1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2017 Intel Corporation
5 #ifndef _RTE_SERVICE_H_
6 #define _RTE_SERVICE_H_
13 * The service functionality provided by this header allows a DPDK component
14 * to indicate that it requires a function call in order for it to perform
17 * An example usage of this functionality would be a component that registers
18 * a service to perform a particular packet processing duty: for example the
19 * eventdev software PMD. At startup the application requests all services
20 * that have been registered, and the cores in the service-coremask run the
21 * required services. The EAL removes these number of cores from the available
22 * runtime cores, and dedicates them to performing service-core workloads. The
23 * application has access to the remaining lcores as normal.
32 #include <sys/queue.h>
34 #include <rte_lcore.h>
36 #define RTE_SERVICE_NAME_MAX 32
38 /* Capabilities of a service.
40 * Use the *rte_service_probe_capability* function to check if a service is
41 * capable of a specific capability.
43 /** When set, the service is capable of having multiple threads run it at the
46 #define RTE_SERVICE_CAP_MT_SAFE (1 << 0)
50 * @b EXPERIMENTAL: this API may change without prior notice
52 * Return the number of services registered.
54 * The number of services registered can be passed to *rte_service_get_by_id*,
55 * enabling the application to retrieve the specification of each service.
57 * @return The number of services registered.
59 uint32_t rte_service_get_count(void);
63 * @b EXPERIMENTAL: this API may change without prior notice
65 * Return the id of a service by name.
67 * This function provides the id of the service using the service name as
68 * lookup key. The service id is to be passed to other functions in the
73 * uint32_t service_id;
74 * int32_t ret = rte_service_get_by_name("service_X", &service_id);
80 * @param name The name of the service to retrieve
81 * @param[out] service_id A pointer to a uint32_t, to be filled in with the id.
82 * @retval 0 Success. The service id is provided in *service_id*.
83 * @retval -EINVAL Null *service_id* pointer provided
84 * @retval -ENODEV No such service registered
86 int32_t rte_service_get_by_name(const char *name, uint32_t *service_id);
90 * @b EXPERIMENTAL: this API may change without prior notice
92 * Return the name of the service.
94 * @return A pointer to the name of the service. The returned pointer remains
95 * in ownership of the service, and the application must not free it.
97 const char *rte_service_get_name(uint32_t id);
101 * @b EXPERIMENTAL: this API may change without prior notice
103 * Check if a service has a specific capability.
105 * This function returns if *service* has implements *capability*.
106 * See RTE_SERVICE_CAP_* defines for a list of valid capabilities.
107 * @retval 1 Capability supported by this service instance
108 * @retval 0 Capability not supported by this service instance
110 int32_t rte_service_probe_capability(uint32_t id, uint32_t capability);
114 * @b EXPERIMENTAL: this API may change without prior notice
116 * Map or unmap a lcore to a service.
118 * Each core can be added or removed from running a specific service. This
119 * function enables or disables *lcore* to run *service_id*.
121 * If multiple cores are enabled on a service, an atomic is used to ensure that
122 * only one cores runs the service at a time. The exception to this is when
123 * a service indicates that it is multi-thread safe by setting the capability
124 * called RTE_SERVICE_CAP_MT_SAFE. With the multi-thread safe capability set,
125 * the service function can be run on multiple threads at the same time.
127 * @param service_id the service to apply the lcore to
128 * @param lcore The lcore that will be mapped to service
129 * @param enable Zero to unmap or disable the core, non-zero to enable
131 * @retval 0 lcore map updated successfully
132 * @retval -EINVAL An invalid service or lcore was provided.
134 int32_t rte_service_map_lcore_set(uint32_t service_id, uint32_t lcore,
139 * @b EXPERIMENTAL: this API may change without prior notice
141 * Retrieve the mapping of an lcore to a service.
143 * @param service_id the service to apply the lcore to
144 * @param lcore The lcore that will be mapped to service
146 * @retval 1 lcore is mapped to service
147 * @retval 0 lcore is not mapped to service
148 * @retval -EINVAL An invalid service or lcore was provided.
150 int32_t rte_service_map_lcore_get(uint32_t service_id, uint32_t lcore);
154 * @b EXPERIMENTAL: this API may change without prior notice
156 * Set the runstate of the service.
