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Commit f58faed7 authored by Athira Rajeev's avatar Athira Rajeev Committed by Arnaldo Carvalho de Melo
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perf bench: Fix numa bench to fix usage of affinity for machines with #CPUs > 1K

The 'perf bench numa' testcase fails on systems with more than 1K CPUs.

Testcase: perf bench numa mem -p 1 -t 3 -P 512 -s 100 -zZ0qcm --thp  1

Snippet of code:

  <<>>
  perf: bench/numa.c:302: bind_to_node: Assertion `!(ret)' failed.
  Aborted (core dumped)
  <<>>

bind_to_node() uses "sched_getaffinity" to save the original cpumask and
this call is returning EINVAL ((invalid argument).

This happens because the default mask size in glibc is 1024.  To
overcome this 1024 CPUs mask size limitation of cpu_set_t, change the
mask size using the CPU_*_S macros ie, use CPU_ALLOC to allocate
cpumask, CPU_ALLOC_SIZE for size.

Apart from fixing this for "orig_mask", apply same logic to "mask" as
well which is used to setaffinity so that mask size is large enough to
represent number of possible CPU's in the system.

sched_getaffinity is used in one more place in perf numa bench. It is in
"bind_to_cpu" function. Apply the same logic ...
parent 8cb7a188
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