[Mellanox] make sure shared storage with syncd is cleared on restarts

files/build_templates/docker_image_ctl.j2

@@ -157,9 +157,9 @@ function waitForAllInstanceDatabaseConfigJsonFilesReady()
             done
         fi
         # Delay a second to allow all instance database_config.json files to be completely generated and fully accessible.
-        # This delay is needed to make sure that the database_config.json files are correctly rendered from j2 template 
+        # This delay is needed to make sure that the database_config.json files are correctly rendered from j2 template
         # files ( renderning takes some time )
-        sleep 1 
+        sleep 1
     fi
 }
 {%- endif %}
@@ -240,7 +240,7 @@ function postStartAction()
             mv $WARM_DIR/dump.rdb $WARM_DIR/dump.rdb.old
         else
             # If there is a config_db.json dump file, load it.
-            if [ -r /etc/sonic/config_db$DEV.json ]; then		
+            if [ -r /etc/sonic/config_db$DEV.json ]; then
 
                 if [ -r /etc/sonic/init_cfg.json ]; then
                     $SONIC_CFGGEN -j /etc/sonic/init_cfg.json -j /etc/sonic/config_db$DEV.json --write-to-db
@@ -323,7 +323,7 @@ start() {
 
     {%- if sonic_asic_platform == "broadcom" %}
     {%- if docker_container_name == "syncd" %}
-    # Set the SYNCD_SHM_SIZE if this variable not defined    
+    # Set the SYNCD_SHM_SIZE if this variable not defined
     BRCM_PLATFORM_COMMON_DIR=/usr/share/sonic/device/x86_64-broadcom_common
     SYNCD_SHM_INI=$BRCM_PLATFORM_COMMON_DIR/syncd_shm.ini
 
@@ -530,14 +530,15 @@ start() {
 {%- if docker_container_name == "syncd" %}
         -v /var/log/mellanox:/var/log/mellanox:rw \
         -v mlnx_sdk_socket:/var/run/sx_sdk \
-        -v mlnx_sdk_ready:/tmp \
+        -v /tmp/nv-syncd-shared/:/tmp \
         -v /dev/shm:/dev/shm:rw \
         -v /var/log/sai_failure_dump:/var/log/sai_failure_dump:rw \
         -e SX_API_SOCKET_FILE=/var/run/sx_sdk/sx_api.sock \
 {%- elif docker_container_name == "pmon" %}
         -v /var/run/hw-management:/var/run/hw-management:rw \
         -v mlnx_sdk_socket:/var/run/sx_sdk \
-        -v mlnx_sdk_ready:/tmp \
+        -v /tmp/nv-syncd-shared/:/tmp \
+        -v /dev/shm:/dev/shm:rw \
         -e SX_API_SOCKET_FILE=/var/run/sx_sdk/sx_api.sock \
         -v /dev/shm:/dev/shm:rw \
 {%- else %}

files/build_templates/per_namespace/syncd.service.j2

@@ -19,6 +19,10 @@ After=updategraph.service
 BindsTo=sonic.target
 After=sonic.target
 Before=ntp-config.service
+{% if sonic_asic_platform == 'mellanox' %}
+Requires=nv-syncd-shared.service
+After=nv-syncd-shared.service
+{% endif %}
 
 [Service]
 User=root

files/build_templates/sonic_debian_extension.j2

@@ -953,6 +953,10 @@ MLNX_SONIC_PLATFORM_PY3_WHEEL_NAME=$(basename {{mlnx_platform_api_py3_wheel_path
 sudo cp {{mlnx_platform_api_py3_wheel_path}} $FILESYSTEM_ROOT/$MLNX_SONIC_PLATFORM_PY3_WHEEL_NAME
 sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install $MLNX_SONIC_PLATFORM_PY3_WHEEL_NAME
 sudo rm -rf $FILESYSTEM_ROOT/$MLNX_SONIC_PLATFORM_PY3_WHEEL_NAME
+
+# Install service that manages Nvidia specific shared storage
+sudo cp platform/mellanox/nv-syncd-shared/nv-syncd-shared.service $FILESYSTEM_ROOT_USR_LIB_SYSTEMD_SYSTEM/
+sudo LANG=C chroot $FILESYSTEM_ROOT systemctl enable nv-syncd-shared
 {% endif %}
 
 {%- if SONIC_ROUTING_STACK == "frr" %}

platform/mellanox/nv-syncd-shared/nv-syncd-shared.service

@@ -0,0 +1,17 @@
+[Unit]
+Description=Manage Nvidia specific syncd shared volume
+Requires=docker.service
+After=docker.service
+BindsTo=sonic.target
+After=sonic.target
+PartOf=syncd.service
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=rm -rf /tmp/nv-syncd-shared/
+ExecStart=mkdir -p /tmp/nv-syncd-shared/
+
+[Install]
+WantedBy=sonic.target
+