Commit | Line | Data |
---|---|---|
b5b11890 | 1 | /* SPDX-License-Identifier: GPL-2.0+ */ |
29c00b4a PM |
2 | /* |
3 | * Read-Copy Update definitions shared among RCU implementations. | |
4 | * | |
29c00b4a PM |
5 | * Copyright IBM Corporation, 2011 |
6 | * | |
b5b11890 | 7 | * Author: Paul E. McKenney <paulmck@linux.ibm.com> |
29c00b4a PM |
8 | */ |
9 | ||
10 | #ifndef __LINUX_RCU_H | |
11 | #define __LINUX_RCU_H | |
12 | ||
5cb5c6e1 | 13 | #include <trace/events/rcu.h> |
e99033c5 | 14 | |
2e8c28c2 PM |
15 | /* |
16 | * Grace-period counter management. | |
3636d8d1 FW |
17 | * |
18 | * The two least significant bits contain the control flags. | |
19 | * The most significant bits contain the grace-period sequence counter. | |
20 | * | |
21 | * When both control flags are zero, no grace period is in progress. | |
22 | * When either bit is non-zero, a grace period has started and is in | |
23 | * progress. When the grace period completes, the control flags are reset | |
24 | * to 0 and the grace-period sequence counter is incremented. | |
25 | * | |
26 | * However some specific RCU usages make use of custom values. | |
27 | * | |
28 | * SRCU special control values: | |
29 | * | |
30 | * SRCU_SNP_INIT_SEQ : Invalid/init value set when SRCU node | |
31 | * is initialized. | |
32 | * | |
33 | * SRCU_STATE_IDLE : No SRCU gp is in progress | |
34 | * | |
35 | * SRCU_STATE_SCAN1 : State set by rcu_seq_start(). Indicates | |
36 | * we are scanning the readers on the slot | |
37 | * defined as inactive (there might well | |
38 | * be pending readers that will use that | |
39 | * index, but their number is bounded). | |
40 | * | |
41 | * SRCU_STATE_SCAN2 : State set manually via rcu_seq_set_state() | |
42 | * Indicates we are flipping the readers | |
43 | * index and then scanning the readers on the | |
44 | * slot newly designated as inactive (again, | |
45 | * the number of pending readers that will use | |
46 | * this inactive index is bounded). | |
47 | * | |
48 | * RCU polled GP special control value: | |
49 | * | |
50 | * RCU_GET_STATE_COMPLETED : State value indicating an already-completed | |
51 | * polled GP has completed. This value covers | |
52 | * both the state and the counter of the | |
53 | * grace-period sequence number. | |
2e8c28c2 PM |
54 | */ |
55 | ||
f1ec57a4 | 56 | #define RCU_SEQ_CTR_SHIFT 2 |
031aeee0 PM |
57 | #define RCU_SEQ_STATE_MASK ((1 << RCU_SEQ_CTR_SHIFT) - 1) |
58 | ||
414c1238 PM |
59 | /* Low-order bit definition for polled grace-period APIs. */ |
60 | #define RCU_GET_STATE_COMPLETED 0x1 | |
61 | ||
d9ab0e63 ZN |
62 | extern int sysctl_sched_rt_runtime; |
63 | ||
031aeee0 PM |
64 | /* |
65 | * Return the counter portion of a sequence number previously returned | |
66 | * by rcu_seq_snap() or rcu_seq_current(). | |
67 | */ | |
68 | static inline unsigned long rcu_seq_ctr(unsigned long s) | |
69 | { | |
70 | return s >> RCU_SEQ_CTR_SHIFT; | |
71 | } | |
72 | ||
73 | /* | |
74 | * Return the state portion of a sequence number previously returned | |
75 | * by rcu_seq_snap() or rcu_seq_current(). | |
76 | */ | |
77 | static inline int rcu_seq_state(unsigned long s) | |
78 | { | |
79 | return s & RCU_SEQ_STATE_MASK; | |
80 | } | |
81 | ||
80a7956f PM |
82 | /* |
83 | * Set the state portion of the pointed-to sequence number. | |
84 | * The caller is responsible for preventing conflicting updates. | |
85 | */ | |
86 | static inline void rcu_seq_set_state(unsigned long *sp, int newstate) | |
87 | { | |
88 | WARN_ON_ONCE(newstate & ~RCU_SEQ_STATE_MASK); | |
