sysdetect: all tests hang on Intel Raptorlake

[willowec]

Tests for the sysdetect component in src/components/sysdetect/tests hang on an 13th Gen Intel(R) Core(TM) i7-13700 (raptorlake) due to sysdetect not being designed to handle heterogeneous CPU cores. The hang occurs somewhere in fill_cpu_info() of src/components/sysdetect/cpu.c. It seems likely that adding support for heterogeneous processors to the sysdetect component will be a fairly intensive process.

To reproduce:
On a machine with an Intel Raptorlake processor, configure & compile PAPI and then run src/components/sysdetect/tests/query_device_simple

Example output with PAPI_DEBUG=ALL:

$ ./components/sysdetect/tests/query_device_simple
...
Testing sysdetect component with PAPI 7.2.0

Device Summary -----------------------------------------------------------------
Vendor           DevCount 
SUBSTRATE:components/sysdetect/cpu.c:fill_cpu_info:54:235706 error: function cpu_get_attribute_at(CPU_ATTR__CACHE_INST_PRESENT, level, &a) failed with error -1
SUBSTRATE:components/sysdetect/cpu.c:fill_cpu_info:55:235706 error: function cpu_get_attribute_at(CPU_ATTR__CACHE_DATA_PRESENT, level, &b) failed with error -1
SUBSTRATE:components/sysdetect/cpu.c:fill_cpu_info:56:235706 error: function cpu_get_attribute_at(CPU_ATTR__CACHE_UNIF_PRESENT, level, &c) failed with error -1

[Treece-Burgess]

@willowec Are you trying to use the sysdetect component on the Raptorlake CPU or is this causing you an issue during the build process for PAPI since the sysdetect component is enabled by default?

If the latter, PR #265 will allow you to disable the sysdetect component.

[willowec]

@Treece-Burgess This is just an issue I noticed during the development of PR #238 while running make fulltest to make sure my code wasn't breaking anything. I plan to work on a fix so that sysdetect can handle heterogeneous CPU's, but I haven't fully scoped out how large of a change that is yet. I would have assigned this ticket to myself but I don't have the permissions to. Regardless, I figured it would be good to document the bug in an issue anyway.

[willowec]

Now that I am more familiar with the sysdetect component and how it relates to PAPI as a whole, it seems like truly supporting heterogeneous processors would be a massive undertaking and require rewriting most of the component. For now I am just adding a patch to at least prevent the infinite loop.

[willowec]

This is fixed by #269