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v6.13.7
   1// SPDX-License-Identifier: LGPL-2.1
   2#define _GNU_SOURCE
   3#include <assert.h>
   4#include <linux/membarrier.h>
   5#include <pthread.h>
   6#include <sched.h>
   7#include <stdatomic.h>
   8#include <stdint.h>
   9#include <stdio.h>
  10#include <stdlib.h>
  11#include <string.h>
  12#include <syscall.h>
  13#include <unistd.h>
  14#include <poll.h>
  15#include <sys/types.h>
  16#include <signal.h>
  17#include <errno.h>
  18#include <stddef.h>
  19#include <stdbool.h>
  20
  21static inline pid_t rseq_gettid(void)
  22{
  23	return syscall(__NR_gettid);
  24}
  25
  26#define NR_INJECT	9
  27static int loop_cnt[NR_INJECT + 1];
  28
  29static int loop_cnt_1 asm("asm_loop_cnt_1") __attribute__((used));
  30static int loop_cnt_2 asm("asm_loop_cnt_2") __attribute__((used));
  31static int loop_cnt_3 asm("asm_loop_cnt_3") __attribute__((used));
  32static int loop_cnt_4 asm("asm_loop_cnt_4") __attribute__((used));
  33static int loop_cnt_5 asm("asm_loop_cnt_5") __attribute__((used));
  34static int loop_cnt_6 asm("asm_loop_cnt_6") __attribute__((used));
  35
  36static int opt_modulo, verbose;
  37
  38static int opt_yield, opt_signal, opt_sleep,
  39		opt_disable_rseq, opt_threads = 200,
  40		opt_disable_mod = 0, opt_test = 's';
  41
 
  42static long long opt_reps = 5000;
 
 
 
  43
  44static __thread __attribute__((tls_model("initial-exec")))
  45unsigned int signals_delivered;
  46
  47#ifndef BENCHMARK
  48
  49static __thread __attribute__((tls_model("initial-exec"), unused))
  50unsigned int yield_mod_cnt, nr_abort;
  51
  52#define printf_verbose(fmt, ...)			\
  53	do {						\
  54		if (verbose)				\
  55			printf(fmt, ## __VA_ARGS__);	\
  56	} while (0)
  57
  58#ifdef __i386__
  59
  60#define INJECT_ASM_REG	"eax"
  61
  62#define RSEQ_INJECT_CLOBBER \
  63	, INJECT_ASM_REG
  64
  65#define RSEQ_INJECT_ASM(n) \
  66	"mov asm_loop_cnt_" #n ", %%" INJECT_ASM_REG "\n\t" \
  67	"test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
  68	"jz 333f\n\t" \
  69	"222:\n\t" \
  70	"dec %%" INJECT_ASM_REG "\n\t" \
  71	"jnz 222b\n\t" \
  72	"333:\n\t"
  73
  74#elif defined(__x86_64__)
  75
  76#define INJECT_ASM_REG_P	"rax"
  77#define INJECT_ASM_REG		"eax"
  78
  79#define RSEQ_INJECT_CLOBBER \
  80	, INJECT_ASM_REG_P \
  81	, INJECT_ASM_REG
  82
  83#define RSEQ_INJECT_ASM(n) \
  84	"lea asm_loop_cnt_" #n "(%%rip), %%" INJECT_ASM_REG_P "\n\t" \
  85	"mov (%%" INJECT_ASM_REG_P "), %%" INJECT_ASM_REG "\n\t" \
  86	"test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
  87	"jz 333f\n\t" \
  88	"222:\n\t" \
  89	"dec %%" INJECT_ASM_REG "\n\t" \
  90	"jnz 222b\n\t" \
  91	"333:\n\t"
  92
  93#elif defined(__s390__)
  94
  95#define RSEQ_INJECT_INPUT \
  96	, [loop_cnt_1]"m"(loop_cnt[1]) \
  97	, [loop_cnt_2]"m"(loop_cnt[2]) \
  98	, [loop_cnt_3]"m"(loop_cnt[3]) \
  99	, [loop_cnt_4]"m"(loop_cnt[4]) \
 100	, [loop_cnt_5]"m"(loop_cnt[5]) \
 101	, [loop_cnt_6]"m"(loop_cnt[6])
 102
 103#define INJECT_ASM_REG	"r12"
 104
 105#define RSEQ_INJECT_CLOBBER \
 106	, INJECT_ASM_REG
 107
 108#define RSEQ_INJECT_ASM(n) \
 109	"l %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 110	"ltr %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG "\n\t" \
 111	"je 333f\n\t" \
 112	"222:\n\t" \
 113	"ahi %%" INJECT_ASM_REG ", -1\n\t" \
 114	"jnz 222b\n\t" \
 115	"333:\n\t"
 116
 117#elif defined(__ARMEL__)
 118
 119#define RSEQ_INJECT_INPUT \
 120	, [loop_cnt_1]"m"(loop_cnt[1]) \
 121	, [loop_cnt_2]"m"(loop_cnt[2]) \
 122	, [loop_cnt_3]"m"(loop_cnt[3]) \
 123	, [loop_cnt_4]"m"(loop_cnt[4]) \
 124	, [loop_cnt_5]"m"(loop_cnt[5]) \
 125	, [loop_cnt_6]"m"(loop_cnt[6])
 126
 127#define INJECT_ASM_REG	"r4"
 128
 129#define RSEQ_INJECT_CLOBBER \
 130	, INJECT_ASM_REG
 131
 132#define RSEQ_INJECT_ASM(n) \
 133	"ldr " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 134	"cmp " INJECT_ASM_REG ", #0\n\t" \
 135	"beq 333f\n\t" \
 136	"222:\n\t" \
 137	"subs " INJECT_ASM_REG ", #1\n\t" \
 138	"bne 222b\n\t" \
 139	"333:\n\t"
 140
 141#elif defined(__AARCH64EL__)
 142
 143#define RSEQ_INJECT_INPUT \
 144	, [loop_cnt_1] "Qo" (loop_cnt[1]) \
 145	, [loop_cnt_2] "Qo" (loop_cnt[2]) \
 146	, [loop_cnt_3] "Qo" (loop_cnt[3]) \
 147	, [loop_cnt_4] "Qo" (loop_cnt[4]) \
 148	, [loop_cnt_5] "Qo" (loop_cnt[5]) \
 149	, [loop_cnt_6] "Qo" (loop_cnt[6])
 150
 151#define INJECT_ASM_REG	RSEQ_ASM_TMP_REG32
 152
 153#define RSEQ_INJECT_ASM(n) \
 154	"	ldr	" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n"	\
 155	"	cbz	" INJECT_ASM_REG ", 333f\n"			\
 156	"222:\n"							\
 157	"	sub	" INJECT_ASM_REG ", " INJECT_ASM_REG ", #1\n"	\
 158	"	cbnz	" INJECT_ASM_REG ", 222b\n"			\
 159	"333:\n"
 160
 161#elif defined(__PPC__)
 162
 163#define RSEQ_INJECT_INPUT \
 164	, [loop_cnt_1]"m"(loop_cnt[1]) \
 165	, [loop_cnt_2]"m"(loop_cnt[2]) \
 166	, [loop_cnt_3]"m"(loop_cnt[3]) \
 167	, [loop_cnt_4]"m"(loop_cnt[4]) \
 168	, [loop_cnt_5]"m"(loop_cnt[5]) \
 169	, [loop_cnt_6]"m"(loop_cnt[6])
 170
 171#define INJECT_ASM_REG	"r18"
 172
 173#define RSEQ_INJECT_CLOBBER \
 174	, INJECT_ASM_REG
 175
 176#define RSEQ_INJECT_ASM(n) \
 177	"lwz %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 178	"cmpwi %%" INJECT_ASM_REG ", 0\n\t" \
 179	"beq 333f\n\t" \
 180	"222:\n\t" \
 181	"subic. %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG ", 1\n\t" \
 182	"bne 222b\n\t" \
 183	"333:\n\t"
 184
 185#elif defined(__mips__)
 186
 187#define RSEQ_INJECT_INPUT \
 188	, [loop_cnt_1]"m"(loop_cnt[1]) \
 189	, [loop_cnt_2]"m"(loop_cnt[2]) \
 190	, [loop_cnt_3]"m"(loop_cnt[3]) \
 191	, [loop_cnt_4]"m"(loop_cnt[4]) \
 192	, [loop_cnt_5]"m"(loop_cnt[5]) \
 193	, [loop_cnt_6]"m"(loop_cnt[6])
 194
 195#define INJECT_ASM_REG	"$5"
 196
 197#define RSEQ_INJECT_CLOBBER \
 198	, INJECT_ASM_REG
 199
 200#define RSEQ_INJECT_ASM(n) \
 201	"lw " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 202	"beqz " INJECT_ASM_REG ", 333f\n\t" \
 203	"222:\n\t" \
 204	"addiu " INJECT_ASM_REG ", -1\n\t" \
 205	"bnez " INJECT_ASM_REG ", 222b\n\t" \
 206	"333:\n\t"
 207#elif defined(__riscv)
 208
 209#define RSEQ_INJECT_INPUT \
 210	, [loop_cnt_1]"m"(loop_cnt[1]) \
 211	, [loop_cnt_2]"m"(loop_cnt[2]) \
 212	, [loop_cnt_3]"m"(loop_cnt[3]) \
 213	, [loop_cnt_4]"m"(loop_cnt[4]) \
 214	, [loop_cnt_5]"m"(loop_cnt[5]) \
 215	, [loop_cnt_6]"m"(loop_cnt[6])
 216
 217#define INJECT_ASM_REG	"t1"
 218
 219#define RSEQ_INJECT_CLOBBER \
 220	, INJECT_ASM_REG
 221
 222#define RSEQ_INJECT_ASM(n)					\
 223	"lw " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t"		\
 224	"beqz " INJECT_ASM_REG ", 333f\n\t"			\
 225	"222:\n\t"						\
 226	"addi  " INJECT_ASM_REG "," INJECT_ASM_REG ", -1\n\t"	\
 227	"bnez " INJECT_ASM_REG ", 222b\n\t"			\
 228	"333:\n\t"
 229
 230
 231#else
 232#error unsupported target
 233#endif
 234
 235#define RSEQ_INJECT_FAILED \
 236	nr_abort++;
 237
 238#define RSEQ_INJECT_C(n) \
 239{ \
 240	int loc_i, loc_nr_loops = loop_cnt[n]; \
 241	\
 242	for (loc_i = 0; loc_i < loc_nr_loops; loc_i++) { \
 243		rseq_barrier(); \
 244	} \
 245	if (loc_nr_loops == -1 && opt_modulo) { \
 246		if (yield_mod_cnt == opt_modulo - 1) { \
 247			if (opt_sleep > 0) \
 248				poll(NULL, 0, opt_sleep); \
 249			if (opt_yield) \
 250				sched_yield(); \
 251			if (opt_signal) \
 252				raise(SIGUSR1); \
 253			yield_mod_cnt = 0; \
 254		} else { \
 255			yield_mod_cnt++; \
 256		} \
 257	} \
 258}
 259
 260#else
 261
 262#define printf_verbose(fmt, ...)
 263
 264#endif /* BENCHMARK */
 265
 266#include "rseq.h"
 267
 268static enum rseq_mo opt_mo = RSEQ_MO_RELAXED;
 269
 270#ifdef RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV
 271#define TEST_MEMBARRIER
 272
 273static int sys_membarrier(int cmd, int flags, int cpu_id)
 274{
 275	return syscall(__NR_membarrier, cmd, flags, cpu_id);
 276}
 277#endif
 278
 279#ifdef BUILDOPT_RSEQ_PERCPU_MM_CID
 280# define RSEQ_PERCPU	RSEQ_PERCPU_MM_CID
 281static
 282int get_current_cpu_id(void)
 283{
 284	return rseq_current_mm_cid();
 285}
 286static
 287bool rseq_validate_cpu_id(void)
 288{
 289	return rseq_mm_cid_available();
 290}
 291static
 292bool rseq_use_cpu_index(void)
 293{
 294	return false;	/* Use mm_cid */
 295}
 296# ifdef TEST_MEMBARRIER
 297/*
 298 * Membarrier does not currently support targeting a mm_cid, so
 299 * issue the barrier on all cpus.
 300 */
 301static
 302int rseq_membarrier_expedited(int cpu)
 303{
 304	return sys_membarrier(MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ,
 305			      0, 0);
 306}
 307# endif /* TEST_MEMBARRIER */
 308#else
 309# define RSEQ_PERCPU	RSEQ_PERCPU_CPU_ID
 310static
 311int get_current_cpu_id(void)
 312{
 313	return rseq_cpu_start();
 314}
 315static
 316bool rseq_validate_cpu_id(void)
 317{
 318	return rseq_current_cpu_raw() >= 0;
 319}
 320static
 321bool rseq_use_cpu_index(void)
 322{
 323	return true;	/* Use cpu_id as index. */
 324}
 325# ifdef TEST_MEMBARRIER
 326static
 327int rseq_membarrier_expedited(int cpu)
 328{
 329	return sys_membarrier(MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ,
 330			      MEMBARRIER_CMD_FLAG_CPU, cpu);
 331}
 332# endif /* TEST_MEMBARRIER */
 333#endif
 334
 335struct percpu_lock_entry {
 336	intptr_t v;
 337} __attribute__((aligned(128)));
 338
 339struct percpu_lock {
 340	struct percpu_lock_entry c[CPU_SETSIZE];
 341};
 342
 343struct test_data_entry {
 344	intptr_t count;
 345} __attribute__((aligned(128)));
 346
 347struct spinlock_test_data {
 348	struct percpu_lock lock;
 349	struct test_data_entry c[CPU_SETSIZE];
 350};
 351
 352struct spinlock_thread_test_data {
 353	struct spinlock_test_data *data;
 354	long long reps;
 355	int reg;
 356};
 357
 358struct inc_test_data {
 359	struct test_data_entry c[CPU_SETSIZE];
 360};
 361
 362struct inc_thread_test_data {
 363	struct inc_test_data *data;
 364	long long reps;
 365	int reg;
 366};
 367
 368struct percpu_list_node {
 369	intptr_t data;
 370	struct percpu_list_node *next;
 371};
 372
 373struct percpu_list_entry {
 374	struct percpu_list_node *head;
 375} __attribute__((aligned(128)));
 376
 377struct percpu_list {
 378	struct percpu_list_entry c[CPU_SETSIZE];
 379};
 380
 381#define BUFFER_ITEM_PER_CPU	100
 382
 383struct percpu_buffer_node {
 384	intptr_t data;
 385};
 386
 387struct percpu_buffer_entry {
 388	intptr_t offset;
 389	intptr_t buflen;
 390	struct percpu_buffer_node **array;
 391} __attribute__((aligned(128)));
 392
 393struct percpu_buffer {
 394	struct percpu_buffer_entry c[CPU_SETSIZE];
 395};
 396
 397#define MEMCPY_BUFFER_ITEM_PER_CPU	100
 398
 399struct percpu_memcpy_buffer_node {
 400	intptr_t data1;
 401	uint64_t data2;
 402};
 403
 404struct percpu_memcpy_buffer_entry {
 405	intptr_t offset;
 406	intptr_t buflen;
 407	struct percpu_memcpy_buffer_node *array;
 408} __attribute__((aligned(128)));
 409
 410struct percpu_memcpy_buffer {
 411	struct percpu_memcpy_buffer_entry c[CPU_SETSIZE];
 412};
 413
 414/* A simple percpu spinlock. Grabs lock on current cpu. */
 415static int rseq_this_cpu_lock(struct percpu_lock *lock)
 416{
 417	int cpu;
 418
 419	for (;;) {
 420		int ret;
 421
 422		cpu = get_current_cpu_id();
 423		if (cpu < 0) {
 424			fprintf(stderr, "pid: %d: tid: %d, cpu: %d: cid: %d\n",
 425					getpid(), (int) rseq_gettid(), rseq_current_cpu_raw(), cpu);
 426			abort();
 427		}
 428		ret = rseq_cmpeqv_storev(RSEQ_MO_RELAXED, RSEQ_PERCPU,
 429					 &lock->c[cpu].v,
 430					 0, 1, cpu);
 431		if (rseq_likely(!ret))
 432			break;
 433		/* Retry if comparison fails or rseq aborts. */
 434	}
 435	/*
 436	 * Acquire semantic when taking lock after control dependency.
 437	 * Matches rseq_smp_store_release().
 438	 */
 439	rseq_smp_acquire__after_ctrl_dep();
 440	return cpu;
 441}
 442
 443static void rseq_percpu_unlock(struct percpu_lock *lock, int cpu)
 444{
 445	assert(lock->c[cpu].v == 1);
 446	/*
 447	 * Release lock, with release semantic. Matches
 448	 * rseq_smp_acquire__after_ctrl_dep().
 449	 */
 450	rseq_smp_store_release(&lock->c[cpu].v, 0);
 451}
 452
 453void *test_percpu_spinlock_thread(void *arg)
 454{
 455	struct spinlock_thread_test_data *thread_data = arg;
 456	struct spinlock_test_data *data = thread_data->data;
 457	long long i, reps;
 458
 459	if (!opt_disable_rseq && thread_data->reg &&
 460	    rseq_register_current_thread())
 461		abort();
 462	reps = thread_data->reps;
 463	for (i = 0; i < reps; i++) {
 464		int cpu = rseq_this_cpu_lock(&data->lock);
 
