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_config.h>
35 #include <rte_lcore.h>
37 #define RTE_SERVICE_NAME_MAX 32
39 /* Capabilities of a service.
41 * Use the *rte_service_probe_capability* function to check if a service is
42 * capable of a specific capability.
44 /** When set, the service is capable of having multiple threads run it at the
47 #define RTE_SERVICE_CAP_MT_SAFE (1 << 0)
51 * @b EXPERIMENTAL: this API may change without prior notice
53 * Return the number of services registered.
55 * The number of services registered can be passed to *rte_service_get_by_id*,
56 * enabling the application to retrieve the specification of each service.
58 * @return The number of services registered.
60 uint32_t __rte_experimental rte_service_get_count(void);
64 * @b EXPERIMENTAL: this API may change without prior notice
66 * Return the id of a service by name.
68 * This function provides the id of the service using the service name as
69 * lookup key. The service id is to be passed to other functions in the
74 * uint32_t service_id;
75 * int32_t ret = rte_service_get_by_name("service_X", &service_id);
81 * @param name The name of the service to retrieve
82 * @param[out] service_id A pointer to a uint32_t, to be filled in with the id.
83 * @retval 0 Success. The service id is provided in *service_id*.
84 * @retval -EINVAL Null *service_id* pointer provided
85 * @retval -ENODEV No such service registered
87 int32_t __rte_experimental rte_service_get_by_name(const char *name,
88 uint32_t *service_id);
92 * @b EXPERIMENTAL: this API may change without prior notice
94 * Return the name of the service.
96 * @return A pointer to the name of the service. The returned pointer remains
97 * in ownership of the service, and the application must not free it.
99 const char __rte_experimental *rte_service_get_name(uint32_t id);
103 * @b EXPERIMENTAL: this API may change without prior notice
105 * Check if a service has a specific capability.
107 * This function returns if *service* has implements *capability*.
108 * See RTE_SERVICE_CAP_* defines for a list of valid capabilities.
109 * @retval 1 Capability supported by this service instance
110 * @retval 0 Capability not supported by this service instance
112 int32_t __rte_experimental rte_service_probe_capability(uint32_t id,
113 uint32_t capability);
117 * @b EXPERIMENTAL: this API may change without prior notice
119 * Map or unmap a lcore to a service.
121 * Each core can be added or removed from running a specific service. This
122 * function enables or disables *lcore* to run *service_id*.
124 * If multiple cores are enabled on a service, an atomic is used to ensure that
125 * only one cores runs the service at a time. The exception to this is when
126 * a service indicates that it is multi-thread safe by setting the capability
127 * called RTE_SERVICE_CAP_MT_SAFE. With the multi-thread safe capability set,
128 * the service function can be run on multiple threads at the same time.
130 * @param service_id the service to apply the lcore to
131 * @param lcore The lcore that will be mapped to service
132 * @param enable Zero to unmap or disable the core, non-zero to enable
134 * @retval 0 lcore map updated successfully
135 * @retval -EINVAL An invalid service or lcore was provided.
137 int32_t __rte_experimental rte_service_map_lcore_set(uint32_t service_id,
138 uint32_t lcore, uint32_t enable);
142 * @b EXPERIMENTAL: this API may change without prior notice
144 * Retrieve the mapping of an lcore to a service.
146 * @param service_id the service to apply the lcore to
147 * @param lcore The lcore that will be mapped to service
149 * @retval 1 lcore is mapped to service
150 * @retval 0 lcore is not mapped to service
151 * @retval -EINVAL An invalid service or lcore was provided.
153 int32_t __rte_experimental rte_service_map_lcore_get(uint32_t service_id,
158 * @b EXPERIMENTAL: this API may change without prior notice
160 * Set the runstate of the service.
162 * Each service is either running or stopped. Setting a non-zero runstate
163 * enables the service to run, while setting runstate zero disables it.
165 * @param id The id of the service
166 * @param runstate The run state to apply to the service
168 * @retval 0 The service was successfully started
169 * @retval -EINVAL Invalid service id
171 int32_t __rte_experimental rte_service_runstate_set(uint32_t id, uint32_t runstate);
175 * @b EXPERIMENTAL: this API may change without prior notice
177 * Get the runstate for the service with *id*. See *rte_service_runstate_set*
178 * for details of runstates. A service can call this function to ensure that
179 * the application has indicated that it will receive CPU cycles. Either a
180 * service-core is mapped (default case), or the application has explicitly
181 * disabled the check that a service-cores is mapped to the service and takes
182 * responsibility to run the service manually using the available function
183 * *rte_service_run_iter_on_app_lcore* to do so.
