hc
2024-05-10 61598093bbdd283a7edc367d900f223070ead8d2
kernel/kernel/rcu/tree.h
....@@ -1,25 +1,12 @@
1
+/* SPDX-License-Identifier: GPL-2.0+ */
12 /*
23 * Read-Copy Update mechanism for mutual exclusion (tree-based version)
34 * Internal non-public definitions.
45 *
5
- * This program is free software; you can redistribute it and/or modify
6
- * it under the terms of the GNU General Public License as published by
7
- * the Free Software Foundation; either version 2 of the License, or
8
- * (at your option) any later version.
9
- *
10
- * This program is distributed in the hope that it will be useful,
11
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
12
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13
- * GNU General Public License for more details.
14
- *
15
- * You should have received a copy of the GNU General Public License
16
- * along with this program; if not, you can access it online at
17
- * http://www.gnu.org/licenses/gpl-2.0.html.
18
- *
196 * Copyright IBM Corporation, 2008
207 *
218 * Author: Ingo Molnar <mingo@elte.hu>
22
- * Paul E. McKenney <paulmck@linux.vnet.ibm.com>
9
+ * Paul E. McKenney <paulmck@linux.ibm.com>
2310 */
2411
2512 #include <linux/cache.h>
....@@ -29,39 +16,12 @@
2916 #include <linux/cpumask.h>
3017 #include <linux/seqlock.h>
3118 #include <linux/swait.h>
32
-#include <linux/stop_machine.h>
3319 #include <linux/rcu_node_tree.h>
3420
3521 #include "rcu_segcblist.h"
3622
37
-/*
38
- * Dynticks per-CPU state.
39
- */
40
-struct rcu_dynticks {
41
- long dynticks_nesting; /* Track process nesting level. */
42
- long dynticks_nmi_nesting; /* Track irq/NMI nesting level. */
43
- atomic_t dynticks; /* Even value for idle, else odd. */
44
- bool rcu_need_heavy_qs; /* GP old, need heavy quiescent state. */
45
- unsigned long rcu_qs_ctr; /* Light universal quiescent state ctr. */
46
- bool rcu_urgent_qs; /* GP old need light quiescent state. */
47
-#ifdef CONFIG_RCU_FAST_NO_HZ
48
- bool all_lazy; /* Are all CPU's CBs lazy? */
49
- unsigned long nonlazy_posted;
50
- /* # times non-lazy CBs posted to CPU. */
51
- unsigned long nonlazy_posted_snap;
52
- /* idle-period nonlazy_posted snapshot. */
53
- unsigned long last_accelerate;
54
- /* Last jiffy CBs were accelerated. */
55
- unsigned long last_advance_all;
56
- /* Last jiffy CBs were all advanced. */
57
- int tick_nohz_enabled_snap; /* Previously seen value from sysfs. */
58
-#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
59
-};
60
-
6123 /* Communicate arguments to a workqueue handler. */
6224 struct rcu_exp_work {
63
- smp_call_func_t rew_func;
64
- struct rcu_state *rew_rsp;
6525 unsigned long rew_s;
6626 struct work_struct rew_work;
6727 };
....@@ -81,8 +41,8 @@
8141 raw_spinlock_t __private lock; /* Root rcu_node's lock protects */
8242 /* some rcu_state fields as well as */
8343 /* following. */
84
- unsigned long gp_seq; /* Track rsp->rcu_gp_seq. */
85
- unsigned long gp_seq_needed; /* Track rsp->rcu_gp_seq_needed. */
44
+ unsigned long gp_seq; /* Track rsp->gp_seq. */
45
+ unsigned long gp_seq_needed; /* Track furthest future GP request. */
8646 unsigned long completedqs; /* All QSes done for this node. */
8747 unsigned long qsmask; /* CPUs or groups that need to switch in */
8848 /* order for current grace period to proceed.*/
....@@ -96,6 +56,7 @@
9656 /* Initialized from ->qsmaskinitnext at the */
