[Mellanox] Fix issue: PSU model/serial/revision info should be updated after replacing PSU (#9040)

platform/mellanox/mlnx-platform-api/sonic_platform/psu.py

@@ -13,6 +13,7 @@ try:
     from sonic_platform.fan import Fan
     from .led import PsuLed, SharedLed, ComponentFaultyIndicator
     from .device_data import DEVICE_DATA
+    from .vpd_parser import VpdParser
 except ImportError as e:
     raise ImportError (str(e) + "- required module not found")
 
@@ -31,7 +32,7 @@ SN_VPD_FIELD = "SN_VPD_FIELD"
 PN_VPD_FIELD = "PN_VPD_FIELD"
 REV_VPD_FIELD = "REV_VPD_FIELD"
 
-# in most platforms the file psuX_curr, psuX_volt and psuX_power contain current, voltage and power data respectively. 
+# in most platforms the file psuX_curr, psuX_volt and psuX_power contain current, voltage and power data respectively.
 # but there are exceptions which will be handled by the following dictionary
 
 platform_dict_psu = {'x86_64-mlnx_msn3420-r0': 1, 'x86_64-mlnx_msn3700-r0': 1, 'x86_64-mlnx_msn3700c-r0': 1,
@@ -88,30 +89,10 @@ class Psu(PsuBase):
         self.psu_data = DEVICE_DATA[platform]['psus']
         psu_vpd = filemap[PSU_VPD]
 
-        self.model = "N/A"
-        self.serial = "N/A"
-        self.rev = "N/A"
-
         if psu_vpd is not None:
-            self.psu_vpd = os.path.join(self.psu_path, psu_vpd.format(self.index))
+            self.vpd_parser = VpdParser(os.path.join(self.psu_path, psu_vpd.format(self.index)))
-            self.vpd_data = self._read_vpd_file(self.psu_vpd)
+        else:
-
+            self.vpd_parser = None
-            if PN_VPD_FIELD in self.vpd_data:
-                self.model = self.vpd_data[PN_VPD_FIELD]
-            else:
-                logger.log_error("Fail to read PSU{} model number: No key {} in VPD {}".format(self.index, PN_VPD_FIELD, self.psu_vpd))
-
-            if SN_VPD_FIELD in self.vpd_data:
-                self.serial = self.vpd_data[SN_VPD_FIELD]
-            else:
-                logger.log_error("Fail to read PSU{} serial number: No key {} in VPD {}".format(self.index, SN_VPD_FIELD, self.psu_vpd))
-
-            if REV_VPD_FIELD in self.vpd_data:
-                self.rev = self.vpd_data[REV_VPD_FIELD]
-            else:
-                logger.log_error("Fail to read PSU{} serial number: No key {} in VPD {}".format(self.index, REV_VPD_FIELD, self.psu_vpd))
-
-        else: 
             logger.log_info("Not reading PSU{} VPD data: Platform is fixed".format(self.index))
 
         if not self.psu_data['hot_swappable']:
@@ -162,24 +143,6 @@ class Psu(PsuBase):
         return self._name
 
 
-    def _read_vpd_file(self, filename):
-        """
-        Read a vpd file parsed from eeprom with keys and values.
-        Returns a dictionary.
-        """
-        result = {}
-        try:
-            if not os.path.exists(filename):
-                return result
-            with open(filename, 'r') as fileobj:
-                for line in fileobj.readlines():
-                    key, val = line.split(":")
-                    result[key.strip()] = val.strip()
-        except Exception as e:
-            logger.log_error("Fail to read VPD file {} due to {}".format(filename, repr(e)))
-        return result
-
-
     def _read_generic_file(self, filename, len):
         """
         Read a generic file, returns the contents of the file
@@ -202,7 +165,7 @@ class Psu(PsuBase):
         Returns:
             string: Model/part number of device
         """
-        return self.model
+        return 'N/A' if self.vpd_parser is None else self.vpd_parser.get_model()
 
 
     def get_serial(self):
@@ -212,7 +175,7 @@ class Psu(PsuBase):
         Returns:
             string: Serial number of device
         """
-        return self.serial
+        return 'N/A' if self.vpd_parser is None else self.vpd_parser.get_serial()
 
 
     def get_revision(self):
@@ -222,7 +185,7 @@ class Psu(PsuBase):
         Returns:
             string: Revision value of device
         """
-        return self.rev
+        return 'N/A' if self.vpd_parser is None else self.vpd_parser.get_revision()
 
 
     def get_powergood_status(self):
@@ -256,8 +219,8 @@ class Psu(PsuBase):
         Retrieves current PSU voltage output
 
