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Paul E. McKenneye9d338a2020-06-24 15:59:59 -07001// SPDX-License-Identifier: GPL-2.0+
2//
3// Torture test for smp_call_function() and friends.
4//
5// Copyright (C) Facebook, 2020.
6//
7// Author: Paul E. McKenney <paulmck@kernel.org>
8
9#define pr_fmt(fmt) fmt
10
11#include <linux/atomic.h>
12#include <linux/bitops.h>
13#include <linux/completion.h>
14#include <linux/cpu.h>
15#include <linux/delay.h>
16#include <linux/err.h>
17#include <linux/init.h>
18#include <linux/interrupt.h>
19#include <linux/kthread.h>
20#include <linux/kernel.h>
21#include <linux/mm.h>
22#include <linux/module.h>
23#include <linux/moduleparam.h>
24#include <linux/notifier.h>
25#include <linux/percpu.h>
26#include <linux/rcupdate.h>
27#include <linux/rcupdate_trace.h>
28#include <linux/reboot.h>
29#include <linux/sched.h>
30#include <linux/spinlock.h>
31#include <linux/smp.h>
32#include <linux/stat.h>
33#include <linux/srcu.h>
34#include <linux/slab.h>
35#include <linux/torture.h>
36#include <linux/types.h>
37
38#define SCFTORT_STRING "scftorture"
39#define SCFTORT_FLAG SCFTORT_STRING ": "
40
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070041#define VERBOSE_SCFTORTOUT(s, x...) \
Li Zhijian71f6ea2a2021-10-29 17:40:25 +080042 do { if (verbose) pr_alert(SCFTORT_FLAG s "\n", ## x); } while (0)
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070043
44#define VERBOSE_SCFTORTOUT_ERRSTRING(s, x...) \
Li Zhijian71f6ea2a2021-10-29 17:40:25 +080045 do { if (verbose) pr_alert(SCFTORT_FLAG "!!! " s "\n", ## x); } while (0)
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070046
47MODULE_LICENSE("GPL");
48MODULE_AUTHOR("Paul E. McKenney <paulmck@kernel.org>");
49
50// Wait until there are multiple CPUs before starting test.
51torture_param(int, holdoff, IS_BUILTIN(CONFIG_SCF_TORTURE_TEST) ? 10 : 0,
52 "Holdoff time before test start (s)");
53torture_param(int, longwait, 0, "Include ridiculously long waits? (seconds)");
54torture_param(int, nthreads, -1, "# threads, defaults to -1 for all CPUs.");
55torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
56torture_param(int, onoff_interval, 0, "Time between CPU hotplugs (s), 0=disable");
57torture_param(int, shutdown_secs, 0, "Shutdown time (ms), <= zero to disable.");
58torture_param(int, stat_interval, 60, "Number of seconds between stats printk()s.");
Paul E. McKenney85558182020-09-24 12:11:57 -070059torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable");
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070060torture_param(bool, use_cpus_read_lock, 0, "Use cpus_read_lock() to exclude CPU hotplug.");
61torture_param(int, verbose, 0, "Enable verbose debugging printk()s");
Paul E. McKenney1ac78b42020-09-03 13:09:47 -070062torture_param(int, weight_resched, -1, "Testing weight for resched_cpu() operations.");
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070063torture_param(int, weight_single, -1, "Testing weight for single-CPU no-wait operations.");
Paul E. McKenney9b9a8062021-06-24 17:53:43 -070064torture_param(int, weight_single_rpc, -1, "Testing weight for single-CPU RPC operations.");
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070065torture_param(int, weight_single_wait, -1, "Testing weight for single-CPU operations.");
Paul E. McKenney5022b8a2020-06-25 17:05:58 -070066torture_param(int, weight_many, -1, "Testing weight for multi-CPU no-wait operations.");
67torture_param(int, weight_many_wait, -1, "Testing weight for multi-CPU operations.");
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070068torture_param(int, weight_all, -1, "Testing weight for all-CPU no-wait operations.");
69torture_param(int, weight_all_wait, -1, "Testing weight for all-CPU operations.");
70
71char *torture_type = "";
72
73#ifdef MODULE
74# define SCFTORT_SHUTDOWN 0
75#else
76# define SCFTORT_SHUTDOWN 1
77#endif
78
79torture_param(bool, shutdown, SCFTORT_SHUTDOWN, "Shutdown at end of torture test.");
80
81struct scf_statistics {
82 struct task_struct *task;
83 int cpu;
Paul E. McKenney1ac78b42020-09-03 13:09:47 -070084 long long n_resched;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070085 long long n_single;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -070086 long long n_single_ofl;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -070087 long long n_single_rpc;
88 long long n_single_rpc_ofl;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070089 long long n_single_wait;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -070090 long long n_single_wait_ofl;
91 long long n_many;
92 long long n_many_wait;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -070093 long long n_all;
94 long long n_all_wait;
95};
96
97static struct scf_statistics *scf_stats_p;
98static struct task_struct *scf_torture_stats_task;
99static DEFINE_PER_CPU(long long, scf_invoked_count);
100
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700101// Data for random primitive selection
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700102#define SCF_PRIM_RESCHED 0
103#define SCF_PRIM_SINGLE 1
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700104#define SCF_PRIM_SINGLE_RPC 2
105#define SCF_PRIM_MANY 3
106#define SCF_PRIM_ALL 4
107#define SCF_NPRIMS 8 // Need wait and no-wait versions of each,
108 // except for SCF_PRIM_RESCHED and
109 // SCF_PRIM_SINGLE_RPC.