9757 /* beginning of each grace period. */
9858 unsigned long qsmaskinitnext;
59
+ unsigned long ofl_seq; /* CPU-hotplug operation sequence count. */
9960 /* Online CPUs for next grace period. */
10061 unsigned long expmask; /* CPUs or groups that need to check in */
10162 /* to allow the current expedited GP */
....@@ -108,12 +69,14 @@
10869 /* Online CPUs for next expedited GP. */
10970 /* Any CPU that has ever been online will */
11071 /* have its bit set. */
72
+ unsigned long cbovldmask;
73
+ /* CPUs experiencing callback overload. */
11174 unsigned long ffmask; /* Fully functional CPUs. */
11275 unsigned long grpmask; /* Mask to apply to parent qsmask. */
11376 /* Only one bit will be set in this mask. */
114
- int grplo; /* lowest-numbered CPU or group here. */
115
- int grphi; /* highest-numbered CPU or group here. */
116
- u8 grpnum; /* CPU/group number for next level up. */
77
+ int grplo; /* lowest-numbered CPU here. */
78
+ int grphi; /* highest-numbered CPU here. */
79
+ u8 grpnum; /* group number for next level up. */
11780 u8 level; /* root is at level 0. */
11881 bool wait_blkd_tasks;/* Necessary to wait for blocked tasks to */
11982 /* exit RCU read-side critical sections */
....@@ -170,7 +133,7 @@
170133 * are indexed relative to this interval rather than the global CPU ID space.
171134 * This generates the bit for a CPU in node-local masks.
172135 */
173
-#define leaf_node_cpu_bit(rnp, cpu) (1UL << ((cpu) - (rnp)->grplo))
136
+#define leaf_node_cpu_bit(rnp, cpu) (BIT((cpu) - (rnp)->grplo))
174137
175138 /*
176139 * Union to allow "aggregate OR" operation on the need for a quiescent
....@@ -187,20 +150,23 @@
187150 /* Per-CPU data for read-copy update. */
188151 struct rcu_data {
189152 /* 1) quiescent-state and grace-period handling : */
190
- unsigned long gp_seq; /* Track rsp->rcu_gp_seq counter. */
191
- unsigned long gp_seq_needed; /* Track rsp->rcu_gp_seq_needed ctr. */
192
- unsigned long rcu_qs_ctr_snap;/* Snapshot of rcu_qs_ctr to check */
193
- /* for rcu_all_qs() invocations. */
153
+ unsigned long gp_seq; /* Track rsp->gp_seq counter. */
154
+ unsigned long gp_seq_needed; /* Track furthest future GP request. */
194155 union rcu_noqs cpu_no_qs; /* No QSes yet for this CPU. */
195156 bool core_needs_qs; /* Core waits for quiesc state. */
196157 bool beenonline; /* CPU online at least once. */
197158 bool gpwrap; /* Possible ->gp_seq wrap. */
159
+ bool exp_deferred_qs; /* This CPU awaiting a deferred QS? */
160
+ bool cpu_started; /* RCU watching this onlining CPU. */
198161 struct rcu_node *mynode; /* This CPU's leaf of hierarchy */
199162 unsigned long grpmask; /* Mask to apply to leaf qsmask. */
200163 unsigned long ticks_this_gp; /* The number of scheduling-clock */
201164 /* ticks this CPU has handled */
202165 /* during and after the last grace */
203166 /* period it is aware of. */
167
+ struct irq_work defer_qs_iw; /* Obtain later scheduler attention. */
168
+ bool defer_qs_iw_pending; /* Scheduler attention pending? */
169
+ struct work_struct strict_work; /* Schedule readers for strict GPs. */
204170
205171 /* 2) batch handling */
206172 struct rcu_segcblist cblist; /* Segmented callback list, with */
....@@ -208,53 +174,71 @@
208174 /* different grace periods. */
209175 long qlen_last_fqs_check;