89 | WRITE_ONCE(*sp, (*sp & ~RCU_SEQ_STATE_MASK) + newstate); | |
90 | } | |
91 | ||
2e8c28c2 PM |
92 | /* Adjust sequence number for start of update-side operation. */ |
93 | static inline void rcu_seq_start(unsigned long *sp) | |
94 | { | |
95 | WRITE_ONCE(*sp, *sp + 1); | |
96 | smp_mb(); /* Ensure update-side operation after counter increment. */ | |
031aeee0 | 97 | WARN_ON_ONCE(rcu_seq_state(*sp) != 1); |
2e8c28c2 PM |
98 | } |
99 | ||
9a414201 PM |
100 | /* Compute the end-of-grace-period value for the specified sequence number. */ |
101 | static inline unsigned long rcu_seq_endval(unsigned long *sp) | |
102 | { | |
103 | return (*sp | RCU_SEQ_STATE_MASK) + 1; | |
104 | } | |
105 | ||
2e8c28c2 PM |
106 | /* Adjust sequence number for end of update-side operation. */ |
107 | static inline void rcu_seq_end(unsigned long *sp) | |
108 | { | |
109 | smp_mb(); /* Ensure update-side operation before counter increment. */ | |
031aeee0 | 110 | WARN_ON_ONCE(!rcu_seq_state(*sp)); |
9a414201 | 111 | WRITE_ONCE(*sp, rcu_seq_endval(sp)); |
2e8c28c2 PM |
112 | } |
113 | ||
0d805a70 JFG |
114 | /* |
115 | * rcu_seq_snap - Take a snapshot of the update side's sequence number. | |
116 | * | |
117 | * This function returns the earliest value of the grace-period sequence number | |
118 | * that will indicate that a full grace period has elapsed since the current | |
119 | * time. Once the grace-period sequence number has reached this value, it will | |
120 | * be safe to invoke all callbacks that have been registered prior to the | |
121 | * current time. This value is the current grace-period number plus two to the | |
122 | * power of the number of low-order bits reserved for state, then rounded up to | |
123 | * the next value in which the state bits are all zero. | |
124 | */ | |
2e8c28c2 PM |
125 | static inline unsigned long rcu_seq_snap(unsigned long *sp) |
126 | { | |
127 | unsigned long s; | |
128 | ||
031aeee0 | 129 | s = (READ_ONCE(*sp) + 2 * RCU_SEQ_STATE_MASK + 1) & ~RCU_SEQ_STATE_MASK; |
2e8c28c2 PM |
130 | smp_mb(); /* Above access must not bleed into critical section. */ |
131 | return s; | |
132 | } | |
133 | ||
8660b7d8 PM |
134 | /* Return the current value the update side's sequence number, no ordering. */ |
135 | static inline unsigned long rcu_seq_current(unsigned long *sp) | |
136 | { | |
137 | return READ_ONCE(*sp); | |
138 | } | |
139 | ||
2e3e5e55 PM |
140 | /* |
141 | * Given a snapshot from rcu_seq_snap(), determine whether or not the | |
142 | * corresponding update-side operation has started. | |
143 | */ | |
144 | static inline bool rcu_seq_started(unsigned long *sp, unsigned long s) | |
145 | { | |
146 | return ULONG_CMP_LT((s - 1) & ~RCU_SEQ_STATE_MASK, READ_ONCE(*sp)); | |
147 | } | |
148 | ||
2e8c28c2 PM |
149 | /* |
150 | * Given a snapshot from rcu_seq_snap(), determine whether or not a | |
151 | * full update-side operation has occurred. | |
152 | */ | |
153 | static inline bool rcu_seq_done(unsigned long *sp, unsigned long s) | |
154 | { | |
155 | return ULONG_CMP_GE(READ_ONCE(*sp), s); | |
156 | } | |
157 | ||
2403e804 PM |
158 | /* |
159 | * Given a snapshot from rcu_seq_snap(), determine whether or not a | |
160 | * full update-side operation has occurred, but do not allow the | |
161 | * (ULONG_MAX / 2) safety-factor/guard-band. | |
162 | */ | |
163 | static inline bool rcu_seq_done_exact(unsigned long *sp, unsigned long s) | |
164 | { | |
165 | unsigned long cur_s = READ_ONCE(*sp); | |
166 | ||
167 | return ULONG_CMP_GE(cur_s, s) || ULONG_CMP_LT(cur_s, s - (2 * RCU_SEQ_STATE_MASK + 1)); | |
168 | } | |
