Re: Strange pthread_self() return value

[RVP <rvp%SDF.ORG@localhost>]

On Fri, 11 Jun 2021, nia wrote:

> The segfault is actually in hwloc, a library used by OpenCL:
>
> Program received signal SIGSEGV, Segmentation fault.
> 0x0000764e5660a2c8 in pthread_getaffinity_np () from /usr/lib/libpthread.so.1
> (gdb) bt
> #0  0x0000764e5660a2c8 in pthread_getaffinity_np () from /usr/lib/libpthread.so.1
> #1  0x0000764e5ec1f86e in hwloc_netbsd_get_thread_cpubind (topology=topology@entry=0x764e60060000,
>    tid=0xffffffffffffffff, hwloc_cpuset=hwloc_cpuset@entry=0x764e60078a80, flags=flags@entry=4)
>    at topology-netbsd.c:112
> #2  0x0000764e5ec1f8d3 in hwloc_netbsd_get_thisthread_cpubind (topology=0x764e60060000,
>    hwloc_cpuset=0x764e60078a80, flags=4) at topology-netbsd.c:133
>
> Notice how "tid" is 0xffffffffffffffff. Attempting to set the affinity
> of thread "0xffffffffffffffff" obviously fails.
>
> However, this value comes from the return value of pthread_self():
>
> static int
> hwloc_netbsd_get_thisthread_cpubind(hwloc_topology_t topology, hwloc_bitmap_t hwloc_cpuset, int flags)
> {
>  return hwloc_netbsd_get_thread_cpubind(topology, pthread_self(), hwloc_cpuset, flags);
> }
>
> What's going on?

1. Is `hwloc_thread_t' the same as `pthread_t' when hwloc is compiled
   on NetBSD?

2. Does a `make check' of hwloc on NetBSD pass?

-RVP