Commit | Line | Data |
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8bf05ed3 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
8704baab | 2 | /* |
4e88ec4a | 3 | * Read-Copy Update module-based scalability-test facility |
8704baab | 4 | * |
8704baab PM |
5 | * Copyright (C) IBM Corporation, 2015 |
6 | * | |
8bf05ed3 | 7 | * Authors: Paul E. McKenney <paulmck@linux.ibm.com> |
8704baab | 8 | */ |
60500037 PM |
9 | |
10 | #define pr_fmt(fmt) fmt | |
11 | ||
8704baab PM |
12 | #include <linux/types.h> |
13 | #include <linux/kernel.h> | |
14 | #include <linux/init.h> | |
12af6603 | 15 | #include <linux/mm.h> |
8704baab PM |
16 | #include <linux/module.h> |
17 | #include <linux/kthread.h> | |
18 | #include <linux/err.h> | |
19 | #include <linux/spinlock.h> | |
20 | #include <linux/smp.h> | |
21 | #include <linux/rcupdate.h> | |
22 | #include <linux/interrupt.h> | |
23 | #include <linux/sched.h> | |
ae7e81c0 | 24 | #include <uapi/linux/sched/types.h> |
8704baab PM |
25 | #include <linux/atomic.h> |
26 | #include <linux/bitops.h> | |
27 | #include <linux/completion.h> | |
28 | #include <linux/moduleparam.h> | |
29 | #include <linux/percpu.h> | |
30 | #include <linux/notifier.h> | |
31 | #include <linux/reboot.h> | |
32 | #include <linux/freezer.h> | |
33 | #include <linux/cpu.h> | |
34 | #include <linux/delay.h> | |
35 | #include <linux/stat.h> | |
36 | #include <linux/srcu.h> | |
37 | #include <linux/slab.h> | |
38 | #include <asm/byteorder.h> | |
39 | #include <linux/torture.h> | |
40 | #include <linux/vmalloc.h> | |
899f317e | 41 | #include <linux/rcupdate_trace.h> |
8704baab | 42 | |
25c36329 PM |
43 | #include "rcu.h" |
44 | ||
8704baab | 45 | MODULE_LICENSE("GPL"); |
8bf05ed3 | 46 | MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>"); |
8704baab | 47 | |
4e88ec4a PM |
48 | #define SCALE_FLAG "-scale:" |
49 | #define SCALEOUT_STRING(s) \ | |
50 | pr_alert("%s" SCALE_FLAG " %s\n", scale_type, s) | |
51 | #define VERBOSE_SCALEOUT_STRING(s) \ | |
52 | do { if (verbose) pr_alert("%s" SCALE_FLAG " %s\n", scale_type, s); } while (0) | |
86e7ed1b LZ |
53 | #define SCALEOUT_ERRSTRING(s) \ |
54 | pr_alert("%s" SCALE_FLAG "!!! %s\n", scale_type, s) | |
8704baab | 55 | |
85ba6bfe PM |
56 | /* |
57 | * The intended use cases for the nreaders and nwriters module parameters | |
58 | * are as follows: | |
59 | * | |
60 | * 1. Specify only the nr_cpus kernel boot parameter. This will | |
61 | * set both nreaders and nwriters to the value specified by | |
62 | * nr_cpus for a mixed reader/writer test. | |
63 | * | |
64 | * 2. Specify the nr_cpus kernel boot parameter, but set | |
4e88ec4a | 65 | * rcuscale.nreaders to zero. This will set nwriters to the |
85ba6bfe PM |
66 | * value specified by nr_cpus for an update-only test. |
67 | * | |
68 | * 3. Specify the nr_cpus kernel boot parameter, but set | |
4e88ec4a | 69 | * rcuscale.nwriters to zero. This will set nreaders to the |
85ba6bfe PM |
70 | * value specified by nr_cpus for a read-only test. |
71 | * | |
72 | * Various other use cases may of course be specified. | |
708cda31 PM |
73 | * |
74 | * Note that this test's readers are intended only as a test load for | |
4e88ec4a | 75 | * the writers. The reader scalability statistics will be overly |
708cda31 PM |
76 | * pessimistic due to the per-critical-section interrupt disabling, |
77 | * test-end checks, and the pair of calls through pointers. | |
85ba6bfe PM |
78 | */ |
79 | ||
e838a7d6 | 80 | #ifdef MODULE |
4e88ec4a | 81 | # define RCUSCALE_SHUTDOWN 0 |
e838a7d6 | 82 | #else |
4e88ec4a | 83 | # define RCUSCALE_SHUTDOWN 1 |
e838a7d6 PM |
84 | #endif |
85 | ||
881ed593 PM |
86 | torture_param(bool, gp_async, false, "Use asynchronous GP wait primitives"); |
87 | torture_param(int, gp_async_max, 1000, "Max # outstanding waits per reader"); | |
af06d4f7 | 88 | torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); |
df37e66b | 89 | torture_param(int, holdoff, 10, "Holdoff time before test start (s)"); |
85ba6bfe | 90 | torture_param(int, nreaders, -1, "Number of RCU reader threads"); |
8704baab | 91 | torture_param(int, nwriters, -1, "Number of RCU updater threads"); |
4e88ec4a PM |
92 | torture_param(bool, shutdown, RCUSCALE_SHUTDOWN, |
93 | "Shutdown at end of scalability tests."); | |
90127d60 | 94 | torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); |
820687a7 | 95 | torture_param(int, writer_holdoff, 0, "Holdoff (us) between GPs, zero to disable"); |
