Thread (7 messages) flat view 7 messages, 4 authors, 2020-08-05

Re: [PATCH] selftests/net: skip msg_zerocopy test if we have less than 4 CPUs

From: Eric Dumazet <hidden>
Date: 2020-08-05 00:54:24
Also in: kernel-janitors, linux-kselftest, lkml


On 8/4/20 5:30 AM, Colin King wrote:
quoted hunk ↗ jump to hunk
From: Colin Ian King <redacted>

The current test will exit with a failure if it cannot set affinity on
specific CPUs which is problematic when running this on single CPU
systems. Add a check for the number of CPUs and skip the test if
the CPU requirement is not met.

Signed-off-by: Colin Ian King <redacted>
---
 tools/testing/selftests/net/msg_zerocopy.sh | 5 +++++
 1 file changed, 5 insertions(+)
diff --git a/tools/testing/selftests/net/msg_zerocopy.sh b/tools/testing/selftests/net/msg_zerocopy.sh
index 825ffec85cea..97bc527e1297 100755
--- a/tools/testing/selftests/net/msg_zerocopy.sh
+++ b/tools/testing/selftests/net/msg_zerocopy.sh
@@ -21,6 +21,11 @@ readonly DADDR6='fd::2'
 
 readonly path_sysctl_mem="net.core.optmem_max"
 
+if [[ $(nproc) -lt 4 ]]; then
+	echo "SKIP: test requires at least 4 CPUs"
+	exit 4
+fi
+
 # No arguments: automated test
 if [[ "$#" -eq "0" ]]; then
 	$0 4 tcp -t 1
Test explicitly uses CPU 2 and 3, right ?

nproc could be 500, yet cpu 2 or 3 could be offline

# cat /sys/devices/system/cpu/cpu3/online
0
# echo $(nproc)
71
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