remove unused ssh pipelining setters

fixes #31125

lib/ansible/config/base.yml

@@ -115,19 +115,6 @@ ANSIBLE_SSH_EXECUTABLE:
   - {key: ssh_executable, section: ssh_connection}
   yaml: {key: ssh_connection.ssh_executable}
   version_added: "2.2"
-ANSIBLE_SSH_PIPELINING:
-  # TODO: move to ssh plugin
-  default: False
-  description:
-    - Pipelining reduces the number of SSH operations required to execute a module on the remote server,
-      by executing many Ansible modules without actual file transfer.
-    - This can result in a very significant performance improvement when enabled.
-    - "However this conflicts with privilege escalation (become). For example, when using 'sudo:' operations you must first disable 'requiretty' in /etc/sudoers on all managed hosts, which is why it is disabled by default."
-  env: [{name: ANSIBLE_SSH_PIPELINING}]
-  ini:
-  - {key: pipelining, section: ssh_connection}
-  type: boolean
-  yaml: {key: ssh_connection.pipelining}
 ANSIBLE_SSH_RETRIES:
   # TODO: move to ssh plugin
   default: 0

lib/ansible/plugins/connection/ssh.py

@@ -116,11 +116,18 @@ DOCUMENTATION = '''
             - However this conflicts with privilege escalation (become).
               For example, when using sudo operations you must first disable 'requiretty' in the sudoers file for the target hosts,
               which is why this feature is disabled by default.
-          env: [{name: ANSIBLE_SSH_PIPELINING}]
+          env:
+            - name: ANSIBLE_PIPELINING
+            #- name: ANSIBLE_SSH_PIPELINING
           ini:
-          - {key: pipelining, section: ssh_connection}
+            - section: defaults
+              key: pipelining
+            #- section: ssh_connection
+            #  key: pipelining
           type: boolean
-          vars: [{name: ansible_ssh_pipelining}]
+          vars:
+            - name: ansible_pipelining
+            - name: ansible_ssh_pipelining
       private_key_file:
           description:
               - Path to private key file to use for authentication

test/legacy/Makefile

@@ -58,7 +58,7 @@ $(CREDENTIALS_FILE):
 	@exit 1
 
 amazon: $(CREDENTIALS_FILE)
-	ANSIBLE_HOST_KEY_CHECKING=False ANSIBLE_SSH_PIPELINING=no BOTO_CONFIG=/dev/null ansible-playbook amazon.yml -i $(INVENTORY) -e @$(VARS_FILE) $(CREDENTIALS_ARG) -e "resource_prefix=$(CLOUD_RESOURCE_PREFIX)" -v $(TEST_FLAGS) ; \
+	ANSIBLE_HOST_KEY_CHECKING=False ANSIBLE_PIPELINING=no BOTO_CONFIG=/dev/null ansible-playbook amazon.yml -i $(INVENTORY) -e @$(VARS_FILE) $(CREDENTIALS_ARG) -e "resource_prefix=$(CLOUD_RESOURCE_PREFIX)" -v $(TEST_FLAGS) ; \
     RC=$$? ; \
     CLOUD_RESOURCE_PREFIX="$(CLOUD_RESOURCE_PREFIX)" make amazon_cleanup ; \
     exit $$RC;