/* SPDX-License-Identifier: BSD-3-Clause * Copyright(c) 2017 Intel Corporation */ #ifndef _RTE_SERVICE_H_ #define _RTE_SERVICE_H_ /** * @file * * Service functions * * The service functionality provided by this header allows a DPDK component * to indicate that it requires a function call in order for it to perform * its processing. * * An example usage of this functionality would be a component that registers * a service to perform a particular packet processing duty: for example the * eventdev software PMD. At startup the application requests all services * that have been registered, and the cores in the service-coremask run the * required services. The EAL removes these number of cores from the available * runtime cores, and dedicates them to performing service-core workloads. The * application has access to the remaining lcores as normal. */ #ifdef __cplusplus extern "C" { #endif #include #include #include #include #include #define RTE_SERVICE_NAME_MAX 32 /* Capabilities of a service. * * Use the *rte_service_probe_capability* function to check if a service is * capable of a specific capability. */ /** When set, the service is capable of having multiple threads run it at the * same time. */ #define RTE_SERVICE_CAP_MT_SAFE (1 << 0) /** * Return the number of services registered. * * The number of services registered can be passed to *rte_service_get_by_id*, * enabling the application to retrieve the specification of each service. * * @return The number of services registered. */ uint32_t rte_service_get_count(void); /** * Return the id of a service by name. * * This function provides the id of the service using the service name as * lookup key. The service id is to be passed to other functions in the * rte_service_* API. * * Example usage: * @code * uint32_t service_id; * int32_t ret = rte_service_get_by_name("service_X", &service_id); * if (ret) { * // handle error * } * @endcode * * @param name The name of the service to retrieve * @param[out] service_id A pointer to a uint32_t, to be filled in with the id. * @retval 0 Success. The service id is provided in *service_id*. * @retval -EINVAL Null *service_id* pointer provided * @retval -ENODEV No such service registered */ int32_t rte_service_get_by_name(const char *name, uint32_t *service_id); /** * Return the name of the service. * * @return A pointer to the name of the service. The returned pointer remains * in ownership of the service, and the application must not free it. */ const char *rte_service_get_name(uint32_t id); /** * Check if a service has a specific capability. * * This function returns if *service* has implements *capability*. * See RTE_SERVICE_CAP_* defines for a list of valid capabilities. * @retval 1 Capability supported by this service instance * @retval 0 Capability not supported by this service instance */ int32_t rte_service_probe_capability(uint32_t id, uint32_t capability); /** * Map or unmap a lcore to a service. * * Each core can be added or removed from running a specific service. This * function enables or disables *lcore* to run *service_id*. * * If multiple cores are enabled on a service, an atomic is used to ensure that * only one cores runs the service at a time. The exception to this is when * a service indicates that it is multi-thread safe by setting the capability * called RTE_SERVICE_CAP_MT_SAFE. With the multi-thread safe capability set, * the service function can be run on multiple threads at the same time. * * @param service_id the service to apply the lcore to * @param lcore The lcore that will be mapped to service * @param enable Zero to unmap or disable the core, non-zero to enable * * @retval 0 lcore map updated successfully * @retval -EINVAL An invalid service or lcore was provided. */ int32_t rte_service_map_lcore_set(uint32_t service_id, uint32_t lcore, uint32_t enable); /** * Retrieve the mapping of an lcore to a service. * * @param service_id the service to apply the lcore to * @param lcore The lcore that will be mapped to service * * @retval 1 lcore is mapped to service * @retval 0 lcore is not mapped to service * @retval -EINVAL An invalid service or lcore was provided. */ int32_t rte_service_map_lcore_get(uint32_t service_id, uint32_t lcore); /** * Set the runstate of the service. * * Each service is either running or stopped. Setting a non-zero runstate * enables the service to run, while setting runstate zero disables it. * * @param id The id of the service * @param runstate The run state to apply to the service * * @retval 0 The service was successfully started * @retval -EINVAL Invalid service id */ int32_t rte_service_runstate_set(uint32_t id, uint32_t runstate); /** * Get the runstate for the service with *id*. See *rte_service_runstate_set* * for details of runstates. A service can call this function to