185 * @retval 1 Service is running
186 * @retval 0 Service is stopped
187 * @retval -EINVAL Invalid service id
189 int32_t __rte_experimental rte_service_runstate_get(uint32_t id);
193 * @b EXPERIMENTAL: this API may change without prior notice
195 * Enable or disable the check for a service-core being mapped to the service.
196 * An application can disable the check when takes the responsibility to run a
197 * service itself using *rte_service_run_iter_on_app_lcore*.
199 * @param id The id of the service to set the check on
200 * @param enable When zero, the check is disabled. Non-zero enables the check.
203 * @retval -EINVAL Invalid service ID
205 int32_t __rte_experimental rte_service_set_runstate_mapped_check(uint32_t id,
210 * @b EXPERIMENTAL: this API may change without prior notice
212 * This function runs a service callback from a non-service lcore.
214 * This function is designed to enable gradual porting to service cores, and
215 * to enable unit tests to verify a service behaves as expected.
217 * When called, this function ensures that the service identified by *id* is
218 * safe to run on this lcore. Multi-thread safe services are invoked even if
219 * other cores are simultaneously running them as they are multi-thread safe.
221 * Multi-thread unsafe services are handled depending on the variable
222 * *serialize_multithread_unsafe*:
223 * - When set, the function will check if a service is already being invoked
224 * on another lcore, refusing to run it and returning -EBUSY.
225 * - When zero, the application takes responsibility to ensure that the service
226 * indicated by *id* is not going to be invoked by another lcore. This setting
227 * avoids atomic operations, so is likely to be more performant.
229 * @param id The ID of the service to run
230 * @param serialize_multithread_unsafe This parameter indicates to the service
231 * cores library if it is required to use atomics to serialize access
232 * to mult-thread unsafe services. As there is an overhead in using
233 * atomics, applications can choose to enable or disable this feature
235 * Note that any thread calling this function MUST be a DPDK EAL thread, as
236 * the *rte_lcore_id* function is used to access internal data structures.
238 * @retval 0 Service was run on the calling thread successfully
239 * @retval -EBUSY Another lcore is executing the service, and it is not a
240 * multi-thread safe service, so the service was not run on this lcore
241 * @retval -ENOEXEC Service is not in a run-able state
242 * @retval -EINVAL Invalid service id
244 int32_t __rte_experimental rte_service_run_iter_on_app_lcore(uint32_t id,
245 uint32_t serialize_multithread_unsafe);
249 * @b EXPERIMENTAL: this API may change without prior notice
251 * Start a service core.
253 * Starting a core makes the core begin polling. Any services assigned to it
254 * will be run as fast as possible. The application must ensure that the lcore
255 * is in a launchable state: e.g. call *rte_eal_lcore_wait* on the lcore_id
256 * before calling this function.
259 * @retval -EINVAL Failed to start core. The *lcore_id* passed in is not
260 * currently assigned to be a service core.
262 int32_t __rte_experimental rte_service_lcore_start(uint32_t lcore_id);
266 * @b EXPERIMENTAL: this API may change without prior notice
268 * Stop a service core.
270 * Stopping a core makes the core become idle, but remains assigned as a
274 * @retval -EINVAL Invalid *lcore_id* provided
275 * @retval -EALREADY Already stopped core
276 * @retval -EBUSY Failed to stop core, as it would cause a service to not
277 * be run, as this is the only core currently running the service.
278 * The application must stop the service first, and then stop the
281 int32_t __rte_experimental rte_service_lcore_stop(uint32_t lcore_id);
285 * @b EXPERIMENTAL: this API may change without prior notice
287 * Adds lcore to the list of service cores.
289 * This functions can be used at runtime in order to modify the service core
293 * @retval -EBUSY lcore is busy, and not available for service core duty
294 * @retval -EALREADY lcore is already added to the service core list
295 * @retval -EINVAL Invalid lcore provided
297 int32_t __rte_experimental rte_service_lcore_add(uint32_t lcore);
301 * @b EXPERIMENTAL: this API may change without prior notice
303 * Removes lcore from the list of service cores.