 
 465		data->c[cpu].count++;
 466		rseq_percpu_unlock(&data->lock, cpu);
 467#ifndef BENCHMARK
 468		if (i != 0 && !(i % (reps / 10)))
 469			printf_verbose("tid %d: count %lld\n",
 470				       (int) rseq_gettid(), i);
 471#endif
 472	}
 473	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 474		       (int) rseq_gettid(), nr_abort, signals_delivered);
 475	if (!opt_disable_rseq && thread_data->reg &&
 476	    rseq_unregister_current_thread())
 477		abort();
 478	return NULL;
 479}
 480
 481/*
 482 * A simple test which implements a sharded counter using a per-cpu
 483 * lock.  Obviously real applications might prefer to simply use a
 484 * per-cpu increment; however, this is reasonable for a test and the
 485 * lock can be extended to synchronize more complicated operations.
 486 */
 487void test_percpu_spinlock(void)
 488{
 489	const int num_threads = opt_threads;
 490	int i, ret;
 491	uint64_t sum;
 492	pthread_t test_threads[num_threads];
 493	struct spinlock_test_data data;
 494	struct spinlock_thread_test_data thread_data[num_threads];
 495
 496	memset(&data, 0, sizeof(data));
 497	for (i = 0; i < num_threads; i++) {
 498		thread_data[i].reps = opt_reps;
 499		if (opt_disable_mod <= 0 || (i % opt_disable_mod))
 500			thread_data[i].reg = 1;
 501		else
 502			thread_data[i].reg = 0;
 503		thread_data[i].data = &data;
 504		ret = pthread_create(&test_threads[i], NULL,
 505				     test_percpu_spinlock_thread,
 506				     &thread_data[i]);
 507		if (ret) {
 508			errno = ret;
 509			perror("pthread_create");
 510			abort();
 511		}
 512	}
 513
 514	for (i = 0; i < num_threads; i++) {
 515		ret = pthread_join(test_threads[i], NULL);
 516		if (ret) {
 517			errno = ret;
 518			perror("pthread_join");
 519			abort();
 520		}
 521	}
 522
 523	sum = 0;
 524	for (i = 0; i < CPU_SETSIZE; i++)
 525		sum += data.c[i].count;
 526
 527	assert(sum == (uint64_t)opt_reps * num_threads);
 528}
 529
 530void *test_percpu_inc_thread(void *arg)
 531{
 532	struct inc_thread_test_data *thread_data = arg;
 533	struct inc_test_data *data = thread_data->data;
 534	long long i, reps;
 535
 536	if (!opt_disable_rseq && thread_data->reg &&
 537	    rseq_register_current_thread())
 538		abort();
 539	reps = thread_data->reps;
 540	for (i = 0; i < reps; i++) {
 541		int ret;
 542
 543		do {
 544			int cpu;
 545
 546			cpu = get_current_cpu_id();
 547			ret = rseq_addv(RSEQ_MO_RELAXED, RSEQ_PERCPU,
 548					&data->c[cpu].count, 1, cpu);
 549		} while (rseq_unlikely(ret));
 550#ifndef BENCHMARK
 551		if (i != 0 && !(i % (reps / 10)))
 552			printf_verbose("tid %d: count %lld\n",
 553				       (int) rseq_gettid(), i);
 554#endif
 555	}
 556	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 557		       (int) rseq_gettid(), nr_abort, signals_delivered);
 558	if (!opt_disable_rseq && thread_data->reg &&
 559	    rseq_unregister_current_thread())
 560		abort();
 561	return NULL;
 562}
 563
 564void test_percpu_inc(void)
 565{
 566	const int num_threads = opt_threads;
 567	int i, ret;
 568	uint64_t sum;
 569	pthread_t test_threads[num_threads];
 570	struct inc_test_data data;
 571	struct inc_thread_test_data thread_data[num_threads];
 572
 573	memset(&data, 0, sizeof(data));
 574	for (i = 0; i < num_threads; i++) {
 575		thread_data[i].reps = opt_reps;
 576		if (opt_disable_mod <= 0 || (i % opt_disable_mod))
 577			thread_data[i].reg = 1;
 578		else
 579			thread_data[i].reg = 0;
 580		thread_data[i].data = &data;
 581		ret = pthread_create(&test_threads[i], NULL,
 582				     test_percpu_inc_thread,
 583				     &thread_data[i]);
 584		if (ret) {
 585			errno = ret;
 586			perror("pthread_create");
 587			abort();
 588		}
 589	}
 590
 591	for (i = 0; i < num_threads; i++) {
 592		ret = pthread_join(test_threads[i], NULL);
 593		if (ret) {
 594			errno = ret;
 595			perror("pthread_join");
 596			abort();
 597		}
 598	}
 599
 600	sum = 0;
 601	for (i = 0; i < CPU_SETSIZE; i++)
 602		sum += data.c[i].count;
 603
 604	assert(sum == (uint64_t)opt_reps * num_threads);
 605}
 606
 607void this_cpu_list_push(struct percpu_list *list,
 608			struct percpu_list_node *node,
 609			int *_cpu)
 610{
 611	int cpu;
 612
 613	for (;;) {
 614		intptr_t *targetptr, newval, expect;
 615		int ret;
 616
 617		cpu = get_current_cpu_id();
 618		/* Load list->c[cpu].head with single-copy atomicity. */
 619		expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head);
 620		newval = (intptr_t)node;
 621		targetptr = (intptr_t *)&list->c[cpu].head;
 622		node->next = (struct percpu_list_node *)expect;
 623		ret = rseq_cmpeqv_storev(RSEQ_MO_RELAXED, RSEQ_PERCPU,
 624					 targetptr, expect, newval, cpu);
 625		if (rseq_likely(!ret))
 626			break;
 627		/* Retry if comparison fails or rseq aborts. */
 628	}
 629	if (_cpu)
 630		*_cpu = cpu;
 631}
 632
 633/*
 634 * Unlike a traditional lock-less linked list; the availability of a
 635 * rseq primitive allows us to implement pop without concerns over
 636 * ABA-type races.
 637 */
 638struct percpu_list_node *this_cpu_list_pop(struct percpu_list *list,
 639					   int *_cpu)
 640{
 641	struct percpu_list_node *node = NULL;
 642	int cpu;
 643
 644	for (;;) {
 645		struct percpu_list_node *head;
 646		intptr_t *targetptr, expectnot, *load;
 647		long offset;
 648		int ret;
 649
 650		cpu = get_current_cpu_id();
 651		targetptr = (intptr_t *)&list->c[cpu].head;
 652		expectnot = (intptr_t)NULL;
 653		offset = offsetof(struct percpu_list_node, next);
 654		load = (intptr_t *)&head;
 655		ret = rseq_cmpnev_storeoffp_load(RSEQ_MO_RELAXED, RSEQ_PERCPU,
 656						 targetptr, expectnot,
 657						 offset, load, cpu);
 658		if (rseq_likely(!ret)) {
 659			node = head;
 660			break;
 661		}
 662		if (ret > 0)
 663			break;
 664		/* Retry if rseq aborts. */
 665	}
 666	if (_cpu)
 667		*_cpu = cpu;
 668	return node;
 669}
 670
 671/*
 672 * __percpu_list_pop is not safe against concurrent accesses. Should
 673 * only be used on lists that are not concurrently modified.
 674 */
 675struct percpu_list_node *__percpu_list_pop(struct percpu_list *list, int cpu)
 676{
 677	struct percpu_list_node *node;
 678
 679	node = list->c[cpu].head;
 680	if (!node)
 681		return NULL;
 682	list->c[cpu].head = node->next;
 683	return node;
 684}
 685
 686void *test_percpu_list_thread(void *arg)
 687{
 688	long long i, reps;
 689	struct percpu_list *list = (struct percpu_list *)arg;
 690
 691	if (!opt_disable_rseq && rseq_register_current_thread())
 692		abort();
 693
 694	reps = opt_reps;
 695	for (i = 0; i < reps; i++) {
 696		struct percpu_list_node *node;
 697
 698		node = this_cpu_list_pop(list, NULL);
 699		if (opt_yield)
 700			sched_yield();  /* encourage shuffling */
 701		if (node)
 702			this_cpu_list_push(list, node, NULL);
 703	}
 704
 705	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 706		       (int) rseq_gettid(), nr_abort, signals_delivered);
 707	if (!opt_disable_rseq && rseq_unregister_current_thread())
 708		abort();
 709
 710	return NULL;
 711}
 712
 713/* Simultaneous modification to a per-cpu linked list from many threads.  */
 714void test_percpu_list(void)
 715{
 716	const int num_threads = opt_threads;
 717	int i, j, ret;
 718	uint64_t sum = 0, expected_sum = 0;
 719	struct percpu_list list;
 720	pthread_t test_threads[num_threads];
 721	cpu_set_t allowed_cpus;
 722
 723	memset(&list, 0, sizeof(list));
 724
 725	/* Generate list entries for every usable cpu. */
 726	sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
 727	for (i = 0; i < CPU_SETSIZE; i++) {
 728		if (rseq_use_cpu_index() && !CPU_ISSET(i, &allowed_cpus))
 729			continue;
 730		for (j = 1; j <= 100; j++) {
 731			struct percpu_list_node *node;
 732
 733			expected_sum += j;
 734
 735			node = malloc(sizeof(*node));
 736			assert(node);
 737			node->data = j;
 738			node->next = list.c[i].head;
 739			list.c[i].head = node;
 740		}
 741	}
 742
 743	for (i = 0; i < num_threads; i++) {
 744		ret = pthread_create(&test_threads[i], NULL,
 745				     test_percpu_list_thread, &list);
 746		if (ret) {
 747			errno = ret;
 748			perror("pthread_create");
 749			abort();
 750		}
 751	}
 752
 753	for (i = 0; i < num_threads; i++) {
 754		ret = pthread_join(test_threads[i], NULL);
 755		if (ret) {
 756			errno = ret;
 757			perror("pthread_join");
 758			abort();
 759		}
 760	}
 761
 762	for (i = 0; i < CPU_SETSIZE; i++) {
 763		struct percpu_list_node *node;
 764
 765		if (rseq_use_cpu_index() && !CPU_ISSET(i, &allowed_cpus))
 766			continue;
 767
 768		while ((node = __percpu_list_pop(&list, i))) {
 769			sum += node->data;
 770			free(node);
 771		}
 772	}
 773
 774	/*
 775	 * All entries should now be accounted for (unless some external
 776	 * actor is interfering with our allowed affinity while this
 777	 * test is running).
 778	 */
 779	assert(sum == expected_sum);
 780}
 781
 782bool this_cpu_buffer_push(struct percpu_buffer *buffer,
 783			  struct percpu_buffer_node *node,
 784			  int *_cpu)
 785{
 786	bool result = false;
 787	int cpu;
 788
 789	for (;;) {
 790		intptr_t *targetptr_spec, newval_spec;
 791		intptr_t *targetptr_final, newval_final;
 792		intptr_t offset;
 793		int ret;
 794
 795		cpu = get_current_cpu_id();
 796		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 797		if (offset == buffer->c[cpu].buflen)
 798			break;
 799		newval_spec = (intptr_t)node;
 800		targetptr_spec = (intptr_t *)&buffer->c[cpu].array[offset];
 801		newval_final = offset + 1;
 802		targetptr_final = &buffer->c[cpu].offset;
 803		ret = rseq_cmpeqv_trystorev_storev(opt_mo, RSEQ_PERCPU,
 804			targetptr_final, offset, targetptr_spec,
 805			newval_spec, newval_final, cpu);
 