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700110
111static char *scf_prim_name[] = {
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700112 "resched_cpu",
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700113 "smp_call_function_single",
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700114 "smp_call_function_single_rpc",
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700115 "smp_call_function_many",
116 "smp_call_function",
117};
118
119struct scf_selector {
120 unsigned long scfs_weight;
121 int scfs_prim;
122 bool scfs_wait;
123};
124static struct scf_selector scf_sel_array[SCF_NPRIMS];
125static int scf_sel_array_len;
126static unsigned long scf_sel_totweight;
127
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700128// Communicate between caller and handler.
129struct scf_check {
130 bool scfc_in;
131 bool scfc_out;
132 int scfc_cpu; // -1 for not _single().
133 bool scfc_wait;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700134 bool scfc_rpc;
135 struct completion scfc_completion;
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700136};
137
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700138// Use to wait for all threads to start.
139static atomic_t n_started;
140static atomic_t n_errs;
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700141static atomic_t n_mb_in_errs;
142static atomic_t n_mb_out_errs;
143static atomic_t n_alloc_errs;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700144static bool scfdone;
Paul E. McKenneydbf83b62020-07-01 16:06:22 -0700145static char *bangstr = "";
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700146
Wei Yongjun9a52a5742020-07-02 09:56:50 -0700147static DEFINE_TORTURE_RANDOM_PERCPU(scf_torture_rand);
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700148
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700149extern void resched_cpu(int cpu); // An alternative IPI vector.
150
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700151// Print torture statistics. Caller must ensure serialization.
152static void scf_torture_stats_print(void)
153{
154 int cpu;
Paul E. McKenneydba31422020-06-30 16:13:37 -0700155 int i;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700156 long long invoked_count = 0;
157 bool isdone = READ_ONCE(scfdone);
Paul E. McKenneydba31422020-06-30 16:13:37 -0700158 struct scf_statistics scfs = {};
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700159
160 for_each_possible_cpu(cpu)
161 invoked_count += data_race(per_cpu(scf_invoked_count, cpu));
Paul E. McKenneydba31422020-06-30 16:13:37 -0700162 for (i = 0; i < nthreads; i++) {
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700163 scfs.n_resched += scf_stats_p[i].n_resched;
Paul E. McKenneydba31422020-06-30 16:13:37 -0700164 scfs.n_single += scf_stats_p[i].n_single;
165 scfs.n_single_ofl += scf_stats_p[i].n_single_ofl;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700166 scfs.n_single_rpc += scf_stats_p[i].n_single_rpc;
Paul E. McKenneydba31422020-06-30 16:13:37 -0700167 scfs.n_single_wait += scf_stats_p[i].n_single_wait;
168 scfs.n_single_wait_ofl += scf_stats_p[i].n_single_wait_ofl;
169 scfs.n_many += scf_stats_p[i].n_many;
170 scfs.n_many_wait += scf_stats_p[i].n_many_wait;
171 scfs.n_all += scf_stats_p[i].n_all;
172 scfs.n_all_wait += scf_stats_p[i].n_all_wait;
173 }
Paul E. McKenneydbf83b62020-07-01 16:06:22 -0700174 if (atomic_read(&n_errs) || atomic_read(&n_mb_in_errs) ||
175 atomic_read(&n_mb_out_errs) || atomic_read(&n_alloc_errs))
176 bangstr = "!!! ";