4e88ec4a | 96 | torture_param(int, kfree_rcu_test, 0, "Do we run a kfree_rcu() scale test?"); |
f87dc808 | 97 | torture_param(int, kfree_mult, 1, "Multiple of kfree_obj size to allocate."); |
8704baab | 98 | |
4e88ec4a PM |
99 | static char *scale_type = "rcu"; |
100 | module_param(scale_type, charp, 0444); | |
101 | MODULE_PARM_DESC(scale_type, "Type of RCU to scalability-test (rcu, srcu, ...)"); | |
8704baab PM |
102 | |
103 | static int nrealreaders; | |
104 | static int nrealwriters; | |
105 | static struct task_struct **writer_tasks; | |
106 | static struct task_struct **reader_tasks; | |
107 | static struct task_struct *shutdown_task; | |
108 | ||
109 | static u64 **writer_durations; | |
110 | static int *writer_n_durations; | |
4e88ec4a PM |
111 | static atomic_t n_rcu_scale_reader_started; |
112 | static atomic_t n_rcu_scale_writer_started; | |
113 | static atomic_t n_rcu_scale_writer_finished; | |
8704baab | 114 | static wait_queue_head_t shutdown_wq; |
4e88ec4a PM |
115 | static u64 t_rcu_scale_writer_started; |
116 | static u64 t_rcu_scale_writer_finished; | |
e6e78b00 JFG |
117 | static unsigned long b_rcu_gp_test_started; |
118 | static unsigned long b_rcu_gp_test_finished; | |
881ed593 | 119 | static DEFINE_PER_CPU(atomic_t, n_async_inflight); |
8704baab | 120 | |
8704baab PM |
121 | #define MAX_MEAS 10000 |
122 | #define MIN_MEAS 100 | |
123 | ||
8704baab PM |
124 | /* |
125 | * Operations vector for selecting different types of tests. | |
126 | */ | |
127 | ||
4e88ec4a | 128 | struct rcu_scale_ops { |
8704baab PM |
129 | int ptype; |
130 | void (*init)(void); | |
131 | void (*cleanup)(void); | |
132 | int (*readlock)(void); | |
133 | void (*readunlock)(int idx); | |
17ef2fe9 | 134 | unsigned long (*get_gp_seq)(void); |
d7219312 | 135 | unsigned long (*gp_diff)(unsigned long new, unsigned long old); |
8704baab | 136 | unsigned long (*exp_completed)(void); |
881ed593 PM |
137 | void (*async)(struct rcu_head *head, rcu_callback_t func); |
138 | void (*gp_barrier)(void); | |
8704baab PM |
139 | void (*sync)(void); |
140 | void (*exp_sync)(void); | |
141 | const char *name; | |
142 | }; | |
143 | ||
4e88ec4a | 144 | static struct rcu_scale_ops *cur_ops; |
8704baab PM |
145 | |
146 | /* | |
4e88ec4a | 147 | * Definitions for rcu scalability testing. |
8704baab PM |
148 | */ |
149 | ||
4e88ec4a | 150 | static int rcu_scale_read_lock(void) __acquires(RCU) |
8704baab PM |
151 | { |
152 | rcu_read_lock(); | |
153 | return 0; | |
154 | } | |
155 | ||
4e88ec4a | 156 | static void rcu_scale_read_unlock(int idx) __releases(RCU) |
8704baab PM |
157 | { |
158 | rcu_read_unlock(); | |
159 | } | |
160 | ||
161 | static unsigned long __maybe_unused rcu_no_completed(void) | |
162 | { | |
163 | return 0; | |
164 | } | |
165 | ||
4e88ec4a | 166 | static void rcu_sync_scale_init(void) |
8704baab PM |
167 | { |
168 | } | |
169 | ||
4e88ec4a | 170 | static struct rcu_scale_ops rcu_ops = { |
8704baab | 171 | .ptype = RCU_FLAVOR, |
4e88ec4a PM |
172 | .init = rcu_sync_scale_init, |
173 | .readlock = rcu_scale_read_lock, | |
174 | .readunlock = rcu_scale_read_unlock, | |
17ef2fe9 | 175 | .get_gp_seq = rcu_get_gp_seq, |
d7219312 | 176 | .gp_diff = rcu_seq_diff, |
8704baab | 177 | .exp_completed = rcu_exp_batches_completed, |
881ed593 PM |
178 | .async = call_rcu, |
179 | .gp_barrier = rcu_barrier, | |
8704baab PM |
180 | .sync = synchronize_rcu, |
181 | .exp_sync = synchronize_rcu_expedited, | |
182 | .name = "rcu" | |
183 | }; | |
184 | ||
8704baab | 185 | /* |
4e88ec4a | 186 | * Definitions for srcu scalability testing. |
8704baab PM |
187 | */ |
188 | ||
4e88ec4a PM |
189 | DEFINE_STATIC_SRCU(srcu_ctl_scale); |
190 | static struct srcu_struct *srcu_ctlp = &srcu_ctl_scale; | |
8704baab | 191 | |
4e88ec4a | 192 | static int srcu_scale_read_lock(void) __acquires(srcu_ctlp) |
8704baab PM |
193 | { |
194 | return srcu_read_lock(srcu_ctlp); | |
195 | } | |
196 | ||
4e88ec4a | 197 | static void srcu_scale_read_unlock(int idx) __releases(srcu_ctlp) |
8704baab PM |
198 | { |
199 | srcu_read_unlock(srcu_ctlp, idx); | |
200 | } | |
201 | ||
4e88ec4a | 202 | static unsigned long srcu_scale_completed(void) |
8704baab PM |
203 | { |
204 | return srcu_batches_completed(srcu_ctlp); | |
205 | } | |
206 | ||
881ed593 PM |
207 | static void srcu_call_rcu(struct rcu_head *head, rcu_callback_t func) |
208 | { | |
209 | call_srcu(srcu_ctlp, head, func); | |
210 | } | |
211 | ||
212 | static void srcu_rcu_barrier(void) | |