 
 
 
 
 806		if (rseq_likely(!ret)) {
 807			result = true;
 808			break;
 809		}
 810		/* Retry if comparison fails or rseq aborts. */
 811	}
 812	if (_cpu)
 813		*_cpu = cpu;
 814	return result;
 815}
 816
 817struct percpu_buffer_node *this_cpu_buffer_pop(struct percpu_buffer *buffer,
 818					       int *_cpu)
 819{
 820	struct percpu_buffer_node *head;
 821	int cpu;
 822
 823	for (;;) {
 824		intptr_t *targetptr, newval;
 825		intptr_t offset;
 826		int ret;
 827
 828		cpu = get_current_cpu_id();
 829		/* Load offset with single-copy atomicity. */
 830		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 831		if (offset == 0) {
 832			head = NULL;
 833			break;
 834		}
 835		head = RSEQ_READ_ONCE(buffer->c[cpu].array[offset - 1]);
 836		newval = offset - 1;
 837		targetptr = (intptr_t *)&buffer->c[cpu].offset;
 838		ret = rseq_cmpeqv_cmpeqv_storev(RSEQ_MO_RELAXED, RSEQ_PERCPU,
 839			targetptr, offset,
 840			(intptr_t *)&buffer->c[cpu].array[offset - 1],
 841			(intptr_t)head, newval, cpu);
 842		if (rseq_likely(!ret))
 843			break;
 844		/* Retry if comparison fails or rseq aborts. */
 845	}
 846	if (_cpu)
 847		*_cpu = cpu;
 848	return head;
 849}
 850
 851/*
 852 * __percpu_buffer_pop is not safe against concurrent accesses. Should
 853 * only be used on buffers that are not concurrently modified.
 854 */
 855struct percpu_buffer_node *__percpu_buffer_pop(struct percpu_buffer *buffer,
 856					       int cpu)
 857{
 858	struct percpu_buffer_node *head;
 859	intptr_t offset;
 860
 861	offset = buffer->c[cpu].offset;
 862	if (offset == 0)
 863		return NULL;
 864	head = buffer->c[cpu].array[offset - 1];
 865	buffer->c[cpu].offset = offset - 1;
 866	return head;
 867}
 868
 869void *test_percpu_buffer_thread(void *arg)
 870{
 871	long long i, reps;
 872	struct percpu_buffer *buffer = (struct percpu_buffer *)arg;
 873
 874	if (!opt_disable_rseq && rseq_register_current_thread())
 875		abort();
 876
 877	reps = opt_reps;
 878	for (i = 0; i < reps; i++) {
 879		struct percpu_buffer_node *node;
 880
 881		node = this_cpu_buffer_pop(buffer, NULL);
 882		if (opt_yield)
 883			sched_yield();  /* encourage shuffling */
 884		if (node) {
 885			if (!this_cpu_buffer_push(buffer, node, NULL)) {
 886				/* Should increase buffer size. */
 887				abort();
 888			}
 889		}
 890	}
 891
 892	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 893		       (int) rseq_gettid(), nr_abort, signals_delivered);
 894	if (!opt_disable_rseq && rseq_unregister_current_thread())
 895		abort();
 896
 897	return NULL;
 898}
 899
 900/* Simultaneous modification to a per-cpu buffer from many threads.  */
 901void test_percpu_buffer(void)
 902{
 903	const int num_threads = opt_threads;
 904	int i, j, ret;
 905	uint64_t sum = 0, expected_sum = 0;
 906	struct percpu_buffer buffer;
 907	pthread_t test_threads[num_threads];
 908	cpu_set_t allowed_cpus;
 909
 910	memset(&buffer, 0, sizeof(buffer));
 911
 912	/* Generate list entries for every usable cpu. */
 913	sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
 914	for (i = 0; i < CPU_SETSIZE; i++) {
 915		if (rseq_use_cpu_index() && !CPU_ISSET(i, &allowed_cpus))
 916			continue;
 917		/* Worse-case is every item in same CPU. */
 918		buffer.c[i].array =
 919			malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE *
 920			       BUFFER_ITEM_PER_CPU);
 921		assert(buffer.c[i].array);
 922		buffer.c[i].buflen = CPU_SETSIZE * BUFFER_ITEM_PER_CPU;
 923		for (j = 1; j <= BUFFER_ITEM_PER_CPU; j++) {
 924			struct percpu_buffer_node *node;
 925
 926			expected_sum += j;
 927
 928			/*
 929			 * We could theoretically put the word-sized
 930			 * "data" directly in the buffer. However, we
 931			 * want to model objects that would not fit
 932			 * within a single word, so allocate an object
 933			 * for each node.
 934			 */
 935			node = malloc(sizeof(*node));
 936			assert(node);
 937			node->data = j;
 938			buffer.c[i].array[j - 1] = node;
 939			buffer.c[i].offset++;
 940		}
 941	}
 942
 943	for (i = 0; i < num_threads; i++) {
 944		ret = pthread_create(&test_threads[i], NULL,
 945				     test_percpu_buffer_thread, &buffer);
 946		if (ret) {
 947			errno = ret;
 948			perror("pthread_create");
 949			abort();
 950		}
 951	}
 952
 953	for (i = 0; i < num_threads; i++) {
 954		ret = pthread_join(test_threads[i], NULL);
 955		if (ret) {
 956			errno = ret;
 957			perror("pthread_join");
 958			abort();
 959		}
 960	}
 961
 962	for (i = 0; i < CPU_SETSIZE; i++) {
 963		struct percpu_buffer_node *node;
 964
 965		if (rseq_use_cpu_index() && !CPU_ISSET(i, &allowed_cpus))
 966			continue;
 967
 968		while ((node = __percpu_buffer_pop(&buffer, i))) {
 969			sum += node->data;
 970			free(node);
 971		}
 972		free(buffer.c[i].array);
 973	}
 974
 975	/*
 976	 * All entries should now be accounted for (unless some external
 977	 * actor is interfering with our allowed affinity while this
 978	 * test is running).
 979	 */
 980	assert(sum == expected_sum);
 981}
 982
 983bool this_cpu_memcpy_buffer_push(struct percpu_memcpy_buffer *buffer,
 984				 struct percpu_memcpy_buffer_node item,
 985				 int *_cpu)
 986{
 987	bool result = false;
 988	int cpu;
 989
 990	for (;;) {
 991		intptr_t *targetptr_final, newval_final, offset;
 992		char *destptr, *srcptr;
 993		size_t copylen;
 994		int ret;
 995
 996		cpu = get_current_cpu_id();
 997		/* Load offset with single-copy atomicity. */
 998		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 999		if (offset == buffer->c[cpu].buflen)
1000			break;
1001		destptr = (char *)&buffer->c[cpu].array[offset];
1002		srcptr = (char *)&item;
1003		/* copylen must be <= 4kB. */
1004		copylen = sizeof(item);
1005		newval_final = offset + 1;
1006		targetptr_final = &buffer->c[cpu].offset;
1007		ret = rseq_cmpeqv_trymemcpy_storev(
1008			opt_mo, RSEQ_PERCPU,
1009			targetptr_final, offset,
1010			destptr, srcptr, copylen,
1011			newval_final, cpu);
 
 
 
