GEOPM_DAEMON(3)

NAME
geopm_daemon - helpers for GEOPM daemons

SYNOPSIS

#include <geopm_daemon.h>

Link with -lgeopm

int geopm_daemon_create(const char *endpoint_name,
                        const char *policystore_path,
                        struct geopm_daemon_c **daemon);
int geopm_daemon_destroy(struct geopm_daemon_c *daemon);
int geopm_daemon_update_endpoint_from_policystore(struct geopm_daemon_c *daemon,
                                                  double timeout);
int geopm_daemon_stop_wait_loop(struct geopm_daemon_c *daemon);
int geopm_daemon_reset_wait_loop(struct geopm_daemon_c *daemon);

DESCRIPTION

The geopm_daemon_c interface contains common high-level utility functions for interacting with the GEOPM Endpoint. Its main purpose is to provide the functionality needed for system resource manager plugins or daemon processes, as well as handling clean up tasks. The underlying objects used by the daemon can also be used separately; refer to geopm_endpoint(3) and geopm_policystore(3) for more information.

All functions described in this man page return an error code on failure and zero upon success; see ERRORS section below for details.

•   geopm_daemon_create(): will create a daemon object. This object will hold the necessary state for interfacing with the endpoint and policystore. The daemon object is stored in daemon and will be used with other functions in this interface. The shared memory regions managed by the internal endpoint will be created with the shmem key endpoint_name. This will return zero on success indicating that the daemon struct can now be used. daemon will be unmodified if an error occurs.

•   geopm_daemon_destroy(): will release resources associated with daemon. This will return zero on success indicating that the underlying endpoint and policystore connections were destroyed. Otherwise an error code is returned. This method removes any shared memory regions associated with the endpoint.

•   geopm_daemon_update_endpoint_from_policystore(): looks up a policy in the PolicyStore given the attached Controller's agent and profile name, and writes it back into the policy side of the Endpoint. The PolicyStore connection and Endpoint are owned by the given daemon object. If no policy is found, an error is returned. If the Controller fails to attach within the timeout, or detaches while this function is running, no policy is written.

•   geopm_daemon_stop_wait_loop(): exits early from any ongoing wait loops in the daemon, for example in a call to geopm_daemon_update_endpoint_from_policystore().

•   geopm_daemon_reset_wait_loop(): resets the daemon's endpoint to prepare for a future wait loop.

ERRORS

All functions described on this man page return an error code. See geopm_error(3) for a full description of the error numbers and how to convert them to strings.

SEE ALSO

geopm(7), geopm_error(3), geopm_endpoint(3), geopm_policystore(3), geopm::Daemon(3), geopm::Endpoint(3),

AUTHOR
Christopher Cantalupo, Brad Geltz, Konstantin Rebrov

COPYRIGHT
2015 - 2023, Intel Corporation. All rights reserved.