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brintos / linux-shallow public Read only

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1// SPDX-License-Identifier: GPL-2.02#include "arm64-frame-pointer-unwind-support.h"3#include "callchain.h"4#include "event.h"5#include "perf_regs.h" // SMPL_REG_MASK6#include "unwind.h"7 8#define perf_event_arm_regs perf_event_arm64_regs9#include "../../arch/arm64/include/uapi/asm/perf_regs.h"10#undef perf_event_arm_regs11 12struct entries {13	u64 stack[2];14	size_t length;15};16 17static bool get_leaf_frame_caller_enabled(struct perf_sample *sample)18{19	return callchain_param.record_mode == CALLCHAIN_FP && sample->user_regs.regs20		&& sample->user_regs.mask & SMPL_REG_MASK(PERF_REG_ARM64_LR);21}22 23static 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 31u64 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 stack42	 * and set its mask. SP is not used when doing the unwinding but it43	 * 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