rocm-systems/include/rdc/rdc.h

/*
Copyright (c) 2020 - present Advanced Micro Devices, Inc. All rights reserved.

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*/

#ifndef INCLUDE_RDC_RDC_H_
#define INCLUDE_RDC_RDC_H_

#ifdef __cplusplus
extern "C" {
#endif  // __cplusplus

#include <cstdint>

/** \file rdc_lib.h
 *  Main header file for the ROCm RDC library.
 *  All required function, structure, enum, etc. definitions should be defined
 *  in this file.
 *
 *  @brief The rocm_rdc library api is new, and therefore subject to change
 *  either at the ABI or API level. Instead of marking every function prototype
 *  as "unstable", we areinstead saying the API is unstable (i.e., changes
 *  are possible) while the major version remains 0. This means that if the
 *  API/ABI changes, we will not increment the major version to 1. Once the
 *  ABI stabilizes, we will increment the major version to 1, and thereafter
 *  increment it on all ABI breaks.
 */

/**
 * @brief Error codes returned by rocm_rdc_lib functions
 */
typedef enum {
     RDC_ST_OK                  = 0,
     RDC_ST_NOT_SUPPORTED,           //!< Not supported feature
     RDC_ST_MSI_ERROR,               //!< The MSI library error
     RDC_ST_FAIL_LOAD_MODULE,        //!< Fail to load the library
     RDC_ST_INVALID_HANDLER,         //!< Invalid handler
     RDC_ST_BAD_PARAMETER,      //!< A parameter is invalid
     RDC_ST_NOT_FOUND,          //!< Cannot find the value
     RDC_ST_CONFLICT,           //!< Conflict with current state
     RDC_ST_CLIENT_ERROR,       //!< The RDC client error
     RDC_ST_ALREADY_EXIST,      //!< The item already exists
     RDC_ST_MAX_LIMIT               //!< Max limit recording for the object
} rdc_status_t;

/**
 * @brief rdc operation mode
 * rdc can run in auto mode where background threads will collect metrics.
 * When run in manual mode, the user needs to periodically call
 * rdc_field_update_all for data collection.
 */
typedef enum {
    RDC_OPERATION_MODE_AUTO   = 0,
    RDC_OPERATION_MODE_MANUAL
} rdc_operation_mode_t;

/**
 * @brief type of GPU group
 */
typedef enum {
    RDC_GROUP_DEFAULT = 0,      //!< All GPUs on the Node
    RDC_GROUP_EMPTY             //!< Empty group
} rdc_group_type_t;

/**
 * @brief the type stored in the filed value
 */
typedef enum {
     INTEGER = 0,
     DOUBLE,
     STRING,
     BLOB
} rdc_field_type_t;


#define GPU_ID_INVALID          -1
#define RDC_GROUP_ALL_GPUS      -1000
#define RDC_JOB_STATS_FIELDS    -1000

/**
 * @brief The max rdc field string length
 */
#define RDC_MAX_STR_LENGTH      256

/**
 * @brief The max entities in a group
 */
#define RDC_GROUP_MAX_ENTITIES  64

/**
 * @brief Max number of GPUs supported by RDC
 */
#define RDC_MAX_NUM_DEVICES     16

/**
 * @brief The max fields in a field group
 */
#define RDC_MAX_FIELD_IDS_PER_FIELD_GROUP 128

/**
 * @brief The max number of groups
 */
#define RDC_MAX_NUM_GROUPS      64

/**
 * @brief The max number of the field groups
 */
#define RDC_MAX_NUM_FIELD_GROUPS 64

/**
 * @biref The fields
 */

/**
 * Memory usage of the GPU instance
 */
#define RDC_FI_GPU_MEMORY_USAGE             525

/**
 * Total memory of the GPU instance
 */
#define RDC_FI_GPU_MEMORY_TOTAL             580

/**
 * Power usage for the device
 */
#define RDC_FI_POWER_USAGE                  155

/**
 * SM clock for the GPU
 */
#define RDC_FI_GPU_SM_CLOCK                 100

/**
 * Clock for the memory
 */
#define RDC_FI_MEM_CLOCK                101

/**
 * PCIe Tx utilization information
 */
#define RDC_FI_PCIE_TX    200

/**
 * PCIe Rx utilization information
 */
#define RDC_FI_PCIE_RX    201


/**
 * GPU Utilization
 */
#define RDC_FI_GPU_UTIL                     203

/**
 * Accumulated correctable ECC errors
 */
#define RDC_FI_ECC_CORRECT_TOTAL        312

