pseq: Add presence caching to Services
Add caching of hardware presence data to the Services class in the
phosphor-power-sequencer application. Obtaining hardware presence from
D-Bus is a slow operation. During pgood fault isolation, multiple rails
may need the same hardware presence information. Cache this information
to improve performance.
Provide a method to clear the cached data since it is only valid for a
short period of time. For example, power supplies are hot-pluggable, so
their presence may change while a system is powered on.
Tested:
* BMCServices
* createPMBus()
* Verify correct sysfs path passed to PMBus constructor
* isPresent()
* Test where hardware is present
* Test where value is not cached
* Verify value is cached after data obtained from D-Bus
* Test where value is cached
* Test where hardware is not present
* Test where value is not cached
* Verify value is cached after data obtained from D-Bus
* Test where value is cached
* Test where D-Bus method call fails with an expected exception
* Verify false is stored in cache
* Verify false is returned
* Test where D-Bus method call fails with an unexpected exception
* Verify nothing is cached
* Verify exception is re-thrown
* clearCache()
* Verify clears all cached data
* MockServices
* Verify all methods can be called from an automated test
* Run existing automated tests
Change-Id: I3e92be3ded1ed333acbedc970409176cabe98c09
Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
diff --git a/phosphor-power-sequencer/src/services.hpp b/phosphor-power-sequencer/src/services.hpp
index 743c034..255e2c5 100644
--- a/phosphor-power-sequencer/src/services.hpp
+++ b/phosphor-power-sequencer/src/services.hpp
@@ -18,13 +18,12 @@
#include "pmbus.hpp"
#include "xyz/openbmc_project/Logging/Entry/server.hpp"
-#include <fmt/format.h>
-
#include <phosphor-logging/lg2.hpp>
#include <sdbusplus/bus.hpp>
#include <sdbusplus/exception.hpp>
#include <cstdint>
+#include <format>
#include <map>
#include <memory>
#include <string>
@@ -127,6 +126,15 @@
createPMBus(uint8_t bus, uint16_t address,
const std::string& driverName = "",
size_t instance = 0) = 0;
+
+ /**
+ * Clear any cached data.
+ *
+ * Some data may be cached for performance reasons, such as hardware
+ * presence. Clearing the cache results in the latest data being obtained
+ * by a subsequent method calls.
+ */
+ virtual void clearCache() = 0;
};
/**
@@ -188,11 +196,17 @@
const std::string& driverName = "",
size_t instance = 0) override
{
- std::string path = fmt::format("/sys/bus/i2c/devices/{}-{:04x}", bus,
+ std::string path = std::format("/sys/bus/i2c/devices/{}-{:04x}", bus,
address);
return std::make_unique<PMBus>(path, driverName, instance);
}
+ /** @copydoc Services::clearCache() */
+ virtual void clearCache() override
+ {
+ presenceCache.clear();
+ }
+
private:
/**
* Returns whether the specified D-Bus exception is one of the expected
@@ -206,6 +220,13 @@
* D-Bus bus object.
*/
sdbusplus::bus_t& bus;
+
+ /**
+ * Cached presence data.
+ *
+ * Map from inventory paths to presence values.
+ */
+ std::map<std::string, bool> presenceCache{};
};
} // namespace phosphor::power::sequencer