213 | { | |
214 | srcu_barrier(srcu_ctlp); | |
215 | } | |
216 | ||
4e88ec4a | 217 | static void srcu_scale_synchronize(void) |
8704baab PM |
218 | { |
219 | synchronize_srcu(srcu_ctlp); | |
220 | } | |
221 | ||
4e88ec4a | 222 | static void srcu_scale_synchronize_expedited(void) |
8704baab PM |
223 | { |
224 | synchronize_srcu_expedited(srcu_ctlp); | |
225 | } | |
226 | ||
4e88ec4a | 227 | static struct rcu_scale_ops srcu_ops = { |
8704baab | 228 | .ptype = SRCU_FLAVOR, |
4e88ec4a PM |
229 | .init = rcu_sync_scale_init, |
230 | .readlock = srcu_scale_read_lock, | |
231 | .readunlock = srcu_scale_read_unlock, | |
232 | .get_gp_seq = srcu_scale_completed, | |
d7219312 | 233 | .gp_diff = rcu_seq_diff, |
4e88ec4a | 234 | .exp_completed = srcu_scale_completed, |
881ed593 PM |
235 | .async = srcu_call_rcu, |
236 | .gp_barrier = srcu_rcu_barrier, | |
4e88ec4a PM |
237 | .sync = srcu_scale_synchronize, |
238 | .exp_sync = srcu_scale_synchronize_expedited, | |
8704baab PM |
239 | .name = "srcu" |
240 | }; | |
241 | ||
f60cb4d4 PM |
242 | static struct srcu_struct srcud; |
243 | ||
4e88ec4a | 244 | static void srcu_sync_scale_init(void) |
f60cb4d4 PM |
245 | { |
246 | srcu_ctlp = &srcud; | |
247 | init_srcu_struct(srcu_ctlp); | |
248 | } | |
249 | ||
4e88ec4a | 250 | static void srcu_sync_scale_cleanup(void) |
f60cb4d4 PM |
251 | { |
252 | cleanup_srcu_struct(srcu_ctlp); | |
253 | } | |
254 | ||
4e88ec4a | 255 | static struct rcu_scale_ops srcud_ops = { |
f60cb4d4 | 256 | .ptype = SRCU_FLAVOR, |
4e88ec4a PM |
257 | .init = srcu_sync_scale_init, |
258 | .cleanup = srcu_sync_scale_cleanup, | |
259 | .readlock = srcu_scale_read_lock, | |
260 | .readunlock = srcu_scale_read_unlock, | |
261 | .get_gp_seq = srcu_scale_completed, | |
d7219312 | 262 | .gp_diff = rcu_seq_diff, |
4e88ec4a | 263 | .exp_completed = srcu_scale_completed, |
f60cb4d4 PM |
264 | .async = srcu_call_rcu, |
265 | .gp_barrier = srcu_rcu_barrier, | |
4e88ec4a PM |
266 | .sync = srcu_scale_synchronize, |
267 | .exp_sync = srcu_scale_synchronize_expedited, | |
f60cb4d4 PM |
268 | .name = "srcud" |
269 | }; | |
270 | ||
4df002d9 PM |
271 | #ifdef CONFIG_TASKS_RCU |
272 | ||
8704baab | 273 | /* |
4e88ec4a | 274 | * Definitions for RCU-tasks scalability testing. |
8704baab PM |
275 | */ |
276 | ||
4e88ec4a | 277 | static int tasks_scale_read_lock(void) |
8704baab PM |
278 | { |
279 | return 0; | |
280 | } | |
281 | ||
4e88ec4a | 282 | static void tasks_scale_read_unlock(int idx) |
8704baab PM |
283 | { |
284 | } | |
285 | ||
4e88ec4a | 286 | static struct rcu_scale_ops tasks_ops = { |
8704baab | 287 | .ptype = RCU_TASKS_FLAVOR, |
4e88ec4a PM |
288 | .init = rcu_sync_scale_init, |
289 | .readlock = tasks_scale_read_lock, | |
290 | .readunlock = tasks_scale_read_unlock, | |
17ef2fe9 | 291 | .get_gp_seq = rcu_no_completed, |
d7219312 | 292 | .gp_diff = rcu_seq_diff, |
881ed593 PM |
293 | .async = call_rcu_tasks, |
294 | .gp_barrier = rcu_barrier_tasks, | |
8704baab PM |
295 | .sync = synchronize_rcu_tasks, |
296 | .exp_sync = synchronize_rcu_tasks, | |
297 | .name = "tasks" | |
298 | }; | |
299 | ||
4df002d9 PM |
300 | #define TASKS_OPS &tasks_ops, |
301 | ||
302 | #else // #ifdef CONFIG_TASKS_RCU | |
303 | ||
304 | #define TASKS_OPS | |
305 | ||
306 | #endif // #else // #ifdef CONFIG_TASKS_RCU | |
307 | ||
5ce027f4 PM |
308 | #ifdef CONFIG_TASKS_TRACE_RCU |
309 | ||
899f317e PM |
310 | /* |
311 | * Definitions for RCU-tasks-trace scalability testing. | |
312 | */ | |
313 | ||
314 | static int tasks_trace_scale_read_lock(void) | |
315 | { | |
316 | rcu_read_lock_trace(); | |
317 | return 0; | |
318 | } | |
319 | ||
320 | static void tasks_trace_scale_read_unlock(int idx) | |
321 | { | |
322 | rcu_read_unlock_trace(); | |
323 | } | |
324 | ||
325 | static struct rcu_scale_ops tasks_tracing_ops = { | |
326 | .ptype = RCU_TASKS_FLAVOR, | |
327 | .init = rcu_sync_scale_init, | |
328 | .readlock = tasks_trace_scale_read_lock, | |
329 | .readunlock = tasks_trace_scale_read_unlock, | |
330 | .get_gp_seq = rcu_no_completed, | |
331 | .gp_diff = rcu_seq_diff, | |
332 | .async = call_rcu_tasks_trace, | |
333 | .gp_barrier = rcu_barrier_tasks_trace, | |
334 | .sync = synchronize_rcu_tasks_trace, | |
335 | .exp_sync = synchronize_rcu_tasks_trace, | |
336 | .name = "tasks-tracing" | |
337 | }; | |
338 | ||
5ce027f4 PM |
339 | #define TASKS_TRACING_OPS &tasks_tracing_ops, |
340 | ||
341 | #else // #ifdef CONFIG_TASKS_TRACE_RCU | |
342 | ||