 
1012		if (rseq_likely(!ret)) {
1013			result = true;
1014			break;
1015		}
1016		/* Retry if comparison fails or rseq aborts. */
1017	}
1018	if (_cpu)
1019		*_cpu = cpu;
1020	return result;
1021}
1022
1023bool this_cpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer,
1024				struct percpu_memcpy_buffer_node *item,
1025				int *_cpu)
1026{
1027	bool result = false;
1028	int cpu;
1029
1030	for (;;) {
1031		intptr_t *targetptr_final, newval_final, offset;
1032		char *destptr, *srcptr;
1033		size_t copylen;
1034		int ret;
1035
1036		cpu = get_current_cpu_id();
1037		/* Load offset with single-copy atomicity. */
1038		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
1039		if (offset == 0)
1040			break;
1041		destptr = (char *)item;
1042		srcptr = (char *)&buffer->c[cpu].array[offset - 1];
1043		/* copylen must be <= 4kB. */
1044		copylen = sizeof(*item);
1045		newval_final = offset - 1;
1046		targetptr_final = &buffer->c[cpu].offset;
1047		ret = rseq_cmpeqv_trymemcpy_storev(RSEQ_MO_RELAXED, RSEQ_PERCPU,
1048			targetptr_final, offset, destptr, srcptr, copylen,
1049			newval_final, cpu);
1050		if (rseq_likely(!ret)) {
1051			result = true;
1052			break;
1053		}
1054		/* Retry if comparison fails or rseq aborts. */
1055	}
1056	if (_cpu)
1057		*_cpu = cpu;
1058	return result;
1059}
1060
1061/*
1062 * __percpu_memcpy_buffer_pop is not safe against concurrent accesses. Should
1063 * only be used on buffers that are not concurrently modified.
1064 */
1065bool __percpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer,
1066				struct percpu_memcpy_buffer_node *item,
1067				int cpu)
1068{
1069	intptr_t offset;
1070
1071	offset = buffer->c[cpu].offset;
1072	if (offset == 0)
1073		return false;
1074	memcpy(item, &buffer->c[cpu].array[offset - 1], sizeof(*item));
1075	buffer->c[cpu].offset = offset - 1;
1076	return true;
1077}
1078
1079void *test_percpu_memcpy_buffer_thread(void *arg)
1080{
1081	long long i, reps;
1082	struct percpu_memcpy_buffer *buffer = (struct percpu_memcpy_buffer *)arg;
1083
1084	if (!opt_disable_rseq && rseq_register_current_thread())
1085		abort();
1086
1087	reps = opt_reps;
1088	for (i = 0; i < reps; i++) {
1089		struct percpu_memcpy_buffer_node item;
1090		bool result;
1091
1092		result = this_cpu_memcpy_buffer_pop(buffer, &item, NULL);
1093		if (opt_yield)
1094			sched_yield();  /* encourage shuffling */
1095		if (result) {
1096			if (!this_cpu_memcpy_buffer_push(buffer, item, NULL)) {
1097				/* Should increase buffer size. */
1098				abort();
1099			}
1100		}
1101	}
1102
1103	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
1104		       (int) rseq_gettid(), nr_abort, signals_delivered);
1105	if (!opt_disable_rseq && rseq_unregister_current_thread())
1106		abort();
1107
1108	return NULL;
1109}
1110
1111/* Simultaneous modification to a per-cpu buffer from many threads.  */
1112void test_percpu_memcpy_buffer(void)
1113{
1114	const int num_threads = opt_threads;
1115	int i, j, ret;
1116	uint64_t sum = 0, expected_sum = 0;
1117	struct percpu_memcpy_buffer buffer;
1118	pthread_t test_threads[num_threads];
1119	cpu_set_t allowed_cpus;
1120
1121	memset(&buffer, 0, sizeof(buffer));
1122
1123	/* Generate list entries for every usable cpu. */
1124	sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
1125	for (i = 0; i < CPU_SETSIZE; i++) {
1126		if (rseq_use_cpu_index() && !CPU_ISSET(i, &allowed_cpus))
1127			continue;
1128		/* Worse-case is every item in same CPU. */
1129		buffer.c[i].array =
1130			malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE *
1131			       MEMCPY_BUFFER_ITEM_PER_CPU);
1132		assert(buffer.c[i].array);
1133		buffer.c[i].buflen = CPU_SETSIZE * MEMCPY_BUFFER_ITEM_PER_CPU;
1134		for (j = 1; j <= MEMCPY_BUFFER_ITEM_PER_CPU; j++) {
1135			expected_sum += 2 * j + 1;
1136
1137			/*
1138			 * We could theoretically put the word-sized
1139			 * "data" directly in the buffer. However, we
1140			 * want to model objects that would not fit
1141			 * within a single word, so allocate an object
1142			 * for each node.
1143			 */
1144			buffer.c[i].array[j - 1].data1 = j;
1145			buffer.c[i].array[j - 1].data2 = j + 1;
1146			buffer.c[i].offset++;
1147		}
1148	}
1149
1150	for (i = 0; i < num_threads; i++) {
1151		ret = pthread_create(&test_threads[i], NULL,
1152				     test_percpu_memcpy_buffer_thread,
1153				     &buffer);
1154		if (ret) {
1155			errno = ret;
1156			perror("pthread_create");
1157			abort();
1158		}
1159	}
1160
1161	for (i = 0; i < num_threads; i++) {
1162		ret = pthread_join(test_threads[i], NULL);
1163		if (ret) {
1164			errno = ret;
1165			perror("pthread_join");
1166			abort();
1167		}
1168	}
1169
1170	for (i = 0; i < CPU_SETSIZE; i++) {
1171		struct percpu_memcpy_buffer_node item;
1172
1173		if (rseq_use_cpu_index() && !CPU_ISSET(i, &allowed_cpus))
1174			continue;
1175
1176		while (__percpu_memcpy_buffer_pop(&buffer, &item, i)) {
1177			sum += item.data1;
1178			sum += item.data2;
1179		}
1180		free(buffer.c[i].array);
1181	}
1182
1183	/*
1184	 * All entries should now be accounted for (unless some external
1185	 * actor is interfering with our allowed affinity while this
1186	 * test is running).
1187	 */
1188	assert(sum == expected_sum);
1189}
1190
1191static void test_signal_interrupt_handler(int signo)
1192{
1193	signals_delivered++;
1194}
1195
1196static int set_signal_handler(void)
1197{
1198	int ret = 0;
1199	struct sigaction sa;
1200	sigset_t sigset;
1201
1202	ret = sigemptyset(&sigset);
1203	if (ret < 0) {
1204		perror("sigemptyset");
1205		return ret;
1206	}
1207
1208	sa.sa_handler = test_signal_interrupt_handler;
1209	sa.sa_mask = sigset;
1210	sa.sa_flags = 0;
1211	ret = sigaction(SIGUSR1, &sa, NULL);
1212	if (ret < 0) {
1213		perror("sigaction");
1214		return ret;
1215	}
1216
1217	printf_verbose("Signal handler set for SIGUSR1\n");
1218
1219	return ret;
1220}
1221
1222/* Test MEMBARRIER_CMD_PRIVATE_RESTART_RSEQ_ON_CPU membarrier command. */
1223#ifdef TEST_MEMBARRIER
1224struct test_membarrier_thread_args {
1225	int stop;
1226	intptr_t percpu_list_ptr;
1227};
1228
1229/* Worker threads modify data in their "active" percpu lists. */
1230void *test_membarrier_worker_thread(void *arg)
1231{
1232	struct test_membarrier_thread_args *args =
1233		(struct test_membarrier_thread_args *)arg;
1234	const int iters = opt_reps;
1235	int i;
1236
1237	if (rseq_register_current_thread()) {
1238		fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
1239			errno, strerror(errno));
1240		abort();
1241	}
1242
1243	/* Wait for initialization. */
1244	while (!__atomic_load_n(&args->percpu_list_ptr, __ATOMIC_ACQUIRE)) {}
1245
1246	for (i = 0; i < iters; ++i) {
1247		int ret;
1248
1249		do {
1250			int cpu = get_current_cpu_id();
1251
1252			ret = rseq_offset_deref_addv(RSEQ_MO_RELAXED, RSEQ_PERCPU,
1253				&args->percpu_list_ptr,
1254				sizeof(struct percpu_list_entry) * cpu, 1, cpu);
1255		} while (rseq_unlikely(ret));
1256	}
1257
1258	if (rseq_unregister_current_thread()) {
1259		fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n",
1260			errno, strerror(errno));
1261		abort();
1262	}
1263	return NULL;
1264}
1265
1266void test_membarrier_init_percpu_list(struct percpu_list *list)
1267{
1268	int i;
1269
1270	memset(list, 0, sizeof(*list));
1271	for (i = 0; i < CPU_SETSIZE; i++) {
1272		struct percpu_list_node *node;
1273
1274		node = malloc(sizeof(*node));
1275		assert(node);
1276		node->data = 0;
1277		node->next = NULL;
1278		list->c[i].head = node;
1279	}
1280}
1281
1282void test_membarrier_free_percpu_list(struct percpu_list *list)
1283{
1284	int i;
1285
1286	for (i = 0; i < CPU_SETSIZE; i++)
1287		free(list->c[i].head);
1288}
1289
1290/*
1291 * The manager thread swaps per-cpu lists that worker threads see,
1292 * and validates that there are no unexpected modifications.
1293 */
1294void *test_membarrier_manager_thread(void *arg)
1295{
1296	struct test_membarrier_thread_args *args =
1297		(struct test_membarrier_thread_args *)arg;
1298	struct percpu_list list_a, list_b;
1299	intptr_t expect_a = 0, expect_b = 0;
1300	int cpu_a = 0, cpu_b = 0;
1301
1302	if (rseq_register_current_thread()) {
1303		fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
1304			errno, strerror(errno));
1305		abort();
1306	}
1307
1308	/* Init lists. */
1309	test_membarrier_init_percpu_list(&list_a);
1310	test_membarrier_init_percpu_list(&list_b);
1311
1312	__atomic_store_n(&args->percpu_list_ptr, (intptr_t)&list_a, __ATOMIC_RELEASE);
1313
1314	while (!__atomic_load_n(&args->stop, __ATOMIC_ACQUIRE)) {
1315		/* list_a is "active". */
1316		cpu_a = rand() % CPU_SETSIZE;
1317		/*
1318		 * As list_b is "inactive", we should never see changes
1319		 * to list_b.
1320		 */
1321		if (expect_b != __atomic_load_n(&list_b.c[cpu_b].head->data, __ATOMIC_ACQUIRE)) {
1322			fprintf(stderr, "Membarrier test failed\n");
1323			abort();
1324		}
1325
1326		/* Make list_b "active". */
1327		__atomic_store_n(&args->percpu_list_ptr, (intptr_t)&list_b, __ATOMIC_RELEASE);
1328		if (rseq_membarrier_expedited(cpu_a) &&
1329				errno != ENXIO /* missing CPU */) {
1330			perror("sys_membarrier");
1331			abort();
1332		}
1333		/*
1334		 * Cpu A should now only modify list_b, so the values
1335		 * in list_a should be stable.
1336		 */
1337		expect_a = __atomic_load_n(&list_a.c[cpu_a].head->data, __ATOMIC_ACQUIRE);
1338
1339		cpu_b = rand() % CPU_SETSIZE;
1340		/*
1341		 * As list_a is "inactive", we should never see changes
1342		 * to list_a.
1343		 */
1344		if (expect_a != __atomic_load_n(&list_a.c[cpu_a].head->data, __ATOMIC_ACQUIRE)) {
1345			fprintf(stderr, "Membarrier test failed\n");
1346			abort();
1347		}
1348
1349		/* Make list_a "active". */
1350		__atomic_store_n(&args->percpu_list_ptr, (intptr_t)&list_a, __ATOMIC_RELEASE);
1351		if (rseq_membarrier_expedited(cpu_b) &&
1352				errno != ENXIO /* missing CPU*/) {
1353			perror("sys_membarrier");
1354			abort();
1355		}
1356		/* Remember a value from list_b. */
1357		expect_b = __atomic_load_n(&list_b.c[cpu_b].head->data, __ATOMIC_ACQUIRE);
1358	}
1359
1360	test_membarrier_free_percpu_list(&list_a);
1361	test_membarrier_free_percpu_list(&list_b);
1362
1363	if (rseq_unregister_current_thread()) {
1364		fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n",
1365			errno, strerror(errno));
1366		abort();
1367	}
1368	return NULL;
1369}
1370
1371void test_membarrier(void)
1372{
1373	const int num_threads = opt_threads;
1374	struct test_membarrier_thread_args thread_args;
1375	pthread_t worker_threads[num_threads];
1376	pthread_t manager_thread;
1377	int i, ret;
1378
1379	if (sys_membarrier(MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED_RSEQ, 0, 0)) {
1380		perror("sys_membarrier");
1381		abort();
1382	}
1383
1384	thread_args.stop = 0;
1385	thread_args.percpu_list_ptr = 0;
1386	ret = pthread_create(&manager_thread, NULL,
1387			test_membarrier_manager_thread, &thread_args);
1388	if (ret) {
1389		errno = ret;
1390		perror("pthread_create");
1391		abort();
1392	}
1393
1394	for (i = 0; i < num_threads; i++) {
1395		ret = pthread_create(&worker_threads[i], NULL,
1396				test_membarrier_worker_thread, &thread_args);
1397		if (ret) {
1398			errno = ret;
1399			perror("pthread_create");
1400			abort();
1401		}
1402	}
1403
1404
1405	for (i = 0; i < num_threads; i++) {
1406		ret = pthread_join(worker_threads[i], NULL);
1407		if (ret) {
1408			errno = ret;
1409			perror("pthread_join");
1410			abort();
1411		}
1412	}
1413
1414	__atomic_store_n(&thread_args.stop, 1, __ATOMIC_RELEASE);
1415	ret = pthread_join(manager_thread, NULL);
1416	if (ret) {
1417		errno = ret;
1418		perror("pthread_join");
1419		abort();
1420	}
1421}
1422#else /* TEST_MEMBARRIER */
1423void test_membarrier(void)
1424{
1425	fprintf(stderr, "rseq_offset_deref_addv is not implemented on this architecture. "
1426			"Skipping membarrier test.\n");
1427}
1428#endif
1429
1430static void show_usage(int argc, char **argv)
1431{
1432	printf("Usage : %s <OPTIONS>\n",
1433		argv[0]);
1434	printf("OPTIONS:\n");
1435	printf("	[-1 loops] Number of loops for delay injection 1\n");
1436	printf("	[-2 loops] Number of loops for delay injection 2\n");
1437	printf("	[-3 loops] Number of loops for delay injection 3\n");
1438	printf("	[-4 loops] Number of loops for delay injection 4\n");
1439	printf("	[-5 loops] Number of loops for delay injection 5\n");
1440	printf("	[-6 loops] Number of loops for delay injection 6\n");
1441	printf("	[-7 loops] Number of loops for delay injection 7 (-1 to enable -m)\n");
1442	printf("	[-8 loops] Number of loops for delay injection 8 (-1 to enable -m)\n");
1443	printf("	[-9 loops] Number of loops for delay injection 9 (-1 to enable -m)\n");
1444	printf("	[-m N] Yield/sleep/kill every modulo N (default 0: disabled) (>= 0)\n");
1445	printf("	[-y] Yield\n");
1446	printf("	[-k] Kill thread with signal\n");
1447	printf("	[-s S] S: =0: disabled (default), >0: sleep time (ms)\n");
1448	printf("	[-t N] Number of threads (default 200)\n");
1449	printf("	[-r N] Number of repetitions per thread (default 5000)\n");
1450	printf("	[-d] Disable rseq system call (no initialization)\n");
1451	printf("	[-D M] Disable rseq for each M threads\n");
1452	printf("	[-T test] Choose test: (s)pinlock, (l)ist, (b)uffer, (m)emcpy, (i)ncrement, membarrie(r)\n");
1453	printf("	[-M] Push into buffer and memcpy buffer with memory barriers.\n");
1454	printf("	[-v] Verbose output.\n");
1455	printf("	[-h] Show this help.\n");
1456	printf("\n");
1457}
1458
1459int main(int argc, char **argv)
1460{
1461	int i;
1462
1463	for (i = 1; i < argc; i++) {
1464		if (argv[i][0] != '-')
1465			continue;
1466		switch (argv[i][1]) {
1467		case '1':
1468		case '2':
1469		case '3':
1470		case '4':
1471		case '5':
1472		case '6':
1473		case '7':
1474		case '8':
1475		case '9':
1476			if (argc < i + 2) {
1477				show_usage(argc, argv);
1478				goto error;
1479			}
1480			loop_cnt[argv[i][1] - '0'] = atol(argv[i + 1]);
1481			i++;
1482			break;
1483		case 'm':
1484			if (argc < i + 2) {
1485				show_usage(argc, argv);
1486				goto error;
1487			}
1488			opt_modulo = atol(argv[i + 1]);
1489			if (opt_modulo < 0) {
1490				show_usage(argc, argv);
1491				goto error;
1492			}
1493			i++;
1494			break;
1495		case 's':
1496			if (argc < i + 2) {
1497				show_usage(argc, argv);
1498				goto error;
1499			}
1500			opt_sleep = atol(argv[i + 1]);
1501			if (opt_sleep < 0) {
1502				show_usage(argc, argv);
1503				goto error;
1504			}
1505			i++;
1506			break;
1507		case 'y':
1508			opt_yield = 1;
1509			break;
1510		case 'k':
1511			opt_signal = 1;
1512			break;
1513		case 'd':
1514			opt_disable_rseq = 1;
1515			break;
1516		case 'D':
1517			if (argc < i + 2) {
1518				show_usage(argc, argv);
1519				goto error;
1520			}
1521			opt_disable_mod = atol(argv[i + 1]);
1522			if (opt_disable_mod < 0) {
1523				show_usage(argc, argv);
1524				goto error;
1525			}
1526			i++;
1527			break;
1528		case 't':
1529			if (argc < i + 2) {
1530				show_usage(argc, argv);
1531				goto error;
1532			}
1533			opt_threads = atol(argv[i + 1]);
1534			if (opt_threads < 0) {
1535				show_usage(argc, argv);
1536				goto error;
1537			}
1538			i++;
1539			break;
1540		case 'r':
1541			if (argc < i + 2) {
1542				show_usage(argc, argv);
1543				goto error;
1544			}
1545			opt_reps = atoll(argv[i + 1]);
1546			if (opt_reps < 0) {
1547				show_usage(argc, argv);
1548				goto error;
1549			}
1550			i++;
1551			break;
1552		case 'h':
1553			show_usage(argc, argv);
1554			goto end;
1555		case 'T':
1556			if (argc < i + 2) {
1557				show_usage(argc, argv);
1558				goto error;
1559			}
1560			opt_test = *argv[i + 1];
1561			switch (opt_test) {
1562			case 's':
1563			case 'l':
1564			case 'i':
1565			case 'b':
1566			case 'm':
1567			case 'r':
1568				break;
1569			default:
1570				show_usage(argc, argv);
1571				goto error;
1572			}
1573			i++;
1574			break;
1575		case 'v':
1576			verbose = 1;
1577			break;
1578		case 'M':
1579			opt_mo = RSEQ_MO_RELEASE;
1580			break;
1581		default:
1582			show_usage(argc, argv);
1583			goto error;
1584		}
1585	}
1586
1587	loop_cnt_1 = loop_cnt[1];
1588	loop_cnt_2 = loop_cnt[2];
1589	loop_cnt_3 = loop_cnt[3];
1590	loop_cnt_4 = loop_cnt[4];
1591	loop_cnt_5 = loop_cnt[5];
1592	loop_cnt_6 = loop_cnt[6];
1593
1594	if (set_signal_handler())
1595		goto error;
1596
1597	if (!opt_disable_rseq && rseq_register_current_thread())
1598		goto error;
1599	if (!opt_disable_rseq && !rseq_validate_cpu_id()) {
1600		fprintf(stderr, "Error: cpu id getter unavailable\n");
1601		goto error;
1602	}
1603	switch (opt_test) {
1604	case 's':
1605		printf_verbose("spinlock\n");
1606		test_percpu_spinlock();
1607		break;
1608	case 'l':
1609		printf_verbose("linked list\n");
1610		test_percpu_list();
1611		break;
1612	case 'b':
1613		printf_verbose("buffer\n");
1614		test_percpu_buffer();
1615		break;
1616	case 'm':
1617		printf_verbose("memcpy buffer\n");
1618		test_percpu_memcpy_buffer();
1619		break;
1620	case 'i':
1621		printf_verbose("counter increment\n");
1622		test_percpu_inc();
1623		break;
1624	case 'r':
1625		printf_verbose("membarrier\n");
1626		test_membarrier();
1627		break;
1628	}
1629	if (!opt_disable_rseq && rseq_unregister_current_thread())
1630		abort();
1631end:
1632	return 0;
1633
1634error:
1635	return -1;
1636}
v5.4
   1// SPDX-License-Identifier: LGPL-2.1
   2#define _GNU_SOURCE
   3#include <assert.h>
 
