1 // SPDX-License-Identifier: GPL-2.0 2 #include "arm64-frame-pointer-unwind-support.h" 3 #include "callchain.h" 4 #include "event.h" 5 #include "perf_regs.h" // SMPL_REG_MASK 6 #include "unwind.h" 7 8 #define perf_event_arm_regs perf_event_arm64_regs 9 #include "../../arch/arm64/include/uapi/asm/perf_regs.h" 10 #undef perf_event_arm_regs 11 12 struct entries { 13 u64 stack[2]; 14 size_t length; 15 }; 16 17 static bool get_leaf_frame_caller_enabled(struct perf_sample *sample) 18 { 19 return callchain_param.record_mode == CALLCHAIN_FP && sample->user_regs.regs 20 && sample->user_regs.mask & SMPL_REG_MASK(PERF_REG_ARM64_LR); 21 } 22 23 static int add_entry(struct unwind_entry *entry, void *arg) 24 { 25 struct entries *entries = arg; 26 27 entries->stack[entries->length++] = entry->ip; 28 return 0; 29 } 30 31 u64 get_leaf_frame_caller_aarch64(struct perf_sample *sample, struct thread *thread, int usr_idx) 32 { 33 int ret; 34 struct entries entries = {}; 35 struct regs_dump old_regs = sample->user_regs; 36 37 if (!get_leaf_frame_caller_enabled(sample)) 38 return 0; 39 40 /* 41 * If PC and SP are not recorded, get the value of PC from the stack 42 * and set its mask. SP is not used when doing the unwinding but it 43 * still needs to be set to prevent failures. 44 */ 45 46 if (!(sample->user_regs.mask & SMPL_REG_MASK(PERF_REG_ARM64_PC))) { 47 sample->user_regs.cache_mask |= SMPL_REG_MASK(PERF_REG_ARM64_PC); 48 sample->user_regs.cache_regs[PERF_REG_ARM64_PC] = sample->callchain->ips[usr_idx+1]; 49 } 50 51 if (!(sample->user_regs.mask & SMPL_REG_MASK(PERF_REG_ARM64_SP))) { 52 sample->user_regs.cache_mask |= SMPL_REG_MASK(PERF_REG_ARM64_SP); 53 sample->user_regs.cache_regs[PERF_REG_ARM64_SP] = 0; 54 } 55 56 ret = unwind__get_entries(add_entry, &entries, thread, sample, 2, true); 57 sample->user_regs = old_regs; 58 59 if (ret || entries.length != 2) 60 return ret; 61 62 return callchain_param.order == ORDER_CALLER ? entries.stack[0] : entries.stack[1]; 63 } 64