/**
 * Accumulated uncorrectable ECC errors
 */
#define RDC_FI_ECC_UNCORRECT_TOTAL      313

/**
 * Memory temperature for the device
 */
#define RDC_FI_MEMORY_TEMP           140

/**
 * Current temperature for the device
 */
#define RDC_FI_GPU_TEMP                     150


/**
 * GPU count in the system
 */
#define RDC_FI_GPU_COUNT                    4

/**
 * Name of the device
 */
#define RDC_FI_DEV_NAME                     50


/**
 * @brief handlers used in various rdc calls
 */
typedef void *rdc_handle_t;
typedef uint32_t rdc_gpu_group_t;
typedef uint32_t rdc_field_grp_t;

/**
 * @brief Represents attributes corresponding to a device
 */
typedef struct {
    char  device_name[RDC_MAX_STR_LENGTH];     //!< Name of the device.
} rdc_device_attributes_t;

/**
 * @brief The structure to store the group info
 */
typedef struct {
    unsigned int count;     //!< count of GPUs in the group
    char group_name[RDC_MAX_STR_LENGTH];     //!< group name
    /**
    * The list of entities in the group
    */
    uint32_t entity_ids[RDC_GROUP_MAX_ENTITIES];
} rdc_group_info_t;

/**
 * @brief The structure to store summary of data
 */
typedef struct {
    uint64_t max_value;
    uint64_t min_value;
    uint64_t average;
} rdc_stats_summary_t;

/**
 * @brief The structure to hold the GPU usage information
 */
typedef struct {
    uint32_t gpu_id;        //!< GPU_ID_INVALID for summary information
    uint64_t start_time;    //!< The time to start the watching
    uint64_t end_time;      //!< The time to stop the watching

    uint64_t energy_consumed;
    uint64_t ecc_correct;
    uint64_t ecc_uncorrect;
    rdc_stats_summary_t pcie_tx;
    rdc_stats_summary_t pcie_rx;
    rdc_stats_summary_t power_usage;
    rdc_stats_summary_t gpu_clock;
    rdc_stats_summary_t memory_clock;
    rdc_stats_summary_t gpu_utilization;
    rdc_stats_summary_t gpu_temperature;

    uint64_t max_gpu_memory_used;
    rdc_stats_summary_t memory_utilization;
} rdc_gpu_usage_info_t;

/**
 * @brief The structure to hold the job stats
 */
typedef struct {
     uint32_t num_gpus;
     rdc_gpu_usage_info_t summary;
     rdc_gpu_usage_info_t gpus[16];
} rdc_job_info_t;

/**
 * @brief The structure to store the field value
 */
typedef struct {
    uint32_t     field_id;      //!< The field id of the value
    int     status;             //!< RDC_ST_OK or error status
    uint64_t ts;                 //!< Timestamp in usec since 1970
    rdc_field_type_t type;      //!< The field type
    union {
        int64_t l_int;
        double  dbl;
        char str[RDC_MAX_STR_LENGTH];
    } value;
} rdc_field_value;

/**
 * @brief The structure to store the field group info
 */
typedef struct {
    uint32_t count;                      //!< count of fields in the group
    char group_name[RDC_MAX_STR_LENGTH];     //!< field group name
    /**
     * The list of fields in the group
     */
    uint32_t field_ids[RDC_MAX_FIELD_IDS_PER_FIELD_GROUP];
} rdc_field_group_info_t;

/**
 * @brief The structure to store the job info
 */
typedef struct {
    char job_id[RDC_MAX_STR_LENGTH];            //!< job id
    rdc_gpu_group_t group_id;                   //!< group name
    uint64_t start_time;                         //!< job start time
    uint64_t stop_time;                          //!< job stop time
} rdc_job_group_info_t;


/**
 *  @brief Initialize ROCm RDC.
 *
 *  @details When called, this initializes internal data structures,
 *  including those corresponding to sources of information that RDC provides.
 *  This must be called before rdc_start_embedded() or rdc_connect()
 *
 *  @param[in] init_flags init_flags Bit flags that tell RDC how to initialize.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_init(uint64_t init_flags);

/**
 *  @brief Shutdown ROCm RDC.
 *
 *  @details Do any necessary clean up.
 */
rdc_status_t rdc_shutdown();