   4#include <pthread.h>
   5#include <sched.h>
 
   6#include <stdint.h>
   7#include <stdio.h>
   8#include <stdlib.h>
   9#include <string.h>
  10#include <syscall.h>
  11#include <unistd.h>
  12#include <poll.h>
  13#include <sys/types.h>
  14#include <signal.h>
  15#include <errno.h>
  16#include <stddef.h>
 
  17
  18static inline pid_t gettid(void)
  19{
  20	return syscall(__NR_gettid);
  21}
  22
  23#define NR_INJECT	9
  24static int loop_cnt[NR_INJECT + 1];
  25
  26static int loop_cnt_1 asm("asm_loop_cnt_1") __attribute__((used));
  27static int loop_cnt_2 asm("asm_loop_cnt_2") __attribute__((used));
  28static int loop_cnt_3 asm("asm_loop_cnt_3") __attribute__((used));
  29static int loop_cnt_4 asm("asm_loop_cnt_4") __attribute__((used));
  30static int loop_cnt_5 asm("asm_loop_cnt_5") __attribute__((used));
  31static int loop_cnt_6 asm("asm_loop_cnt_6") __attribute__((used));
  32
  33static int opt_modulo, verbose;
  34
  35static int opt_yield, opt_signal, opt_sleep,
  36		opt_disable_rseq, opt_threads = 200,
  37		opt_disable_mod = 0, opt_test = 's', opt_mb = 0;
  38
  39#ifndef RSEQ_SKIP_FASTPATH
  40static long long opt_reps = 5000;
  41#else
  42static long long opt_reps = 100;
  43#endif
  44
  45static __thread __attribute__((tls_model("initial-exec")))
  46unsigned int signals_delivered;
  47
  48#ifndef BENCHMARK
  49
  50static __thread __attribute__((tls_model("initial-exec"), unused))
  51unsigned int yield_mod_cnt, nr_abort;
  52
  53#define printf_verbose(fmt, ...)			\
  54	do {						\
  55		if (verbose)				\
  56			printf(fmt, ## __VA_ARGS__);	\
  57	} while (0)
  58
  59#ifdef __i386__
  60
  61#define INJECT_ASM_REG	"eax"
  62
  63#define RSEQ_INJECT_CLOBBER \
  64	, INJECT_ASM_REG
  65
  66#define RSEQ_INJECT_ASM(n) \
  67	"mov asm_loop_cnt_" #n ", %%" INJECT_ASM_REG "\n\t" \
  68	"test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
  69	"jz 333f\n\t" \
  70	"222:\n\t" \
  71	"dec %%" INJECT_ASM_REG "\n\t" \
  72	"jnz 222b\n\t" \
  73	"333:\n\t"
  74
  75#elif defined(__x86_64__)
  76
  77#define INJECT_ASM_REG_P	"rax"
  78#define INJECT_ASM_REG		"eax"
  79
  80#define RSEQ_INJECT_CLOBBER \
  81	, INJECT_ASM_REG_P \
  82	, INJECT_ASM_REG
  83
  84#define RSEQ_INJECT_ASM(n) \
  85	"lea asm_loop_cnt_" #n "(%%rip), %%" INJECT_ASM_REG_P "\n\t" \
  86	"mov (%%" INJECT_ASM_REG_P "), %%" INJECT_ASM_REG "\n\t" \
  87	"test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
  88	"jz 333f\n\t" \
  89	"222:\n\t" \
  90	"dec %%" INJECT_ASM_REG "\n\t" \
  91	"jnz 222b\n\t" \
  92	"333:\n\t"
  93
  94#elif defined(__s390__)
  95
  96#define RSEQ_INJECT_INPUT \
  97	, [loop_cnt_1]"m"(loop_cnt[1]) \
  98	, [loop_cnt_2]"m"(loop_cnt[2]) \
  99	, [loop_cnt_3]"m"(loop_cnt[3]) \
 100	, [loop_cnt_4]"m"(loop_cnt[4]) \
 101	, [loop_cnt_5]"m"(loop_cnt[5]) \
 102	, [loop_cnt_6]"m"(loop_cnt[6])
 103
 104#define INJECT_ASM_REG	"r12"
 105
 106#define RSEQ_INJECT_CLOBBER \
 107	, INJECT_ASM_REG
 108
 109#define RSEQ_INJECT_ASM(n) \
 110	"l %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 111	"ltr %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG "\n\t" \
 112	"je 333f\n\t" \
 113	"222:\n\t" \
 114	"ahi %%" INJECT_ASM_REG ", -1\n\t" \
 115	"jnz 222b\n\t" \
 116	"333:\n\t"
 117
 118#elif defined(__ARMEL__)
 119
 120#define RSEQ_INJECT_INPUT \
 121	, [loop_cnt_1]"m"(loop_cnt[1]) \
 122	, [loop_cnt_2]"m"(loop_cnt[2]) \
 123	, [loop_cnt_3]"m"(loop_cnt[3]) \
 124	, [loop_cnt_4]"m"(loop_cnt[4]) \
 125	, [loop_cnt_5]"m"(loop_cnt[5]) \
 126	, [loop_cnt_6]"m"(loop_cnt[6])
 127
 128#define INJECT_ASM_REG	"r4"
 129
 130#define RSEQ_INJECT_CLOBBER \
 131	, INJECT_ASM_REG
 132
 133#define RSEQ_INJECT_ASM(n) \
 134	"ldr " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 135	"cmp " INJECT_ASM_REG ", #0\n\t" \
 136	"beq 333f\n\t" \
 137	"222:\n\t" \
 138	"subs " INJECT_ASM_REG ", #1\n\t" \
 139	"bne 222b\n\t" \
 140	"333:\n\t"
 141
 142#elif defined(__AARCH64EL__)
 143
 144#define RSEQ_INJECT_INPUT \
 145	, [loop_cnt_1] "Qo" (loop_cnt[1]) \
 146	, [loop_cnt_2] "Qo" (loop_cnt[2]) \
 147	, [loop_cnt_3] "Qo" (loop_cnt[3]) \
 148	, [loop_cnt_4] "Qo" (loop_cnt[4]) \
 149	, [loop_cnt_5] "Qo" (loop_cnt[5]) \
 150	, [loop_cnt_6] "Qo" (loop_cnt[6])
 151
 152#define INJECT_ASM_REG	RSEQ_ASM_TMP_REG32
 153
 154#define RSEQ_INJECT_ASM(n) \
 155	"	ldr	" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n"	\
 156	"	cbz	" INJECT_ASM_REG ", 333f\n"			\
 157	"222:\n"							\
 158	"	sub	" INJECT_ASM_REG ", " INJECT_ASM_REG ", #1\n"	\
 159	"	cbnz	" INJECT_ASM_REG ", 222b\n"			\
 160	"333:\n"
 161
 162#elif __PPC__
 163
 164#define RSEQ_INJECT_INPUT \
 165	, [loop_cnt_1]"m"(loop_cnt[1]) \
 166	, [loop_cnt_2]"m"(loop_cnt[2]) \
 167	, [loop_cnt_3]"m"(loop_cnt[3]) \
 168	, [loop_cnt_4]"m"(loop_cnt[4]) \
 169	, [loop_cnt_5]"m"(loop_cnt[5]) \
 170	, [loop_cnt_6]"m"(loop_cnt[6])
 171
 172#define INJECT_ASM_REG	"r18"
 173
 174#define RSEQ_INJECT_CLOBBER \
 175	, INJECT_ASM_REG
 176
 177#define RSEQ_INJECT_ASM(n) \
 178	"lwz %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 179	"cmpwi %%" INJECT_ASM_REG ", 0\n\t" \
 180	"beq 333f\n\t" \
 181	"222:\n\t" \
 182	"subic. %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG ", 1\n\t" \
 183	"bne 222b\n\t" \
 184	"333:\n\t"
 185
 186#elif defined(__mips__)
 187
 188#define RSEQ_INJECT_INPUT \
 189	, [loop_cnt_1]"m"(loop_cnt[1]) \
 190	, [loop_cnt_2]"m"(loop_cnt[2]) \
 191	, [loop_cnt_3]"m"(loop_cnt[3]) \
 192	, [loop_cnt_4]"m"(loop_cnt[4]) \
 193	, [loop_cnt_5]"m"(loop_cnt[5]) \
 194	, [loop_cnt_6]"m"(loop_cnt[6])
 195
 196#define INJECT_ASM_REG	"$5"
 197
 198#define RSEQ_INJECT_CLOBBER \
 199	, INJECT_ASM_REG
 200
 201#define RSEQ_INJECT_ASM(n) \
 202	"lw " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
 203	"beqz " INJECT_ASM_REG ", 333f\n\t" \
 204	"222:\n\t" \
 205	"addiu " INJECT_ASM_REG ", -1\n\t" \
 206	"bnez " INJECT_ASM_REG ", 222b\n\t" \
 207	"333:\n\t"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 208
 209#else
 210#error unsupported target
 211#endif
 212
 213#define RSEQ_INJECT_FAILED \
 214	nr_abort++;
 215
 216#define RSEQ_INJECT_C(n) \
 217{ \
 218	int loc_i, loc_nr_loops = loop_cnt[n]; \
 219	\
 220	for (loc_i = 0; loc_i < loc_nr_loops; loc_i++) { \
 221		rseq_barrier(); \
 222	} \
 223	if (loc_nr_loops == -1 && opt_modulo) { \
 224		if (yield_mod_cnt == opt_modulo - 1) { \
 225			if (opt_sleep > 0) \
 226				poll(NULL, 0, opt_sleep); \
 227			if (opt_yield) \
 228				sched_yield(); \
 229			if (opt_signal) \
 230				raise(SIGUSR1); \
 231			yield_mod_cnt = 0; \
 232		} else { \
 233			yield_mod_cnt++; \
 234		} \
 235	} \
 236}
 237
 238#else
 239
 240#define printf_verbose(fmt, ...)
 241
 242#endif /* BENCHMARK */
 243
 244#include "rseq.h"
 245
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 246struct percpu_lock_entry {
 247	intptr_t v;
 248} __attribute__((aligned(128)));
 249
 250struct percpu_lock {
 251	struct percpu_lock_entry c[CPU_SETSIZE];
 252};
 253
 254struct test_data_entry {
 255	intptr_t count;
 256} __attribute__((aligned(128)));
 257
 258struct spinlock_test_data {
 259	struct percpu_lock lock;
 260	struct test_data_entry c[CPU_SETSIZE];
 261};
 262
 263struct spinlock_thread_test_data {
 264	struct spinlock_test_data *data;
 265	long long reps;
 266	int reg;
 267};
 268
 269struct inc_test_data {
 270	struct test_data_entry c[CPU_SETSIZE];
 271};
 272
 273struct inc_thread_test_data {
 274	struct inc_test_data *data;
 275	long long reps;
 276	int reg;
 277};
 278
 279struct percpu_list_node {
 280	intptr_t data;
 281	struct percpu_list_node *next;
 282};
 283
 284struct percpu_list_entry {
 285	struct percpu_list_node *head;
 286} __attribute__((aligned(128)));
 287
 288struct percpu_list {
 289	struct percpu_list_entry c[CPU_SETSIZE];
 290};
 291
 292#define BUFFER_ITEM_PER_CPU	100
 293
 294struct percpu_buffer_node {
 295	intptr_t data;
 296};
 297
 298struct percpu_buffer_entry {
 299	intptr_t offset;
 300	intptr_t buflen;
 301	struct percpu_buffer_node **array;
 302} __attribute__((aligned(128)));
 303
 304struct percpu_buffer {
 305	struct percpu_buffer_entry c[CPU_SETSIZE];
 306};
 307
 308#define MEMCPY_BUFFER_ITEM_PER_CPU	100
 309
 310struct percpu_memcpy_buffer_node {
 311	intptr_t data1;
 312	uint64_t data2;
 313};
 314
 315struct percpu_memcpy_buffer_entry {
 316	intptr_t offset;
 317	intptr_t buflen;
 318	struct percpu_memcpy_buffer_node *array;
 319} __attribute__((aligned(128)));
 320
 321struct percpu_memcpy_buffer {
 322	struct percpu_memcpy_buffer_entry c[CPU_SETSIZE];
 323};
 324
 325/* A simple percpu spinlock. Grabs lock on current cpu. */
 326static int rseq_this_cpu_lock(struct percpu_lock *lock)
 327{
 328	int cpu;
 329
 330	for (;;) {
 331		int ret;
 332
 333		cpu = rseq_cpu_start();
 334		ret = rseq_cmpeqv_storev(&lock->c[cpu].v,
 