158 * Each service is either running or stopped. Setting a non-zero runstate
159 * enables the service to run, while setting runstate zero disables it.
161 * @param id The id of the service
162 * @param runstate The run state to apply to the service
164 * @retval 0 The service was successfully started
165 * @retval -EINVAL Invalid service id
167 int32_t rte_service_runstate_set(uint32_t id, uint32_t runstate);
171 * @b EXPERIMENTAL: this API may change without prior notice
173 * Get the runstate for the service with *id*. See *rte_service_runstate_set*
174 * for details of runstates. A service can call this function to ensure that
175 * the application has indicated that it will receive CPU cycles. Either a
176 * service-core is mapped (default case), or the application has explicitly
177 * disabled the check that a service-cores is mapped to the service and takes
178 * responsibility to run the service manually using the available function
179 * *rte_service_run_iter_on_app_lcore* to do so.
181 * @retval 1 Service is running
182 * @retval 0 Service is stopped
183 * @retval -EINVAL Invalid service id
185 int32_t rte_service_runstate_get(uint32_t id);
189 * @b EXPERIMENTAL: this API may change without prior notice
191 * Enable or disable the check for a service-core being mapped to the service.
192 * An application can disable the check when takes the responsibility to run a
193 * service itself using *rte_service_run_iter_on_app_lcore*.
195 * @param id The id of the service to set the check on
196 * @param enable When zero, the check is disabled. Non-zero enables the check.
199 * @retval -EINVAL Invalid service ID
201 int32_t rte_service_set_runstate_mapped_check(uint32_t id, int32_t enable);
205 * @b EXPERIMENTAL: this API may change without prior notice
207 * This function runs a service callback from a non-service lcore.
209 * This function is designed to enable gradual porting to service cores, and
210 * to enable unit tests to verify a service behaves as expected.
212 * When called, this function ensures that the service identified by *id* is
213 * safe to run on this lcore. Multi-thread safe services are invoked even if
214 * other cores are simultaneously running them as they are multi-thread safe.
216 * Multi-thread unsafe services are handled depending on the variable
217 * *serialize_multithread_unsafe*:
218 * - When set, the function will check if a service is already being invoked
219 * on another lcore, refusing to run it and returning -EBUSY.
220 * - When zero, the application takes responsibility to ensure that the service
221 * indicated by *id* is not going to be invoked by another lcore. This setting
222 * avoids atomic operations, so is likely to be more performant.
224 * @param id The ID of the service to run
225 * @param serialize_multithread_unsafe This parameter indicates to the service
226 * cores library if it is required to use atomics to serialize access
227 * to mult-thread unsafe services. As there is an overhead in using
228 * atomics, applications can choose to enable or disable this feature
230 * Note that any thread calling this function MUST be a DPDK EAL thread, as
231 * the *rte_lcore_id* function is used to access internal data structures.
233 * @retval 0 Service was run on the calling thread successfully
234 * @retval -EBUSY Another lcore is executing the service, and it is not a
235 * multi-thread safe service, so the service was not run on this lcore
236 * @retval -ENOEXEC Service is not in a run-able state
237 * @retval -EINVAL Invalid service id
239 int32_t rte_service_run_iter_on_app_lcore(uint32_t id,
240 uint32_t serialize_multithread_unsafe);
244 * @b EXPERIMENTAL: this API may change without prior notice
246 * Start a service core.
248 * Starting a core makes the core begin polling. Any services assigned to it
249 * will be run as fast as possible. The application must ensure that the lcore
250 * is in a launchable state: e.g. call *rte_eal_lcore_wait* on the lcore_id
251 * before calling this function.
254 * @retval -EINVAL Failed to start core. The *lcore_id* passed in is not
255 * currently assigned to be a service core.
257 int32_t rte_service_lcore_start(uint32_t lcore_id);
261 * @b EXPERIMENTAL: this API may change without prior notice
263 * Stop a service core.
265 * Stopping a core makes the core become idle, but remains assigned as a
269 * @retval -EINVAL Invalid *lcore_id* provided
270 * @retval -EALREADY Already stopped core
271 * @retval -EBUSY Failed to stop core, as it would cause a service to not
272 * be run, as this is the only core currently running the service.