/**
 *  @brief Start embedded RDC agent within this process.
 *
 *  @details The RDC is loaded as library so that it does not require rdcd
 *  daemon. In this mode, the user has to periodically call
 *  rdc_field_update_all() when op_mode is RDC_OPERATION_MODE_MANUAL, which
 *  tells RDC to collect the stats.
 *
 *  @param[in] op_mode Operation modes. When RDC_OPERATION_MODE_AUTO, RDC schedules
 *  background task to collect the stats. When RDC_OPERATION_MODE_MANUAL, the user
 *  needs to call rdc_field_update_all() periodically.
 *
 *  @param[inout] p_rdc_handle Caller provided pointer to rdc_handle_t. Upon
 *  successful call, the value will contain the handler for following API calls.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_start_embedded(rdc_operation_mode_t op_mode,
                                    rdc_handle_t* p_rdc_handle);

/**
 *  @brief Stop embedded RDC agent.
 *
 *  @details Stop the embedded RDC agent, and p_rdc_handle becomes
 *  invalid after this call.
 *
 *  @param[in] p_rdc_handle The RDC handler that come from
 *  rdc_start_embedded().
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_stop_embedded(rdc_handle_t p_rdc_handle);

/**
 *  @brief Connect to rdcd daemon
 *
 *  @details This method is used to connect to a remote stand-alone
 *  rdcd daemon.
 *
 *  @param[in] ipAndPort The IP and port of the remote rdcd. The ipAndPort
 *  can be specified in this x.x.x.x:yyyy format, where x.x.x.x is the
 *  IP address and yyyy is the port.
 *
 *  @param [in] root_ca The root CA stored in the string in pem format. Set it
 *  as nullptr if the communication is not encrypted.
 *
 *  @param [in] client_cert The client certificate stored in the string in pem
 *  format. Set it as nullptr if the communication is not encrypted.
 *
 *  @param [in] root_ca The client key stored in the string in pem format.
 *  Set it as nullptr if the communication is not encrypted.
 *
 *  @param[inout] p_rdc_handle Caller provided pointer to rdc_handle_t. Upon
 *  successful call, the value will contain the handler
 *  for following API calls.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_connect(const char *ipAndPort, rdc_handle_t* p_rdc_handle,
        const char* root_ca, const char* client_cert, const char* client_key);

/**
 *  @brief Disconnect from rdcd daemon.
 *
 *  @details Disconnect from rdcd daemon, and p_rdc_handle becomes invalid
 *  after this call.
 *
 *  @param[in] p_rdc_handle The RDC handler that come from rdc_connect().
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_disconnect(rdc_handle_t p_rdc_handle);

/**
 *  @brief Request the RDC to watch the job stats
 *
 *  @details This should be executed as part of job prologue. The summary
 *  job stats can be retrieved using rdc_job_get_stats().
 *  In RDC_OPERATION_MODE_MANUAL, user must call rdc_field_update_all(1)
 *  at least once, before call rdc_job_get_stats()
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] group_id The group of GPUs to be watched.
 *
 *  @param[in] job_id The name of the job.
 *
 *  @param[in] update_freq  How often to update this field in usec.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_job_start_stats(rdc_handle_t p_rdc_handle,
    rdc_gpu_group_t group_id, char job_id[64], uint64_t update_freq);

/**
 *  @brief Get the stats of the job using the job id.
 *
 *  @details The stats can be retrieved at any point when the job is in
 *  process.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] job_id The name of the job.
 *
 *  @param[inout] p_job_info Caller provided pointer to rdc_job_info_t. Upon
 *  successful call, the value will contain the stats of the job.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_job_get_stats(rdc_handle_t p_rdc_handle, char  job_id[64],
                rdc_job_info_t* p_job_info);

/**
 *  @brief Request RDC to stop watching the stats of the job
 *
 *  @details This should be execute as part of job epilogue. The job Id
 *  remains available to view the stats at any point. You must call
 *  rdc_watch_job_fields() before this call.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] job_id The name of the job.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_job_stop_stats(rdc_handle_t p_rdc_handle,
            char  job_id[64]);

/**
 *  @brief Request RDC to stop tracking the job given by job_id
 *
 *  @details After this call, you will no longer be able to call
 *  rdc_job_get_stats() on this job_id. But you will be able to reuse
 *  the job_id after this call.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] job_id The name of the job.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_job_remove(rdc_handle_t p_rdc_handle,
            char  job_id[64]);

/**
 *  @brief Request RDC to stop tracking all the jobs
 *
 *  @details After this call, you will no longer be able to call
 *  rdc_job_get_stats() on any job id. But you will be able to reuse
 *  the any previous used job id after this call.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_job_remove_all(rdc_handle_t p_rdc_handle);