169 | ||
67e14c1e PM |
170 | /* |
171 | * Has a grace period completed since the time the old gp_seq was collected? | |
172 | */ | |
173 | static inline bool rcu_seq_completed_gp(unsigned long old, unsigned long new) | |
174 | { | |
175 | return ULONG_CMP_LT(old, new & ~RCU_SEQ_STATE_MASK); | |
176 | } | |
177 | ||
178 | /* | |
179 | * Has a grace period started since the time the old gp_seq was collected? | |
180 | */ | |
181 | static inline bool rcu_seq_new_gp(unsigned long old, unsigned long new) | |
182 | { | |
183 | return ULONG_CMP_LT((old + RCU_SEQ_STATE_MASK) & ~RCU_SEQ_STATE_MASK, | |
184 | new); | |
185 | } | |
186 | ||
d7219312 PM |
187 | /* |
188 | * Roughly how many full grace periods have elapsed between the collection | |
189 | * of the two specified grace periods? | |
190 | */ | |
191 | static inline unsigned long rcu_seq_diff(unsigned long new, unsigned long old) | |
192 | { | |
2ee5aca5 PM |
193 | unsigned long rnd_diff; |
194 | ||
195 | if (old == new) | |
196 | return 0; | |
197 | /* | |
198 | * Compute the number of grace periods (still shifted up), plus | |
199 | * one if either of new and old is not an exact grace period. | |
200 | */ | |
201 | rnd_diff = (new & ~RCU_SEQ_STATE_MASK) - | |
202 | ((old + RCU_SEQ_STATE_MASK) & ~RCU_SEQ_STATE_MASK) + | |
203 | ((new & RCU_SEQ_STATE_MASK) || (old & RCU_SEQ_STATE_MASK)); | |
204 | if (ULONG_CMP_GE(RCU_SEQ_STATE_MASK, rnd_diff)) | |
205 | return 1; /* Definitely no grace period has elapsed. */ | |
206 | return ((rnd_diff - RCU_SEQ_STATE_MASK - 1) >> RCU_SEQ_CTR_SHIFT) + 2; | |
d7219312 PM |
207 | } |
208 | ||
29c00b4a PM |
209 | /* |
210 | * debug_rcu_head_queue()/debug_rcu_head_unqueue() are used internally | |
7f87c036 PM |
211 | * by call_rcu() and rcu callback execution, and are therefore not part |
212 | * of the RCU API. These are in rcupdate.h because they are used by all | |
213 | * RCU implementations. | |
29c00b4a PM |
214 | */ |
215 | ||
216 | #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD | |
217 | # define STATE_RCU_HEAD_READY 0 | |
218 | # define STATE_RCU_HEAD_QUEUED 1 | |
219 | ||
f9e62f31 | 220 | extern const struct debug_obj_descr rcuhead_debug_descr; |
29c00b4a | 221 | |
ae150184 | 222 | static inline int debug_rcu_head_queue(struct rcu_head *head) |
29c00b4a | 223 | { |
ae150184 PM |
224 | int r1; |
225 | ||
226 | r1 = debug_object_activate(head, &rcuhead_debug_descr); | |
29c00b4a PM |
227 | debug_object_active_state(head, &rcuhead_debug_descr, |
228 | STATE_RCU_HEAD_READY, | |
229 | STATE_RCU_HEAD_QUEUED); | |
ae150184 | 230 | return r1; |
29c00b4a PM |
231 | } |
232 | ||
233 | static inline void debug_rcu_head_unqueue(struct rcu_head *head) | |
234 | { | |
235 | debug_object_active_state(head, &rcuhead_debug_descr, | |
236 | STATE_RCU_HEAD_QUEUED, | |
237 | STATE_RCU_HEAD_READY); | |
238 | debug_object_deactivate(head, &rcuhead_debug_descr); | |
239 | } | |
240 | #else /* !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
ae150184 | 241 | static inline int debug_rcu_head_queue(struct rcu_head *head) |
29c00b4a | 242 | { |
ae150184 | 243 | return 0; |
29c00b4a PM |
244 | } |
245 | ||
246 | static inline void debug_rcu_head_unqueue(struct rcu_head *head) | |
247 | { | |
248 | } | |
249 | #endif /* #else !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ | |
250 | ||
58c53360 PM |
251 | extern int rcu_cpu_stall_suppress_at_boot; |
252 | ||
253 | static inline bool rcu_stall_is_suppressed_at_boot(void) | |
254 | { | |
255 | return rcu_cpu_stall_suppress_at_boot && !rcu_inkernel_boot_has_ended(); | |
256 | } | |
