LoongArch: Fix callchain parse error with kernel tracepoint events
commit d3119bc9 upstream. In order to fix perf's callchain parse error for LoongArch, we implement perf_arch_fetch_caller_regs() which fills several necessary registers used for callchain unwinding, including sp, fp, and era. This is similar to the following commits. commit b3eac026: ("arm: perf: Fix callchain parse error with kernel tracepoint events") commit 5b09a094: ("arm64: perf: Fix callchain parse error with kernel tracepoint events") commit 9a7e8ec0: ("riscv: perf: Fix callchain parse error with kernel tracepoint events") Test with commands: perf record -e sched:sched_switch -g --call-graph dwarf perf report Without this patch: Children Self Command Shared Object Symbol ........ ........ ............. ................. .................... 43.41% 43.41% swapper [unknown] [k] 0000000000000000 10.94% 10.94% loong-container [unknown] [k] 0000000000000000 | |--5.98%--0x12006ba38 | |--2.56%--0x12006bb84 | --2.40%--0x12006b6b8 With this patch, callchain can be parsed correctly: Children Self Command Shared Object Symbol ........ ........ ............. ................. .................... 47.57% 47.57% swapper [kernel.vmlinux] [k] __schedule | ---__schedule 26.76% 26.76% loong-container [kernel.vmlinux] [k] __schedule | |--13.78%--0x12006ba38 | | | |--9.19%--__schedule | | | --4.59%--handle_syscall | do_syscall | sys_futex | do_futex | futex_wait | futex_wait_queue_me | hrtimer_start_range_ns | __schedule | |--8.38%--0x12006bb84 | handle_syscall | do_syscall | sys_epoll_pwait | do_epoll_wait | schedule_hrtimeout_range_clock | hrtimer_start_range_ns | __schedule | --4.59%--0x12006b6b8 handle_syscall do_syscall sys_nanosleep hrtimer_nanosleep do_nanosleep hrtimer_start_range_ns __schedule Cc: stable@vger.kernel.org Fixes: b37042b2 ("LoongArch: Add perf events support") Reported-by:Youling Tang <tangyouling@kylinos.cn> Suggested-by:
Youling Tang <tangyouling@kylinos.cn> Signed-off-by:
Huacai Chen <chenhuacai@loongson.cn> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
parent
8292f4f8
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