 
 
 
 
 
 335					 0, 1, cpu);
 336		if (rseq_likely(!ret))
 337			break;
 338		/* Retry if comparison fails or rseq aborts. */
 339	}
 340	/*
 341	 * Acquire semantic when taking lock after control dependency.
 342	 * Matches rseq_smp_store_release().
 343	 */
 344	rseq_smp_acquire__after_ctrl_dep();
 345	return cpu;
 346}
 347
 348static void rseq_percpu_unlock(struct percpu_lock *lock, int cpu)
 349{
 350	assert(lock->c[cpu].v == 1);
 351	/*
 352	 * Release lock, with release semantic. Matches
 353	 * rseq_smp_acquire__after_ctrl_dep().
 354	 */
 355	rseq_smp_store_release(&lock->c[cpu].v, 0);
 356}
 357
 358void *test_percpu_spinlock_thread(void *arg)
 359{
 360	struct spinlock_thread_test_data *thread_data = arg;
 361	struct spinlock_test_data *data = thread_data->data;
 362	long long i, reps;
 363
 364	if (!opt_disable_rseq && thread_data->reg &&
 365	    rseq_register_current_thread())
 366		abort();
 367	reps = thread_data->reps;
 368	for (i = 0; i < reps; i++) {
 369		int cpu = rseq_cpu_start();
 370
 371		cpu = rseq_this_cpu_lock(&data->lock);
 372		data->c[cpu].count++;
 373		rseq_percpu_unlock(&data->lock, cpu);
 374#ifndef BENCHMARK
 375		if (i != 0 && !(i % (reps / 10)))
 376			printf_verbose("tid %d: count %lld\n", (int) gettid(), i);
 
 377#endif
 378	}
 379	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 380		       (int) gettid(), nr_abort, signals_delivered);
 381	if (!opt_disable_rseq && thread_data->reg &&
 382	    rseq_unregister_current_thread())
 383		abort();
 384	return NULL;
 385}
 386
 387/*
 388 * A simple test which implements a sharded counter using a per-cpu
 389 * lock.  Obviously real applications might prefer to simply use a
 390 * per-cpu increment; however, this is reasonable for a test and the
 391 * lock can be extended to synchronize more complicated operations.
 392 */
 393void test_percpu_spinlock(void)
 394{
 395	const int num_threads = opt_threads;
 396	int i, ret;
 397	uint64_t sum;
 398	pthread_t test_threads[num_threads];
 399	struct spinlock_test_data data;
 400	struct spinlock_thread_test_data thread_data[num_threads];
 401
 402	memset(&data, 0, sizeof(data));
 403	for (i = 0; i < num_threads; i++) {
 404		thread_data[i].reps = opt_reps;
 405		if (opt_disable_mod <= 0 || (i % opt_disable_mod))
 406			thread_data[i].reg = 1;
 407		else
 408			thread_data[i].reg = 0;
 409		thread_data[i].data = &data;
 410		ret = pthread_create(&test_threads[i], NULL,
 411				     test_percpu_spinlock_thread,
 412				     &thread_data[i]);
 413		if (ret) {
 414			errno = ret;
 415			perror("pthread_create");
 416			abort();
 417		}
 418	}
 419
 420	for (i = 0; i < num_threads; i++) {
 421		ret = pthread_join(test_threads[i], NULL);
 422		if (ret) {
 423			errno = ret;
 424			perror("pthread_join");
 425			abort();
 426		}
 427	}
 428
 429	sum = 0;
 430	for (i = 0; i < CPU_SETSIZE; i++)
 431		sum += data.c[i].count;
 432
 433	assert(sum == (uint64_t)opt_reps * num_threads);
 434}
 435
 436void *test_percpu_inc_thread(void *arg)
 437{
 438	struct inc_thread_test_data *thread_data = arg;
 439	struct inc_test_data *data = thread_data->data;
 440	long long i, reps;
 441
 442	if (!opt_disable_rseq && thread_data->reg &&
 443	    rseq_register_current_thread())
 444		abort();
 445	reps = thread_data->reps;
 446	for (i = 0; i < reps; i++) {
 447		int ret;
 448
 449		do {
 450			int cpu;
 451
 452			cpu = rseq_cpu_start();
 453			ret = rseq_addv(&data->c[cpu].count, 1, cpu);
 
 454		} while (rseq_unlikely(ret));
 455#ifndef BENCHMARK
 456		if (i != 0 && !(i % (reps / 10)))
 457			printf_verbose("tid %d: count %lld\n", (int) gettid(), i);
 
 458#endif
 459	}
 460	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 461		       (int) gettid(), nr_abort, signals_delivered);
 462	if (!opt_disable_rseq && thread_data->reg &&
 463	    rseq_unregister_current_thread())
 464		abort();
 465	return NULL;
 466}
 467
 468void test_percpu_inc(void)
 469{
 470	const int num_threads = opt_threads;
 471	int i, ret;
 472	uint64_t sum;
 473	pthread_t test_threads[num_threads];
 474	struct inc_test_data data;
 475	struct inc_thread_test_data thread_data[num_threads];
 476
 477	memset(&data, 0, sizeof(data));
 478	for (i = 0; i < num_threads; i++) {
 479		thread_data[i].reps = opt_reps;
 480		if (opt_disable_mod <= 0 || (i % opt_disable_mod))
 481			thread_data[i].reg = 1;
 482		else
 483			thread_data[i].reg = 0;
 484		thread_data[i].data = &data;
 485		ret = pthread_create(&test_threads[i], NULL,
 486				     test_percpu_inc_thread,
 487				     &thread_data[i]);
 488		if (ret) {
 489			errno = ret;
 490			perror("pthread_create");
 491			abort();
 492		}
 493	}
 494
 495	for (i = 0; i < num_threads; i++) {
 496		ret = pthread_join(test_threads[i], NULL);
 497		if (ret) {
 498			errno = ret;
 499			perror("pthread_join");
 500			abort();
 501		}
 502	}
 503
 504	sum = 0;
 505	for (i = 0; i < CPU_SETSIZE; i++)
 506		sum += data.c[i].count;
 507
 508	assert(sum == (uint64_t)opt_reps * num_threads);
 509}
 510
 511void this_cpu_list_push(struct percpu_list *list,
 512			struct percpu_list_node *node,
 513			int *_cpu)
 514{
 515	int cpu;
 516
 517	for (;;) {
 518		intptr_t *targetptr, newval, expect;
 519		int ret;
 520
 521		cpu = rseq_cpu_start();
 522		/* Load list->c[cpu].head with single-copy atomicity. */
 523		expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head);
 524		newval = (intptr_t)node;
 525		targetptr = (intptr_t *)&list->c[cpu].head;
 526		node->next = (struct percpu_list_node *)expect;
 527		ret = rseq_cmpeqv_storev(targetptr, expect, newval, cpu);
 
 528		if (rseq_likely(!ret))
 529			break;
 530		/* Retry if comparison fails or rseq aborts. */
 531	}
 532	if (_cpu)
 533		*_cpu = cpu;
 534}
 535
 536/*
 537 * Unlike a traditional lock-less linked list; the availability of a
 538 * rseq primitive allows us to implement pop without concerns over
 539 * ABA-type races.
 540 */
 541struct percpu_list_node *this_cpu_list_pop(struct percpu_list *list,
 542					   int *_cpu)
 543{
 544	struct percpu_list_node *node = NULL;
 545	int cpu;
 546
 547	for (;;) {
 548		struct percpu_list_node *head;
 549		intptr_t *targetptr, expectnot, *load;
 550		off_t offset;
 551		int ret;
 552
 553		cpu = rseq_cpu_start();
 554		targetptr = (intptr_t *)&list->c[cpu].head;
 555		expectnot = (intptr_t)NULL;
 556		offset = offsetof(struct percpu_list_node, next);
 557		load = (intptr_t *)&head;
 558		ret = rseq_cmpnev_storeoffp_load(targetptr, expectnot,
 559						   offset, load, cpu);
 
