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 "record.h" 6 #include "unwind.h" 7 #include <string.h> 8 9 #define perf_event_arm_regs perf_event_arm64_regs 10 #include "../../arch/arm64/include/uapi/asm/perf_regs.h" 11 #undef perf_event_arm_regs 12 13 struct entries { 14 u64 stack[2]; 15 size_t length; 16 }; 17 18 #define SMPL_REG_MASK(b) (1ULL << (b)) 19 20 void add_leaf_frame_caller_opts_aarch64(struct record_opts *opts) 21 { 22 opts->sample_user_regs |= SMPL_REG_MASK(PERF_REG_ARM64_LR); 23 } 24 25 static bool get_leaf_frame_caller_enabled(struct perf_sample *sample) 26 { 27 struct regs_dump *regs; 28 29 if (callchain_param.record_mode != CALLCHAIN_FP) 30 return false; 31 32 regs = perf_sample__user_regs(sample); 33 return regs->regs && regs->mask & SMPL_REG_MASK(PERF_REG_ARM64_LR); 34 } 35 36 static int add_entry(struct unwind_entry *entry, void *arg) 37 { 38 struct entries *entries = arg; 39 40 entries->stack[entries->length++] = entry->ip; 41 return 0; 42 } 43 44 u64 get_leaf_frame_caller_aarch64(struct perf_sample *sample, struct thread *thread, int usr_idx) 45 { 46 int ret; 47 struct entries entries = {}; 48 struct regs_dump old_regs, *regs; 49 50 if (!get_leaf_frame_caller_enabled(sample)) 51 return 0; 52 53 /* 54 * If PC and SP are not recorded, get the value of PC from the stack 55 * and set its mask. SP is not used when doing the unwinding but it 56 * still needs to be set to prevent failures. 57 */ 58 regs = perf_sample__user_regs(sample); 59 memcpy(&old_regs, regs, sizeof(*regs)); 60 if (!(regs->mask & SMPL_REG_MASK(PERF_REG_ARM64_PC))) { 61 regs->cache_mask |= SMPL_REG_MASK(PERF_REG_ARM64_PC); 62 regs->cache_regs[PERF_REG_ARM64_PC] = sample->callchain->ips[usr_idx+1]; 63 } 64 65 if (!(regs->mask & SMPL_REG_MASK(PERF_REG_ARM64_SP))) { 66 regs->cache_mask |= SMPL_REG_MASK(PERF_REG_ARM64_SP); 67 regs->cache_regs[PERF_REG_ARM64_SP] = 0; 68 } 69 70 ret = unwind__get_entries(add_entry, &entries, thread, sample, 2, true); 71 memcpy(regs, &old_regs, sizeof(*regs)); 72 73 if (ret || entries.length != 2) 74 return ret; 75 76 return callchain_param.order == ORDER_CALLER ? entries.stack[0] : entries.stack[1]; 77 } 78