/**
 *  @brief Request RDC to update all fields to be watched.
 *
 *  @details In RDC_OPERATION_MODE_MANUAL, the user must call this method
 *  periodically.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] wait_for_update Whether or not to wait for the update loop to
 *  complete before returning to the caller 1=wait. 0=do not wait.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_field_update_all(rdc_handle_t p_rdc_handle,
                    uint32_t wait_for_update);

/**
 *  @brief Get indexes corresponding to all the devices on the system.
 *
 *  @details Indexes represents RDC GPU Id corresponding to each GPU on the
 * system and is immutable during the lifespan of the engine. The list
 * should be queried again if the engine is restarted.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[out] gpu_index_list Array reference to fill GPU indexes present on
 *  the system.
 *
 *  @param[out] count Number of GPUs returned in gpu_index_list.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_device_get_all(rdc_handle_t p_rdc_handle,
            uint32_t gpu_index_list[RDC_MAX_NUM_DEVICES], uint32_t* count);

/**
 *  @brief Gets device attributes corresponding to the gpu_index.
 *
 *  @details Fetch the attributes, such as device name, of a GPU.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] gpu_index GPU index corresponding to which the attributes
 *  should be fetched
 *
 *  @param[out] p_rdc_attr GPU attribute corresponding to the gpu_index.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_device_get_attributes(rdc_handle_t p_rdc_handle,
            uint32_t gpu_index, rdc_device_attributes_t* p_rdc_attr);

/**
 *  @brief Create a group contains multiple GPUs
 *
 *  @details This method can create a group contains multiple GPUs. Instead of
 *  executing an operation separately for each GPU, the RDC group enables
 *  the user to execute same operation on all the GPUs present in the group as
 *  a single API call.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] type The type of the group. RDC_GROUP_DEFAULT includes all the
 *  GPUs on the node, and RDC_GROUP_EMPTY creates an empty group.
 *
 *  @param[in] group_name The group name specified as NULL terminated C String
 *
 *  @param[inout] p_rdc_group_id Caller provided pointer to rdc_gpu_group_t.
 *  Upon successful call, the value will contain the group id for following
 *  group API calls.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_gpu_create(rdc_handle_t p_rdc_handle,
    rdc_group_type_t type, const char* group_name,
    rdc_gpu_group_t* p_rdc_group_id);

/**
 *  @brief Add a GPU to the group
 *
 *  @details This method can add a GPU to the group
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] group_id The group id to which the GPU will be added.
 *
 *  @param[in] gpu_index The GPU index to be added to the group.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_gpu_add(rdc_handle_t p_rdc_handle,
    rdc_gpu_group_t group_id, uint32_t gpu_index);

/**
 *  @brief Get information about a GPU group
 *
 *  @details Get detail information about a GPU group created by
 *  rdc_group_gpu_create
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] p_rdc_group_id The GPU group handler created by
 *  rdc_group_gpu_create
 *
 *  @param[out] p_rdc_group_info The information of the GPU
 *  group p_rdc_group_id.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_gpu_get_info(rdc_handle_t p_rdc_handle,
            rdc_gpu_group_t p_rdc_group_id, rdc_group_info_t* p_rdc_group_info);

/**
 *  @brief Used to get information about all GPU groups in the system.
 *
 *  @details Get the list of GPU group ids in the system.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[out] group_id_list Array reference to fill GPU group
 *  ids in the system.
 *
 *  @param[out] count Number of GPU group returned in group_id_list.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_get_all_ids(rdc_handle_t p_rdc_handle,
            rdc_gpu_group_t group_id_list[], uint32_t* count);

/**
 *  @brief Destroy GPU group represented by p_rdc_group_id
 *
 *  @details Delete the logic group represented by p_rdc_group_id
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] p_rdc_group_id The group id
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_gpu_destroy(rdc_handle_t p_rdc_handle,
        rdc_gpu_group_t p_rdc_group_id);

/**
 *  @brief create a group of fields
 *
 *  @details The user can create a group of fields and perform an operation
 *  on a group of fields at once.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] num_field_ids Number of field IDs that are being provided
 *  in field_ids.
 *
 *  @param[in] field_ids Field IDs to be added to the newly-created
 *  field group.
 *
 *  @param[in] field_group_name Unique name for this group of fields.
 *
 *  @param[out] rdc_field_group_id Handle to the newly-created field group
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_field_create(rdc_handle_t p_rdc_handle,
            uint32_t num_field_ids, uint32_t* field_ids,
            const char* field_group_name, rdc_field_grp_t* rdc_field_group_id);

