selftests: forwarding: devlink_lib: Split devlink_..._set() into save & set

Changing pool type from static to dynamic causes reinterpretation of
threshold values. They therefore need to be saved before pool type is
changed, then the pool type can be changed, and then the new values need
to be set up.

For that reason, set cannot subsume save, because it would be saving the
wrong thing, with possibly a nonsensical value, and restore would then fail
to restore the nonsensical value.

Thus extract a _save() from each of the relevant _set()'s. This way it is
possible to save everything up front, then to tweak it, and then restore in
the required order.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 51 insertions, 11 deletions

diff --git a/tools/testing/selftests/net/forwarding/devlink_lib.sh b/tools/testing/selftests/net/forwarding/devlink_lib.sh
index 75fe24bcb9cd..ba6aca848702 100644
--- a/tools/testing/selftests/net/forwarding/devlink_lib.sh
+++ b/tools/testing/selftests/net/forwarding/devlink_lib.sh
@@ -117,6 +117,12 @@ devlink_reload()
 
 declare -A DEVLINK_ORIG
 
+# Changing pool type from static to dynamic causes reinterpretation of threshold
+# values. They therefore need to be saved before pool type is changed, then the
+# pool type can be changed, and then the new values need to be set up. Therefore
+# instead of saving the current state implicitly in the _set call, provide
+# functions for all three primitives: save, set, and restore.
+
 devlink_port_pool_threshold()
 {
 	local port=$1; shift
@@ -126,14 +132,21 @@ devlink_port_pool_threshold()
 		| jq '.port_pool."'"$port"'"[].threshold'
 }
 
-devlink_port_pool_th_set()
+devlink_port_pool_th_save()
 {
 	local port=$1; shift
 	local pool=$1; shift
-	local th=$1; shift
 	local key="port_pool($port,$pool).threshold"
 
 	DEVLINK_ORIG[$key]=$(devlink_port_pool_threshold $port $pool)
+}
+
+devlink_port_pool_th_set()
+{
+	local port=$1; shift
+	local pool=$1; shift
+	local th=$1; shift
+
 	devlink sb port pool set $port pool $pool th $th
 }
 
@@ -142,8 +155,13 @@ devlink_port_pool_th_restore()
 	local port=$1; shift
 	local pool=$1; shift
 	local key="port_pool($port,$pool).threshold"
+	local -a orig=(${DEVLINK_ORIG[$key]})
 
-	devlink sb port pool set $port pool $pool th ${DEVLINK_ORIG[$key]}
+	if [[ -z $orig ]]; then
+		echo "WARNING: Mismatched devlink_port_pool_th_restore"
+	else
+		devlink sb port pool set $port pool $pool th $orig
+	fi
 }
 
 devlink_pool_size_thtype()
@@ -154,14 +172,20 @@ devlink_pool_size_thtype()
 	    | jq -r '.pool[][] | (.size, .thtype)'
 }
 
+devlink_pool_size_thtype_save()
+{
+	local pool=$1; shift
+	local key="pool($pool).size_thtype"
+
+	DEVLINK_ORIG[$key]=$(devlink_pool_size_thtype $pool)
+}
+
 devlink_pool_size_thtype_set()
 {
 	local pool=$1; shift
 	local thtype=$1; shift
 	local size=$1; shift
-	local key="pool($pool).size_thtype"
 
-	DEVLINK_ORIG[$key]=$(devlink_pool_size_thtype $pool)
 	devlink sb pool set "$DEVLINK_DEV" pool $pool size $size thtype $thtype
 }
 
@@ -171,8 +195,12 @@ devlink_pool_size_thtype_restore()
 	local key="pool($pool).size_thtype"
 	local -a orig=(${DEVLINK_ORIG[$key]})
 
-	devlink sb pool set "$DEVLINK_DEV" pool $pool \
-		size ${orig[0]} thtype ${orig[1]}
+	if [[ -z ${orig[0]} ]]; then
+		echo "WARNING: Mismatched devlink_pool_size_thtype_restore"
+	else
+		devlink sb pool set "$DEVLINK_DEV" pool $pool \
+			size ${orig[0]} thtype ${orig[1]}
+	fi
 }
 
 devlink_tc_bind_pool_th()
@@ -185,6 +213,16 @@ devlink_tc_bind_pool_th()
 	    | jq -r '.tc_bind[][] | (.pool, .threshold)'
 }
 
+devlink_tc_bind_pool_th_save()
+{
+	local port=$1; shift
+	local tc=$1; shift
+	local dir=$1; shift
+	local key="tc_bind($port,$dir,$tc).pool_th"
+
+	DEVLINK_ORIG[$key]=$(devlink_tc_bind_pool_th $port $tc $dir)
+}
+
 devlink_tc_bind_pool_th_set()
 {
 	local port=$1; shift
@@ -192,9 +230,7 @@ devlink_tc_bind_pool_th_set()
 	local dir=$1; shift
 	local pool=$1; shift
 	local th=$1; shift
-	local key="tc_bind($port,$dir,$tc).pool_th"
 
-	DEVLINK_ORIG[$key]=$(devlink_tc_bind_pool_th $port $tc $dir)
 	devlink sb tc bind set $port tc $tc type $dir pool $pool th $th
 }
 
@@ -206,8 +242,12 @@ devlink_tc_bind_pool_th_restore()
 	local key="tc_bind($port,$dir,$tc).pool_th"
 	local -a orig=(${DEVLINK_ORIG[$key]})
 
-	devlink sb tc bind set $port tc $tc type $dir \
-		pool ${orig[0]} th ${orig[1]}
+	if [[ -z ${orig[0]} ]]; then
+		echo "WARNING: Mismatched devlink_tc_bind_pool_th_restore"
+	else
+		devlink sb tc bind set $port tc $tc type $dir \
+			pool ${orig[0]} th ${orig[1]}
+	fi
 }
 
 devlink_traps_num_get()