343 | #define TASKS_TRACING_OPS | |
344 | ||
345 | #endif // #else // #ifdef CONFIG_TASKS_TRACE_RCU | |
346 | ||
4e88ec4a | 347 | static unsigned long rcuscale_seq_diff(unsigned long new, unsigned long old) |
d7219312 PM |
348 | { |
349 | if (!cur_ops->gp_diff) | |
350 | return new - old; | |
351 | return cur_ops->gp_diff(new, old); | |
352 | } | |
353 | ||
8704baab | 354 | /* |
4e88ec4a | 355 | * If scalability tests complete, wait for shutdown to commence. |
8704baab | 356 | */ |
4e88ec4a | 357 | static void rcu_scale_wait_shutdown(void) |
8704baab | 358 | { |
cee43939 | 359 | cond_resched_tasks_rcu_qs(); |
4e88ec4a | 360 | if (atomic_read(&n_rcu_scale_writer_finished) < nrealwriters) |
8704baab PM |
361 | return; |
362 | while (!torture_must_stop()) | |
363 | schedule_timeout_uninterruptible(1); | |
364 | } | |
365 | ||
366 | /* | |
4e88ec4a PM |
367 | * RCU scalability reader kthread. Repeatedly does empty RCU read-side |
368 | * critical section, minimizing update-side interference. However, the | |
369 | * point of this test is not to evaluate reader scalability, but instead | |
370 | * to serve as a test load for update-side scalability testing. | |
8704baab PM |
371 | */ |
372 | static int | |
4e88ec4a | 373 | rcu_scale_reader(void *arg) |
8704baab PM |
374 | { |
375 | unsigned long flags; | |
376 | int idx; | |
6b558c4c | 377 | long me = (long)arg; |
8704baab | 378 | |
4e88ec4a | 379 | VERBOSE_SCALEOUT_STRING("rcu_scale_reader task started"); |
6b558c4c | 380 | set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); |
8704baab | 381 | set_user_nice(current, MAX_NICE); |
4e88ec4a | 382 | atomic_inc(&n_rcu_scale_reader_started); |
8704baab PM |
383 | |
384 | do { | |
385 | local_irq_save(flags); | |
386 | idx = cur_ops->readlock(); | |
387 | cur_ops->readunlock(idx); | |
388 | local_irq_restore(flags); | |
4e88ec4a | 389 | rcu_scale_wait_shutdown(); |
8704baab | 390 | } while (!torture_must_stop()); |
4e88ec4a | 391 | torture_kthread_stopping("rcu_scale_reader"); |
8704baab PM |
392 | return 0; |
393 | } | |
394 | ||
881ed593 | 395 | /* |
4e88ec4a | 396 | * Callback function for asynchronous grace periods from rcu_scale_writer(). |
881ed593 | 397 | */ |
4e88ec4a | 398 | static void rcu_scale_async_cb(struct rcu_head *rhp) |
881ed593 PM |
399 | { |
400 | atomic_dec(this_cpu_ptr(&n_async_inflight)); | |
401 | kfree(rhp); | |
402 | } | |
403 | ||
8704baab | 404 | /* |
4e88ec4a | 405 | * RCU scale writer kthread. Repeatedly does a grace period. |
8704baab PM |
406 | */ |
407 | static int | |
4e88ec4a | 408 | rcu_scale_writer(void *arg) |
8704baab PM |
409 | { |
410 | int i = 0; | |
411 | int i_max; | |
412 | long me = (long)arg; | |
881ed593 | 413 | struct rcu_head *rhp = NULL; |
8704baab PM |
414 | bool started = false, done = false, alldone = false; |
415 | u64 t; | |
416 | u64 *wdp; | |
417 | u64 *wdpp = writer_durations[me]; | |
418 | ||
4e88ec4a | 419 | VERBOSE_SCALEOUT_STRING("rcu_scale_writer task started"); |
8704baab | 420 | WARN_ON(!wdpp); |
6b558c4c | 421 | set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); |
b1433395 | 422 | sched_set_fifo_low(current); |
df37e66b PM |
423 | |
424 | if (holdoff) | |
425 | schedule_timeout_uninterruptible(holdoff * HZ); | |
426 | ||
77e9752c JFG |
427 | /* |
428 | * Wait until rcu_end_inkernel_boot() is called for normal GP tests | |
429 | * so that RCU is not always expedited for normal GP tests. | |
430 | * The system_state test is approximate, but works well in practice. | |
431 | */ | |
432 | while (!gp_exp && system_state != SYSTEM_RUNNING) | |
433 | schedule_timeout_uninterruptible(1); | |
434 | ||
8704baab | 435 | t = ktime_get_mono_fast_ns(); |
4e88ec4a PM |
436 | if (atomic_inc_return(&n_rcu_scale_writer_started) >= nrealwriters) { |
437 | t_rcu_scale_writer_started = t; | |
8704baab | 438 | if (gp_exp) { |
e6e78b00 | 439 | b_rcu_gp_test_started = |
8704baab PM |
440 | cur_ops->exp_completed() / 2; |
441 | } else { | |
e6e78b00 | 442 | b_rcu_gp_test_started = cur_ops->get_gp_seq(); |
8704baab PM |
443 | } |
444 | } | |
445 | ||
446 | do { | |
820687a7 PM |
447 | if (writer_holdoff) |
448 | udelay(writer_holdoff); | |
8704baab PM |
449 | wdp = &wdpp[i]; |
450 | *wdp = ktime_get_mono_fast_ns(); | |
881ed593 PM |
451 | if (gp_async) { |
452 | retry: | |
453 | if (!rhp) | |
454 | rhp = kmalloc(sizeof(*rhp), GFP_KERNEL); | |
455 | if (rhp && atomic_read(this_cpu_ptr(&n_async_inflight)) < gp_async_max) { | |
