[PATCH AUTOSEL 4.14 20/44] perf bench numa: Fix cpu0 binding

From: Sasha Levin
Date: Tue Aug 13 2019 - 22:21:35 EST


From: Jiri Olsa <jolsa@xxxxxxxxxx>

[ 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 997875c770b10..275f1c3c73b62 100644
--- a/tools/perf/bench/numa.c
+++ b/tools/perf/bench/numa.c
@@ -378,8 +378,10 @@ 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