[PATCH] perf bench numa: Fix cpu0 binding

[Jiri Olsa <jolsa@kernel.org>]

Michael reported an issue with perf bench numa failing with
binding to cpu0 with '-0' option.

  # perf bench numa mem -p 3 -t 1 -P 512 -s 100 -zZcm0 --thp 1 -M 1 -ddd
  # Running 'numa/mem' benchmark:

   # Running main, "perf bench numa numa-mem -p 3 -t 1 -P 512 -s 100 -zZcm0 --thp 1 -M 1 -ddd"
  binding to node 0, mask: 0000000000000001 => -1
  perf: bench/numa.c:356: bind_to_memnode: Assertion `!(ret)' failed.
  Aborted (core dumped)

This happens when the cpu0 is not part of node0,
which is the benchmark assumption and we can see
that's not the case for some powerpc servers.

Using correct node for cpu0 binding.

Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Reported-by: Michael Petlan <mpetlan@redhat.com>
Link: http://lkml.kernel.org/n/tip-9m9j1xm3xjaa1sogvbva0o8i@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/bench/numa.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/perf/bench/numa.c b/tools/perf/bench/numa.c
index a640ca7aaada..513cb2f2fa32 100644
--- a/tools/perf/bench/numa.c
+++ b/tools/perf/bench/numa.c
@@ -379,8 +379,10 @@ static u8 *alloc_data(ssize_t bytes0, int map_flags,
 
 	/* Allocate and initialize all memory on CPU#0: */
 	if (init_cpu0) {
-		orig_mask = bind_to_node(0);
-		bind_to_memnode(0);
+		int node = numa_node_of_cpu(0);
+
+		orig_mask = bind_to_node(node);
+		bind_to_memnode(node);
 	}
 
 	bytes = bytes0 + HPSIZE;
-- 
2.21.0