881ed593 | 456 | atomic_inc(this_cpu_ptr(&n_async_inflight)); |
4e88ec4a | 457 | cur_ops->async(rhp, rcu_scale_async_cb); |
881ed593 PM |
458 | rhp = NULL; |
459 | } else if (!kthread_should_stop()) { | |
881ed593 PM |
460 | cur_ops->gp_barrier(); |
461 | goto retry; | |
462 | } else { | |
463 | kfree(rhp); /* Because we are stopping. */ | |
464 | } | |
465 | } else if (gp_exp) { | |
8704baab PM |
466 | cur_ops->exp_sync(); |
467 | } else { | |
8704baab PM |
468 | cur_ops->sync(); |
469 | } | |
8704baab PM |
470 | t = ktime_get_mono_fast_ns(); |
471 | *wdp = t - *wdp; | |
472 | i_max = i; | |
473 | if (!started && | |
4e88ec4a | 474 | atomic_read(&n_rcu_scale_writer_started) >= nrealwriters) |
8704baab PM |
475 | started = true; |
476 | if (!done && i >= MIN_MEAS) { | |
477 | done = true; | |
b1433395 | 478 | sched_set_normal(current, 0); |
4e88ec4a PM |
479 | pr_alert("%s%s rcu_scale_writer %ld has %d measurements\n", |
480 | scale_type, SCALE_FLAG, me, MIN_MEAS); | |
481 | if (atomic_inc_return(&n_rcu_scale_writer_finished) >= | |
8704baab | 482 | nrealwriters) { |
620316e5 | 483 | schedule_timeout_interruptible(10); |
ac2bb275 | 484 | rcu_ftrace_dump(DUMP_ALL); |
4e88ec4a PM |
485 | SCALEOUT_STRING("Test complete"); |
486 | t_rcu_scale_writer_finished = t; | |
8704baab | 487 | if (gp_exp) { |
e6e78b00 | 488 | b_rcu_gp_test_finished = |
8704baab PM |
489 | cur_ops->exp_completed() / 2; |
490 | } else { | |
e6e78b00 | 491 | b_rcu_gp_test_finished = |
17ef2fe9 | 492 | cur_ops->get_gp_seq(); |
8704baab | 493 | } |
e6fb1fc1 AS |
494 | if (shutdown) { |
495 | smp_mb(); /* Assign before wake. */ | |
496 | wake_up(&shutdown_wq); | |
497 | } | |
8704baab PM |
498 | } |
499 | } | |
500 | if (done && !alldone && | |
4e88ec4a | 501 | atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters) |
8704baab PM |
502 | alldone = true; |
503 | if (started && !alldone && i < MAX_MEAS - 1) | |
504 | i++; | |
4e88ec4a | 505 | rcu_scale_wait_shutdown(); |
8704baab | 506 | } while (!torture_must_stop()); |
881ed593 | 507 | if (gp_async) { |
881ed593 PM |
508 | cur_ops->gp_barrier(); |
509 | } | |
811192c5 | 510 | writer_n_durations[me] = i_max + 1; |
4e88ec4a | 511 | torture_kthread_stopping("rcu_scale_writer"); |
8704baab PM |
512 | return 0; |
513 | } | |
514 | ||
96221795 | 515 | static void |
4e88ec4a | 516 | rcu_scale_print_module_parms(struct rcu_scale_ops *cur_ops, const char *tag) |
8704baab | 517 | { |
4e88ec4a | 518 | pr_alert("%s" SCALE_FLAG |
8704baab | 519 | "--- %s: nreaders=%d nwriters=%d verbose=%d shutdown=%d\n", |
4e88ec4a | 520 | scale_type, tag, nrealreaders, nrealwriters, verbose, shutdown); |
8704baab PM |
521 | } |
522 | ||
523 | static void | |
4e88ec4a | 524 | rcu_scale_cleanup(void) |
8704baab PM |
525 | { |
526 | int i; | |
527 | int j; | |
528 | int ngps = 0; | |
529 | u64 *wdp; | |
530 | u64 *wdpp; | |
531 | ||
9683937d PM |
532 | /* |
533 | * Would like warning at start, but everything is expedited | |
534 | * during the mid-boot phase, so have to wait till the end. | |
535 | */ | |
536 | if (rcu_gp_is_expedited() && !rcu_gp_is_normal() && !gp_exp) | |
86e7ed1b | 537 | SCALEOUT_ERRSTRING("All grace periods expedited, no normal ones to measure!"); |
9683937d | 538 | if (rcu_gp_is_normal() && gp_exp) |
86e7ed1b | 539 | SCALEOUT_ERRSTRING("All grace periods normal, no expedited ones to measure!"); |
881ed593 | 540 | if (gp_exp && gp_async) |
86e7ed1b | 541 | SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!"); |
9683937d | 542 | |
8704baab PM |
543 | if (torture_cleanup_begin()) |
544 | return; | |
ad092c02 PM |
545 | if (!cur_ops) { |
546 | torture_cleanup_end(); | |
547 | return; | |
548 | } | |
8704baab PM |
549 | |
550 | if (reader_tasks) { | |
551 | for (i = 0; i < nrealreaders; i++) | |
4e88ec4a | 552 | torture_stop_kthread(rcu_scale_reader, |
8704baab PM |
553 | reader_tasks[i]); |
554 | kfree(reader_tasks); | |
555 | } | |
556 | ||
557 | if (writer_tasks) { | |
558 | for (i = 0; i < nrealwriters; i++) { | |
4e88ec4a | 559 | torture_stop_kthread(rcu_scale_writer, |
8704baab PM |
560 | writer_tasks[i]); |
561 | if (!writer_n_durations) | |
562 | continue; | |
563 | j = writer_n_durations[i]; | |
564 | pr_alert("%s%s writer %d gps: %d\n", | |
4e88ec4a | 565 | scale_type, SCALE_FLAG, i, j); |
8704baab PM |
566 | ngps += j; |
567 | } | |
568 | pr_alert("%s%s start: %llu end: %llu duration: %llu gps: %d batches: %ld\n", | |
4e88ec4a PM |
569 | scale_type, SCALE_FLAG, |
