1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* Copyright (c) 2016 Facebook 3 */ 4 #ifndef __BPF_LRU_LIST_H_ 5 #define __BPF_LRU_LIST_H_ 6 7 #include <linux/list.h> 8 #include <linux/spinlock_types.h> 9 10 #define NR_BPF_LRU_LIST_T (3) 11 #define NR_BPF_LRU_LIST_COUNT (2) 12 #define NR_BPF_LRU_LOCAL_LIST_T (2) 13 #define BPF_LOCAL_LIST_T_OFFSET NR_BPF_LRU_LIST_T 14 15 enum bpf_lru_list_type { 16 BPF_LRU_LIST_T_ACTIVE, 17 BPF_LRU_LIST_T_INACTIVE, 18 BPF_LRU_LIST_T_FREE, 19 BPF_LRU_LOCAL_LIST_T_FREE, 20 BPF_LRU_LOCAL_LIST_T_PENDING, 21 }; 22 23 struct bpf_lru_node { 24 struct list_head list; 25 u16 cpu; 26 u8 type; 27 u8 ref; 28 }; 29 30 struct bpf_lru_list { 31 struct list_head lists[NR_BPF_LRU_LIST_T]; 32 unsigned int counts[NR_BPF_LRU_LIST_COUNT]; 33 /* The next inacitve list rotation starts from here */ 34 struct list_head *next_inactive_rotation; 35 36 raw_spinlock_t lock ____cacheline_aligned_in_smp; 37 }; 38 39 struct bpf_lru_locallist { 40 struct list_head lists[NR_BPF_LRU_LOCAL_LIST_T]; 41 u16 next_steal; 42 raw_spinlock_t lock; 43 }; 44 45 struct bpf_common_lru { 46 struct bpf_lru_list lru_list; 47 struct bpf_lru_locallist __percpu *local_list; 48 }; 49 50 typedef bool (*del_from_htab_func)(void *arg, struct bpf_lru_node *node); 51 52 struct bpf_lru { 53 union { 54 struct bpf_common_lru common_lru; 55 struct bpf_lru_list __percpu *percpu_lru; 56 }; 57 del_from_htab_func del_from_htab; 58 void *del_arg; 59 unsigned int hash_offset; 60 unsigned int nr_scans; 61 bool percpu; 62 }; 63 64 static inline void bpf_lru_node_set_ref(struct bpf_lru_node *node) 65 { 66 /* ref is an approximation on access frequency. It does not 67 * have to be very accurate. Hence, no protection is used. 68 */ 69 if (!node->ref) 70 node->ref = 1; 71 } 72 73 int bpf_lru_init(struct bpf_lru *lru, bool percpu, u32 hash_offset, 74 del_from_htab_func del_from_htab, void *delete_arg); 75 void bpf_lru_populate(struct bpf_lru *lru, void *buf, u32 node_offset, 76 u32 elem_size, u32 nr_elems); 77 void bpf_lru_destroy(struct bpf_lru *lru); 78 struct bpf_lru_node *bpf_lru_pop_free(struct bpf_lru *lru, u32 hash); 79 void bpf_lru_push_free(struct bpf_lru *lru, struct bpf_lru_node *node); 80 void bpf_lru_promote(struct bpf_lru *lru, struct bpf_lru_node *node); 81 82 #endif 83