305 * This can fail if the core is not stopped, see *rte_service_core_stop*.
308 * @retval -EBUSY Lcore is not stopped, stop service core before removing.
309 * @retval -EINVAL failed to add lcore to service core mask.
311 int32_t __rte_experimental rte_service_lcore_del(uint32_t lcore);
315 * @b EXPERIMENTAL: this API may change without prior notice
317 * Retrieve the number of service cores currently available.
319 * This function returns the integer count of service cores available. The
320 * service core count can be used in mapping logic when creating mappings
321 * from service cores to services.
323 * See *rte_service_lcore_list* for details on retrieving the lcore_id of each
326 * @return The number of service cores currently configured.
328 int32_t __rte_experimental rte_service_lcore_count(void);
332 * @b EXPERIMENTAL: this API may change without prior notice
334 * Resets all service core mappings. This does not remove the service cores
335 * from duty, just unmaps all services / cores, and stops() the service cores.
336 * The runstate of services is not modified.
340 int32_t __rte_experimental rte_service_lcore_reset_all(void);
344 * @b EXPERIMENTAL: this API may change without prior notice
346 * Enable or disable statistics collection for *service*.
348 * This function enables per core, per-service cycle count collection.
349 * @param id The service to enable statistics gathering on.
350 * @param enable Zero to disable statistics, non-zero to enable.
352 * @retval -EINVAL Invalid service pointer passed
354 int32_t __rte_experimental rte_service_set_stats_enable(uint32_t id,
359 * @b EXPERIMENTAL: this API may change without prior notice
361 * Retrieve the list of currently enabled service cores.
363 * This function fills in an application supplied array, with each element
364 * indicating the lcore_id of a service core.
366 * Adding and removing service cores can be performed using
367 * *rte_service_lcore_add* and *rte_service_lcore_del*.
368 * @param [out] array An array of at least *rte_service_lcore_count* items.
369 * If statically allocating the buffer, use RTE_MAX_LCORE.
370 * @param [out] n The size of *array*.
371 * @retval >=0 Number of service cores that have been populated in the array
372 * @retval -ENOMEM The provided array is not large enough to fill in the
373 * service core list. No items have been populated, call this function
374 * with a size of at least *rte_service_core_count* items.
376 int32_t __rte_experimental rte_service_lcore_list(uint32_t array[], uint32_t n);
380 * @b EXPERIMENTAL: this API may change without prior notice
382 * Get the numer of services running on the supplied lcore.
384 * @param lcore Id of the service core.
385 * @retval >=0 Number of services registered to this core.
386 * @retval -EINVAL Invalid lcore provided
387 * @retval -ENOTSUP The provided lcore is not a service core.
389 int32_t __rte_experimental rte_service_lcore_count_services(uint32_t lcore);
393 * @b EXPERIMENTAL: this API may change without prior notice
395 * Dumps any information available about the service. When id is UINT32_MAX,
396 * this function dumps info for all services.
398 * @retval 0 Statistics have been successfully dumped
399 * @retval -EINVAL Invalid service id provided
401 int32_t __rte_experimental rte_service_dump(FILE *f, uint32_t id);
404 * Returns the number of cycles that this service has consumed
406 #define RTE_SERVICE_ATTR_CYCLES 0
409 * Returns the count of invocations of this service function
411 #define RTE_SERVICE_ATTR_CALL_COUNT 1
415 * @b EXPERIMENTAL: this API may change without prior notice
417 * Get an attribute from a service.
419 * @retval 0 Success, the attribute value has been written to *attr_value*.
420 * -EINVAL Invalid id, attr_id or attr_value was NULL.
422 int32_t __rte_experimental rte_service_attr_get(uint32_t id, uint32_t attr_id,
423 uint32_t *attr_value);
427 * @b EXPERIMENTAL: this API may change without prior notice
429 * Reset all attribute values of a service.
431 * @param id The service to reset all statistics of
432 * @retval 0 Successfully reset attributes
433 * -EINVAL Invalid service id provided
435 int32_t __rte_experimental rte_service_attr_reset_all(uint32_t id);
442 #endif /* _RTE_SERVICE_H_ */