210176 /* qlen at last check for QS forcing */
177
+ unsigned long n_cbs_invoked; /* # callbacks invoked since boot. */
211178 unsigned long n_force_qs_snap;
212179 /* did other CPU force QS recently? */
213180 long blimit; /* Upper limit on a processed batch */
214181
215182 /* 3) dynticks interface. */
216
- struct rcu_dynticks *dynticks; /* Shared per-CPU dynticks state. */
217183 int dynticks_snap; /* Per-GP tracking for dynticks. */
218
-
219
- /* 4) reasons this CPU needed to be kicked by force_quiescent_state */
220
- unsigned long dynticks_fqs; /* Kicked due to dynticks idle. */
221
- unsigned long cond_resched_completed;
222
- /* Grace period that needs help */
223
- /* from cond_resched(). */
224
-
225
- /* 5) _rcu_barrier(), OOM callbacks, and expediting. */
226
- struct rcu_head barrier_head;
184
+ long dynticks_nesting; /* Track process nesting level. */
185
+ long dynticks_nmi_nesting; /* Track irq/NMI nesting level. */
186
+ atomic_t dynticks; /* Even value for idle, else odd. */
187
+ bool rcu_need_heavy_qs; /* GP old, so heavy quiescent state! */
188
+ bool rcu_urgent_qs; /* GP old need light quiescent state. */
189
+ bool rcu_forced_tick; /* Forced tick to provide QS. */
190
+ bool rcu_forced_tick_exp; /* ... provide QS to expedited GP. */
227191 #ifdef CONFIG_RCU_FAST_NO_HZ
228
- struct rcu_head oom_head;
192
+ unsigned long last_accelerate; /* Last jiffy CBs were accelerated. */
193
+ unsigned long last_advance_all; /* Last jiffy CBs were all advanced. */
194
+ int tick_nohz_enabled_snap; /* Previously seen value from sysfs. */
229195 #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
196
+
197
+ /* 4) rcu_barrier(), OOM callbacks, and expediting. */
198
+ struct rcu_head barrier_head;
230199 int exp_dynticks_snap; /* Double-check need for IPI. */
231200
232
- /* 6) Callback offloading. */
201
+ /* 5) Callback offloading. */
233202 #ifdef CONFIG_RCU_NOCB_CPU
234
- struct rcu_head *nocb_head; /* CBs waiting for kthread. */
235
- struct rcu_head **nocb_tail;
236
- atomic_long_t nocb_q_count; /* # CBs waiting for nocb */
237
- atomic_long_t nocb_q_count_lazy; /* invocation (all stages). */
238
- struct rcu_head *nocb_follower_head; /* CBs ready to invoke. */
239
- struct rcu_head **nocb_follower_tail;
240
- struct swait_queue_head nocb_wq; /* For nocb kthreads to sleep on. */
241
- struct task_struct *nocb_kthread;
203
+ struct swait_queue_head nocb_cb_wq; /* For nocb kthreads to sleep on. */
204
+ struct task_struct *nocb_gp_kthread;
242205 raw_spinlock_t nocb_lock; /* Guard following pair of fields. */
206
+ atomic_t nocb_lock_contended; /* Contention experienced. */
243207 int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */
244208 struct timer_list nocb_timer; /* Enforce finite deferral. */
209
+ unsigned long nocb_gp_adv_time; /* Last call_rcu() CB adv (jiffies). */
245210
246
- /* The following fields are used by the leader, hence own cacheline. */
247
- struct rcu_head *nocb_gp_head ____cacheline_internodealigned_in_smp;
248
- /* CBs waiting for GP. */
249
- struct rcu_head **nocb_gp_tail;
250
- bool nocb_leader_sleep; /* Is the nocb leader thread asleep? */
251
- struct rcu_data *nocb_next_follower;
252
- /* Next follower in wakeup chain. */
211
+ /* The following fields are used by call_rcu, hence own cacheline. */
212
+ raw_spinlock_t nocb_bypass_lock ____cacheline_internodealigned_in_smp;