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700177 pr_alert("%s %sscf_invoked_count %s: %lld resched: %lld single: %lld/%lld single_ofl: %lld/%lld single_rpc: %lld single_rpc_ofl: %lld many: %lld/%lld all: %lld/%lld ",
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700178 SCFTORT_FLAG, bangstr, isdone ? "VER" : "ver", invoked_count, scfs.n_resched,
Paul E. McKenneydba31422020-06-30 16:13:37 -0700179 scfs.n_single, scfs.n_single_wait, scfs.n_single_ofl, scfs.n_single_wait_ofl,
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700180 scfs.n_single_rpc, scfs.n_single_rpc_ofl,
Paul E. McKenneydba31422020-06-30 16:13:37 -0700181 scfs.n_many, scfs.n_many_wait, scfs.n_all, scfs.n_all_wait);
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700182 torture_onoff_stats();
Paul E. McKenneydbf83b62020-07-01 16:06:22 -0700183 pr_cont("ste: %d stnmie: %d stnmoe: %d staf: %d\n", atomic_read(&n_errs),
184 atomic_read(&n_mb_in_errs), atomic_read(&n_mb_out_errs),
185 atomic_read(&n_alloc_errs));
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700186}
187
188// Periodically prints torture statistics, if periodic statistics printing
189// was specified via the stat_interval module parameter.
190static int
191scf_torture_stats(void *arg)
192{
193 VERBOSE_TOROUT_STRING("scf_torture_stats task started");
194 do {
195 schedule_timeout_interruptible(stat_interval * HZ);
196 scf_torture_stats_print();
197 torture_shutdown_absorb("scf_torture_stats");
198 } while (!torture_must_stop());
199 torture_kthread_stopping("scf_torture_stats");
200 return 0;
201}
202
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700203// Add a primitive to the scf_sel_array[].
204static void scf_sel_add(unsigned long weight, int prim, bool wait)
205{
206 struct scf_selector *scfsp = &scf_sel_array[scf_sel_array_len];
207
208 // If no weight, if array would overflow, if computing three-place
209 // percentages would overflow, or if the scf_prim_name[] array would
210 // overflow, don't bother. In the last three two cases, complain.
211 if (!weight ||
212 WARN_ON_ONCE(scf_sel_array_len >= ARRAY_SIZE(scf_sel_array)) ||
213 WARN_ON_ONCE(0 - 100000 * weight <= 100000 * scf_sel_totweight) ||
214 WARN_ON_ONCE(prim >= ARRAY_SIZE(scf_prim_name)))
215 return;
216 scf_sel_totweight += weight;
217 scfsp->scfs_weight = scf_sel_totweight;
218 scfsp->scfs_prim = prim;
219 scfsp->scfs_wait = wait;
220 scf_sel_array_len++;
221}
222
223// Dump out weighting percentages for scf_prim_name[] array.
224static void scf_sel_dump(void)
225{
226 int i;
227 unsigned long oldw = 0;
228 struct scf_selector *scfsp;
229 unsigned long w;
230
231 for (i = 0; i < scf_sel_array_len; i++) {
232 scfsp = &scf_sel_array[i];
233 w = (scfsp->scfs_weight - oldw) * 100000 / scf_sel_totweight;
234 pr_info("%s: %3lu.%03lu %s(%s)\n", __func__, w / 1000, w % 1000,
235 scf_prim_name[scfsp->scfs_prim],
236 scfsp->scfs_wait ? "wait" : "nowait");
237 oldw = scfsp->scfs_weight;
238 }
239}
240
241// Randomly pick a primitive and wait/nowait, based on weightings.
242static struct scf_selector *scf_sel_rand(struct torture_random_state *trsp)
243{
244 int i;
245 unsigned long w = torture_random(trsp) % (scf_sel_totweight + 1);
246
247 for (i = 0; i < scf_sel_array_len; i++)
248 if (scf_sel_array[i].scfs_weight >= w)
249 return &scf_sel_array[i];
250 WARN_ON_ONCE(1);
251 return &scf_sel_array[0];
252}
253
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700254// Update statistics and occasionally burn up mass quantities of CPU time,
255// if told to do so via scftorture.longwait. Otherwise, occasionally burn
256// a little bit.
