[PATCH 4.9 14/83] perf bench numa: Fix cpu0 binding

From: Greg Kroah-Hartman
Date: Wed Sep 04 2019 - 13:59:22 EST


[ Upstream commit 6bbfe4e602691b90ac866712bd4c43c51e546a60 ]

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.

Reported-by: Michael Petlan <mpetlan@xxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Satheesh Rajendran <sathnaga@xxxxxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20190801142642.28004-1-jolsa@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 e58be7eeced83..7b364f2926d4f 100644
--- a/tools/perf/bench/numa.c
+++ b/tools/perf/bench/numa.c
@@ -373,8 +373,10 @@ 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;
--
2.20.1