[kvm-unit-tests PATCH v4 10/13] scripts: Do not probe for maximum number of VCPUs when using kvmtool

[Alexandru Elisei]

The --probe-maxsmp parameter updates MAX_SMP with the maximum number of
VCPUs that the host supports. Qemu will exit with an error when creating a
virtual machine if the number of VCPUs is exceeded.

kvmtool behaves differently: it will automatically limit the number of
VCPUs to the what KVM supports, which is exactly what --probe-maxsmp wants
to achieve. When doing --probe-maxsmp with kvmtool, print a message
explaining why it's redundant and don't do anything else.

Reviewed-by: Andrew Jones <andrew.jones at linux.dev>
Reviewed-by: Shaoqin Huang <shahuang at redhat.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei at arm.com>
---

Changes v3->v4:

* Use vmmm_probe_maxsmp() instead of indexing vmm_optname in run_tests.sh.

 run_tests.sh         |  3 ++-
 scripts/runtime.bash | 16 ----------------
 scripts/vmm.bash     | 30 ++++++++++++++++++++++++++++++
 3 files changed, 32 insertions(+), 17 deletions(-)

diff --git a/run_tests.sh b/run_tests.sh
index 150a06a91064..4cfc3cd9e4cf 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -10,6 +10,7 @@ if [ ! -f config.mak ]; then
 fi
 source config.mak
 source scripts/common.bash
+source scripts/vmm.bash
 
 function usage()
 {
@@ -90,7 +91,7 @@ while [ $# -gt 0 ]; do
             list_tests="yes"
             ;;
         --probe-maxsmp)
-            probe_maxsmp
+            vmm_probe_maxsmp $RUNTIME_arch_run
             ;;
         --)
             ;;
diff --git a/scripts/runtime.bash b/scripts/runtime.bash
index 5839ca5ca665..766d1d28fb75 100644
--- a/scripts/runtime.bash
+++ b/scripts/runtime.bash
@@ -207,19 +207,3 @@ function run()
 
     return $ret
 }
-
-#
-# Probe for MAX_SMP, in case it's less than the number of host cpus.
-#
-function probe_maxsmp()
-{
-	local smp
-
-	if smp=$($RUNTIME_arch_run _NO_FILE_4Uhere_ -smp $MAX_SMP |& grep 'SMP CPUs'); then
-		smp=${smp##* }
-		smp=${smp/\(}
-		smp=${smp/\)}
-		echo "Restricting MAX_SMP from ($MAX_SMP) to the max supported ($smp)" >&2
-		MAX_SMP=$smp
-	fi
-}
diff --git a/scripts/vmm.bash b/scripts/vmm.bash
index 44954a711cad..724c96f9e665 100644
--- a/scripts/vmm.bash
+++ b/scripts/vmm.bash
@@ -91,6 +91,23 @@ function qemu_parse_premature_failure()
 	return 0
 }
 
+#
+# Probe for MAX_SMP, in case it's less than the number of host cpus.
+#
+function qemu_probe_maxsmp()
+{
+	local runtime_arch_run="$1"
+	local smp
+
+	if smp=$($runtime_arch_run _NO_FILE_4Uhere_ -smp $MAX_SMP |& grep 'SMP CPUs'); then
+		smp=${smp##* }
+		smp=${smp/\(}
+		smp=${smp/\)}
+		echo "Restricting MAX_SMP from ($MAX_SMP) to the max supported ($smp)" >&2
+		MAX_SMP=$smp
+	fi
+}
+
 function kvmtool_fixup_return_code()
 {
 	local ret=$1
@@ -112,6 +129,12 @@ function kvmtool_parse_premature_failure()
 	return 0
 }
 
+function kvmtool_probe_maxsmp()
+{
+	echo "kvmtool automatically limits the number of VCPUs to maximum supported"
+	echo "The 'smp' test parameter won't be modified"
+}
+
 declare -A vmm_optname=(
 	[qemu,args]='-append'
 	[qemu,default_opts]=''
@@ -119,6 +142,7 @@ declare -A vmm_optname=(
 	[qemu,initrd]='-initrd'
 	[qemu,nr_cpus]='-smp'
 	[qemu,parse_premature_failure]=qemu_parse_premature_failure
+	[qemu,probe_maxsmp]=qemu_probe_maxsmp
 
 	[kvmtool,args]='--params'
 	[kvmtool,default_opts]="$KVMTOOL_DEFAULT_OPTS"
@@ -126,6 +150,7 @@ declare -A vmm_optname=(
 	[kvmtool,initrd]='--initrd'
 	[kvmtool,nr_cpus]='--cpus'
 	[kvmtool,parse_premature_failure]=kvmtool_parse_premature_failure
+	[kvmtool,probe_maxsmp]=kvmtool_probe_maxsmp
 )
 
 function vmm_optname_args()
@@ -158,6 +183,11 @@ function vmm_parse_premature_failure()
 	${vmm_optname[$(vmm_get_target),parse_premature_failure]} "$@"
 }
 
+function vmm_probe_maxsmp()
+{
+	${vmm_optname[$(vmm_get_target),probe_maxsmp]} "$1"
+}
+
 function vmm_get_target()
 {
 	if [[ -z "$TARGET" ]]; then
-- 
2.50.0