257 | ||
6bfc09e2 PM |
258 | #ifdef CONFIG_RCU_STALL_COMMON |
259 | ||
cdc694b2 | 260 | extern int rcu_cpu_stall_ftrace_dump; |
6bfc09e2 | 261 | extern int rcu_cpu_stall_suppress; |
10462d6f | 262 | extern int rcu_cpu_stall_timeout; |
28b3ae42 | 263 | extern int rcu_exp_cpu_stall_timeout; |
be42f00b | 264 | extern int rcu_cpu_stall_cputime; |
92987fe8 | 265 | extern bool rcu_exp_stall_task_details __read_mostly; |
6bfc09e2 | 266 | int rcu_jiffies_till_stall_check(void); |
28b3ae42 | 267 | int rcu_exp_jiffies_till_stall_check(void); |
6bfc09e2 | 268 | |
58c53360 PM |
269 | static inline bool rcu_stall_is_suppressed(void) |
270 | { | |
271 | return rcu_stall_is_suppressed_at_boot() || rcu_cpu_stall_suppress; | |
272 | } | |
273 | ||
f22ce091 PM |
274 | #define rcu_ftrace_dump_stall_suppress() \ |
275 | do { \ | |
276 | if (!rcu_cpu_stall_suppress) \ | |
277 | rcu_cpu_stall_suppress = 3; \ | |
278 | } while (0) | |
279 | ||
280 | #define rcu_ftrace_dump_stall_unsuppress() \ | |
281 | do { \ | |
282 | if (rcu_cpu_stall_suppress == 3) \ | |
283 | rcu_cpu_stall_suppress = 0; \ | |
284 | } while (0) | |
285 | ||
286 | #else /* #endif #ifdef CONFIG_RCU_STALL_COMMON */ | |
58c53360 PM |
287 | |
288 | static inline bool rcu_stall_is_suppressed(void) | |
289 | { | |
290 | return rcu_stall_is_suppressed_at_boot(); | |
291 | } | |
f22ce091 PM |
292 | #define rcu_ftrace_dump_stall_suppress() |
293 | #define rcu_ftrace_dump_stall_unsuppress() | |
6bfc09e2 PM |
294 | #endif /* #ifdef CONFIG_RCU_STALL_COMMON */ |
295 | ||
0d752924 PM |
296 | /* |
297 | * Strings used in tracepoints need to be exported via the | |
298 | * tracing system such that tools like perf and trace-cmd can | |
299 | * translate the string address pointers to actual text. | |
300 | */ | |
301 | #define TPS(x) tracepoint_string(x) | |
302 | ||
b8989b76 PM |
303 | /* |
304 | * Dump the ftrace buffer, but only one time per callsite per boot. | |
305 | */ | |
306 | #define rcu_ftrace_dump(oops_dump_mode) \ | |
307 | do { \ | |
308 | static atomic_t ___rfd_beenhere = ATOMIC_INIT(0); \ | |
309 | \ | |
310 | if (!atomic_read(&___rfd_beenhere) && \ | |
83b6ca1f PM |
311 | !atomic_xchg(&___rfd_beenhere, 1)) { \ |
312 | tracing_off(); \ | |
f22ce091 | 313 | rcu_ftrace_dump_stall_suppress(); \ |
b8989b76 | 314 | ftrace_dump(oops_dump_mode); \ |
f22ce091 | 315 | rcu_ftrace_dump_stall_unsuppress(); \ |
83b6ca1f | 316 | } \ |
b8989b76 PM |
317 | } while (0) |
318 | ||
aa23c6fb | 319 | void rcu_early_boot_tests(void); |
52d7e48b | 320 | void rcu_test_sync_prims(void); |
aa23c6fb | 321 | |
5f6130fa LJ |
322 | /* |
323 | * This function really isn't for public consumption, but RCU is special in | |
324 | * that context switches can allow the state machine to make progress. | |
325 | */ | |
326 | extern void resched_cpu(int cpu); | |
327 | ||
0cd7e350 | 328 | #if !defined(CONFIG_TINY_RCU) |
2b34c43c PM |
329 | |
330 | #include <linux/rcu_node_tree.h> | |
331 | ||
332 | extern int rcu_num_lvls; | |
e95d68d2 | 333 | extern int num_rcu_lvl[]; |
2b34c43c PM |
334 | extern int rcu_num_nodes; |
335 | static bool rcu_fanout_exact; | |
336 | static int rcu_fanout_leaf; | |
337 | ||
338 | /* | |
339 | * Compute the per-level fanout, either using the exact fanout specified | |
340 | * or balancing the tree, depending on the rcu_fanout_exact boot parameter. | |
341 | */ | |
342 | static inline void rcu_init_levelspread(int *levelspread, const int *levelcnt) | |
343 | { | |
344 | int i; | |
345 | ||
36b5dae6 PM |
346 | for (i = 0; i < RCU_NUM_LVLS; i++) |
347 | levelspread[i] = INT_MIN; | |
