From d13fb04a4bf0811b593843f7d2385fac5cf313c8 Mon Sep 17 00:00:00 2001
From: Bobby Eshleman <bobbyeshleman@meta.com>
Date: Sat, 8 Nov 2025 08:00:59 -0800
Subject: [PATCH] selftests/vsock: identify and execute tests that can re-use
 VM

In preparation for future patches that introduce tests that cannot
re-use the same VM, add functions to identify those that *can* re-use a
VM.

By continuing to re-use the same VM for these tests we can save time by
avoiding the delay of booting a VM for every test.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20251108-vsock-selftests-fixes-and-improvements-v4-8-d5e8d6c87289@meta.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/testing/selftests/vsock/vmtest.sh | 63 ++++++++++++++++++++-----
 1 file changed, 50 insertions(+), 13 deletions(-)

diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
index 2dd9bbb8c4a9d..a1c2969c44b6c 100755
--- a/tools/testing/selftests/vsock/vmtest.sh
+++ b/tools/testing/selftests/vsock/vmtest.sh
@@ -46,6 +46,8 @@ readonly TEST_DESCS=(
 	"Run vsock_test using the loopback transport in the VM."
 )
 
+readonly USE_SHARED_VM=(vm_server_host_client vm_client_host_server vm_loopback)
+
 VERBOSE=0
 
 usage() {
@@ -461,7 +463,44 @@ test_vm_loopback() {
 	return "${KSFT_PASS}"
 }
 
-run_test() {
+shared_vm_test() {
+	local tname
+
+	tname="${1}"
+
+	for testname in "${USE_SHARED_VM[@]}"; do
+		if [[ "${tname}" == "${testname}" ]]; then
+			return 0
+		fi
+	done
+
+	return 1
+}
+
+shared_vm_tests_requested() {
+	for arg in "$@"; do
+		if shared_vm_test "${arg}"; then
+			return 0
+		fi
+	done
+
+	return 1
+}
+
+run_shared_vm_tests() {
+	local arg
+
+	for arg in "$@"; do
+		if ! shared_vm_test "${arg}"; then
+			continue
+		fi
+
+		run_shared_vm_test "${arg}"
+		check_result "$?" "${arg}"
+	done
+}
+
+run_shared_vm_test() {
 	local host_oops_cnt_before
 	local host_warn_cnt_before
 	local vm_oops_cnt_before
@@ -537,23 +576,21 @@ handle_build
 
 echo "1..${#ARGS[@]}"
 
-log_host "Booting up VM"
-pidfile="$(create_pidfile)"
-vm_start "${pidfile}"
-vm_wait_for_ssh
-log_host "VM booted up"
-
 cnt_pass=0
 cnt_fail=0
 cnt_skip=0
 cnt_total=0
-for arg in "${ARGS[@]}"; do
-	run_test "${arg}"
-	rc=$?
-	check_result "${rc}" "${arg}"
-done
 
-terminate_pidfiles "${pidfile}"
+if shared_vm_tests_requested "${ARGS[@]}"; then
+	log_host "Booting up VM"
+	pidfile="$(create_pidfile)"
+	vm_start "${pidfile}"
+	vm_wait_for_ssh
+	log_host "VM booted up"
+
+	run_shared_vm_tests "${ARGS[@]}"
+	terminate_pidfiles "${pidfile}"
+fi
 
 echo "SUMMARY: PASS=${cnt_pass} SKIP=${cnt_skip} FAIL=${cnt_fail}"
 echo "Log: ${LOG}"
-- 
2.47.3