在MIPS调试内核上无法执行，无法启用frame_pointer

Question

我正在尝试将perf工具用于MIPS并在获得回栈方面遇到一些麻烦。

如何为mips启用FRAME_POINTER？我已启用DEBUG_KERNEL，但看起来-fno-omit-frame-pointer不适用于kernel中的MIPS拱。

这是否意味着对于MIPS无法使用perf实现基于帧指针的堆栈展开？

我看不到mips工具链抱怨-fno-omit-frame-pointer标志

EDIT1

我能够记录性能事件。性能报告的样本输出

如果不取消堆栈，报表将无济于事。

# ./perf --version
perf version 5.6.rc2.gd04712cd3bd7
# uname -a
Linux localhost 3.14.28-1.19 #1 SMP Mon Feb 17 16:48:44 IST 2020 mips GNU/Linux

EDIT2

检测到性能特征

Auto-detecting system features:
...                         dwarf: [ on  ]
...            dwarf_getlocations: [ on  ]
...                         glibc: [ on  ]
...                          gtk2: [ OFF ]
...                      libaudit: [ on  ]
...                        libbfd: [ OFF ]
...                        libcap: [ OFF ]
...                        libelf: [ on  ]
...                       libnuma: [ OFF ]
...        numa_num_possible_cpus: [ OFF ]
...                       libperl: [ OFF ]
...                     libpython: [ OFF ]
...                     libcrypto: [ OFF ]
...                     libunwind: [ OFF ]
...            libdw-dwarf-unwind: [ on  ]
...                          zlib: [ on  ]
...                          lzma: [ on  ]
...                     get_cpuid: [ OFF ]
...                           bpf: [ OFF ]
...                        libaio: [ on  ]
...                       libzstd: [ OFF ]
...        disassembler-four-args: [ OFF ]

EDIT3

我看到libunwind的功能测试失败

cat linux-5.6-rc2/tools/build/feature/test-libunwind.make.output
/tmp/ccQnV5jZ.o: In function `main':
test-libunwind.c:(.text+0x1c): undefined reference to `_Umips_create_addr_space'
test-libunwind.c:(.text+0x4c): undefined reference to `_Umips_init_remote'
test-libunwind.c:(.text+0x70): undefined reference to `_Umips_dwarf_search_unwind_table'
collect2: error: ld returned 1 exit status

如果我看到makefile用于功能测试，则libunwind链接未针对MIPS完成。

EDIT4

常用工作流程

perf record -F 99 -ag -e cycles:u -- sleep 5
perf report

尝试使用矮人

# perf record -F 99 -ag --call-graph=dwarf -- sleep 10                                                                                                                                                   
Error:
The sys_perf_event_open() syscall returned with 89 (Function not implemented) for event (cycles).
/bin/dmesg | grep -i perf may provide additional information.

dmesg为空