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1// SPDX-License-Identifier: GPL-2.02#include <string.h>3#include "perf_regs.h"4#include "thread.h"5#include "map.h"6#include "maps.h"7#include "event.h"8#include "debug.h"9#include "tests/tests.h"10 11#define STACK_SIZE 819212 13static int sample_ustack(struct perf_sample *sample,14			 struct thread *thread, u64 *regs)15{16	struct stack_dump *stack = &sample->user_stack;17	struct map *map;18	unsigned long sp;19	u64 stack_size, *buf;20 21	buf = malloc(STACK_SIZE);22	if (!buf) {23		pr_debug("failed to allocate sample uregs data\n");24		return -1;25	}26 27	sp = (unsigned long) regs[PERF_REG_X86_SP];28 29	map = maps__find(thread__maps(thread), (u64)sp);30	if (!map) {31		pr_debug("failed to get stack map\n");32		free(buf);33		return -1;34	}35 36	stack_size = map__end(map) - sp;37	map__put(map);38	stack_size = stack_size > STACK_SIZE ? STACK_SIZE : stack_size;39 40	memcpy(buf, (void *) sp, stack_size);41#ifdef MEMORY_SANITIZER42	/*43	 * Copying the stack may copy msan poison, avoid false positives in the44	 * unwinder by removing the poison here.45	 */46	__msan_unpoison(buf, stack_size);47#endif48	stack->data = (char *) buf;49	stack->size = stack_size;50	return 0;51}52 53int test__arch_unwind_sample(struct perf_sample *sample,54			     struct thread *thread)55{56	struct regs_dump *regs = &sample->user_regs;57	u64 *buf;58 59	buf = malloc(sizeof(u64) * PERF_REGS_MAX);60	if (!buf) {61		pr_debug("failed to allocate sample uregs data\n");62		return -1;63	}64 65#ifdef MEMORY_SANITIZER66	/*67	 * Assignments to buf in the assembly function perf_regs_load aren't68	 * seen by memory sanitizer. Zero the memory to convince memory69	 * sanitizer the memory is initialized.70	 */71	memset(buf, 0, sizeof(u64) * PERF_REGS_MAX);72#endif73	perf_regs_load(buf);74	regs->abi  = PERF_SAMPLE_REGS_ABI;75	regs->regs = buf;76	regs->mask = PERF_REGS_MASK;77 78	return sample_ustack(sample, thread, buf);79}80