Re: [RFC PATCH v1] perf tests: Test annotate with data type profiling and rust

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Sun, Feb 01, 2026 at 11:33:54AM +0100, Dmitry Dolgov wrote:
> > On Fri, Jan 30, 2026 at 09:44:47AM +0100, Dmitry Dolgov wrote:
> > > I'm not managing to reproduce your results, can you please elaborate
> > > some more?
> > 
> > That's most unexpected for me, the test output I see looks like this:
> > 
> >          : 54     for _ in 1..count {
> >     0.00 :   5423b8: mov    %ecx,0x7c(%rsp)
> >     0.00 :   5423bc: mov    %eax,0x80(%rsp)
> >     0.00 :   5423c3: lea    0x7c(%rsp),%rdi
> >    12.28 :   5423c8: call   541f00 <core::iter::range::<impl core::iter::traits::iterator::Iterator for core::ops::range::Range<A>>::next>
> >     0.00 :   5423cd: mov    %eax,0x20(%rsp)
> >    10.21 :   5423d1: jmp    5423d3 <test_rs+0xb3>
> >     0.00 :   5423d3: mov    0x20(%rsp),%eax
> >     0.00 :   5423d7: mov    %eax,%eax
> >     0.00 :   5423d9: test   $0x1,%rax
> >     0.29 :   5423df: je     5423f6 <test_rs+0xd6>
> >          : 65     b.data1 += 1;
> >    13.69 :   5423e1: mov    0x48(%rsp),%rax     # data-type: struct Buf +0x18 (data1)
> >     0.00 :   5423e6: add    $0x1,%rax
> >     0.00 :   5423ea: mov    %rax,0x18(%rsp)     # data-type: u64 +0
> >     0.00 :   5423ef: setb   %al
> >    11.17 :   5423f2: jb     54243a <test_rs+0x11a>
> >     0.00 :   5423f4: jmp    542426 <test_rs+0x106>
> >     0.00 :   5423f6: lea    0x30(%rsp),%rdi
> >          : 73     }
> > 
> > Where '# data-type: struct Buf' is as far as I understand a manifestation of
> > data type profiling succeeding. But my environment has slightly different
> > version of rust -- I need to figure out what's going on here, thanks.
> 
> I've being testing this in the same way, but without any rust code --
> just on a simple datasym workload. Surprisingly, it seems that
> 'data-type: buf' marks are disappearing even in this case starting from:
> 
> c31040085914f1188720073baa43d1483693c0a3 (perf dwarf-regs: Clean up x86
> dwarf_regnum code)
 
> I'm not sure yet why this is happening, but don't see anything in the
> commit mentioning that -- since there are no code-with-type tests yet,
> maybe an unexpected side effect?

Ian, can you please take a look at this?

Cheers,

- Arnaldo