geopm::Endpoint(3) – GEOPM endpoint interface

Namespaces

The Endpoint class is a member of the namespace geopm, but the full name, geopm::Endpoint, has been abbreviated in this manual. Similarly, the std:: namespace specifier has been omitted from the interface definitions for the following standard types: std::vector, std::string, and std::set, to enable better rendering of this manual.

Note that the Endpoint class is an abstract base class. There is one concrete implementation, EndpointImp, which uses shared memory to implement the Endpoint interface functionality.

Synopsis

#include <geopm/Endpoint.hpp>

Link with -lgeopm

static unique_ptr<Endpoint> Endpoint::make_unique(const string &data_path);

virtual void Endpoint::open(void);

virtual void Endpoint::close(void);

virtual void Endpoint::write_policy(const vector<double> &policy);

virtual double Endpoint::read_sample(vector<double> &sample);

virtual string Endpoint::get_agent(void);

virtual void Endpoint::wait_for_agent_attach(double timeout);

virtual void Endpoint::wait_for_agent_detach(double timeout);

virtual void Endpoint::stop_wait_loop(void);

virtual void Endpoint::reset_wait_loop(void);

virtual string Endpoint::get_profile_name(void);

virtual set<string> Endpoint::get_hostnames(void);

Description

The Endpoint class is the underlying C++ implementation for the geopm_endpoint(3) C interface. Please refer to the geopm_endpoint(3) man page for a general description of the purpose, goals, and use cases for this interface.

Factory Method

make_unique(): This method returns a unique_ptr<Endpoint> to a concrete EndpointImp object. The shared memory prefix should be given in data_path.

Class Methods

open(): creates the underlying shared memory regions belonging to the Endpoint.
close(): unlinks the shared memory regions belonging to the Endpoint.
write_policy(): writes a set of policy values given in policy to the endpoint. The order of the values is determined by the currently attached agent; see geopm::Agent(3).
read_sample(): reads the most recent set of sample values from the endpoint into the output vector, sample, and returns the sample age in seconds. The order of the values is determined by the currently attached agent; see geopm::Agent(3).
get_agent(): returns the agent name associated with the Controller attached to this endpoint, or empty if no Controller is attached.
wait_for_agent_attach(): Blocks until an agent attaches to the endpoint, a timeout is reached, or the operation is canceled with stop_wait_loop(). Throws an exception if the given timeout is reached before an agent attaches. The name of the attached agent can be read with get_agent().
wait_for_agent_detach(): Blocks as long as the same agent is still attached to the endpoint, a timeout is reached, or the operation is canceled with stop_wait_loop(). The name of the attached agent can be read with get_agent().
stop_wait_loop(): Cancels any current wait loops in this Endpoint.
reset_wait_loop(): Re-enables wait loops occurring after this call.
get_profile_name(): returns the profile name associated with the attached job, or empty if no Controller is attached.
get_hostnames(): returns the set of hostnames used by the Controller attached to this endpoint, or empty if no Controller is attached.

Errors

All functions described on this man page throw geopm::Exception(3) on error.