minchan Kim Cc: Vlastimil Babka Cc: Yang Shi Signed-off-by: Andrew Morton --- mm/mm_slot.h | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 mm/mm_slot.h diff --git a/mm/mm_slot.h b/mm/mm_slot.h new file mode 100644 index 000000000000..83f18ed1c4bd --- /dev/null +++ b/mm/mm_slot.h @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 + +#ifndef _LINUX_MM_SLOT_H +#define _LINUX_MM_SLOT_H + +#include +#include + +/* + * 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 */