commit af1724b84b7558037c665d2106ec44d7362aca6b
author Thang Tran <thuutran@amperecomputing.com> Mon Dec 09 13:37:01 2024 +0700
committer Zhikui Ren <zhikui.ren@intel.com> Wed Jan 22 01:21:01 2025 +0000
tree 4388b5f3fc437a21acc78d178a45f915c599e32c
parent 5f14cac9767afb99cd2768db2ceb9f6e9342f1fa

adcsensor: prevent reading when power is not ready

Currently, the adcsensor is reading all of the sensors even their power
state is not ready. It made the system waste more resources to read
files.

This commit checks the power state before requesting to read I/O files.
It prevents reading sensors when the power state is not ready.

Tested:
   1. Turn off the power.
      $ipmitool power off
   2. Check the adc sensors that have the "PowerState" property in
      Entity-Manager is "On"/"ChassisOn" via dbus interfaces.
   3. Those sensors have the "Available" property is "false" and the
      "Value" is "nan".
   4. The hwmon files that corresponding to those sensors are not read
   5. Turn on the power.
      $ipmitool power on
   6. Check the adc sensors that have the "PowerState" property in
      Entity-Manager is "On"/"ChassisOn" via dbus interfaces.
   7. Those sensors have the "Available" property is "true" and the
      "Value" is not "nan".

Change-Id: I52219f40fdd3b478425956c176ac40e3e16c10d1
Signed-off-by: Thang Tran <thuutran@amperecomputing.com>

src/adc/ADCSensor.cpp

diff --git a/src/adc/ADCSensor.cpp b/src/adc/ADCSensor.cpp
index 0b3fd28..170e79b 100644
--- a/src/adc/ADCSensor.cpp
+++ b/src/adc/ADCSensor.cpp
@@ -34,6 +34,7 @@
 #include <cmath>
 #include <cstddef>
 #include <iostream>
+#include <limits>
 #include <memory>
 #include <optional>
 #include <stdexcept>
@@ -104,6 +105,14 @@
 
 void ADCSensor::setupRead()
 {
+    if (!readingStateGood())
+    {
+        markAvailable(false);
+        updateValue(std::numeric_limits<double>::quiet_NaN());
+        restartRead();
+        return;
+    }
+
     std::shared_ptr<boost::asio::streambuf> buffer =
         std::make_shared<boost::asio::streambuf>();
 
@@ -158,6 +167,36 @@
     }
 }
 
+void ADCSensor::restartRead()
+{
+    std::weak_ptr<ADCSensor> weakRef = weak_from_this();
+    waitTimer.expires_after(std::chrono::milliseconds(sensorPollMs));
+    waitTimer.async_wait([weakRef](const boost::system::error_code& ec) {
+        std::shared_ptr<ADCSensor> self = weakRef.lock();
+        if (ec == boost::asio::error::operation_aborted)
+        {
+            if (self)
+            {
+                std::cerr << "adcsensor " << self->name << " read cancelled\n";
+            }
+            else
+            {
+                std::cerr << "adcsensor read cancelled no self\n";
+            }
+            return; // we're being canceled
+        }
+
+        if (self)
+        {
+            self->setupRead();
+        }
+        else
+        {
+            std::cerr << "adcsensor weakref no self\n";
+        }
+    });
+}
+
 void ADCSensor::handleResponse(const boost::system::error_code& err)
 {
     std::weak_ptr<ADCSensor> weakRef = weak_from_this();
@@ -206,31 +245,7 @@
         return; // we're no longer valid
     }
     inputDev.assign(fd);
-    waitTimer.expires_after(std::chrono::milliseconds(sensorPollMs));
-    waitTimer.async_wait([weakRef](const boost::system::error_code& ec) {
-        std::shared_ptr<ADCSensor> self = weakRef.lock();
-        if (ec == boost::asio::error::operation_aborted)
-        {
-            if (self)
-            {
-                std::cerr << "adcsensor " << self->name << " read cancelled\n";
-            }
-            else
-            {
-                std::cerr << "adcsensor read cancelled no self\n";
-            }
-            return; // we're being canceled
-        }
-
-        if (self)
-        {
-            self->setupRead();
-        }
-        else
-        {
-            std::cerr << "adcsensor weakref no self\n";
-        }
-    });
+    restartRead();
 }
 
 void ADCSensor::checkThresholds()

src/adc/ADCSensor.hpp

diff --git a/src/adc/ADCSensor.hpp b/src/adc/ADCSensor.hpp
index f562405..16d9c66 100644
--- a/src/adc/ADCSensor.hpp
+++ b/src/adc/ADCSensor.hpp
@@ -89,4 +89,5 @@
     thresholds::ThresholdTimer thresholdTimer;
     void handleResponse(const boost::system::error_code& err);
     void checkThresholds() override;
+    void restartRead();
 };