perf bench: Fix numa testcase to check if CPU used to bind task is online

perf bench: Fix numa testcase to check if CPU used to bind task is online

Perf numa bench test fails with error:

Testcase:

  ./perf bench numa mem -p 2 -t 1 -P 1024 -C 0,8 -M 1,0 -s 20 -zZq --thp  1 --no-data_rand_walk

Failure snippet:

<<>>
  Running 'numa/mem' benchmark:

  # Running main, "perf bench numa numa-mem -p 2 -t 1 -P 1024 -C 0,8 -M 1,0 -s 20 -zZq --thp 1 --no-data_rand_walk"

  perf: bench/numa.c:333: bind_to_cpumask: Assertion `!(ret)' failed.
<<>>

The Testcases uses CPU's 0 and 8. In function "parse_setup_cpu_list",
There is check to see if cpu number is greater than max cpu's possible
in the system ie via "if (bind_cpu_0 >= g->p.nr_cpus || bind_cpu_1 >=
g->p.nr_cpus) {".

But it could happen that system has say 48 CPU's, but only number of
online CPU's is 0-7. Other CPU's are offlined. Since "g->p.nr_cpus" is
48, so function will go ahead and set bit for CPU 8 also in cpumask (
td->bind_cpumask).

bind_to_cpumask function is called to set affinity using
sched_setaffinity and the cpumask. Since the CPU8 is not present, set
affinity will fail here with EINVAL.

Fix this issue by adding a check to make sure that, CPU's provided in
the input argument values are online before proceeding further and skip
the test. For this, include new helper function "is_cpu_online" in
"tools/perf/util/header.c".

Since "BIT(x)" definition will get included from header.h, remove
that from bench/numa.c

Reported-by: Disha Goel <[email protected]>
Signed-off-by: Athira Jajeev <[email protected]>
Tested-by: Disha Goel <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Madhavan Srinivasan <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Nageswara R Sastry <[email protected]>
Cc: Srikar Dronamraju <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>