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700257static void scf_handler(void *scfc_in)
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700258{
259 int i;
260 int j;
261 unsigned long r = torture_random(this_cpu_ptr(&scf_torture_rand));
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700262 struct scf_check *scfcp = scfc_in;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700263
Paul E. McKenney980205e2020-07-01 12:30:02 -0700264 if (likely(scfcp)) {
265 WRITE_ONCE(scfcp->scfc_out, false); // For multiple receivers.
266 if (WARN_ON_ONCE(unlikely(!READ_ONCE(scfcp->scfc_in))))
267 atomic_inc(&n_mb_in_errs);
268 }
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700269 this_cpu_inc(scf_invoked_count);
270 if (longwait <= 0) {
271 if (!(r & 0xffc0))
272 udelay(r & 0x3f);
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700273 goto out;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700274 }
275 if (r & 0xfff)
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700276 goto out;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700277 r = (r >> 12);
278 if (longwait <= 0) {
279 udelay((r & 0xff) + 1);
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700280 goto out;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700281 }
282 r = r % longwait + 1;
283 for (i = 0; i < r; i++) {
284 for (j = 0; j < 1000; j++) {
285 udelay(1000);
286 cpu_relax();
287 }
288 }
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700289out:
290 if (unlikely(!scfcp))
291 return;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700292 if (scfcp->scfc_wait) {
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700293 WRITE_ONCE(scfcp->scfc_out, true);
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700294 if (scfcp->scfc_rpc)
295 complete(&scfcp->scfc_completion);
296 } else {
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700297 kfree(scfcp);
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700298 }
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700299}
300
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700301// As above, but check for correct CPU.
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700302static void scf_handler_1(void *scfc_in)
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700303{
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700304 struct scf_check *scfcp = scfc_in;
305
306 if (likely(scfcp) && WARN_ONCE(smp_processor_id() != scfcp->scfc_cpu, "%s: Wanted CPU %d got CPU %d\n", __func__, scfcp->scfc_cpu, smp_processor_id())) {
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700307 atomic_inc(&n_errs);
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700308 }
309 scf_handler(scfcp);
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700310}
311
312// Randomly do an smp_call_function*() invocation.
313static void scftorture_invoke_one(struct scf_statistics *scfp, struct torture_random_state *trsp)
314{
315 uintptr_t cpu;
Paul E. McKenney676e5462020-07-01 14:13:02 -0700316 int ret = 0;
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700317 struct scf_check *scfcp = NULL;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700318 struct scf_selector *scfsp = scf_sel_rand(trsp);
319
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700320 if (use_cpus_read_lock)
321 cpus_read_lock();
322 else
323 preempt_disable();
Paul E. McKenney34e8c482020-07-01 13:49:06 -0700324 if (scfsp->scfs_prim == SCF_PRIM_SINGLE || scfsp->scfs_wait) {
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700325 scfcp = kmalloc(sizeof(*scfcp), GFP_ATOMIC);
Paul E. McKenney4df55bd2020-07-09 13:58:32 -0700326 if (WARN_ON_ONCE(!scfcp)) {
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700327 atomic_inc(&n_alloc_errs);
Paul E. McKenney4df55bd2020-07-09 13:58:32 -0700328 } else {
329 scfcp->scfc_cpu = -1;
330 scfcp->scfc_wait = scfsp->scfs_wait;
331 scfcp->scfc_out = false;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700332 scfcp->scfc_rpc = false;
Paul E. McKenney4df55bd2020-07-09 13:58:32 -0700333 }
Paul E. McKenney34e8c482020-07-01 13:49:06 -0700334 }
335 switch (scfsp->scfs_prim) {
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700336 case SCF_PRIM_RESCHED:
337 if (IS_BUILTIN(CONFIG_SCF_TORTURE_TEST)) {
338 cpu = torture_random(trsp) % nr_cpu_ids;
339 scfp->n_resched++;
340 resched_cpu(cpu);
Paul E. McKenneyc3d02582021-07-14 06:53:51 -0700341 this_cpu_inc(scf_invoked_count);
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700342 }
343 break;
Paul E. McKenney34e8c482020-07-01 13:49:06 -0700344 case SCF_PRIM_SINGLE:
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700345 cpu = torture_random(trsp) % nr_cpu_ids;
346 if (scfsp->scfs_wait)
347 scfp->n_single_wait++;
348 else
349 scfp->n_single++;
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700350 if (scfcp) {
351 scfcp->scfc_cpu = cpu;
Paul E. McKenneyee7035d2020-07-01 16:38:16 -0700352 barrier(); // Prevent race-reduction compiler optimizations.