2b34c43c PM |
348 | if (rcu_fanout_exact) { |
349 | levelspread[rcu_num_lvls - 1] = rcu_fanout_leaf; | |
350 | for (i = rcu_num_lvls - 2; i >= 0; i--) | |
351 | levelspread[i] = RCU_FANOUT; | |
352 | } else { | |
353 | int ccur; | |
354 | int cprv; | |
355 | ||
356 | cprv = nr_cpu_ids; | |
357 | for (i = rcu_num_lvls - 1; i >= 0; i--) { | |
358 | ccur = levelcnt[i]; | |
359 | levelspread[i] = (cprv + ccur - 1) / ccur; | |
360 | cprv = ccur; | |
361 | } | |
362 | } | |
363 | } | |
364 | ||
b5befe84 FW |
365 | extern void rcu_init_geometry(void); |
366 | ||
7f87c036 | 367 | /* Returns a pointer to the first leaf rcu_node structure. */ |
aedf4ba9 | 368 | #define rcu_first_leaf_node() (rcu_state.level[rcu_num_lvls - 1]) |
5b4c11d5 PM |
369 | |
370 | /* Is this rcu_node a leaf? */ | |
371 | #define rcu_is_leaf_node(rnp) ((rnp)->level == rcu_num_lvls - 1) | |
372 | ||
5257514d | 373 | /* Is this rcu_node the last leaf? */ |
aedf4ba9 | 374 | #define rcu_is_last_leaf_node(rnp) ((rnp) == &rcu_state.node[rcu_num_nodes - 1]) |
5257514d | 375 | |
efbe451d | 376 | /* |
aedf4ba9 | 377 | * Do a full breadth-first scan of the {s,}rcu_node structures for the |
7f87c036 PM |
378 | * specified state structure (for SRCU) or the only rcu_state structure |
379 | * (for RCU). | |
efbe451d | 380 | */ |
95433f72 | 381 | #define _rcu_for_each_node_breadth_first(sp, rnp) \ |
aedf4ba9 PM |
382 | for ((rnp) = &(sp)->node[0]; \ |
383 | (rnp) < &(sp)->node[rcu_num_nodes]; (rnp)++) | |
384 | #define rcu_for_each_node_breadth_first(rnp) \ | |
95433f72 PM |
385 | _rcu_for_each_node_breadth_first(&rcu_state, rnp) |
386 | #define srcu_for_each_node_breadth_first(ssp, rnp) \ | |
387 | _rcu_for_each_node_breadth_first(ssp->srcu_sup, rnp) | |
efbe451d PM |
388 | |
389 | /* | |
7f87c036 PM |
390 | * Scan the leaves of the rcu_node hierarchy for the rcu_state structure. |
391 | * Note that if there is a singleton rcu_node tree with but one rcu_node | |
392 | * structure, this loop -will- visit the rcu_node structure. It is still | |
393 | * a leaf node, even if it is also the root node. | |
efbe451d | 394 | */ |
aedf4ba9 PM |
395 | #define rcu_for_each_leaf_node(rnp) \ |
396 | for ((rnp) = rcu_first_leaf_node(); \ | |
397 | (rnp) < &rcu_state.node[rcu_num_nodes]; (rnp)++) | |
efbe451d PM |
398 | |
399 | /* | |
400 | * Iterate over all possible CPUs in a leaf RCU node. | |
401 | */ | |
402 | #define for_each_leaf_node_possible_cpu(rnp, cpu) \ | |
82dd8419 PM |
403 | for (WARN_ON_ONCE(!rcu_is_leaf_node(rnp)), \ |
404 | (cpu) = cpumask_next((rnp)->grplo - 1, cpu_possible_mask); \ | |
65963d24 PM |
405 | (cpu) <= rnp->grphi; \ |
406 | (cpu) = cpumask_next((cpu), cpu_possible_mask)) | |
407 | ||
408 | /* | |
409 | * Iterate over all CPUs in a leaf RCU node's specified mask. | |
410 | */ | |
411 | #define rcu_find_next_bit(rnp, cpu, mask) \ | |
412 | ((rnp)->grplo + find_next_bit(&(mask), BITS_PER_LONG, (cpu))) | |
413 | #define for_each_leaf_node_cpu_mask(rnp, cpu, mask) \ | |
82dd8419 PM |
414 | for (WARN_ON_ONCE(!rcu_is_leaf_node(rnp)), \ |
415 | (cpu) = rcu_find_next_bit((rnp), 0, (mask)); \ | |
65963d24 PM |
416 | (cpu) <= rnp->grphi; \ |
417 | (cpu) = rcu_find_next_bit((rnp), (cpu) + 1 - (rnp->grplo), (mask))) | |
efbe451d | 418 | |
0cd7e350 PM |
419 | #endif /* !defined(CONFIG_TINY_RCU) */ |
420 | ||
421 | #if !defined(CONFIG_TINY_RCU) || defined(CONFIG_TASKS_RCU_GENERIC) | |
422 | ||
83d40bd3 PM |
423 | /* |
424 | * Wrappers for the rcu_node::lock acquire and release. | |
425 | * | |
426 | * Because the rcu_nodes form a tree, the tree traversal locking will observe | |
