From: Bobby Eshleman <bobbyeshleman@meta.com>

These functions are reused by the VM tests to collect and compare dmesg
warnings and oops counts. The future VM-specific tests use them heavily.
This patches relies on vm_ssh() already supporting namespaces.

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
---
Changes in v11:
- break these out into an earlier patch so that they can be used
  directly in new patches (instead of causing churn by adding this
  later)
---
 tools/testing/selftests/vsock/vmtest.sh | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
index c4d73dd0a4cf..4b5929ffc9eb 100755
--- a/tools/testing/selftests/vsock/vmtest.sh
+++ b/tools/testing/selftests/vsock/vmtest.sh
@@ -380,6 +380,17 @@ host_wait_for_listener() {
 	fi
 }
 
+vm_dmesg_oops_count() {
+	local ns=$1
+
+	vm_ssh "${ns}" -- dmesg 2>/dev/null | grep -c -i 'Oops'
+}
+
+vm_dmesg_warn_count() {
+	local ns=$1
+
+	vm_ssh "${ns}" -- dmesg --level=warn 2>/dev/null | grep -c -i 'vsock'
+}
 
 vm_vsock_test() {
 	local ns=$1
@@ -587,8 +598,8 @@ run_shared_vm_test() {
 
 	host_oops_cnt_before=$(dmesg | grep -c -i 'Oops')
 	host_warn_cnt_before=$(dmesg --level=warn | grep -c -i 'vsock')
-	vm_oops_cnt_before=$(vm_ssh "init_ns" -- dmesg | grep -c -i 'Oops')
-	vm_warn_cnt_before=$(vm_ssh "init_ns" -- dmesg --level=warn | grep -c -i 'vsock')
+	vm_oops_cnt_before=$(vm_dmesg_oops_count "init_ns")
+	vm_warn_cnt_before=$(vm_dmesg_warn_count "init_ns")
 
 	name=$(echo "${1}" | awk '{ print $1 }')
 	eval test_"${name}"
@@ -606,13 +617,13 @@ run_shared_vm_test() {
 		rc=$KSFT_FAIL
 	fi
 
-	vm_oops_cnt_after=$(vm_ssh "init_ns" -- dmesg | grep -i 'Oops' | wc -l)
+	vm_oops_cnt_after=$(vm_dmesg_oops_count "init_ns")
 	if [[ ${vm_oops_cnt_after} -gt ${vm_oops_cnt_before} ]]; then
 		echo "FAIL: kernel oops detected on vm" | log_host
 		rc=$KSFT_FAIL
 	fi
 
-	vm_warn_cnt_after=$(vm_ssh "init_ns" -- dmesg --level=warn | grep -c -i 'vsock')
+	vm_warn_cnt_after=$(vm_dmesg_warn_count "init_ns")
 	if [[ ${vm_warn_cnt_after} -gt ${vm_warn_cnt_before} ]]; then
 		echo "FAIL: kernel warning detected on vm" | log_host
 		rc=$KSFT_FAIL

-- 
2.47.3