os_allocation.h

/*
 * BSD LICENSE
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/**
 * @brief Internal header file to PQoS OS allocation module
 */

#ifndef __PQOS_OS_ALLOC_H__
#define __PQOS_OS_ALLOC_H__

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief Initializes resctrl file system used for OS allocation interface
 *
 * @param cpu cpu topology structure
 * @param cap capabilities structure
 *
 * @return Operational status
 * @retval PQOS_RETVAL_OK success
 */
int os_alloc_init(const struct pqos_cpuinfo *cpu, const struct pqos_cap *cap);

/**
 * @brief Shuts down allocation sub-module for OS allocation
 *
 * @return Operation status
 * @retval PQOS_RETVAL_OK success
 */
int os_alloc_fini(void);

/**
 * @brief OS interface to assign first available
 *        COS to cores in \a core_array
 *
 * While searching for available COS take technologies it is intended to use
 * with into account.
 * Note on \a technology and \a core_array selection:
 * - if L2 CAT technology is requested then cores need to belong to
 *   one L2 cluster (same L2ID)
 * - if only L3 CAT is requested then cores need to belong to one socket
 *
 * @param [in] technology bit mask selecting technologies
 *             (1 << enum pqos_cap_type)
 * @param [in] core_array list of core ids
 * @param [in] core_num number of core ids in the \a core_array
 * @param [out] class_id place to store reserved COS id
 *
 * @return Operations status
 */
int os_alloc_assign(const unsigned technology,
                    const unsigned *core_array,
                    const unsigned core_num,
                    unsigned *class_id);

/**
 * @brief OS interface to reassign cores
 *        in \a core_array to default COS#0
 *
 * @param [in] core_array list of core ids
 * @param [in] core_num number of core ids in the \a core_array
 *
 * @return Operations status
 */
int os_alloc_release(const unsigned *core_array, const unsigned core_num);

/**
 * @brief Assign first available COS to tasks in \a task_array
 *        Searches all COS directories from highest to lowest
 *
 * While searching for available COS take technologies it is intended to use
 * with into account.
 * Note on \a technology parameter:
 * - this parameter is currently reserved for future use
 * - resctrl (Linux interface) will only provide the highest class id common
 *   to all supported technologies
 *
 * @param [in] technology bit mask selecting technologies
 *             (1 << enum pqos_cap_type)
 * @param [in] task_array list of task ids
 * @param [in] task_num number of task ids in the \a task_array
 * @param [out] class_id place to store reserved COS id
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_alloc_assign_pid(const unsigned technology,
                        const pid_t *task_array,
                        const unsigned task_num,
                        unsigned *class_id);

/**
 * @brief Reassign tasks in \a task_array to default COS#0
 *
 * @param [in] task_array list of task ids
 * @param [in] task_num number of task ids in the \a task_array
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_alloc_release_pid(const pid_t *task_array, const unsigned task_num);

/**
 * @brief OS interface to reset configuration of allocation technologies
 *
 * Reverts allocation state to the one after reset:
 * - all cores associated with COS0
 *
 * As part of allocation reset CDP reconfiguration can be performed.
 * This can be requested via \a l3_cdp_cfg or \a l2_cdp_cfg.
 *
 * As part of allocation reset MBA reconfiguration can be performed.
 * This can be requested via \a mba_cfg.
 *
 * @param [in] l3_cdp_cfg requested L3 CAT CDP config
 * @param [in] l2_cdp_cfg requested L2 CAT CDP config
 * @param [in] mba_cfg requested MBA config
 *
 * @return Operation status
 * @retval PQOS_RETVAL_OK on success
 */
int os_alloc_reset(const enum pqos_cdp_config l3_cdp_cfg,
                   const enum pqos_cdp_config l2_cdp_cfg,
                   const enum pqos_mba_config mba_cfg);

/**
 * @brief OS interface to set classes of service
 *        defined by \a ca on \a l3cat_id
 *
 * @param [in] l3cat_id L3 CAT resource id
 * @param [in] num_cos number of classes of service at \a ca
 * @param [in] ca table with class of service definitions
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_l3ca_set(const unsigned l3cat_id,
                const unsigned num_cos,
                const struct pqos_l3ca *ca);

/**
 * @brief OS interface to read classes of service from \a l3cat_id
 *
 * @param [in] l3cat_id L3 CAT resource id
 * @param [in] max_num_ca maximum number of classes of service
 *             that can be accommodated at \a ca
 * @param [out] num_ca number of classes of service read into \a ca
 * @param [out] ca table with read classes of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_l3ca_get(const unsigned l3cat_id,
                const unsigned max_num_ca,
                unsigned *num_ca,
                struct pqos_l3ca *ca);