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700353 scfcp->scfc_in = true;
354 }
355 ret = smp_call_function_single(cpu, scf_handler_1, (void *)scfcp, scfsp->scfs_wait);
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700356 if (ret) {
357 if (scfsp->scfs_wait)
358 scfp->n_single_wait_ofl++;
359 else
360 scfp->n_single_ofl++;
Paul E. McKenneyb93e21a2020-06-30 20:49:50 -0700361 kfree(scfcp);
Paul E. McKenney676e5462020-07-01 14:13:02 -0700362 scfcp = NULL;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700363 }
364 break;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700365 case SCF_PRIM_SINGLE_RPC:
366 if (!scfcp)
367 break;
368 cpu = torture_random(trsp) % nr_cpu_ids;
369 scfp->n_single_rpc++;
370 scfcp->scfc_cpu = cpu;
371 scfcp->scfc_wait = true;
372 init_completion(&scfcp->scfc_completion);
373 scfcp->scfc_rpc = true;
374 barrier(); // Prevent race-reduction compiler optimizations.
375 scfcp->scfc_in = true;
376 ret = smp_call_function_single(cpu, scf_handler_1, (void *)scfcp, 0);
377 if (!ret) {
378 if (use_cpus_read_lock)
379 cpus_read_unlock();
380 else
381 preempt_enable();
382 wait_for_completion(&scfcp->scfc_completion);
383 if (use_cpus_read_lock)
384 cpus_read_lock();
385 else
386 preempt_disable();
387 } else {
388 scfp->n_single_rpc_ofl++;
389 kfree(scfcp);
390 scfcp = NULL;
391 }
392 break;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700393 case SCF_PRIM_MANY:
394 if (scfsp->scfs_wait)
395 scfp->n_many_wait++;
396 else
397 scfp->n_many++;
Paul E. McKenneyee7035d2020-07-01 16:38:16 -0700398 if (scfcp) {
399 barrier(); // Prevent race-reduction compiler optimizations.
Paul E. McKenney980205e2020-07-01 12:30:02 -0700400 scfcp->scfc_in = true;
Paul E. McKenneyee7035d2020-07-01 16:38:16 -0700401 }
Paul E. McKenney980205e2020-07-01 12:30:02 -0700402 smp_call_function_many(cpu_online_mask, scf_handler, scfcp, scfsp->scfs_wait);
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700403 break;
404 case SCF_PRIM_ALL:
405 if (scfsp->scfs_wait)
406 scfp->n_all_wait++;
407 else
408 scfp->n_all++;
Paul E. McKenneyee7035d2020-07-01 16:38:16 -0700409 if (scfcp) {
410 barrier(); // Prevent race-reduction compiler optimizations.
Paul E. McKenney34e8c482020-07-01 13:49:06 -0700411 scfcp->scfc_in = true;
Paul E. McKenneyee7035d2020-07-01 16:38:16 -0700412 }
Paul E. McKenney34e8c482020-07-01 13:49:06 -0700413 smp_call_function(scf_handler, scfcp, scfsp->scfs_wait);
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700414 break;
Paul E. McKenneyde77d4d2020-07-02 12:15:37 -0700415 default:
416 WARN_ON_ONCE(1);
417 if (scfcp)
418 scfcp->scfc_out = true;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700419 }
Paul E. McKenney676e5462020-07-01 14:13:02 -0700420 if (scfcp && scfsp->scfs_wait) {
Paul E. McKenney9e66bf02020-07-03 15:23:19 -0700421 if (WARN_ON_ONCE((num_online_cpus() > 1 || scfsp->scfs_prim == SCF_PRIM_SINGLE) &&
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700422 !scfcp->scfc_out)) {
423 pr_warn("%s: Memory-ordering failure, scfs_prim: %d.\n", __func__, scfsp->scfs_prim);
Paul E. McKenney676e5462020-07-01 14:13:02 -0700424 atomic_inc(&n_mb_out_errs); // Leak rather than trash!
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700425 } else {
Paul E. McKenney676e5462020-07-01 14:13:02 -0700426 kfree(scfcp);
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700427 }
Paul E. McKenneyee7035d2020-07-01 16:38:16 -0700428 barrier(); // Prevent race-reduction compiler optimizations.