427 | * different lock values, this in turn means that an UNLOCK of one level | |
428 | * followed by a LOCK of another level does not imply a full memory barrier; | |
429 | * and most importantly transitivity is lost. | |
430 | * | |
431 | * In order to restore full ordering between tree levels, augment the regular | |
432 | * lock acquire functions with smp_mb__after_unlock_lock(). | |
433 | * | |
434 | * As ->lock of struct rcu_node is a __private field, therefore one should use | |
435 | * these wrappers rather than directly call raw_spin_{lock,unlock}* on ->lock. | |
436 | */ | |
437 | #define raw_spin_lock_rcu_node(p) \ | |
438 | do { \ | |
439 | raw_spin_lock(&ACCESS_PRIVATE(p, lock)); \ | |
440 | smp_mb__after_unlock_lock(); \ | |
441 | } while (0) | |
442 | ||
7dffe017 PM |
443 | #define raw_spin_unlock_rcu_node(p) \ |
444 | do { \ | |
445 | lockdep_assert_irqs_disabled(); \ | |
446 | raw_spin_unlock(&ACCESS_PRIVATE(p, lock)); \ | |
447 | } while (0) | |
83d40bd3 PM |
448 | |
449 | #define raw_spin_lock_irq_rcu_node(p) \ | |
450 | do { \ | |
451 | raw_spin_lock_irq(&ACCESS_PRIVATE(p, lock)); \ | |
452 | smp_mb__after_unlock_lock(); \ | |
453 | } while (0) | |
454 | ||
455 | #define raw_spin_unlock_irq_rcu_node(p) \ | |
7dffe017 PM |
456 | do { \ |
457 | lockdep_assert_irqs_disabled(); \ | |
458 | raw_spin_unlock_irq(&ACCESS_PRIVATE(p, lock)); \ | |
459 | } while (0) | |
83d40bd3 | 460 | |
4e4bea74 | 461 | #define raw_spin_lock_irqsave_rcu_node(p, flags) \ |
83d40bd3 | 462 | do { \ |
4e4bea74 | 463 | raw_spin_lock_irqsave(&ACCESS_PRIVATE(p, lock), flags); \ |
83d40bd3 PM |
464 | smp_mb__after_unlock_lock(); \ |
465 | } while (0) | |
466 | ||
4e4bea74 | 467 | #define raw_spin_unlock_irqrestore_rcu_node(p, flags) \ |
7dffe017 PM |
468 | do { \ |
469 | lockdep_assert_irqs_disabled(); \ | |
470 | raw_spin_unlock_irqrestore(&ACCESS_PRIVATE(p, lock), flags); \ | |
471 | } while (0) | |
83d40bd3 PM |
472 | |
473 | #define raw_spin_trylock_rcu_node(p) \ | |
474 | ({ \ | |
475 | bool ___locked = raw_spin_trylock(&ACCESS_PRIVATE(p, lock)); \ | |
476 | \ | |
477 | if (___locked) \ | |
478 | smp_mb__after_unlock_lock(); \ | |
479 | ___locked; \ | |
480 | }) | |
481 | ||
a32e01ee MW |
482 | #define raw_lockdep_assert_held_rcu_node(p) \ |
483 | lockdep_assert_held(&ACCESS_PRIVATE(p, lock)) | |
484 | ||
0cd7e350 | 485 | #endif // #if !defined(CONFIG_TINY_RCU) || defined(CONFIG_TASKS_RCU_GENERIC) |
2b34c43c | 486 | |
25c36329 PM |
487 | #ifdef CONFIG_TINY_RCU |
488 | /* Tiny RCU doesn't expedite, as its purpose in life is instead to be tiny. */ | |
7414fac0 PM |
489 | static inline bool rcu_gp_is_normal(void) { return true; } |
490 | static inline bool rcu_gp_is_expedited(void) { return false; } | |
6efdda8b | 491 | static inline bool rcu_async_should_hurry(void) { return false; } |
7414fac0 PM |
492 | static inline void rcu_expedite_gp(void) { } |
493 | static inline void rcu_unexpedite_gp(void) { } | |
6efdda8b JFG |
494 | static inline void rcu_async_hurry(void) { } |
495 | static inline void rcu_async_relax(void) { } | |
25c36329 PM |
496 | #else /* #ifdef CONFIG_TINY_RCU */ |
497 | bool rcu_gp_is_normal(void); /* Internal RCU use. */ | |
498 | bool rcu_gp_is_expedited(void); /* Internal RCU use. */ | |
6efdda8b | 499 | bool rcu_async_should_hurry(void); /* Internal RCU use. */ |
25c36329 PM |
500 | void rcu_expedite_gp(void); |
501 | void rcu_unexpedite_gp(void); | |
6efdda8b JFG |
502 | void rcu_async_hurry(void); |
503 | void rcu_async_relax(void); | |