         Returns:
-            A float number, the output voltage in volts, 
+            A float number, the output voltage in volts,
-            e.g. 12.1 
+            e.g. 12.1
         """
         if self.psu_voltage is not None and self.get_powergood_status():
             voltage = self._read_generic_file(self.psu_voltage, 0)
@@ -327,7 +290,7 @@ class Psu(PsuBase):
         Gets the power available status
 
         Returns:
-            True if power is present and power on. 
+            True if power is present and power on.
             False and "absence of PSU" if power is not present.
             False and "absence of power" if power is present but not power on.
         """
@@ -366,7 +329,7 @@ class Psu(PsuBase):
 
         Returns:
             A float number of current temperature in Celsius up to nearest thousandth
-            of one degree Celsius, e.g. 30.125 
+            of one degree Celsius, e.g. 30.125
         """
         if self.psu_temp is not None and self.get_powergood_status():
             try:
@@ -374,7 +337,7 @@ class Psu(PsuBase):
                 return float(temp) / 1000
             except Exception as e:
                 logger.log_info("Fail to get temperature for PSU {} due to - {}".format(self._name, repr(e)))
-        
+
         return None
 
     def get_temperature_high_threshold(self):
@@ -391,7 +354,7 @@ class Psu(PsuBase):
                 return float(temp_threshold) / 1000
             except Exception as e:
                 logger.log_info("Fail to get temperature threshold for PSU {} due to - {}".format(self._name, repr(e)))
-        
+
         return None
 
     def get_voltage_high_threshold(self):
@@ -399,8 +362,8 @@ class Psu(PsuBase):
         Retrieves the high threshold PSU voltage output
 
         Returns:
-            A float number, the high threshold output voltage in volts, 
+            A float number, the high threshold output voltage in volts,
-            e.g. 12.1 
+            e.g. 12.1
         """
         # hw-management doesn't expose those sysfs for now
         raise NotImplementedError
@@ -410,8 +373,8 @@ class Psu(PsuBase):
         Retrieves the low threshold PSU voltage output
 
         Returns:
-            A float number, the low threshold output voltage in volts, 
+            A float number, the low threshold output voltage in volts,
-            e.g. 12.1 
+            e.g. 12.1
         """
         # hw-management doesn't expose those sysfs for now
         raise NotImplementedError

platform/mellanox/mlnx-platform-api/sonic_platform/utils.py

@@ -1,10 +1,37 @@
 import functools
 import subprocess
+from sonic_py_common.logger import Logger
+
+logger = Logger()
 
 # flags to indicate whether this process is running in docker or host
 _is_host = None
 
 
+def read_from_file(file_path, target_type, default='', raise_exception=False, log_func=logger.log_error):
+    """
+    Read content from file and convert to target type
+    :param file_path: File path
+    :param target_type: target type
+    :param default: Default return value if any exception occur
+    :param raise_exception: Raise exception to caller if True else just return default value
+    :param log_func: function to log the error
+    :return: String content of the file
+    """
+    try:
+        with open(file_path, 'r') as f:
+            value = target_type(f.read().strip())
+    except (ValueError, IOError) as e:
+        if log_func:
+            log_func('Failed to read from file {} - {}'.format(file_path, repr(e)))
+        if not raise_exception:
+            value = default
+        else:
+            raise e
+
+    return value
+
+
 def read_str_from_file(file_path, default='', raise_exception=False):
     """
     Read string content from file
@@ -45,6 +72,28 @@ def read_int_from_file(file_path, default=0, raise_exception=False):
     return value
 
