1 #ifndef INTERNAL_IO_WQ_H
2 #define INTERNAL_IO_WQ_H
3
4 #include <linux/refcount.h>
5
6 struct io_wq;
7
8 enum {
9 IO_WQ_WORK_CANCEL = 1,
10 IO_WQ_WORK_HASHED = 2,
11 IO_WQ_WORK_UNBOUND = 4,
12 IO_WQ_WORK_CONCURRENT = 16,
13
14 IO_WQ_HASH_SHIFT = 24, /* upper 8 bits are used for hash key */
15 };
16
17 enum io_wq_cancel {
18 IO_WQ_CANCEL_OK, /* cancelled before started */
19 IO_WQ_CANCEL_RUNNING, /* found, running, and attempted cancelled */
20 IO_WQ_CANCEL_NOTFOUND, /* work not found */
21 };
22
23 struct io_wq_work_node {
24 struct io_wq_work_node *next;
25 };
26
27 struct io_wq_work_list {
28 struct io_wq_work_node *first;
29 struct io_wq_work_node *last;
30 };
31
32 #define wq_list_for_each(pos, prv, head) \
33 for (pos = (head)->first, prv = NULL; pos; prv = pos, pos = (pos)->next)
34
35 #define wq_list_for_each_resume(pos, prv) \
36 for (; pos; prv = pos, pos = (pos)->next)
37
38 #define wq_list_empty(list) (READ_ONCE((list)->first) == NULL)
39 #define INIT_WQ_LIST(list) do { \
40 (list)->first = NULL; \
41 } while (0)
42
wq_list_add_after(struct io_wq_work_node * node,struct io_wq_work_node * pos,struct io_wq_work_list * list)43 static inline void wq_list_add_after(struct io_wq_work_node *node,
44 struct io_wq_work_node *pos,
45 struct io_wq_work_list *list)
46 {
47 struct io_wq_work_node *next = pos->next;
48
49 pos->next = node;
50 node->next = next;
51 if (!next)
52 list->last = node;
53 }
54
wq_list_add_tail(struct io_wq_work_node * node,struct io_wq_work_list * list)55 static inline void wq_list_add_tail(struct io_wq_work_node *node,
56 struct io_wq_work_list *list)
57 {
58 node->next = NULL;
59 if (!list->first) {
60 list->last = node;
61 WRITE_ONCE(list->first, node);
62 } else {
63 list->last->next = node;
64 list->last = node;
65 }
66 }
67
wq_list_add_head(struct io_wq_work_node * node,struct io_wq_work_list * list)68 static inline void wq_list_add_head(struct io_wq_work_node *node,
69 struct io_wq_work_list *list)
70 {
71 node->next = list->first;
72 if (!node->next)
73 list->last = node;
74 WRITE_ONCE(list->first, node);
75 }
76
wq_list_cut(struct io_wq_work_list * list,struct io_wq_work_node * last,struct io_wq_work_node * prev)77 static inline void wq_list_cut(struct io_wq_work_list *list,
78 struct io_wq_work_node *last,
79 struct io_wq_work_node *prev)
80 {
81 /* first in the list, if prev==NULL */
82 if (!prev)
83 WRITE_ONCE(list->first, last->next);
84 else
85 prev->next = last->next;
86
87 if (last == list->last)
88 list->last = prev;
89 last->next = NULL;
90 }
91
__wq_list_splice(struct io_wq_work_list * list,struct io_wq_work_node * to)92 static inline void __wq_list_splice(struct io_wq_work_list *list,
93 struct io_wq_work_node *to)
94 {
95 list->last->next = to->next;
96 to->next = list->first;
97 INIT_WQ_LIST(list);
98 }
99
wq_list_splice(struct io_wq_work_list * list,struct io_wq_work_node * to)100 static inline bool wq_list_splice(struct io_wq_work_list *list,
101 struct io_wq_work_node *to)
102 {
103 if (!wq_list_empty(list)) {
104 __wq_list_splice(list, to);
105 return true;
106 }
107 return false;
108 }
109
wq_stack_add_head(struct io_wq_work_node * node,struct io_wq_work_node * stack)110 static inline void wq_stack_add_head(struct io_wq_work_node *node,
111 struct io_wq_work_node *stack)
112 {
113 node->next = stack->next;
114 stack->next = node;
115 }
116
wq_list_del(struct io_wq_work_list * list,struct io_wq_work_node * node,struct io_wq_work_node * prev)117 static inline void wq_list_del(struct io_wq_work_list *list,
118 struct io_wq_work_node *node,
119 struct io_wq_work_node *prev)
120 {
121 wq_list_cut(list, node, prev);
122 }
123
124 static inline
wq_stack_extract(struct io_wq_work_node * stack)125 struct io_wq_work_node *wq_stack_extract(struct io_wq_work_node *stack)
126 {
127 struct io_wq_work_node *node = stack->next;
128
129 stack->next = node->next;
130 return node;
131 }
132
133 struct io_wq_work {
134 struct io_wq_work_node list;
135 unsigned flags;
136 };
137
wq_next_work(struct io_wq_work * work)138 static inline struct io_wq_work *wq_next_work(struct io_wq_work *work)
139 {
140 if (!work->list.next)
141 return NULL;
142
143 return container_of(work->list.next, struct io_wq_work, list);
144 }
145
146 typedef struct io_wq_work *(free_work_fn)(struct io_wq_work *);
147 typedef void (io_wq_work_fn)(struct io_wq_work *);
148
149 struct io_wq_hash {
150 refcount_t refs;
151 unsigned long map;
152 struct wait_queue_head wait;
153 };
154
io_wq_put_hash(struct io_wq_hash * hash)155 static inline void io_wq_put_hash(struct io_wq_hash *hash)
156 {
157 if (refcount_dec_and_test(&hash->refs))
158 kfree(hash);
159 }
160
161 struct io_wq_data {
162 struct io_wq_hash *hash;
163 struct task_struct *task;
164 io_wq_work_fn *do_work;
165 free_work_fn *free_work;
166 };
167
168 struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data);
169 void io_wq_exit_start(struct io_wq *wq);
170 void io_wq_put_and_exit(struct io_wq *wq);
171
172 void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work);
173 void io_wq_hash_work(struct io_wq_work *work, void *val);
174
175 int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask);
176 int io_wq_max_workers(struct io_wq *wq, int *new_count);
177
io_wq_is_hashed(struct io_wq_work * work)178 static inline bool io_wq_is_hashed(struct io_wq_work *work)
179 {
180 return work->flags & IO_WQ_WORK_HASHED;
181 }
182
183 typedef bool (work_cancel_fn)(struct io_wq_work *, void *);
184
185 enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
186 void *data, bool cancel_all);
187
188 #if defined(CONFIG_IO_WQ)
189 extern void io_wq_worker_sleeping(struct task_struct *);
190 extern void io_wq_worker_running(struct task_struct *);
191 #else
io_wq_worker_sleeping(struct task_struct * tsk)192 static inline void io_wq_worker_sleeping(struct task_struct *tsk)
193 {
194 }
io_wq_worker_running(struct task_struct * tsk)195 static inline void io_wq_worker_running(struct task_struct *tsk)
196 {
197 }
198 #endif
199
io_wq_current_is_worker(void)200 static inline bool io_wq_current_is_worker(void)
201 {
202 return in_task() && (current->flags & PF_IO_WORKER) &&
203 current->pf_io_worker;
204 }
205 #endif
206