 560		if (rseq_likely(!ret)) {
 561			node = head;
 562			break;
 563		}
 564		if (ret > 0)
 565			break;
 566		/* Retry if rseq aborts. */
 567	}
 568	if (_cpu)
 569		*_cpu = cpu;
 570	return node;
 571}
 572
 573/*
 574 * __percpu_list_pop is not safe against concurrent accesses. Should
 575 * only be used on lists that are not concurrently modified.
 576 */
 577struct percpu_list_node *__percpu_list_pop(struct percpu_list *list, int cpu)
 578{
 579	struct percpu_list_node *node;
 580
 581	node = list->c[cpu].head;
 582	if (!node)
 583		return NULL;
 584	list->c[cpu].head = node->next;
 585	return node;
 586}
 587
 588void *test_percpu_list_thread(void *arg)
 589{
 590	long long i, reps;
 591	struct percpu_list *list = (struct percpu_list *)arg;
 592
 593	if (!opt_disable_rseq && rseq_register_current_thread())
 594		abort();
 595
 596	reps = opt_reps;
 597	for (i = 0; i < reps; i++) {
 598		struct percpu_list_node *node;
 599
 600		node = this_cpu_list_pop(list, NULL);
 601		if (opt_yield)
 602			sched_yield();  /* encourage shuffling */
 603		if (node)
 604			this_cpu_list_push(list, node, NULL);
 605	}
 606
 607	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 608		       (int) gettid(), nr_abort, signals_delivered);
 609	if (!opt_disable_rseq && rseq_unregister_current_thread())
 610		abort();
 611
 612	return NULL;
 613}
 614
 615/* Simultaneous modification to a per-cpu linked list from many threads.  */
 616void test_percpu_list(void)
 617{
 618	const int num_threads = opt_threads;
 619	int i, j, ret;
 620	uint64_t sum = 0, expected_sum = 0;
 621	struct percpu_list list;
 622	pthread_t test_threads[num_threads];
 623	cpu_set_t allowed_cpus;
 624
 625	memset(&list, 0, sizeof(list));
 626
 627	/* Generate list entries for every usable cpu. */
 628	sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
 629	for (i = 0; i < CPU_SETSIZE; i++) {
 630		if (!CPU_ISSET(i, &allowed_cpus))
 631			continue;
 632		for (j = 1; j <= 100; j++) {
 633			struct percpu_list_node *node;
 634
 635			expected_sum += j;
 636
 637			node = malloc(sizeof(*node));
 638			assert(node);
 639			node->data = j;
 640			node->next = list.c[i].head;
 641			list.c[i].head = node;
 642		}
 643	}
 644
 645	for (i = 0; i < num_threads; i++) {
 646		ret = pthread_create(&test_threads[i], NULL,
 647				     test_percpu_list_thread, &list);
 648		if (ret) {
 649			errno = ret;
 650			perror("pthread_create");
 651			abort();
 652		}
 653	}
 654
 655	for (i = 0; i < num_threads; i++) {
 656		ret = pthread_join(test_threads[i], NULL);
 657		if (ret) {
 658			errno = ret;
 659			perror("pthread_join");
 660			abort();
 661		}
 662	}
 663
 664	for (i = 0; i < CPU_SETSIZE; i++) {
 665		struct percpu_list_node *node;
 666
 667		if (!CPU_ISSET(i, &allowed_cpus))
 668			continue;
 669
 670		while ((node = __percpu_list_pop(&list, i))) {
 671			sum += node->data;
 672			free(node);
 673		}
 674	}
 675
 676	/*
 677	 * All entries should now be accounted for (unless some external
 678	 * actor is interfering with our allowed affinity while this
 679	 * test is running).
 680	 */
 681	assert(sum == expected_sum);
 682}
 683
 684bool this_cpu_buffer_push(struct percpu_buffer *buffer,
 685			  struct percpu_buffer_node *node,
 686			  int *_cpu)
 687{
 688	bool result = false;
 689	int cpu;
 690
 691	for (;;) {
 692		intptr_t *targetptr_spec, newval_spec;
 693		intptr_t *targetptr_final, newval_final;
 694		intptr_t offset;
 695		int ret;
 696
 697		cpu = rseq_cpu_start();
 698		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 699		if (offset == buffer->c[cpu].buflen)
 700			break;
 701		newval_spec = (intptr_t)node;
 702		targetptr_spec = (intptr_t *)&buffer->c[cpu].array[offset];
 703		newval_final = offset + 1;
 704		targetptr_final = &buffer->c[cpu].offset;
 705		if (opt_mb)
 706			ret = rseq_cmpeqv_trystorev_storev_release(
 707				targetptr_final, offset, targetptr_spec,
 708				newval_spec, newval_final, cpu);
 709		else
 710			ret = rseq_cmpeqv_trystorev_storev(targetptr_final,
 711				offset, targetptr_spec, newval_spec,
 712				newval_final, cpu);
 713		if (rseq_likely(!ret)) {
 714			result = true;
 715			break;
 716		}
 717		/* Retry if comparison fails or rseq aborts. */
 718	}
 719	if (_cpu)
 720		*_cpu = cpu;
 721	return result;
 722}
 723
 724struct percpu_buffer_node *this_cpu_buffer_pop(struct percpu_buffer *buffer,
 725					       int *_cpu)
 726{
 727	struct percpu_buffer_node *head;
 728	int cpu;
 729
 730	for (;;) {
 731		intptr_t *targetptr, newval;
 732		intptr_t offset;
 733		int ret;
 734
 735		cpu = rseq_cpu_start();
 736		/* Load offset with single-copy atomicity. */
 737		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 738		if (offset == 0) {
 739			head = NULL;
 740			break;
 741		}
 742		head = RSEQ_READ_ONCE(buffer->c[cpu].array[offset - 1]);
 743		newval = offset - 1;
 744		targetptr = (intptr_t *)&buffer->c[cpu].offset;
 745		ret = rseq_cmpeqv_cmpeqv_storev(targetptr, offset,
 