Paul E. McKenney676e5462020-07-01 14:13:02 -0700429 }
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700430 if (use_cpus_read_lock)
431 cpus_read_unlock();
432 else
433 preempt_enable();
434 if (!(torture_random(trsp) & 0xfff))
435 schedule_timeout_uninterruptible(1);
436}
437
438// SCF test kthread. Repeatedly does calls to members of the
439// smp_call_function() family of functions.
440static int scftorture_invoker(void *arg)
441{
Paul E. McKenneya7c072ef2020-07-02 14:15:33 -0700442 int cpu;
Paul E. McKenneyf3ea9782020-11-11 10:12:05 -0800443 int curcpu;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700444 DEFINE_TORTURE_RANDOM(rand);
445 struct scf_statistics *scfp = (struct scf_statistics *)arg;
Paul E. McKenneya7c072ef2020-07-02 14:15:33 -0700446 bool was_offline = false;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700447
448 VERBOSE_SCFTORTOUT("scftorture_invoker %d: task started", scfp->cpu);
Paul E. McKenneya7c072ef2020-07-02 14:15:33 -0700449 cpu = scfp->cpu % nr_cpu_ids;
Paul E. McKenney22b6d142021-06-04 12:37:44 -0700450 WARN_ON_ONCE(set_cpus_allowed_ptr(current, cpumask_of(cpu)));
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700451 set_user_nice(current, MAX_NICE);
452 if (holdoff)
453 schedule_timeout_interruptible(holdoff * HZ);
454
Paul E. McKenney22b6d142021-06-04 12:37:44 -0700455 VERBOSE_SCFTORTOUT("scftorture_invoker %d: Waiting for all SCF torturers from cpu %d", scfp->cpu, raw_smp_processor_id());
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700456
457 // Make sure that the CPU is affinitized appropriately during testing.
Paul E. McKenney22b6d142021-06-04 12:37:44 -0700458 curcpu = raw_smp_processor_id();
Paul E. McKenneyf3ea9782020-11-11 10:12:05 -0800459 WARN_ONCE(curcpu != scfp->cpu % nr_cpu_ids,
460 "%s: Wanted CPU %d, running on %d, nr_cpu_ids = %d\n",
461 __func__, scfp->cpu, curcpu, nr_cpu_ids);
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700462
463 if (!atomic_dec_return(&n_started))
464 while (atomic_read_acquire(&n_started)) {
465 if (torture_must_stop()) {
466 VERBOSE_SCFTORTOUT("scftorture_invoker %d ended before starting", scfp->cpu);
467 goto end;
468 }
469 schedule_timeout_uninterruptible(1);
470 }
471
472 VERBOSE_SCFTORTOUT("scftorture_invoker %d started", scfp->cpu);
473
474 do {
475 scftorture_invoke_one(scfp, &rand);
Paul E. McKenneya7c072ef2020-07-02 14:15:33 -0700476 while (cpu_is_offline(cpu) && !torture_must_stop()) {
477 schedule_timeout_interruptible(HZ / 5);
478 was_offline = true;
479 }
480 if (was_offline) {
481 set_cpus_allowed_ptr(current, cpumask_of(cpu));
482 was_offline = false;
483 }
Paul E. McKenney65bd77f2020-07-23 15:53:02 -0700484 cond_resched();
Paul E. McKenney85558182020-09-24 12:11:57 -0700485 stutter_wait("scftorture_invoker");
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700486 } while (!torture_must_stop());
487
488 VERBOSE_SCFTORTOUT("scftorture_invoker %d ended", scfp->cpu);
489end:
490 torture_kthread_stopping("scftorture_invoker");
491 return 0;
492}
493
494static void
495scftorture_print_module_parms(const char *tag)
496{
497 pr_alert(SCFTORT_FLAG
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700498 "--- %s: verbose=%d holdoff=%d longwait=%d nthreads=%d onoff_holdoff=%d onoff_interval=%d shutdown_secs=%d stat_interval=%d stutter=%d use_cpus_read_lock=%d, weight_resched=%d, weight_single=%d, weight_single_rpc=%d, weight_single_wait=%d, weight_many=%d, weight_many_wait=%d, weight_all=%d, weight_all_wait=%d\n", tag,
499 verbose, holdoff, longwait, nthreads, onoff_holdoff, onoff_interval, shutdown, stat_interval, stutter, use_cpus_read_lock, weight_resched, weight_single, weight_single_rpc, weight_single_wait, weight_many, weight_many_wait, weight_all, weight_all_wait);
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700500}
501
502static void scf_cleanup_handler(void *unused)
503{
504}
505
506static void scf_torture_cleanup(void)
507{
508 int i;
509
510 if (torture_cleanup_begin())
511 return;
512
513 WRITE_ONCE(scfdone, true);
Paul E. McKenney586e4d42021-07-09 17:53:27 -0700514 if (nthreads && scf_stats_p)
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700515 for (i = 0; i < nthreads; i++)
516 torture_stop_kthread("scftorture_invoker", scf_stats_p[i].task);
517 else
518 goto end;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700519 smp_call_function(scf_cleanup_handler, NULL, 0);
520 torture_stop_kthread(scf_torture_stats, scf_torture_stats_task);
521 scf_torture_stats_print(); // -After- the stats thread is stopped!