213
+ struct rcu_cblist nocb_bypass; /* Lock-contention-bypass CB list. */
214
+ unsigned long nocb_bypass_first; /* Time (jiffies) of first enqueue. */
215
+ unsigned long nocb_nobypass_last; /* Last ->cblist enqueue (jiffies). */
216
+ int nocb_nobypass_count; /* # ->cblist enqueues at ^^^ time. */
253217
254
- /* The following fields are used by the follower, hence new cachline. */
255
- struct rcu_data *nocb_leader ____cacheline_internodealigned_in_smp;
256
- /* Leader CPU takes GP-end wakeups. */
218
+ /* The following fields are used by GP kthread, hence own cacheline. */
219
+ raw_spinlock_t nocb_gp_lock ____cacheline_internodealigned_in_smp;
220
+ struct timer_list nocb_bypass_timer; /* Force nocb_bypass flush. */
221
+ u8 nocb_gp_sleep; /* Is the nocb GP thread asleep? */
222
+ u8 nocb_gp_bypass; /* Found a bypass on last scan? */
223
+ u8 nocb_gp_gp; /* GP to wait for on last scan? */
224
+ unsigned long nocb_gp_seq; /* If so, ->gp_seq to wait for. */
225
+ unsigned long nocb_gp_loops; /* # passes through wait code. */
226
+ struct swait_queue_head nocb_gp_wq; /* For nocb kthreads to sleep on. */
227
+ bool nocb_cb_sleep; /* Is the nocb CB thread asleep? */
228
+ struct task_struct *nocb_cb_kthread;
229
+ struct rcu_data *nocb_next_cb_rdp;
230
+ /* Next rcu_data in wakeup chain. */
231
+
232
+ /* The following fields are used by CB kthread, hence new cacheline. */
233
+ struct rcu_data *nocb_gp_rdp ____cacheline_internodealigned_in_smp;
234
+ /* GP rdp takes GP-end wakeups. */
257235 #endif /* #ifdef CONFIG_RCU_NOCB_CPU */
236
+
237
+ /* 6) RCU priority boosting. */
238
+ struct task_struct *rcu_cpu_kthread_task;
239
+ /* rcuc per-CPU kthread or NULL. */
240
+ unsigned int rcu_cpu_kthread_status;
241
+ char rcu_cpu_has_work;
258242
259243 /* 7) Diagnostic data, including RCU CPU stall warnings. */
260244 unsigned int softirq_snap; /* Snapshot of softirq activity. */
....@@ -266,9 +250,9 @@
266250 short rcu_ofl_gp_flags; /* ->gp_flags at last offline. */
267251 unsigned long rcu_onl_gp_seq; /* ->gp_seq at last online. */
268252 short rcu_onl_gp_flags; /* ->gp_flags at last online. */
253
+ unsigned long last_fqs_resched; /* Time of last rcu_resched(). */
269254
270255 int cpu;
271
- struct rcu_state *rsp;
272256 };
273257
274258 /* Values for nocb_defer_wakeup field in struct rcu_data. */
....@@ -314,8 +298,6 @@
314298 struct rcu_node *level[RCU_NUM_LVLS + 1];
315299 /* Hierarchy levels (+1 to */
316300 /* shut bogus gcc warning) */
317
- struct rcu_data __percpu *rda; /* pointer of percu rcu_data. */
318
- call_rcu_func_t call; /* call_rcu() flavor. */
319301 int ncpus; /* # CPUs seen so far. */
320302
321303 /* The following fields are guarded by the root rcu_node's lock. */
....@@ -323,10 +305,14 @@
323305 u8 boost ____cacheline_internodealigned_in_smp;
324306 /* Subject to priority boost. */
325307 unsigned long gp_seq; /* Grace-period sequence #. */
308
+ unsigned long gp_max; /* Maximum GP duration in */
309
+ /* jiffies. */
326310 struct task_struct *gp_kthread; /* Task for grace periods. */
327311 struct swait_queue_head gp_wq; /* Where GP task waits. */
328312 short gp_flags; /* Commands for GP task. */
329313 short gp_state; /* GP kthread sleep state. */
314
+ unsigned long gp_wake_time; /* Last GP kthread wake. */
315