25c36329 | 504 | void rcupdate_announce_bootup_oddness(void); |
474d0997 | 505 | #ifdef CONFIG_TASKS_RCU_GENERIC |
e21408ce | 506 | void show_rcu_tasks_gp_kthreads(void); |
474d0997 PM |
507 | #else /* #ifdef CONFIG_TASKS_RCU_GENERIC */ |
508 | static inline void show_rcu_tasks_gp_kthreads(void) {} | |
509 | #endif /* #else #ifdef CONFIG_TASKS_RCU_GENERIC */ | |
25c36329 PM |
510 | #endif /* #else #ifdef CONFIG_TINY_RCU */ |
511 | ||
e0a34641 AB |
512 | #ifdef CONFIG_TASKS_RCU |
513 | struct task_struct *get_rcu_tasks_gp_kthread(void); | |
514 | #endif // # ifdef CONFIG_TASKS_RCU | |
515 | ||
516 | #ifdef CONFIG_TASKS_RUDE_RCU | |
517 | struct task_struct *get_rcu_tasks_rude_gp_kthread(void); | |
518 | #endif // # ifdef CONFIG_TASKS_RUDE_RCU | |
519 | ||
82118249 PM |
520 | #define RCU_SCHEDULER_INACTIVE 0 |
521 | #define RCU_SCHEDULER_INIT 1 | |
522 | #define RCU_SCHEDULER_RUNNING 2 | |
523 | ||
cad7b389 PM |
524 | enum rcutorture_type { |
525 | RCU_FLAVOR, | |
cad7b389 | 526 | RCU_TASKS_FLAVOR, |
3d6e43c7 | 527 | RCU_TASKS_RUDE_FLAVOR, |
c1a76c0b | 528 | RCU_TASKS_TRACING_FLAVOR, |
c682db55 | 529 | RCU_TRIVIAL_FLAVOR, |
cad7b389 PM |
530 | SRCU_FLAVOR, |
531 | INVALID_RCU_FLAVOR | |
532 | }; | |
533 | ||
3cb278e7 JFG |
534 | #if defined(CONFIG_RCU_LAZY) |
535 | unsigned long rcu_lazy_get_jiffies_till_flush(void); | |
536 | void rcu_lazy_set_jiffies_till_flush(unsigned long j); | |
537 | #else | |
538 | static inline unsigned long rcu_lazy_get_jiffies_till_flush(void) { return 0; } | |
539 | static inline void rcu_lazy_set_jiffies_till_flush(unsigned long j) { } | |
540 | #endif | |
541 | ||
b3e627d3 | 542 | #if defined(CONFIG_TREE_RCU) |
cad7b389 | 543 | void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags, |
aebc8264 | 544 | unsigned long *gp_seq); |
cad7b389 PM |
545 | void do_trace_rcu_torture_read(const char *rcutorturename, |
546 | struct rcu_head *rhp, | |
547 | unsigned long secs, | |
548 | unsigned long c_old, | |
549 | unsigned long c); | |
55b2dcf5 | 550 | void rcu_gp_set_torture_wait(int duration); |
cad7b389 PM |
551 | #else |
552 | static inline void rcutorture_get_gp_data(enum rcutorture_type test_type, | |
aebc8264 | 553 | int *flags, unsigned long *gp_seq) |
cad7b389 PM |
554 | { |
555 | *flags = 0; | |
aebc8264 | 556 | *gp_seq = 0; |
cad7b389 | 557 | } |
cad7b389 PM |
558 | #ifdef CONFIG_RCU_TRACE |
559 | void do_trace_rcu_torture_read(const char *rcutorturename, | |
560 | struct rcu_head *rhp, | |
561 | unsigned long secs, | |
562 | unsigned long c_old, | |
563 | unsigned long c); | |
564 | #else | |
565 | #define do_trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \ | |
566 | do { } while (0) | |
567 | #endif | |
55b2dcf5 | 568 | static inline void rcu_gp_set_torture_wait(int duration) { } |
cad7b389 PM |
569 | #endif |
570 | ||
c682db55 PM |
571 | #if IS_ENABLED(CONFIG_RCU_TORTURE_TEST) || IS_MODULE(CONFIG_RCU_TORTURE_TEST) |
572 | long rcutorture_sched_setaffinity(pid_t pid, const struct cpumask *in_mask); | |
573 | #endif | |
574 | ||
cad7b389 PM |
575 | #ifdef CONFIG_TINY_SRCU |
576 | ||
577 | static inline void srcutorture_get_gp_data(enum rcutorture_type test_type, | |
578 | struct srcu_struct *sp, int *flags, | |
aebc8264 | 579 | unsigned long *gp_seq) |
cad7b389 PM |
580 | { |
581 | if (test_type != SRCU_FLAVOR) | |
582 | return; | |
583 | *flags = 0; | |
aebc8264 | 584 | *gp_seq = sp->srcu_idx; |
cad7b389 PM |
585 | } |
586 | ||
587 | #elif defined(CONFIG_TREE_SRCU) | |
588 | ||
589 | void srcutorture_get_gp_data(enum rcutorture_type test_type, | |
590 | struct srcu_struct *sp, int *flags, | |
