Re: [PATCH bpf-next v2 7/9] samples/bpf: add a test for bpf_get_stack helper

[Yonghong Song <yhs@fb.com>]

On 4/18/18 9:37 PM, Alexei Starovoitov wrote:
> On Wed, Apr 18, 2018 at 09:54:42AM -0700, Yonghong Song wrote:
>> The test attached a kprobe program to kernel function sys_write.
>> It tested to get stack for user space, kernel space and user
>> space with build_id request. It also tested to get user
>> and kernel stack into the same buffer with back-to-back
>> bpf_get_stack helper calls.
>>
>> Whenever the kernel stack is available, the user space
>> application will check to ensure that sys_write/SyS_write
>> is part of the stack.
>>
>> Signed-off-by: Yonghong Song <yhs@fb.com>
>> ---
>>   samples/bpf/Makefile               |   4 +
>>   samples/bpf/trace_get_stack_kern.c |  86 +++++++++++++++++++++
>>   samples/bpf/trace_get_stack_user.c | 150 +++++++++++++++++++++++++++++++++++++
>>   3 files changed, 240 insertions(+)
> 
> since perf_read is being refactored out of trace_output_user.c in the previous patch
> please move it to selftests (instead of bpf_load.c) and move
> this whole test to selftests as well.

I put it here since I am attaching to a kprobe so that I can compare 
address. I guess I can still do it by attaching to a kernel tracepoint.
Will move the tests to selftests as suggested.