Paul E. McKenneydba31422020-06-30 16:13:37 -0700522 kfree(scf_stats_p); // -After- the last stats print has completed!
523 scf_stats_p = NULL;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700524
Paul E. McKenneydbf83b62020-07-01 16:06:22 -0700525 if (atomic_read(&n_errs) || atomic_read(&n_mb_in_errs) || atomic_read(&n_mb_out_errs))
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700526 scftorture_print_module_parms("End of test: FAILURE");
527 else if (torture_onoff_failures())
528 scftorture_print_module_parms("End of test: LOCK_HOTPLUG");
529 else
530 scftorture_print_module_parms("End of test: SUCCESS");
531
532end:
533 torture_cleanup_end();
534}
535
536static int __init scf_torture_init(void)
537{
538 long i;
539 int firsterr = 0;
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700540 unsigned long weight_resched1 = weight_resched;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700541 unsigned long weight_single1 = weight_single;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700542 unsigned long weight_single_rpc1 = weight_single_rpc;
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700543 unsigned long weight_single_wait1 = weight_single_wait;
544 unsigned long weight_many1 = weight_many;
545 unsigned long weight_many_wait1 = weight_many_wait;
546 unsigned long weight_all1 = weight_all;
547 unsigned long weight_all_wait1 = weight_all_wait;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700548
549 if (!torture_init_begin(SCFTORT_STRING, verbose))
550 return -EBUSY;
551
552 scftorture_print_module_parms("Start of test");
553
Paul E. McKenney2f611d02021-07-13 14:12:54 -0700554 if (weight_resched <= 0 &&
555 weight_single <= 0 && weight_single_rpc <= 0 && weight_single_wait <= 0 &&
556 weight_many <= 0 && weight_many_wait <= 0 &&
557 weight_all <= 0 && weight_all_wait <= 0) {
558 weight_resched1 = weight_resched == 0 ? 0 : 2 * nr_cpu_ids;
559 weight_single1 = weight_single == 0 ? 0 : 2 * nr_cpu_ids;
560 weight_single_rpc1 = weight_single_rpc == 0 ? 0 : 2 * nr_cpu_ids;
561 weight_single_wait1 = weight_single_wait == 0 ? 0 : 2 * nr_cpu_ids;
562 weight_many1 = weight_many == 0 ? 0 : 2;
563 weight_many_wait1 = weight_many_wait == 0 ? 0 : 2;
564 weight_all1 = weight_all == 0 ? 0 : 1;
565 weight_all_wait1 = weight_all_wait == 0 ? 0 : 1;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700566 } else {
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700567 if (weight_resched == -1)
568 weight_resched1 = 0;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700569 if (weight_single == -1)
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700570 weight_single1 = 0;
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700571 if (weight_single_rpc == -1)
572 weight_single_rpc1 = 0;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700573 if (weight_single_wait == -1)
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700574 weight_single_wait1 = 0;
575 if (weight_many == -1)
576 weight_many1 = 0;
577 if (weight_many_wait == -1)
578 weight_many_wait1 = 0;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700579 if (weight_all == -1)
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700580 weight_all1 = 0;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700581 if (weight_all_wait == -1)
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700582 weight_all_wait1 = 0;
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700583 }
Paul E. McKenneyda9366c2021-07-13 15:13:56 -0700584 if (weight_resched1 == 0 && weight_single1 == 0 && weight_single_rpc1 == 0 &&
585 weight_single_wait1 == 0 && weight_many1 == 0 && weight_many_wait1 == 0 &&