570 | t_rcu_scale_writer_started, t_rcu_scale_writer_finished, | |
571 | t_rcu_scale_writer_finished - | |
572 | t_rcu_scale_writer_started, | |
8704baab | 573 | ngps, |
4e88ec4a PM |
574 | rcuscale_seq_diff(b_rcu_gp_test_finished, |
575 | b_rcu_gp_test_started)); | |
8704baab PM |
576 | for (i = 0; i < nrealwriters; i++) { |
577 | if (!writer_durations) | |
578 | break; | |
579 | if (!writer_n_durations) | |
580 | continue; | |
581 | wdpp = writer_durations[i]; | |
582 | if (!wdpp) | |
583 | continue; | |
811192c5 | 584 | for (j = 0; j < writer_n_durations[i]; j++) { |
8704baab PM |
585 | wdp = &wdpp[j]; |
586 | pr_alert("%s%s %4d writer-duration: %5d %llu\n", | |
4e88ec4a | 587 | scale_type, SCALE_FLAG, |
8704baab PM |
588 | i, j, *wdp); |
589 | if (j % 100 == 0) | |
590 | schedule_timeout_uninterruptible(1); | |
591 | } | |
592 | kfree(writer_durations[i]); | |
593 | } | |
594 | kfree(writer_tasks); | |
595 | kfree(writer_durations); | |
596 | kfree(writer_n_durations); | |
597 | } | |
598 | ||
620d2460 | 599 | /* Do torture-type-specific cleanup operations. */ |
8704baab PM |
600 | if (cur_ops->cleanup != NULL) |
601 | cur_ops->cleanup(); | |
602 | ||
603 | torture_cleanup_end(); | |
604 | } | |
605 | ||
606 | /* | |
607 | * Return the number if non-negative. If -1, the number of CPUs. | |
608 | * If less than -1, that much less than the number of CPUs, but | |
609 | * at least one. | |
610 | */ | |
611 | static int compute_real(int n) | |
612 | { | |
613 | int nr; | |
614 | ||
615 | if (n >= 0) { | |
616 | nr = n; | |
617 | } else { | |
618 | nr = num_online_cpus() + 1 + n; | |
619 | if (nr <= 0) | |
620 | nr = 1; | |
621 | } | |
622 | return nr; | |
623 | } | |
624 | ||
625 | /* | |
4e88ec4a | 626 | * RCU scalability shutdown kthread. Just waits to be awakened, then shuts |
8704baab PM |
627 | * down system. |
628 | */ | |
629 | static int | |
4e88ec4a | 630 | rcu_scale_shutdown(void *arg) |
8704baab | 631 | { |
7e866460 | 632 | wait_event(shutdown_wq, |
4e88ec4a | 633 | atomic_read(&n_rcu_scale_writer_finished) >= nrealwriters); |
8704baab | 634 | smp_mb(); /* Wake before output. */ |
4e88ec4a | 635 | rcu_scale_cleanup(); |
8704baab PM |
636 | kernel_power_off(); |
637 | return -EINVAL; | |
638 | } | |
639 | ||
e6e78b00 | 640 | /* |
4e88ec4a | 641 | * kfree_rcu() scalability tests: Start a kfree_rcu() loop on all CPUs for number |
e6e78b00 JFG |
642 | * of iterations and measure total time and number of GP for all iterations to complete. |
643 | */ | |
644 | ||
645 | torture_param(int, kfree_nthreads, -1, "Number of threads running loops of kfree_rcu()."); | |
646 | torture_param(int, kfree_alloc_num, 8000, "Number of allocations and frees done in an iteration."); | |
647 | torture_param(int, kfree_loops, 10, "Number of loops doing kfree_alloc_num allocations and frees."); | |
686fe1bf URS |
648 | torture_param(bool, kfree_rcu_test_double, false, "Do we run a kfree_rcu() double-argument scale test?"); |
649 | torture_param(bool, kfree_rcu_test_single, false, "Do we run a kfree_rcu() single-argument scale test?"); | |
e6e78b00 JFG |
650 | |
651 | static struct task_struct **kfree_reader_tasks; | |
652 | static int kfree_nrealthreads; | |
4e88ec4a PM |
653 | static atomic_t n_kfree_scale_thread_started; |
654 | static atomic_t n_kfree_scale_thread_ended; | |
e6e78b00 JFG |
655 | |
656 | struct kfree_obj { | |
657 | char kfree_obj[8]; | |
658 | struct rcu_head rh; | |
659 | }; | |
660 | ||
661 | static int | |
4e88ec4a | 662 | kfree_scale_thread(void *arg) |
e6e78b00 JFG |
663 | { |
664 | int i, loop = 0; | |
665 | long me = (long)arg; | |
666 | struct kfree_obj *alloc_ptr; | |
667 | u64 start_time, end_time; | |
12af6603 | 668 | long long mem_begin, mem_during = 0; |
686fe1bf URS |
669 | bool kfree_rcu_test_both; |
670 | DEFINE_TORTURE_RANDOM(tr); | |
e6e78b00 | 671 | |
4e88ec4a | 672 | VERBOSE_SCALEOUT_STRING("kfree_scale_thread task started"); |
e6e78b00 JFG |
673 | set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids)); |
674 | set_user_nice(current, MAX_NICE); | |
686fe1bf | 675 | kfree_rcu_test_both = (kfree_rcu_test_single == kfree_rcu_test_double); |
e6e78b00 JFG |
676 | |
677 | start_time = ktime_get_mono_fast_ns(); | |
678 | ||
4e88ec4a | 679 | if (atomic_inc_return(&n_kfree_scale_thread_started) >= kfree_nrealthreads) { |
e6e78b00 JFG |
680 | if (gp_exp) |
681 | b_rcu_gp_test_started = cur_ops->exp_completed() / 2; | |
682 | else | |
683 | b_rcu_gp_test_started = cur_ops->get_gp_seq(); | |