+ unsigned long gp_wake_seq; /* ->gp_seq at ^^^. */
330316
331317 /* End of fields guarded by root rcu_node's lock. */
332318
....@@ -334,7 +320,7 @@
334320 atomic_t barrier_cpu_count; /* # CPUs waiting on. */
335321 struct completion barrier_completion; /* Wake at barrier end. */
336322 unsigned long barrier_sequence; /* ++ at start and end of */
337
- /* _rcu_barrier(). */
323
+ /* rcu_barrier(). */
338324 /* End of fields guarded by barrier_mutex. */
339325
340326 struct mutex exp_mutex; /* Serialize expedited GP. */
....@@ -343,6 +329,8 @@
343329 atomic_t expedited_need_qs; /* # CPUs left to check in. */
344330 struct swait_queue_head expedited_wq; /* Wait for check-ins. */
345331 int ncpus_snap; /* # CPUs seen last time. */
332
+ u8 cbovld; /* Callback overload now? */
333
+ u8 cbovldnext; /* ^ ^ next time? */
346334
347335 unsigned long jiffies_force_qs; /* Time at which to invoke */
348336 /* force_quiescent_state(). */
....@@ -352,6 +340,8 @@
352340 /* force_quiescent_state(). */
353341 unsigned long gp_start; /* Time at which GP started, */
354342 /* but in jiffies. */
343
+ unsigned long gp_end; /* Time last GP ended, again */
344
+ /* in jiffies. */
355345 unsigned long gp_activity; /* Time of last GP kthread */
356346 /* activity in jiffies. */
357347 unsigned long gp_req_activity; /* Time of last GP request */
....@@ -362,13 +352,10 @@
362352 /* a reluctant CPU. */
363353 unsigned long n_force_qs_gpstart; /* Snapshot of n_force_qs at */
364354 /* GP start. */
365
- unsigned long gp_max; /* Maximum GP duration in */
366
- /* jiffies. */
367355 const char *name; /* Name of structure. */
368356 char abbr; /* Abbreviated name. */
369
- struct list_head flavors; /* List of RCU flavors. */
370357
371
- spinlock_t ofl_lock ____cacheline_internodealigned_in_smp;
358
+ raw_spinlock_t ofl_lock ____cacheline_internodealigned_in_smp;
372359 /* Synchronize offline with */
373360 /* GP pre-initialization. */
374361 };
....@@ -376,6 +363,7 @@
376363 /* Values for rcu_state structure's gp_flags field. */
377364 #define RCU_GP_FLAG_INIT 0x1 /* Need grace-period initialization. */
378365 #define RCU_GP_FLAG_FQS 0x2 /* Need grace-period quiescent-state forcing. */
366
+#define RCU_GP_FLAG_OVLD 0x4 /* Experiencing callback overload. */
379367
380368 /* Values for rcu_state structure's gp_state field. */
381369 #define RCU_GP_IDLE 0 /* Initial state and no GP in progress. */
....@@ -388,113 +376,95 @@
388376 #define RCU_GP_CLEANUP 7 /* Grace-period cleanup started. */
389377 #define RCU_GP_CLEANED 8 /* Grace-period cleanup complete. */
390378
391
-#ifndef RCU_TREE_NONCORE
392
-static const char * const gp_state_names[] = {
393
- "RCU_GP_IDLE",
394
- "RCU_GP_WAIT_GPS",
395
- "RCU_GP_DONE_GPS",
396
- "RCU_GP_ONOFF",
397
- "RCU_GP_INIT",
398
- "RCU_GP_WAIT_FQS",
399
- "RCU_GP_DOING_FQS",
400
- "RCU_GP_CLEANUP",
401
- "RCU_GP_CLEANED",
402
-};
403
-#endif /* #ifndef RCU_TREE_NONCORE */
404
-
405
-extern struct list_head rcu_struct_flavors;
406
-
407
-/* Sequence through rcu_state structures for each RCU flavor. */
408
-#define for_each_rcu_flavor(rsp) \
409
- list_for_each_entry((rsp), &rcu_struct_flavors, flavors)
410
-
411379 /*
412
- * RCU implementation internal declarations:
380
+ * In order to export the rcu_state name to the tracing tools, it
381
+ * needs to be added in the __tracepoint_string section.
