> On May 22, 2019, at 6:58 AM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> On Tue, May 21, 2019 at 01:48:13PM -0700, Song Liu wrote:
>> Commit d15d356887e7 removes regs->ip for !perf_hw_regs(regs) case. This
>> breaks tests like test_stacktrace_map from selftests/bpf/tests_prog.
>
> That test is broken by something else; just the one entry is wrong too.
>
> That said, yes the patch below is actually correct, but the above
> description is misleading at best.
How about we change it to:
Commit d15d356887e7 removes regs->ip for !perf_hw_regs(regs) case. This
patch adds regs->ip back.
Shall I send v2 with the change?
Thanks,
Song
>
>> This patch adds regs->ip back.
>>
>> Fixes: d15d356887e7 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER")
>> Cc: Kairui Song <kasong@xxxxxxxxxx>
>> Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
>> Signed-off-by: Song Liu <songliubraving@xxxxxx>
>> ---
>> arch/x86/events/core.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
>> index f315425d8468..7b8a9eb4d5fd 100644
>> --- a/arch/x86/events/core.c
>> +++ b/arch/x86/events/core.c
>> @@ -2402,9 +2402,9 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re
>> return;
>> }
>>
>> + if (perf_callchain_store(entry, regs->ip))
>> + return;
>> if (perf_hw_regs(regs)) {
>> - if (perf_callchain_store(entry, regs->ip))
>> - return;
>> unwind_start(&state, current, regs, NULL);
>> } else {
>> unwind_start(&state, current, NULL, (void *)regs->sp);
>> --
>> 2.17.1
>>