684 | } | |
685 | ||
686 | do { | |
12af6603 JFG |
687 | if (!mem_during) { |
688 | mem_during = mem_begin = si_mem_available(); | |
689 | } else if (loop % (kfree_loops / 4) == 0) { | |
690 | mem_during = (mem_during + si_mem_available()) / 2; | |
691 | } | |
692 | ||
e6e78b00 | 693 | for (i = 0; i < kfree_alloc_num; i++) { |
f87dc808 | 694 | alloc_ptr = kmalloc(kfree_mult * sizeof(struct kfree_obj), GFP_KERNEL); |
e6e78b00 JFG |
695 | if (!alloc_ptr) |
696 | return -ENOMEM; | |
697 | ||
686fe1bf URS |
698 | // By default kfree_rcu_test_single and kfree_rcu_test_double are |
699 | // initialized to false. If both have the same value (false or true) | |
700 | // both are randomly tested, otherwise only the one with value true | |
701 | // is tested. | |
702 | if ((kfree_rcu_test_single && !kfree_rcu_test_double) || | |
703 | (kfree_rcu_test_both && torture_random(&tr) & 0x800)) | |
704 | kfree_rcu(alloc_ptr); | |
705 | else | |
706 | kfree_rcu(alloc_ptr, rh); | |
e6e78b00 JFG |
707 | } |
708 | ||
709 | cond_resched(); | |
710 | } while (!torture_must_stop() && ++loop < kfree_loops); | |
711 | ||
4e88ec4a | 712 | if (atomic_inc_return(&n_kfree_scale_thread_ended) >= kfree_nrealthreads) { |
e6e78b00 JFG |
713 | end_time = ktime_get_mono_fast_ns(); |
714 | ||
715 | if (gp_exp) | |
716 | b_rcu_gp_test_finished = cur_ops->exp_completed() / 2; | |
717 | else | |
718 | b_rcu_gp_test_finished = cur_ops->get_gp_seq(); | |
719 | ||
12af6603 | 720 | pr_alert("Total time taken by all kfree'ers: %llu ns, loops: %d, batches: %ld, memory footprint: %lldMB\n", |
e6e78b00 | 721 | (unsigned long long)(end_time - start_time), kfree_loops, |
4e88ec4a | 722 | rcuscale_seq_diff(b_rcu_gp_test_finished, b_rcu_gp_test_started), |
12af6603 JFG |
723 | (mem_begin - mem_during) >> (20 - PAGE_SHIFT)); |
724 | ||
e6e78b00 JFG |
725 | if (shutdown) { |
726 | smp_mb(); /* Assign before wake. */ | |
727 | wake_up(&shutdown_wq); | |
728 | } | |
729 | } | |
730 | ||
4e88ec4a | 731 | torture_kthread_stopping("kfree_scale_thread"); |
e6e78b00 JFG |
732 | return 0; |
733 | } | |
734 | ||
735 | static void | |
4e88ec4a | 736 | kfree_scale_cleanup(void) |
e6e78b00 JFG |
737 | { |
738 | int i; | |
739 | ||
740 | if (torture_cleanup_begin()) | |
741 | return; | |
742 | ||
743 | if (kfree_reader_tasks) { | |
744 | for (i = 0; i < kfree_nrealthreads; i++) | |
4e88ec4a | 745 | torture_stop_kthread(kfree_scale_thread, |
e6e78b00 JFG |
746 | kfree_reader_tasks[i]); |
747 | kfree(kfree_reader_tasks); | |
748 | } | |
749 | ||
750 | torture_cleanup_end(); | |
751 | } | |
752 | ||
753 | /* | |
754 | * shutdown kthread. Just waits to be awakened, then shuts down system. | |
755 | */ | |
756 | static int | |
4e88ec4a | 757 | kfree_scale_shutdown(void *arg) |
e6e78b00 | 758 | { |
7e866460 | 759 | wait_event(shutdown_wq, |
4e88ec4a | 760 | atomic_read(&n_kfree_scale_thread_ended) >= kfree_nrealthreads); |
e6e78b00 JFG |
761 | |
762 | smp_mb(); /* Wake before output. */ | |
763 | ||
4e88ec4a | 764 | kfree_scale_cleanup(); |
e6e78b00 JFG |
765 | kernel_power_off(); |
766 | return -EINVAL; | |
767 | } | |
768 | ||
769 | static int __init | |
4e88ec4a | 770 | kfree_scale_init(void) |
e6e78b00 JFG |
771 | { |
772 | long i; | |
773 | int firsterr = 0; | |
774 | ||
775 | kfree_nrealthreads = compute_real(kfree_nthreads); | |
776 | /* Start up the kthreads. */ | |
777 | if (shutdown) { | |
778 | init_waitqueue_head(&shutdown_wq); | |
4e88ec4a | 779 | firsterr = torture_create_kthread(kfree_scale_shutdown, NULL, |
e6e78b00 | 780 | shutdown_task); |
eb77abfd | 781 | if (torture_init_error(firsterr)) |
e6e78b00 JFG |
782 | goto unwind; |
783 | schedule_timeout_uninterruptible(1); | |
784 | } | |
785 | ||
b3e2d209 | 786 | pr_alert("kfree object size=%zu\n", kfree_mult * sizeof(struct kfree_obj)); |
f87dc808 | 787 | |
e6e78b00 JFG |
788 | kfree_reader_tasks = kcalloc(kfree_nrealthreads, sizeof(kfree_reader_tasks[0]), |
789 | GFP_KERNEL); | |
790 | if (kfree_reader_tasks == NULL) { | |
791 | firsterr = -ENOMEM; | |
792 | goto unwind; | |
793 | } | |
794 | ||
795 | for (i = 0; i < kfree_nrealthreads; i++) { | |
4e88ec4a | 796 | firsterr = torture_create_kthread(kfree_scale_thread, (void *)i, |
e6e78b00 | 797 | kfree_reader_tasks[i]); |
eb77abfd | 798 | if (torture_init_error(firsterr)) |
e6e78b00 JFG |
799 | goto unwind; |
800 | } | |
801 | ||
4e88ec4a | 802 | while (atomic_read(&n_kfree_scale_thread_started) < kfree_nrealthreads) |
e6e78b00 JFG |