382
+ * This requires defining a separate variable tp_<sname>_varname
383
+ * that points to the string being used, and this will allow
384
+ * the tracing userspace tools to be able to decipher the string
385
+ * address to the matching string.
413386 */
414
-extern struct rcu_state rcu_sched_state;
415
-
416
-extern struct rcu_state rcu_bh_state;
417
-
418387 #ifdef CONFIG_PREEMPT_RCU
419
-extern struct rcu_state rcu_preempt_state;
420
-#endif /* #ifdef CONFIG_PREEMPT_RCU */
388
+#define RCU_ABBR 'p'
389
+#define RCU_NAME_RAW "rcu_preempt"
390
+#else /* #ifdef CONFIG_PREEMPT_RCU */
391
+#define RCU_ABBR 's'
392
+#define RCU_NAME_RAW "rcu_sched"
393
+#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
394
+#ifndef CONFIG_TRACING
395
+#define RCU_NAME RCU_NAME_RAW
396
+#else /* #ifdef CONFIG_TRACING */
397
+static char rcu_name[] = RCU_NAME_RAW;
398
+static const char *tp_rcu_varname __used __tracepoint_string = rcu_name;
399
+#define RCU_NAME rcu_name
400
+#endif /* #else #ifdef CONFIG_TRACING */
421401
422
-int rcu_dynticks_snap(struct rcu_dynticks *rdtp);
423
-
424
-#ifdef CONFIG_RCU_BOOST
425
-DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
426
-DECLARE_PER_CPU(int, rcu_cpu_kthread_cpu);
427
-DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
428
-DECLARE_PER_CPU(char, rcu_cpu_has_work);
429
-#endif /* #ifdef CONFIG_RCU_BOOST */
430
-
431
-#ifndef RCU_TREE_NONCORE
432
-
433
-/* Forward declarations for rcutree_plugin.h */
402
+/* Forward declarations for tree_plugin.h */
434403 static void rcu_bootup_announce(void);
435
-static void rcu_preempt_note_context_switch(bool preempt);
404
+static void rcu_qs(void);
436405 static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
437406 #ifdef CONFIG_HOTPLUG_CPU
438407 static bool rcu_preempt_has_tasks(struct rcu_node *rnp);
439408 #endif /* #ifdef CONFIG_HOTPLUG_CPU */
440
-static void rcu_print_detail_task_stall(struct rcu_state *rsp);
441
-static int rcu_print_task_stall(struct rcu_node *rnp);
442409 static int rcu_print_task_exp_stall(struct rcu_node *rnp);
443
-static void rcu_preempt_check_blocked_tasks(struct rcu_state *rsp,
444
- struct rcu_node *rnp);
445
-static void rcu_preempt_check_callbacks(void);
446
-void call_rcu(struct rcu_head *head, rcu_callback_t func);
447
-static void __init __rcu_init_preempt(void);
448
-static void dump_blkd_tasks(struct rcu_state *rsp, struct rcu_node *rnp,
449
- int ncheck);
410
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
411
+static void rcu_flavor_sched_clock_irq(int user);
412
+static void dump_blkd_tasks(struct rcu_node *rnp, int ncheck);
450413 static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
451414 static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
452
-static void invoke_rcu_callbacks_kthread(void);
453415 static bool rcu_is_callbacks_kthread(void);
454
-#ifdef CONFIG_RCU_BOOST
455
-static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
456
- struct rcu_node *rnp);
457
-#endif /* #ifdef CONFIG_RCU_BOOST */
416
+static void rcu_cpu_kthread_setup(unsigned int cpu);
458417 static void __init rcu_spawn_boost_kthreads(void);
459418 static void rcu_prepare_kthreads(int cpu);
460419 static void rcu_cleanup_after_idle(void);
461420 static void rcu_prepare_for_idle(void);
462
-static void rcu_idle_count_callbacks_posted(void);
463421 static bool rcu_preempt_has_tasks(struct rcu_node *rnp);
464
-static void print_cpu_stall_info_begin(void);
465
-static void print_cpu_stall_info(struct rcu_state *rsp, int cpu);
466
-static void print_cpu_stall_info_end(void);