 
+def _key_value_converter(content):
+    ret = {}
+    for line in content.splitlines():
+        k,v = line.split(':')
+        ret[k.strip()] = v.strip()
+    return ret
+
+
+def read_key_value_file(file_path, default={}, raise_exception=False, log_func=logger.log_error):
+    """Read file content and parse the content to a dict. The file content should like:
+       key1:value1
+       key2:value2
+
+    Args:
+        file_path (str): file path
+        default (dict, optional): default return value. Defaults to {}.
+        raise_exception (bool, optional): If exception should be raised or hiden. Defaults to False.
+        log_func (optional): logger function.. Defaults to logger.log_error.
+    """
+    return read_from_file(file_path=file_path, target_type=_key_value_converter, default=default, raise_exception=raise_exception, log_func=log_func)
+
+
 def write_file(file_path, content, raise_exception=False):
     """
     Write the given value to a file
@@ -72,13 +121,13 @@ def is_host():
     global _is_host
     if _is_host is not None:
         return _is_host
-        
+
     _is_host = False
     try:
-        proc = subprocess.Popen("docker --version 2>/dev/null", 
+        proc = subprocess.Popen("docker --version 2>/dev/null",
-                                stdout=subprocess.PIPE, 
+                                stdout=subprocess.PIPE,
-                                shell=True, 
+                                shell=True,
-                                stderr=subprocess.STDOUT, 
+                                stderr=subprocess.STDOUT,
                                 universal_newlines=True)
         stdout = proc.communicate()[0]
         proc.wait()

platform/mellanox/mlnx-platform-api/sonic_platform/vpd_parser.py

@@ -0,0 +1,84 @@
+#
+# Copyright (c) 2021 NVIDIA CORPORATION & AFFILIATES.
+# Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+import os
+from sonic_py_common.logger import Logger
+
+from . import utils
+
+logger = Logger()
+SN_VPD_FIELD = "SN_VPD_FIELD"
+PN_VPD_FIELD = "PN_VPD_FIELD"
+REV_VPD_FIELD = "REV_VPD_FIELD"
+
+
+class VpdParser:
+    def __init__(self, file_path):
+        self.vpd_data = {}
+        self.vpd_file = file_path
+        self.vpd_file_last_mtime = None
+
+    def _get_data(self):
+        if not os.path.exists(self.vpd_file):
+            self.vpd_data = {}
+            return False
+
+        try:
+            mtime = os.stat(self.vpd_file).st_mtime
+            if mtime != self.vpd_file_last_mtime:
+                self.vpd_file_last_mtime = mtime
+                self.vpd_data = utils.read_key_value_file(self.vpd_file)
+            return True
+        except Exception as e:
+            self.vpd_data = {}
+            return False
+
+    def get_model(self):
+        """
+        Retrieves the model number (or part number) of the device
+
+        Returns:
+            string: Model/part number of device
+        """
+        if self._get_data() and PN_VPD_FIELD not in self.vpd_data:
+            logger.log_error("Fail to read model number: No key {} in VPD {}".format(PN_VPD_FIELD, self.vpd_file))
+            return 'N/A'
+        return self.vpd_data.get(PN_VPD_FIELD, 'N/A')
+
+    def get_serial(self):
+        """
+        Retrieves the serial number of the device
+
+        Returns:
+            string: Serial number of device
+        """
+        if self._get_data() and SN_VPD_FIELD not in self.vpd_data:
+            logger.log_error("Fail to read serial number: No key {} in VPD {}".format(SN_VPD_FIELD, self.vpd_file))
+            return 'N/A'
+        return self.vpd_data.get(SN_VPD_FIELD, 'N/A')
+
+    def get_revision(self):
+        """
+        Retrieves the hardware revision of the device
+
+        Returns:
+            string: Revision value of device
+        """
+        if self._get_data() and REV_VPD_FIELD not in self.vpd_data:
+            logger.log_error("Fail to read revision: No key {} in VPD {}".format(REV_VPD_FIELD, self.vpd_file))
+            return 'N/A'
+        return self.vpd_data.get(REV_VPD_FIELD, 'N/A')