/**
 * @brief Check minimum cbm bits accepted by OS interface for L3 CAT
 *
 * @param [out] min_cbm_bits minimum number of bits that must be set
 *
 * @return Operational status
 * @retval PQOS_RETVAL_OK on success
 */
int os_l3ca_get_min_cbm_bits(unsigned *min_cbm_bits);

/**
 * @brief OS interface to set classes of
 *        service defined by \a ca on \a l2id
 *
 * @param [in] l2id unique L2 cache identifier
 * @param [in] num_cos number of classes of service at \a ca
 * @param [in] ca table with class of service definitions
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_l2ca_set(const unsigned l2id,
                const unsigned num_cos,
                const struct pqos_l2ca *ca);

/**
 * @brief OS interface to read classes of service from \a l2id
 *
 * @param [in] l2id unique L2 cache identifier
 * @param [in] max_num_ca maximum number of classes of service
 *             that can be accommodated at \a ca
 * @param [out] num_ca number of classes of service read into \a ca
 * @param [out] ca table with read classes of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_l2ca_get(const unsigned l2id,
                const unsigned max_num_ca,
                unsigned *num_ca,
                struct pqos_l2ca *ca);

/**
 * @brief Check minimum cbm bits accepted by OS interface for L2 CAT
 *
 * @param [out] min_cbm_bits minimum number of bits that must be set
 *
 * @return Operational status
 * @retval PQOS_RETVAL_OK on success
 */
int os_l2ca_get_min_cbm_bits(unsigned *min_cbm_bits);

/**
 * @brief OS interface to set classes of service
 *        defined by \a mba_id
 *
 * @param [in]  mba_id MBA resource id
 * @param [in]  num_cos number of classes of service at \a ca
 * @param [in]  requested table with class of service definitions
 * @param [out] actual table with class of service definitions
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_mba_set(const unsigned mba_id,
               const unsigned num_cos,
               const struct pqos_mba *requested,
               struct pqos_mba *actual);

/**
 * @brief OS interface to set classes of service defined by \a mba_id
 * @NOTE: This function is specific to AMD
 *
 * @param [in]  mba_id MBA resource id
 * @param [in]  num_cos number of classes of service at \a ca
 * @param [in]  requested table with class of service definitions
 * @param [out] actual table with class of service definitions
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_mba_set_amd(const unsigned mba_id,
                   const unsigned num_cos,
                   const struct pqos_mba *requested,
                   struct pqos_mba *actual);

/**
 * @brief OS interface to read MBA from \a mba_id
 *
 * @param [in]  mba_id MBA resource id
 * @param [in]  max_num_cos maximum number of classes of service
 *              that can be accommodated at \a mba_tab
 * @param [out] num_cos number of classes of service read into \a mba_tab
 * @param [out] mba_tab table with read classes of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_mba_get(const unsigned mba_id,
               const unsigned max_num_cos,
               unsigned *num_cos,
               struct pqos_mba *mba_tab);

/**
 * @brief OS interface to read MBA from \a mba_id
 * @NOTE: This function is specific to AMD
 *
 * @param [in]  mba_id MBA resource id
 * @param [in]  max_num_cos maximum number of classes of service
 *              that can be accommodated at \a mba_tab
 * @param [out] num_cos number of classes of service read into \a mba_tab
 * @param [out] mba_tab table with read classes of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_mba_get_amd(const unsigned mba_id,
                   const unsigned max_num_cos,
                   unsigned *num_cos,
                   struct pqos_mba *mba_tab);

/**
 * @brief OS interface to associate \a lcore
 *        with given class of service
 *
 * @param [in] lcore CPU logical core id
 * @param [in] class_id class of service
 *
 * @return Operations status
 */
int os_alloc_assoc_set(const unsigned lcore, const unsigned class_id);

/**
 * @brief OS interface to read association
 *        of \a lcore with class of service
 *
 * @param [in] lcore CPU logical core id
 * @param [out] class_id class of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_alloc_assoc_get(const unsigned lcore, unsigned *class_id);

/**
 * @brief Retrieves task id's from resctrl task file for a given COS
 *
 * @param [in] class_id Class of Service ID
 * @param [out] count place to store actual number of task id's returned
 *
 * @return Allocated task id array
 * @retval NULL on error
 */
unsigned *os_pid_get_pid_assoc(const unsigned class_id, unsigned *count);

/**
 * @brief OS interface to associate \a task
 *        with given class of service
 *
 * @param [in] task task id to be associated
 * @param [in] class_id class of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_alloc_assoc_set_pid(const pid_t task, const unsigned class_id);

/**
 * @brief OS interface to read association
 *        of \a task with class of service
 *
 * @param [in] task task id to find association
 * @param [out] class_id class of service
 *
 * @return Operations status
 * @retval PQOS_RETVAL_OK on success
 */
int os_alloc_assoc_get_pid(const pid_t task, unsigned *class_id);

#ifdef __cplusplus
}
#endif

#endif /* __PQOS_OS_ALLOC_H__ */