Fix post-reboot errors in platforms without sonic_platform package (#6130)

Refactor determine-reboot cause code. Fix errors seen during determine-reboot-cause when sonic_platform package is not installed.
Add error handling for healthd service when sonic_platform package is not installed.

Tested on KVM where sonic_platform is not present, and the errors are not seen anymore in syslog.

src/sonic-host-services/scripts/determine-reboot-cause

@@ -40,7 +40,8 @@ REBOOT_TYPE_KEXEC_PATTERN_WARM = ".*SONIC_BOOT_TYPE=(warm|fastfast).*"
 REBOOT_TYPE_KEXEC_PATTERN_FAST = ".*SONIC_BOOT_TYPE=(fast|fast-reboot).*"
 
 REBOOT_CAUSE_UNKNOWN = "Unknown"
-
+REBOOT_CAUSE_NON_HARDWARE = "Non-Hardware"
+REBOOT_CAUSE_HARDWARE_OTHER = "Hardware - Other"
 
 # Global logger class instance
 sonic_logger = logger.Logger(SYSLOG_IDENTIFIER)
@@ -98,43 +99,27 @@ def find_proc_cmdline_reboot_cause():
 
     return proc_cmdline_reboot_cause
 
-def get_reboot_cause_from_platform():
+
-    # Until all platform vendors have provided sonic_platform packages,
+def find_hardware_reboot_cause():
-    # if there is no sonic_platform package installed, we only provide
+    # Find hardware reboot cause using sonic_platform library
-    # software-related reboot causes.
     try:
         import sonic_platform
         platform  = sonic_platform.platform.Platform()
         chassis  = platform.get_chassis()
-        return chassis.get_reboot_cause()
+        hardware_reboot_cause_major, hardware_reboot_cause_minor = chassis.get_reboot_cause()
-    except ImportError as err:
-        sonic_logger.log_warning("sonic_platform package not installed. Unable to detect hardware reboot causes.")
-
-
-def find_hardware_reboot_cause():
-    hardware_reboot_cause = None
-
-    REBOOT_CAUSE_HARDWARE_OTHER = "Hardware - Other"
-    REBOOT_CAUSE_NON_HARDWARE = "Non-Hardware"
-
-    hardware_reboot_cause_major, hardware_reboot_cause_minor = get_reboot_cause_from_platform()
         sonic_logger.log_info("Platform api returns reboot cause {}, {}".format(hardware_reboot_cause_major, hardware_reboot_cause_minor))
+    except ImportError:
+        sonic_logger.log_warning("sonic_platform package not installed. Unable to detect hardware reboot causes.")
+        hardware_reboot_cause_major, hardware_reboot_cause_minor = REBOOT_CAUSE_NON_HARDWARE, "N/A"
 
-    if hardware_reboot_cause_major == REBOOT_CAUSE_NON_HARDWARE:
+    if hardware_reboot_cause_major:
-        # The reboot was not caused by hardware. If there is a REBOOT_CAUSE_FILE, it will
+        sonic_logger.log_info("Platform api indicates reboot cause {}".format(hardware_reboot_cause_major))
-        # contain any software-related reboot info. We will use it as the previous cause.
-        pass
-    elif hardware_reboot_cause_major == REBOOT_CAUSE_HARDWARE_OTHER:
-        hardware_reboot_cause = "{} ({})".format(hardware_reboot_cause_major, hardware_reboot_cause_minor)
-    else:
-        hardware_reboot_cause = hardware_reboot_cause_major
-
-    if hardware_reboot_cause:
-        sonic_logger.log_info("Platform api indicates reboot cause {}".format(hardware_reboot_cause))
     else:
         sonic_logger.log_info("No reboot cause found from platform api")
 
-    return hardware_reboot_cause, hardware_reboot_cause_minor
+    hardware_reboot_cause = "{} ({})".format(hardware_reboot_cause_major, hardware_reboot_cause_minor)
+    return hardware_reboot_cause
+
 
 def get_reboot_cause_dict(previous_reboot_cause, comment, gen_time):
     # resultant dictionary
@@ -175,14 +160,16 @@ def main():
         os.remove(PREVIOUS_REBOOT_CAUSE_FILE)
 
     hardware_reboot_cause = None
-    additional_reboot_info = None
+    # This variable is kept for future-use purpose. When proc_cmd_line/vendor/software provides
+    # any additional_reboot_info it will be stored as a "comment" in REBOOT_CAUSE_HISTORY_FILE
+    additional_reboot_info = "N/A"
 
     # 1. Check if the previous reboot was warm/fast reboot by testing whether there is "fast|fastfast|warm" in /proc/cmdline
     proc_cmdline_reboot_cause = find_proc_cmdline_reboot_cause()
 
     # 2. Check if the previous reboot was caused by hardware
     #    If yes, the hardware reboot cause will be treated as the reboot cause
-    (hardware_reboot_cause, additional_reboot_info) = find_hardware_reboot_cause()
+    hardware_reboot_cause = find_hardware_reboot_cause()
 
     # 3. If there is a REBOOT_CAUSE_FILE, it will contain any software-related
     #    reboot info. We will use it as the previous cause.
@@ -197,7 +184,7 @@ def main():
     # Else the software_reboot_cause will be treated as the reboot cause
     if proc_cmdline_reboot_cause is not None:
         previous_reboot_cause = software_reboot_cause
-    elif hardware_reboot_cause is not None:
+    elif hardware_reboot_cause is not REBOOT_CAUSE_NON_HARDWARE:
         previous_reboot_cause = hardware_reboot_cause
     else:
         previous_reboot_cause = software_reboot_cause

src/sonic-host-services/tests/determine-reboot-cause_test.py

@@ -99,9 +99,8 @@ class TestDetermineRebootCause(object):
             assert result == "fast-reboot"
 
     def test_find_hardware_reboot_cause(self):
-        with mock.patch("determine_reboot_cause.get_reboot_cause_from_platform", return_value=("Powerloss", None)):
         result = find_hardware_reboot_cause()
-            assert result == ("Powerloss", None)
+        assert result == "Non-Hardware (N/A)"
 
     def test_get_reboot_cause_dict_watchdog(self):
         reboot_cause_dict = get_reboot_cause_dict(REBOOT_CAUSE_WATCHDOG, "", GEN_TIME_WATCHDOG) 
@@ -113,5 +112,5 @@ class TestDetermineRebootCause(object):
 
     @classmethod
     def teardown_class(cls):
-        print("TREARDOWN")
+        print("TEARDOWN")
 

src/system-health/scripts/healthd

@@ -68,6 +68,7 @@ class HealthDaemon(DaemonBase):
         """
         self.log_notice("Starting up...")
 
+        try:
             import sonic_platform.platform
             chassis = sonic_platform.platform.Platform().get_chassis()
             manager = HealthCheckerManager()
@@ -81,6 +82,8 @@ class HealthDaemon(DaemonBase):
 
                 if self.stop_event.wait(manager.config.interval):
                     break
+        except ImportError:
+            self.log_warning("sonic_platform package not installed. Cannot start system-health daemon")
 
         self.deinit()