803 | schedule_timeout_uninterruptible(1); |
804 | ||
805 | torture_init_end(); | |
806 | return 0; | |
807 | ||
808 | unwind: | |
809 | torture_init_end(); | |
4e88ec4a | 810 | kfree_scale_cleanup(); |
e6e78b00 JFG |
811 | return firsterr; |
812 | } | |
813 | ||
8704baab | 814 | static int __init |
4e88ec4a | 815 | rcu_scale_init(void) |
8704baab PM |
816 | { |
817 | long i; | |
818 | int firsterr = 0; | |
4e88ec4a | 819 | static struct rcu_scale_ops *scale_ops[] = { |
5ce027f4 | 820 | &rcu_ops, &srcu_ops, &srcud_ops, TASKS_OPS TASKS_TRACING_OPS |
8704baab PM |
821 | }; |
822 | ||
4e88ec4a | 823 | if (!torture_init_begin(scale_type, verbose)) |
8704baab PM |
824 | return -EBUSY; |
825 | ||
4e88ec4a PM |
826 | /* Process args and announce that the scalability'er is on the job. */ |
827 | for (i = 0; i < ARRAY_SIZE(scale_ops); i++) { | |
828 | cur_ops = scale_ops[i]; | |
829 | if (strcmp(scale_type, cur_ops->name) == 0) | |
8704baab PM |
830 | break; |
831 | } | |
4e88ec4a PM |
832 | if (i == ARRAY_SIZE(scale_ops)) { |
833 | pr_alert("rcu-scale: invalid scale type: \"%s\"\n", scale_type); | |
834 | pr_alert("rcu-scale types:"); | |
835 | for (i = 0; i < ARRAY_SIZE(scale_ops); i++) | |
836 | pr_cont(" %s", scale_ops[i]->name); | |
a7538352 | 837 | pr_cont("\n"); |
8704baab | 838 | firsterr = -EINVAL; |
ad092c02 | 839 | cur_ops = NULL; |
8704baab PM |
840 | goto unwind; |
841 | } | |
842 | if (cur_ops->init) | |
843 | cur_ops->init(); | |
844 | ||
e6e78b00 | 845 | if (kfree_rcu_test) |
4e88ec4a | 846 | return kfree_scale_init(); |
e6e78b00 | 847 | |
8704baab PM |
848 | nrealwriters = compute_real(nwriters); |
849 | nrealreaders = compute_real(nreaders); | |
4e88ec4a PM |
850 | atomic_set(&n_rcu_scale_reader_started, 0); |
851 | atomic_set(&n_rcu_scale_writer_started, 0); | |
852 | atomic_set(&n_rcu_scale_writer_finished, 0); | |
853 | rcu_scale_print_module_parms(cur_ops, "Start of test"); | |
8704baab PM |
854 | |
855 | /* Start up the kthreads. */ | |
856 | ||
857 | if (shutdown) { | |
858 | init_waitqueue_head(&shutdown_wq); | |
4e88ec4a | 859 | firsterr = torture_create_kthread(rcu_scale_shutdown, NULL, |
8704baab | 860 | shutdown_task); |
eb77abfd | 861 | if (torture_init_error(firsterr)) |
8704baab PM |
862 | goto unwind; |
863 | schedule_timeout_uninterruptible(1); | |
864 | } | |
865 | reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]), | |
866 | GFP_KERNEL); | |
867 | if (reader_tasks == NULL) { | |
86e7ed1b | 868 | SCALEOUT_ERRSTRING("out of memory"); |
8704baab PM |
869 | firsterr = -ENOMEM; |
870 | goto unwind; | |
871 | } | |
872 | for (i = 0; i < nrealreaders; i++) { | |
4e88ec4a | 873 | firsterr = torture_create_kthread(rcu_scale_reader, (void *)i, |
8704baab | 874 | reader_tasks[i]); |
eb77abfd | 875 | if (torture_init_error(firsterr)) |
8704baab PM |
876 | goto unwind; |
877 | } | |
4e88ec4a | 878 | while (atomic_read(&n_rcu_scale_reader_started) < nrealreaders) |
8704baab PM |
879 | schedule_timeout_uninterruptible(1); |
880 | writer_tasks = kcalloc(nrealwriters, sizeof(reader_tasks[0]), | |
881 | GFP_KERNEL); | |
882 | writer_durations = kcalloc(nrealwriters, sizeof(*writer_durations), | |
883 | GFP_KERNEL); | |
884 | writer_n_durations = | |
885 | kcalloc(nrealwriters, sizeof(*writer_n_durations), | |
886 | GFP_KERNEL); | |
887 | if (!writer_tasks || !writer_durations || !writer_n_durations) { | |
86e7ed1b | 888 | SCALEOUT_ERRSTRING("out of memory"); |
8704baab PM |
889 | firsterr = -ENOMEM; |
890 | goto unwind; | |
891 | } | |
892 | for (i = 0; i < nrealwriters; i++) { | |
893 | writer_durations[i] = | |
894 | kcalloc(MAX_MEAS, sizeof(*writer_durations[i]), | |
895 | GFP_KERNEL); | |
05dbbfe7 WY |
896 | if (!writer_durations[i]) { |
897 | firsterr = -ENOMEM; | |
8704baab | 898 | goto unwind; |
05dbbfe7 | 899 | } |
4e88ec4a | 900 | firsterr = torture_create_kthread(rcu_scale_writer, (void *)i, |
8704baab | 901 | writer_tasks[i]); |
eb77abfd | 902 | if (torture_init_error(firsterr)) |
8704baab PM |
903 | goto unwind; |
904 | } | |
905 | torture_init_end(); | |
906 | return 0; | |
907 | ||
908 | unwind: | |
909 | torture_init_end(); | |
4e88ec4a | 910 | rcu_scale_cleanup(); |
2f2214d4 PM |
911 | if (shutdown) { |
912 | WARN_ON(!IS_MODULE(CONFIG_RCU_SCALE_TEST)); | |
913 | kernel_power_off(); | |
914 | } | |
8704baab PM |
915 | return firsterr; |
916 | } | |
917 | ||
4e88ec4a PM |
918 | module_init(rcu_scale_init); |
919 | module_exit(rcu_scale_cleanup); |