ensure that * the application has indicated that it will receive CPU cycles. Either a * service-core is mapped (default case), or the application has explicitly * disabled the check that a service-cores is mapped to the service and takes * responsibility to run the service manually using the available function * *rte_service_run_iter_on_app_lcore* to do so. * * @retval 1 Service is running * @retval 0 Service is stopped * @retval -EINVAL Invalid service id */ int32_t rte_service_runstate_get(uint32_t id); /** * @warning * @b EXPERIMENTAL: this API may change, or be removed, without prior notice * * This function returns whether the service may be currently executing on * at least one lcore, or definitely is not. This function can be used to * determine if, after setting the service runstate to stopped, the service * is still executing a service lcore. * * Care must be taken if calling this function when the service runstate is * running, since the result of this function may be incorrect by the time the * function returns due to service cores running in parallel. * * @retval 1 Service may be running on one or more lcores * @retval 0 Service is not running on any lcore * @retval -EINVAL Invalid service id */ int32_t __rte_experimental rte_service_may_be_active(uint32_t id); /** * Enable or disable the check for a service-core being mapped to the service. * An application can disable the check when takes the responsibility to run a * service itself using *rte_service_run_iter_on_app_lcore*. * * @param id The id of the service to set the check on * @param enable When zero, the check is disabled. Non-zero enables the check. * * @retval 0 Success * @retval -EINVAL Invalid service ID */ int32_t rte_service_set_runstate_mapped_check(uint32_t id, int32_t enable); /** * This function runs a service callback from a non-service lcore. * * This function is designed to enable gradual porting to service cores, and * to enable unit tests to verify a service behaves as expected. * * When called, this function ensures that the service identified by *id* is * safe to run on this lcore. Multi-thread safe services are invoked even if * other cores are simultaneously running them as they are multi-thread safe. * * Multi-thread unsafe services are handled depending on the variable * *serialize_multithread_unsafe*: * - When set, the function will check if a service is already being invoked * on another lcore, refusing to run it and returning -EBUSY. * - When zero, the application takes responsibility to ensure that the service * indicated by *id* is not going to be invoked by another lcore. This setting * avoids atomic operations, so is likely to be more performant. * * @param id The ID of the service to run * @param serialize_multithread_unsafe This parameter indicates to the service * cores library if it is required to use atomics to serialize access * to mult-thread unsafe services. As there is an overhead in using * atomics, applications can choose to enable or disable this feature * * Note that any thread calling this function MUST be a DPDK EAL thread, as * the *rte_lcore_id* function is used to access internal data structures. * * @retval 0 Service was run on the calling thread successfully * @retval -EBUSY Another lcore is executing the service, and it is not a * multi-thread safe service, so the service was not run on this lcore * @retval -ENOEXEC Service is not in a run-able state * @retval -EINVAL Invalid service id */ int32_t rte_service_run_iter_on_app_lcore(uint32_t id, uint32_t serialize_multithread_unsafe); /** * Start a service core. * * Starting a core makes the core begin polling. Any services assigned to it * will be run as fast as possible. The application must ensure that the lcore * is in a launchable state: e.g. call *rte_eal_lcore_wait* on the lcore_id * before calling this function. * * @retval 0 Success * @retval -EINVAL Failed to start core. The *lcore_id* passed in is not * currently assigned to be a service core. */ int32_t rte_service_lcore_start(uint32_t lcore_id); /** * Stop a service core. * * Stopping a core makes the core become idle, but remains assigned as a * service core. * * @retval 0 Success * @retval -EINVAL Invalid *lcore_id* provided * @retval -EALREADY Already stopped core * @retval -EBUSY Failed to stop core, as it would cause a service to not * be run, as this is the only core currently running the service. * The application must stop the service first, and then stop the * lcore. */ int32_t rte_service_lcore_stop(uint32_t lcore_id); /** * Adds lcore to the list of service cores. * * This functions can be used at runtime in order to modify the service core * mask. * * @retval 0 Success * @retval -EBUSY lcore is busy, and not available for service core duty * @retval -EALREADY lcore is already