422
+static bool rcu_preempt_need_deferred_qs(struct task_struct *t);
423
+static void rcu_preempt_deferred_qs(struct task_struct *t);
467424 static void zero_cpu_stall_ticks(struct rcu_data *rdp);
468
-static void increment_cpu_stall_ticks(void);
469
-static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu);
470425 static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp);
471426 static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq);
472427 static void rcu_init_one_nocb(struct rcu_node *rnp);
473
-static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
474
- bool lazy, unsigned long flags);
475
-static bool rcu_nocb_adopt_orphan_cbs(struct rcu_data *my_rdp,
476
- struct rcu_data *rdp,
477
- unsigned long flags);
428
+static bool rcu_nocb_flush_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
429
+ unsigned long j);
430
+static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
431
+ bool *was_alldone, unsigned long flags);
432
+static void __call_rcu_nocb_wake(struct rcu_data *rdp, bool was_empty,
433
+ unsigned long flags);
478434 static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp);
479435 static void do_nocb_deferred_wakeup(struct rcu_data *rdp);
480436 static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp);
481
-static void rcu_spawn_all_nocb_kthreads(int cpu);
437
+static void rcu_spawn_cpu_nocb_kthread(int cpu);
482438 static void __init rcu_spawn_nocb_kthreads(void);
439
+static void show_rcu_nocb_state(struct rcu_data *rdp);
440
+static void rcu_nocb_lock(struct rcu_data *rdp);
441
+static void rcu_nocb_unlock(struct rcu_data *rdp);
442
+static void rcu_nocb_unlock_irqrestore(struct rcu_data *rdp,
443
+ unsigned long flags);
444
+static void rcu_lockdep_assert_cblist_protected(struct rcu_data *rdp);
483445 #ifdef CONFIG_RCU_NOCB_CPU
484
-static void __init rcu_organize_nocb_kthreads(struct rcu_state *rsp);
485
-#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
486
-static bool init_nocb_callback_list(struct rcu_data *rdp);
446
+static void __init rcu_organize_nocb_kthreads(void);
447
+#define rcu_nocb_lock_irqsave(rdp, flags) \
448
+do { \
449
+ if (!rcu_segcblist_is_offloaded(&(rdp)->cblist)) \
450
+ local_irq_save(flags); \
451
+ else \
452
+ raw_spin_lock_irqsave(&(rdp)->nocb_lock, (flags)); \
453
+} while (0)
454
+#else /* #ifdef CONFIG_RCU_NOCB_CPU */
455
+#define rcu_nocb_lock_irqsave(rdp, flags) local_irq_save(flags)
456
+#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */
457
+
487458 static void rcu_bind_gp_kthread(void);
488
-static bool rcu_nohz_full_cpu(struct rcu_state *rsp);
459
+static bool rcu_nohz_full_cpu(void);
489460 static void rcu_dynticks_task_enter(void);
490461 static void rcu_dynticks_task_exit(void);
462
+static void rcu_dynticks_task_trace_enter(void);
463
+static void rcu_dynticks_task_trace_exit(void);
491464
492
-#ifdef CONFIG_SRCU
493
-void srcu_online_cpu(unsigned int cpu);
494
-void srcu_offline_cpu(unsigned int cpu);
495
-#else /* #ifdef CONFIG_SRCU */
496
-void srcu_online_cpu(unsigned int cpu) { }
497
-void srcu_offline_cpu(unsigned int cpu) { }
498
-#endif /* #else #ifdef CONFIG_SRCU */
499
-
500
-#endif /* #ifndef RCU_TREE_NONCORE */
465
+/* Forward declarations for tree_stall.h */
466
+static void record_gp_stall_check_time(void);
467
+static void rcu_iw_handler(struct irq_work *iwp);
468
+static void check_cpu_stall(struct rcu_data *rdp);
469
+static void rcu_check_gp_start_stall(struct rcu_node *rnp, struct rcu_data *rdp,
470
+ const unsigned long gpssdelay);