1 // SPDX-License-Identifier: GPL-2.0 2 #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 8192 12 13 static 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, (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 stack_size = stack_size > STACK_SIZE ? STACK_SIZE : stack_size; 38 39 memcpy(buf, (void *) sp, stack_size); 40 #ifdef MEMORY_SANITIZER 41 /* 42 * Copying the stack may copy msan poison, avoid false positives in the 43 * unwinder by removing the poison here. 44 */ 45 __msan_unpoison(buf, stack_size); 46 #endif 47 stack->data = (char *) buf; 48 stack->size = stack_size; 49 return 0; 50 } 51 52 int test__arch_unwind_sample(struct perf_sample *sample, 53 struct thread *thread) 54 { 55 struct regs_dump *regs = &sample->user_regs; 56 u64 *buf; 57 58 buf = malloc(sizeof(u64) * PERF_REGS_MAX); 59 if (!buf) { 60 pr_debug("failed to allocate sample uregs data\n"); 61 return -1; 62 } 63 64 #ifdef MEMORY_SANITIZER 65 /* 66 * Assignments to buf in the assembly function perf_regs_load aren't 67 * seen by memory sanitizer. Zero the memory to convince memory 68 * sanitizer the memory is initialized. 69 */ 70 memset(buf, 0, sizeof(u64) * PERF_REGS_MAX); 71 #endif 72 perf_regs_load(buf); 73 regs->abi = PERF_SAMPLE_REGS_ABI; 74 regs->regs = buf; 75 regs->mask = PERF_REGS_MASK; 76 77 return sample_ustack(sample, thread, buf); 78 } 79