added to the service core list * @retval -EINVAL Invalid lcore provided */ int32_t rte_service_lcore_add(uint32_t lcore); /** * Removes lcore from the list of service cores. * * This can fail if the core is not stopped, see *rte_service_core_stop*. * * @retval 0 Success * @retval -EBUSY Lcore is not stopped, stop service core before removing. * @retval -EINVAL failed to add lcore to service core mask. */ int32_t rte_service_lcore_del(uint32_t lcore); /** * Retrieve the number of service cores currently available. * * This function returns the integer count of service cores available. The * service core count can be used in mapping logic when creating mappings * from service cores to services. * * See *rte_service_lcore_list* for details on retrieving the lcore_id of each * service core. * * @return The number of service cores currently configured. */ int32_t rte_service_lcore_count(void); /** * Resets all service core mappings. This does not remove the service cores * from duty, just unmaps all services / cores, and stops() the service cores. * The runstate of services is not modified. * * @retval 0 Success */ int32_t rte_service_lcore_reset_all(void); /** * Enable or disable statistics collection for *service*. * * This function enables per core, per-service cycle count collection. * @param id The service to enable statistics gathering on. * @param enable Zero to disable statistics, non-zero to enable. * @retval 0 Success * @retval -EINVAL Invalid service pointer passed */ int32_t rte_service_set_stats_enable(uint32_t id, int32_t enable); /** * Retrieve the list of currently enabled service cores. * * This function fills in an application supplied array, with each element * indicating the lcore_id of a service core. * * Adding and removing service cores can be performed using * *rte_service_lcore_add* and *rte_service_lcore_del*. * @param [out] array An array of at least *rte_service_lcore_count* items. * If statically allocating the buffer, use RTE_MAX_LCORE. * @param [out] n The size of *array*. * @retval >=0 Number of service cores that have been populated in the array * @retval -ENOMEM The provided array is not large enough to fill in the * service core list. No items have been populated, call this function * with a size of at least *rte_service_core_count* items. */ int32_t rte_service_lcore_list(uint32_t array[], uint32_t n); /** * Get the number of services running on the supplied lcore. * * @param lcore Id of the service core. * @retval >=0 Number of services registered to this core. * @retval -EINVAL Invalid lcore provided * @retval -ENOTSUP The provided lcore is not a service core. */ int32_t rte_service_lcore_count_services(uint32_t lcore); /** * Dumps any information available about the service. When id is UINT32_MAX, * this function dumps info for all services. * * @retval 0 Statistics have been successfully dumped * @retval -EINVAL Invalid service id provided */ int32_t rte_service_dump(FILE *f, uint32_t id); /** * Returns the number of cycles that this service has consumed */ #define RTE_SERVICE_ATTR_CYCLES 0 /** * Returns the count of invocations of this service function */ #define RTE_SERVICE_ATTR_CALL_COUNT 1 /** * Get an attribute from a service. * * @retval 0 Success, the attribute value has been written to *attr_value*. * -EINVAL Invalid id, attr_id or attr_value was NULL. */ int32_t rte_service_attr_get(uint32_t id, uint32_t attr_id, uint32_t *attr_value); /** * Reset all attribute values of a service. * * @param id The service to reset all statistics of * @retval 0 Successfully reset attributes * -EINVAL Invalid service id provided */ int32_t rte_service_attr_reset_all(uint32_t id); /** * Returns the number of times the service runner has looped. */ #define RTE_SERVICE_LCORE_ATTR_LOOPS 0 /** * @warning * @b EXPERIMENTAL: this API may change without prior notice * * Get an attribute from a service core. * * @param lcore Id of the service core. * @param attr_id Id of the attribute to be retrieved. * @param [out] attr_value Pointer to storage in which to write retrieved value. * @retval 0 Success, the attribute value has been written to *attr_value*. * -EINVAL Invalid lcore, attr_id or attr_value was NULL. * -ENOTSUP lcore is not a service core. */ int32_t __rte_experimental rte_service_lcore_attr_get(uint32_t lcore, uint32_t attr_id, uint64_t *attr_value); /** * @warning * @b EXPERIMENTAL: this API may change without prior notice * * Reset all attribute values of a service core. * * @param lcore The service core to reset all the statistics of * @retval 0 Successfully reset attributes * -EINVAL Invalid service id provided * -ENOTSUP lcore is not a service core. */ int32_t __rte_experimental rte_service_lcore_attr_reset_all(uint32_t lcore); #ifdef __cplusplus } #endif #endif /* _RTE_SERVICE_H_ */