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700586 weight_all1 == 0 && weight_all_wait1 == 0) {
587 VERBOSE_SCFTORTOUT_ERRSTRING("all zero weights makes no sense");
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700588 firsterr = -EINVAL;
589 goto unwind;
590 }
Paul E. McKenney1ac78b42020-09-03 13:09:47 -0700591 if (IS_BUILTIN(CONFIG_SCF_TORTURE_TEST))
592 scf_sel_add(weight_resched1, SCF_PRIM_RESCHED, false);
593 else if (weight_resched1)
594 VERBOSE_SCFTORTOUT_ERRSTRING("built as module, weight_resched ignored");
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700595 scf_sel_add(weight_single1, SCF_PRIM_SINGLE, false);
Paul E. McKenney9b9a8062021-06-24 17:53:43 -0700596 scf_sel_add(weight_single_rpc1, SCF_PRIM_SINGLE_RPC, true);
Paul E. McKenney5022b8a2020-06-25 17:05:58 -0700597 scf_sel_add(weight_single_wait1, SCF_PRIM_SINGLE, true);
598 scf_sel_add(weight_many1, SCF_PRIM_MANY, false);
599 scf_sel_add(weight_many_wait1, SCF_PRIM_MANY, true);
600 scf_sel_add(weight_all1, SCF_PRIM_ALL, false);
601 scf_sel_add(weight_all_wait1, SCF_PRIM_ALL, true);
602 scf_sel_dump();
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700603
604 if (onoff_interval > 0) {
605 firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval, NULL);
Paul E. McKenneyf2bdf7d2021-08-05 16:01:51 -0700606 if (torture_init_error(firsterr))
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700607 goto unwind;
608 }
609 if (shutdown_secs > 0) {
610 firsterr = torture_shutdown_init(shutdown_secs, scf_torture_cleanup);
Paul E. McKenneyf2bdf7d2021-08-05 16:01:51 -0700611 if (torture_init_error(firsterr))
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700612 goto unwind;
613 }
Paul E. McKenney85558182020-09-24 12:11:57 -0700614 if (stutter > 0) {
615 firsterr = torture_stutter_init(stutter, stutter);
Paul E. McKenneyf2bdf7d2021-08-05 16:01:51 -0700616 if (torture_init_error(firsterr))
Paul E. McKenney85558182020-09-24 12:11:57 -0700617 goto unwind;
618 }
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700619
620 // Worker tasks invoking smp_call_function().
621 if (nthreads < 0)
622 nthreads = num_online_cpus();
623 scf_stats_p = kcalloc(nthreads, sizeof(scf_stats_p[0]), GFP_KERNEL);
624 if (!scf_stats_p) {
625 VERBOSE_SCFTORTOUT_ERRSTRING("out of memory");
626 firsterr = -ENOMEM;
627 goto unwind;
628 }
629
Li Zhijian71f6ea2a2021-10-29 17:40:25 +0800630 VERBOSE_SCFTORTOUT("Starting %d smp_call_function() threads", nthreads);
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700631
632 atomic_set(&n_started, nthreads);
633 for (i = 0; i < nthreads; i++) {
634 scf_stats_p[i].cpu = i;
635 firsterr = torture_create_kthread(scftorture_invoker, (void *)&scf_stats_p[i],
636 scf_stats_p[i].task);
Paul E. McKenneyf2bdf7d2021-08-05 16:01:51 -0700637 if (torture_init_error(firsterr))
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700638 goto unwind;
639 }
640 if (stat_interval > 0) {
641 firsterr = torture_create_kthread(scf_torture_stats, NULL, scf_torture_stats_task);
Paul E. McKenneyf2bdf7d2021-08-05 16:01:51 -0700642 if (torture_init_error(firsterr))
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700643 goto unwind;
644 }
645
646 torture_init_end();
647 return 0;
648
649unwind:
650 torture_init_end();
651 scf_torture_cleanup();
Paul E. McKenney2b1388f2021-07-13 14:20:35 -0700652 if (shutdown_secs) {
653 WARN_ON(!IS_MODULE(CONFIG_SCF_TORTURE_TEST));
654 kernel_power_off();
655 }
Paul E. McKenneye9d338a2020-06-24 15:59:59 -0700656 return firsterr;
657}
658
659module_init(scf_torture_init);
660module_exit(scf_torture_cleanup);