aebc8264 | 591 | unsigned long *gp_seq); |
cad7b389 | 592 | |
cad7b389 PM |
593 | #endif |
594 | ||
e3c8d51e | 595 | #ifdef CONFIG_TINY_RCU |
7d0c9c50 | 596 | static inline bool rcu_dynticks_zero_in_eqs(int cpu, int *vp) { return false; } |
17ef2fe9 | 597 | static inline unsigned long rcu_get_gp_seq(void) { return 0; } |
7414fac0 | 598 | static inline unsigned long rcu_exp_batches_completed(void) { return 0; } |
7414fac0 PM |
599 | static inline unsigned long |
600 | srcu_batches_completed(struct srcu_struct *sp) { return 0; } | |
601 | static inline void rcu_force_quiescent_state(void) { } | |
0260b92e | 602 | static inline bool rcu_check_boost_fail(unsigned long gp_state, int *cpup) { return true; } |
7414fac0 | 603 | static inline void show_rcu_gp_kthreads(void) { } |
4babd855 | 604 | static inline int rcu_get_gp_kthreads_prio(void) { return 0; } |
e0aff973 | 605 | static inline void rcu_fwd_progress_check(unsigned long j) { } |
99d6a2ac PM |
606 | static inline void rcu_gp_slow_register(atomic_t *rgssp) { } |
607 | static inline void rcu_gp_slow_unregister(atomic_t *rgssp) { } | |
e3c8d51e | 608 | #else /* #ifdef CONFIG_TINY_RCU */ |
7d0c9c50 | 609 | bool rcu_dynticks_zero_in_eqs(int cpu, int *vp); |
17ef2fe9 | 610 | unsigned long rcu_get_gp_seq(void); |
e3c8d51e | 611 | unsigned long rcu_exp_batches_completed(void); |
5a0465e1 | 612 | unsigned long srcu_batches_completed(struct srcu_struct *sp); |
0260b92e | 613 | bool rcu_check_boost_fail(unsigned long gp_state, int *cpup); |
e3c8d51e | 614 | void show_rcu_gp_kthreads(void); |
4babd855 | 615 | int rcu_get_gp_kthreads_prio(void); |
e0aff973 | 616 | void rcu_fwd_progress_check(unsigned long j); |
e3c8d51e | 617 | void rcu_force_quiescent_state(void); |
ad7c946b | 618 | extern struct workqueue_struct *rcu_gp_wq; |
9621fbee KS |
619 | #ifdef CONFIG_RCU_EXP_KTHREAD |
620 | extern struct kthread_worker *rcu_exp_gp_kworker; | |
621 | extern struct kthread_worker *rcu_exp_par_gp_kworker; | |
622 | #else /* !CONFIG_RCU_EXP_KTHREAD */ | |
25f3d7ef | 623 | extern struct workqueue_struct *rcu_par_gp_wq; |
9621fbee | 624 | #endif /* CONFIG_RCU_EXP_KTHREAD */ |
99d6a2ac PM |
625 | void rcu_gp_slow_register(atomic_t *rgssp); |
626 | void rcu_gp_slow_unregister(atomic_t *rgssp); | |
e3c8d51e PM |
627 | #endif /* #else #ifdef CONFIG_TINY_RCU */ |
628 | ||
44c65ff2 | 629 | #ifdef CONFIG_RCU_NOCB_CPU |
5ab7ab83 | 630 | void rcu_bind_current_to_nocb(void); |
3d54f798 | 631 | #else |
5ab7ab83 | 632 | static inline void rcu_bind_current_to_nocb(void) { } |
3d54f798 PM |
633 | #endif |
634 | ||
27c0f144 PM |
635 | #if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_RCU) |
636 | void show_rcu_tasks_classic_gp_kthread(void); | |
637 | #else | |
638 | static inline void show_rcu_tasks_classic_gp_kthread(void) {} | |
639 | #endif | |
640 | #if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_RUDE_RCU) | |
641 | void show_rcu_tasks_rude_gp_kthread(void); | |
642 | #else | |
643 | static inline void show_rcu_tasks_rude_gp_kthread(void) {} | |
644 | #endif | |
645 | #if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_TRACE_RCU) | |
646 | void show_rcu_tasks_trace_gp_kthread(void); | |
647 | #else | |
648 | static inline void show_rcu_tasks_trace_gp_kthread(void) {} | |
649 | #endif | |
650 | ||
401b0de3 PM |
651 | #ifdef CONFIG_TINY_RCU |
652 | static inline bool rcu_cpu_beenfullyonline(int cpu) { return true; } | |
653 | #else | |
654 | bool rcu_cpu_beenfullyonline(int cpu); | |
655 | #endif | |
656 | ||
29c00b4a | 657 | #endif /* __LINUX_RCU_H */ |