 746			(intptr_t *)&buffer->c[cpu].array[offset - 1],
 747			(intptr_t)head, newval, cpu);
 748		if (rseq_likely(!ret))
 749			break;
 750		/* Retry if comparison fails or rseq aborts. */
 751	}
 752	if (_cpu)
 753		*_cpu = cpu;
 754	return head;
 755}
 756
 757/*
 758 * __percpu_buffer_pop is not safe against concurrent accesses. Should
 759 * only be used on buffers that are not concurrently modified.
 760 */
 761struct percpu_buffer_node *__percpu_buffer_pop(struct percpu_buffer *buffer,
 762					       int cpu)
 763{
 764	struct percpu_buffer_node *head;
 765	intptr_t offset;
 766
 767	offset = buffer->c[cpu].offset;
 768	if (offset == 0)
 769		return NULL;
 770	head = buffer->c[cpu].array[offset - 1];
 771	buffer->c[cpu].offset = offset - 1;
 772	return head;
 773}
 774
 775void *test_percpu_buffer_thread(void *arg)
 776{
 777	long long i, reps;
 778	struct percpu_buffer *buffer = (struct percpu_buffer *)arg;
 779
 780	if (!opt_disable_rseq && rseq_register_current_thread())
 781		abort();
 782
 783	reps = opt_reps;
 784	for (i = 0; i < reps; i++) {
 785		struct percpu_buffer_node *node;
 786
 787		node = this_cpu_buffer_pop(buffer, NULL);
 788		if (opt_yield)
 789			sched_yield();  /* encourage shuffling */
 790		if (node) {
 791			if (!this_cpu_buffer_push(buffer, node, NULL)) {
 792				/* Should increase buffer size. */
 793				abort();
 794			}
 795		}
 796	}
 797
 798	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
 799		       (int) gettid(), nr_abort, signals_delivered);
 800	if (!opt_disable_rseq && rseq_unregister_current_thread())
 801		abort();
 802
 803	return NULL;
 804}
 805
 806/* Simultaneous modification to a per-cpu buffer from many threads.  */
 807void test_percpu_buffer(void)
 808{
 809	const int num_threads = opt_threads;
 810	int i, j, ret;
 811	uint64_t sum = 0, expected_sum = 0;
 812	struct percpu_buffer buffer;
 813	pthread_t test_threads[num_threads];
 814	cpu_set_t allowed_cpus;
 815
 816	memset(&buffer, 0, sizeof(buffer));
 817
 818	/* Generate list entries for every usable cpu. */
 819	sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
 820	for (i = 0; i < CPU_SETSIZE; i++) {
 821		if (!CPU_ISSET(i, &allowed_cpus))
 822			continue;
 823		/* Worse-case is every item in same CPU. */
 824		buffer.c[i].array =
 825			malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE *
 826			       BUFFER_ITEM_PER_CPU);
 827		assert(buffer.c[i].array);
 828		buffer.c[i].buflen = CPU_SETSIZE * BUFFER_ITEM_PER_CPU;
 829		for (j = 1; j <= BUFFER_ITEM_PER_CPU; j++) {
 830			struct percpu_buffer_node *node;
 831
 832			expected_sum += j;
 833
 834			/*
 835			 * We could theoretically put the word-sized
 836			 * "data" directly in the buffer. However, we
 837			 * want to model objects that would not fit
 838			 * within a single word, so allocate an object
 839			 * for each node.
 840			 */
 841			node = malloc(sizeof(*node));
 842			assert(node);
 843			node->data = j;
 844			buffer.c[i].array[j - 1] = node;
 845			buffer.c[i].offset++;
 846		}
 847	}
 848
 849	for (i = 0; i < num_threads; i++) {
 850		ret = pthread_create(&test_threads[i], NULL,
 851				     test_percpu_buffer_thread, &buffer);
 852		if (ret) {
 853			errno = ret;
 854			perror("pthread_create");
 855			abort();
 856		}
 857	}
 858
 859	for (i = 0; i < num_threads; i++) {
 860		ret = pthread_join(test_threads[i], NULL);
 861		if (ret) {
 862			errno = ret;
 863			perror("pthread_join");
 864			abort();
 865		}
 866	}
 867
 868	for (i = 0; i < CPU_SETSIZE; i++) {
 869		struct percpu_buffer_node *node;
 870
 871		if (!CPU_ISSET(i, &allowed_cpus))
 872			continue;
 873
 874		while ((node = __percpu_buffer_pop(&buffer, i))) {
 875			sum += node->data;
 876			free(node);
 877		}
 878		free(buffer.c[i].array);
 879	}
 880
 881	/*
 882	 * All entries should now be accounted for (unless some external
 883	 * actor is interfering with our allowed affinity while this
 884	 * test is running).
 885	 */
 886	assert(sum == expected_sum);
 887}
 888
 889bool this_cpu_memcpy_buffer_push(struct percpu_memcpy_buffer *buffer,
 890				 struct percpu_memcpy_buffer_node item,
 891				 int *_cpu)
 892{
 893	bool result = false;
 894	int cpu;
 895
 896	for (;;) {
 897		intptr_t *targetptr_final, newval_final, offset;
 898		char *destptr, *srcptr;
 899		size_t copylen;
 900		int ret;
 901
 902		cpu = rseq_cpu_start();
 903		/* Load offset with single-copy atomicity. */
 904		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 905		if (offset == buffer->c[cpu].buflen)
 906			break;
 907		destptr = (char *)&buffer->c[cpu].array[offset];
 908		srcptr = (char *)&item;
 909		/* copylen must be <= 4kB. */
 910		copylen = sizeof(item);
 911		newval_final = offset + 1;
 912		targetptr_final = &buffer->c[cpu].offset;
 913		if (opt_mb)
 914			ret = rseq_cmpeqv_trymemcpy_storev_release(
 915				targetptr_final, offset,
 916				destptr, srcptr, copylen,
 917				newval_final, cpu);
 918		else
 919			ret = rseq_cmpeqv_trymemcpy_storev(targetptr_final,
 920				offset, destptr, srcptr, copylen,
 921				newval_final, cpu);
 922		if (rseq_likely(!ret)) {
 923			result = true;
 924			break;
 925		}
 926		/* Retry if comparison fails or rseq aborts. */
 927	}
 928	if (_cpu)
 929		*_cpu = cpu;
 930	return result;
 931}
 932
 933bool this_cpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer,
 934				struct percpu_memcpy_buffer_node *item,
 935				int *_cpu)
 936{
 937	bool result = false;
 938	int cpu;
 939
 940	for (;;) {
 941		intptr_t *targetptr_final, newval_final, offset;
 942		char *destptr, *srcptr;
 943		size_t copylen;
 944		int ret;
 945
 946		cpu = rseq_cpu_start();
 947		/* Load offset with single-copy atomicity. */
 948		offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
 949		if (offset == 0)
 950			break;
 951		destptr = (char *)item;
 952		srcptr = (char *)&buffer->c[cpu].array[offset - 1];
 953		/* copylen must be <= 4kB. */
 954		copylen = sizeof(*item);
 955		newval_final = offset - 1;
 956		targetptr_final = &buffer->c[cpu].offset;
 957		ret = rseq_cmpeqv_trymemcpy_storev(targetptr_final,
 958			offset, destptr, srcptr, copylen,
 959			newval_final, cpu);
 960		if (rseq_likely(!ret)) {
 961			result = true;
 962			break;
 963		}
 964		/* Retry if comparison fails or rseq aborts. */
 965	}
 966	if (_cpu)
 967		*_cpu = cpu;
 968	return result;
 969}
 970
 971/*
 972 * __percpu_memcpy_buffer_pop is not safe against concurrent accesses. Should
 973 * only be used on buffers that are not concurrently modified.
 974 */
 975bool __percpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer,
 976				struct percpu_memcpy_buffer_node *item,
 977				int cpu)
 978{
 979	intptr_t offset;
 980
 981	offset = buffer->c[cpu].offset;
 982	if (offset == 0)
 983		return false;
 984	memcpy(item, &buffer->c[cpu].array[offset - 1], sizeof(*item));
 985	buffer->c[cpu].offset = offset - 1;
 986	return true;
 987}
 988
 989void *test_percpu_memcpy_buffer_thread(void *arg)
 990{
 991	long long i, reps;
 992	struct percpu_memcpy_buffer *buffer = (struct percpu_memcpy_buffer *)arg;
 993
 994	if (!opt_disable_rseq && rseq_register_current_thread())
 995		abort();
 996
 997	reps = opt_reps;
 998	for (i = 0; i < reps; i++) {
 999		struct percpu_memcpy_buffer_node item;
1000		bool result;
1001
1002		result = this_cpu_memcpy_buffer_pop(buffer, &item, NULL);
1003		if (opt_yield)
1004			sched_yield();  /* encourage shuffling */
1005		if (result) {
1006			if (!this_cpu_memcpy_buffer_push(buffer, item, NULL)) {
1007				/* Should increase buffer size. */
1008				abort();
1009			}
1010		}
1011	}
1012
1013	printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
1014		       (int) gettid(), nr_abort, signals_delivered);
1015	if (!opt_disable_rseq && rseq_unregister_current_thread())
1016		abort();
1017
1018	return NULL;
1019}
1020
1021/* Simultaneous modification to a per-cpu buffer from many threads.  */
1022void test_percpu_memcpy_buffer(void)
1023{
1024	const int num_threads = opt_threads;
1025	int i, j, ret;
1026	uint64_t sum = 0, expected_sum = 0;
1027	struct percpu_memcpy_buffer buffer;
1028	pthread_t test_threads[num_threads];
1029	cpu_set_t allowed_cpus;
1030
1031	memset(&buffer, 0, sizeof(buffer));
1032
1033	/* Generate list entries for every usable cpu. */
1034	sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
1035	for (i = 0; i < CPU_SETSIZE; i++) {
1036		if (!CPU_ISSET(i, &allowed_cpus))
1037			continue;
1038		/* Worse-case is every item in same CPU. */
1039		buffer.c[i].array =
1040			malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE *
1041			       MEMCPY_BUFFER_ITEM_PER_CPU);
1042		assert(buffer.c[i].array);
1043		buffer.c[i].buflen = CPU_SETSIZE * MEMCPY_BUFFER_ITEM_PER_CPU;
1044		for (j = 1; j <= MEMCPY_BUFFER_ITEM_PER_CPU; j++) {
1045			expected_sum += 2 * j + 1;
1046
1047			/*
1048			 * We could theoretically put the word-sized
1049			 * "data" directly in the buffer. However, we
1050			 * want to model objects that would not fit
1051			 * within a single word, so allocate an object
1052			 * for each node.
1053			 */
1054			buffer.c[i].array[j - 1].data1 = j;
1055			buffer.c[i].array[j - 1].data2 = j + 1;
1056			buffer.c[i].offset++;
1057		}
1058	}
1059
1060	for (i = 0; i < num_threads; i++) {
1061		ret = pthread_create(&test_threads[i], NULL,
1062				     test_percpu_memcpy_buffer_thread,
1063				     &buffer);
1064		if (ret) {
1065			errno = ret;
1066			perror("pthread_create");
1067			abort();
1068		}
1069	}
1070
1071	for (i = 0; i < num_threads; i++) {
1072		ret = pthread_join(test_threads[i], NULL);
1073		if (ret) {
1074			errno = ret;
1075			perror("pthread_join");
1076			abort();
1077		}
1078	}
1079
1080	for (i = 0; i < CPU_SETSIZE; i++) {
1081		struct percpu_memcpy_buffer_node item;
1082
1083		if (!CPU_ISSET(i, &allowed_cpus))
1084			continue;
1085
1086		while (__percpu_memcpy_buffer_pop(&buffer, &item, i)) {
1087			sum += item.data1;
1088			sum += item.data2;
1089		}
1090		free(buffer.c[i].array);
1091	}
1092
1093	/*
1094	 * All entries should now be accounted for (unless some external
1095	 * actor is interfering with our allowed affinity while this
1096	 * test is running).
1097	 */
1098	assert(sum == expected_sum);
1099}
1100
1101static void test_signal_interrupt_handler(int signo)
1102{
1103	signals_delivered++;
1104}
1105
1106static int set_signal_handler(void)
1107{
1108	int ret = 0;
1109	struct sigaction sa;
1110	sigset_t sigset;
1111
1112	ret = sigemptyset(&sigset);
1113	if (ret < 0) {
1114		perror("sigemptyset");
1115		return ret;
1116	}
1117
1118	sa.sa_handler = test_signal_interrupt_handler;
1119	sa.sa_mask = sigset;
1120	sa.sa_flags = 0;
1121	ret = sigaction(SIGUSR1, &sa, NULL);
1122	if (ret < 0) {
1123		perror("sigaction");
1124		return ret;
1125	}
1126
1127	printf_verbose("Signal handler set for SIGUSR1\n");
1128
1129	return ret;
1130}
1131
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1132static void show_usage(int argc, char **argv)
1133{
1134	printf("Usage : %s <OPTIONS>\n",
1135		argv[0]);
1136	printf("OPTIONS:\n");
1137	printf("	[-1 loops] Number of loops for delay injection 1\n");
1138	printf("	[-2 loops] Number of loops for delay injection 2\n");
1139	printf("	[-3 loops] Number of loops for delay injection 3\n");
1140	printf("	[-4 loops] Number of loops for delay injection 4\n");
1141	printf("	[-5 loops] Number of loops for delay injection 5\n");
1142	printf("	[-6 loops] Number of loops for delay injection 6\n");
1143	printf("	[-7 loops] Number of loops for delay injection 7 (-1 to enable -m)\n");
1144	printf("	[-8 loops] Number of loops for delay injection 8 (-1 to enable -m)\n");
1145	printf("	[-9 loops] Number of loops for delay injection 9 (-1 to enable -m)\n");
1146	printf("	[-m N] Yield/sleep/kill every modulo N (default 0: disabled) (>= 0)\n");
1147	printf("	[-y] Yield\n");
1148	printf("	[-k] Kill thread with signal\n");
1149	printf("	[-s S] S: =0: disabled (default), >0: sleep time (ms)\n");
1150	printf("	[-t N] Number of threads (default 200)\n");
1151	printf("	[-r N] Number of repetitions per thread (default 5000)\n");
1152	printf("	[-d] Disable rseq system call (no initialization)\n");
1153	printf("	[-D M] Disable rseq for each M threads\n");
1154	printf("	[-T test] Choose test: (s)pinlock, (l)ist, (b)uffer, (m)emcpy, (i)ncrement\n");
1155	printf("	[-M] Push into buffer and memcpy buffer with memory barriers.\n");
1156	printf("	[-v] Verbose output.\n");
1157	printf("	[-h] Show this help.\n");
1158	printf("\n");
1159}
1160
1161int main(int argc, char **argv)
1162{
1163	int i;
1164
1165	for (i = 1; i < argc; i++) {
1166		if (argv[i][0] != '-')
1167			continue;
1168		switch (argv[i][1]) {
1169		case '1':
1170		case '2':
1171		case '3':
1172		case '4':
1173		case '5':
1174		case '6':
1175		case '7':
1176		case '8':
1177		case '9':
1178			if (argc < i + 2) {
1179				show_usage(argc, argv);
1180				goto error;
1181			}
1182			loop_cnt[argv[i][1] - '0'] = atol(argv[i + 1]);
1183			i++;
1184			break;
1185		case 'm':
1186			if (argc < i + 2) {
1187				show_usage(argc, argv);
1188				goto error;
1189			}
1190			opt_modulo = atol(argv[i + 1]);
1191			if (opt_modulo < 0) {
1192				show_usage(argc, argv);
1193				goto error;
1194			}
1195			i++;
1196			break;
1197		case 's':
1198			if (argc < i + 2) {
1199				show_usage(argc, argv);
1200				goto error;
1201			}
1202			opt_sleep = atol(argv[i + 1]);
1203			if (opt_sleep < 0) {
1204				show_usage(argc, argv);
1205				goto error;
1206			}
1207			i++;
1208			break;
1209		case 'y':
1210			opt_yield = 1;
1211			break;
1212		case 'k':
1213			opt_signal = 1;
1214			break;
1215		case 'd':
1216			opt_disable_rseq = 1;
1217			break;
1218		case 'D':
1219			if (argc < i + 2) {
1220				show_usage(argc, argv);
1221				goto error;
1222			}
1223			opt_disable_mod = atol(argv[i + 1]);
1224			if (opt_disable_mod < 0) {
1225				show_usage(argc, argv);
1226				goto error;
1227			}
1228			i++;
1229			break;
1230		case 't':
1231			if (argc < i + 2) {
1232				show_usage(argc, argv);
1233				goto error;
1234			}
1235			opt_threads = atol(argv[i + 1]);
1236			if (opt_threads < 0) {
1237				show_usage(argc, argv);
1238				goto error;
1239			}
1240			i++;
1241			break;
1242		case 'r':
1243			if (argc < i + 2) {
1244				show_usage(argc, argv);
1245				goto error;
1246			}
1247			opt_reps = atoll(argv[i + 1]);
1248			if (opt_reps < 0) {
1249				show_usage(argc, argv);
1250				goto error;
1251			}
1252			i++;
1253			break;
1254		case 'h':
1255			show_usage(argc, argv);
1256			goto end;
1257		case 'T':
1258			if (argc < i + 2) {
1259				show_usage(argc, argv);
1260				goto error;
1261			}
1262			opt_test = *argv[i + 1];
1263			switch (opt_test) {
1264			case 's':
1265			case 'l':
1266			case 'i':
1267			case 'b':
1268			case 'm':
 
1269				break;
1270			default:
1271				show_usage(argc, argv);
1272				goto error;
1273			}
1274			i++;
1275			break;
1276		case 'v':
1277			verbose = 1;
1278			break;
1279		case 'M':
1280			opt_mb = 1;
1281			break;
1282		default:
1283			show_usage(argc, argv);
1284			goto error;
1285		}
1286	}
1287
1288	loop_cnt_1 = loop_cnt[1];
1289	loop_cnt_2 = loop_cnt[2];
1290	loop_cnt_3 = loop_cnt[3];
1291	loop_cnt_4 = loop_cnt[4];
1292	loop_cnt_5 = loop_cnt[5];
1293	loop_cnt_6 = loop_cnt[6];
1294
1295	if (set_signal_handler())
1296		goto error;
1297
1298	if (!opt_disable_rseq && rseq_register_current_thread())
1299		goto error;
 
 
 
 
1300	switch (opt_test) {
1301	case 's':
1302		printf_verbose("spinlock\n");
1303		test_percpu_spinlock();
1304		break;
1305	case 'l':
1306		printf_verbose("linked list\n");
1307		test_percpu_list();
1308		break;
1309	case 'b':
1310		printf_verbose("buffer\n");
1311		test_percpu_buffer();
1312		break;
1313	case 'm':
1314		printf_verbose("memcpy buffer\n");
1315		test_percpu_memcpy_buffer();
1316		break;
1317	case 'i':
1318		printf_verbose("counter increment\n");
1319		test_percpu_inc();
 
 
 
 
1320		break;
1321	}
1322	if (!opt_disable_rseq && rseq_unregister_current_thread())
1323		abort();
1324end:
1325	return 0;
1326
1327error:
1328	return -1;
1329}