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(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_SANITIZER 42 /* 43 * Copying the stack may copy msan poison, avoid false positives in the 44 * unwinder by removing the poison here. 45 */ 46 __msan_unpoison(buf, stack_size); 47 #endif 48 stack->data = (char *) buf; 49 stack->size = stack_size; 50 return 0; 51 } 52 53 int 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_SANITIZER 66 /* 67 * Assignments to buf in the assembly function perf_regs_load aren't 68 * seen by memory sanitizer. Zero the memory to convince memory 69 * sanitizer the memory is initialized. 70 */ 71 memset(buf, 0, sizeof(u64) * PERF_REGS_MAX); 72 #endif 73 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