nvme: use async operation for PIPE write The default pipe buffer size is 16 pages (a.k.a 65,536 bytes). If the telemetry size is larger that the buffer, then the pipe write will become blocking until the client read from it. Using async write will free the blocking of main thread regardless the telemetry size and client behavior. Also the read end of PIPE now release after a timer(5 seconds). It will give the client more time to duplicate the fd before the pipe get released, in case the client is busy. Tested: Run dnvme stress test for 10 hours on izumi + A1 machine. And found no issue. Google-Bug-Id: 377742542 Signed-off-by: Hao Jiang <jianghao@google.com> Change-Id: Ife4cef3b0f01c8ab9f0194860783a9940255b947
dbus-sensors is a collection of sensor applications that provide the xyz.openbmc_project.Sensor collection of interfaces. They read sensor values from hwmon, d-bus, or direct driver access to provide readings. Some advance non-sensor features such as fan presence, pwm control, and automatic cpu detection (x86) are also supported.
runtime re-configurable from d-bus (entity-manager or the like)
isolated: each sensor type is isolated into its own daemon, so a bug in one sensor is unlikely to affect another, and single sensor modifications are possible
async single-threaded: uses sdbusplus/asio bindings
multiple data inputs: hwmon, d-bus, direct driver access
A typical dbus-sensors object support the following dbus interfaces:
Path /xyz/openbmc_project/sensors/<type>/<sensor_name>
Interfaces xyz.openbmc_project.Sensor.Value
xyz.openbmc_project.Sensor.Threshold.Critical
xyz.openbmc_project.Sensor.Threshold.Warning
xyz.openbmc_project.State.Decorator.Availability
xyz.openbmc_project.State.Decorator.OperationalStatus
xyz.openbmc_project.Association.Definitions
Sensor interfaces collection are described here.
Consumer examples of these interfaces are Redfish, Phosphor-Pid-Control, IPMI SDR.
dbus-sensor daemons are reactors that dynamically create and update sensors configuration when system configuration gets updated.
Using asio timers and async calls, dbus-sensor daemons read sensor values and check thresholds periodically. PropertiesChanged signals will be broadcasted for other services to consume when value or threshold status change. OperationStatus is set to false if the sensor is determined to be faulty.
A simple sensor example can be found here.
Sensor devices are described using Exposes records in configuration file. Name and Type fields are required. Different sensor types have different fields. Refer to entity manager schema for complete list.