/**
 *  @brief Get information about a field group
 *
 *  @details Get detail information about a field group created by
 *  rdc_group_field_create
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] rdc_field_group_id The field group handler created by
 *  rdc_group_field_create
 *
 *  @param[out] field_group_info The information of the field group
 *  rdc_field_group_id.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_field_get_info(rdc_handle_t p_rdc_handle,
            rdc_field_grp_t rdc_field_group_id,
            rdc_field_group_info_t* field_group_info);

/**
 *  @brief Used to get information about all field groups in the system.
 *
 *  @details Get the list of field group ids in the system.
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[out] field_group_id_list Array reference to fill field group
 *  ids in the system.
 *
 *  @param[out] count Number of field group returned in field_group_id_list.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_field_get_all_ids(rdc_handle_t p_rdc_handle,
            rdc_field_grp_t field_group_id_list[], uint32_t* count);

/**
 *  @brief Destroy field group represented by rdc_field_group_id
 *
 *  @details Delete the logic group represented by rdc_field_group_id
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] rdc_field_group_id The field group id
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_group_field_destroy(rdc_handle_t p_rdc_handle,
        rdc_field_grp_t rdc_field_group_id);

/**
 *  @brief Request the RDC start recording updates for a given field
 *  collection.
 *
 *  @details Note that the first update of the field will not occur
 *  until the next field update cycle. To force a field update cycle,
 *  user must call rdc_field_update_all(1)
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] group_id The group of GPUs to be watched.
 *
 *  @param[in] field_group_id  The collection of fields to record
 *
 *  @param[in] update_freq  How often to update fields in usec.
 *
 *  @param[in] max_keep_age How long to keep data for fields in seconds.
 *
 *  @param[in] max_keep_samples Maximum number of samples to keep. 0=no limit.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_field_watch(rdc_handle_t p_rdc_handle,
        rdc_gpu_group_t group_id, rdc_field_grp_t field_group_id,
        uint64_t update_freq, double max_keep_age, uint32_t max_keep_samples);

/**
 *  @brief Request a latest cached field of a GPU
 *
 *  @details Note that the field can be cached after called rdc_field_watch
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] gpu_index The GPU index.
 *
 *  @param[in] field  The field id
 *
 *  @param[out] value  The field value got from cache.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_field_get_latest_value(rdc_handle_t p_rdc_handle,
        uint32_t gpu_index, uint32_t field, rdc_field_value* value);

/**
 *  @brief Request a history cached field of a GPU
 *
 *  @details Note that the field can be cached after called rdc_field_watch
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] gpu_index The GPU index.
 *
 *  @param[in] field  The field id
 *
 *  @param[in] since_time_stamp  Timestamp to request values since in
 *  usec since 1970.
 *
 *  @param[out] next_since_time_stamp Timestamp to use for sinceTimestamp
 *  on next call to this function
 *
 *  @param[out] value  The field value got from cache.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_field_get_value_since(rdc_handle_t p_rdc_handle,
        uint32_t gpu_index, uint32_t field, uint64_t since_time_stamp,
        uint64_t *next_since_time_stamp, rdc_field_value* value);

/**
 *  @brief Stop record updates for a given field collection.
 *
 *  @details The cache of those fields will not be updated after this call
 *
 *  @param[in] p_rdc_handle The RDC handler.
 *
 *  @param[in] group_id The GPU group id.
 *
 *  @param[in] field_group_id  The field group id.
 *
 *  @retval ::RDC_ST_OK is returned upon successful call.
 */
rdc_status_t rdc_field_unwatch(rdc_handle_t p_rdc_handle,
        rdc_gpu_group_t group_id, rdc_field_grp_t field_group_id);

/**
 *  @brief Get a description of a provided RDC error status
 *
 *  @details return the string in human readable format.
 *
 *  @param[in] status The RDC status.
 *
 *  @retval The string to describe the RDC status.
 */
const char* rdc_status_string(rdc_status_t status);

/**
 *  @brief Get the name of a field
 *
 *  @details return the string in human readable format.
 *
 *  @param[in] field_id The field id.
 *
 *  @retval The string to describe the field.
 */
const char* field_id_string(uint32_t field_id);

#ifdef __cplusplus
}
#endif  // __cplusplus

#endif  // INCLUDE_RDC_RDC_H_