273 * The application must stop the service first, and then stop the
276 int32_t rte_service_lcore_stop(uint32_t lcore_id);
280 * @b EXPERIMENTAL: this API may change without prior notice
282 * Adds lcore to the list of service cores.
284 * This functions can be used at runtime in order to modify the service core
288 * @retval -EBUSY lcore is busy, and not available for service core duty
289 * @retval -EALREADY lcore is already added to the service core list
290 * @retval -EINVAL Invalid lcore provided
292 int32_t rte_service_lcore_add(uint32_t lcore);
296 * @b EXPERIMENTAL: this API may change without prior notice
298 * Removes lcore from the list of service cores.
300 * This can fail if the core is not stopped, see *rte_service_core_stop*.
303 * @retval -EBUSY Lcore is not stopped, stop service core before removing.
304 * @retval -EINVAL failed to add lcore to service core mask.
306 int32_t rte_service_lcore_del(uint32_t lcore);
310 * @b EXPERIMENTAL: this API may change without prior notice
312 * Retrieve the number of service cores currently available.
314 * This function returns the integer count of service cores available. The
315 * service core count can be used in mapping logic when creating mappings
316 * from service cores to services.
318 * See *rte_service_lcore_list* for details on retrieving the lcore_id of each
321 * @return The number of service cores currently configured.
323 int32_t rte_service_lcore_count(void);
327 * @b EXPERIMENTAL: this API may change without prior notice
329 * Resets all service core mappings. This does not remove the service cores
330 * from duty, just unmaps all services / cores, and stops() the service cores.
331 * The runstate of services is not modified.
335 int32_t rte_service_lcore_reset_all(void);
339 * @b EXPERIMENTAL: this API may change without prior notice
341 * Enable or disable statistics collection for *service*.
343 * This function enables per core, per-service cycle count collection.
344 * @param id The service to enable statistics gathering on.
345 * @param enable Zero to disable statistics, non-zero to enable.
347 * @retval -EINVAL Invalid service pointer passed
349 int32_t rte_service_set_stats_enable(uint32_t id, int32_t enable);
353 * @b EXPERIMENTAL: this API may change without prior notice
355 * Retrieve the list of currently enabled service cores.
357 * This function fills in an application supplied array, with each element
358 * indicating the lcore_id of a service core.
360 * Adding and removing service cores can be performed using
361 * *rte_service_lcore_add* and *rte_service_lcore_del*.
362 * @param [out] array An array of at least *rte_service_lcore_count* items.
363 * If statically allocating the buffer, use RTE_MAX_LCORE.
364 * @param [out] n The size of *array*.
365 * @retval >=0 Number of service cores that have been populated in the array
366 * @retval -ENOMEM The provided array is not large enough to fill in the
367 * service core list. No items have been populated, call this function
368 * with a size of at least *rte_service_core_count* items.
370 int32_t rte_service_lcore_list(uint32_t array[], uint32_t n);
374 * @b EXPERIMENTAL: this API may change without prior notice
376 * Get the numer of services running on the supplied lcore.
378 * @param lcore Id of the service core.
379 * @retval >=0 Number of services registered to this core.
380 * @retval -EINVAL Invalid lcore provided
381 * @retval -ENOTSUP The provided lcore is not a service core.
383 int32_t rte_service_lcore_count_services(uint32_t lcore);
387 * @b EXPERIMENTAL: this API may change without prior notice
389 * Dumps any information available about the service. When id is UINT32_MAX,
390 * this function dumps info for all services.
392 * @retval 0 Statistics have been successfully dumped
393 * @retval -EINVAL Invalid service id provided
395 int32_t rte_service_dump(FILE *f, uint32_t id);
398 * Returns the number of cycles that this service has consumed
400 #define RTE_SERVICE_ATTR_CYCLES 0
404 * @b EXPERIMENTAL: this API may change without prior notice
406 * Get an attribute from a service.
408 * @retval 0 Success, the attribute value has been written to *attr_value*.
409 * -EINVAL Invalid id, attr_id or attr_value was NULL.
411 int32_t rte_service_attr_get(uint32_t id, uint32_t attr_id,
412 uint32_t *attr_value);
419 #endif /* _RTE_SERVICE_H_ */