1 // -----------------------------------------------------------------------
2 // Copyright (C) 2006 - 2008 FRESCOR consortium partners:
4 // Universidad de Cantabria, SPAIN
5 // University of York, UK
6 // Scuola Superiore Sant'Anna, ITALY
7 // Kaiserslautern University, GERMANY
8 // Univ. Politécnica Valencia, SPAIN
9 // Czech Technical University in Prague, CZECH REPUBLIC
11 // Thales Communication S.A. FRANCE
12 // Visual Tools S.A. SPAIN
13 // Rapita Systems Ltd UK
16 // See http://www.frescor.org for a link to partners' websites
18 // FRESCOR project (FP6/2005/IST/5-034026) is funded
19 // in part by the European Union Sixth Framework Programme
20 // The European Union is not liable of any use that may be
24 // based on previous work (FSF) done in the FIRST project
26 // Copyright (C) 2005 Mälardalen University, SWEDEN
27 // Scuola Superiore S.Anna, ITALY
28 // Universidad de Cantabria, SPAIN
29 // University of York, UK
31 // FSF API web pages: http://marte.unican.es/fsf/docs
32 // http://shark.sssup.it/contrib/first/docs/
34 // This file is part of FRSH (FRescor ScHeduler)
36 // FRSH is free software; you can redistribute it and/or modify it
37 // under terms of the GNU General Public License as published by the
38 // Free Software Foundation; either version 2, or (at your option) any
39 // later version. FRSH is distributed in the hope that it will be
40 // useful, but WITHOUT ANY WARRANTY; without even the implied warranty
41 // of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
42 // General Public License for more details. You should have received a
43 // copy of the GNU General Public License along with FRSH; see file
44 // COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,
45 // Cambridge, MA 02139, USA.
47 // As a special exception, including FRSH header files in a file,
48 // instantiating FRSH generics or templates, or linking other files
49 // with FRSH objects to produce an executable application, does not
50 // by itself cause the resulting executable application to be covered
51 // by the GNU General Public License. This exception does not
52 // however invalidate any other reasons why the executable file might be
53 // covered by the GNU Public License.
54 // As a special exception, if you include this header file into source
55 // files to be compiled, this header file does not by itself cause
56 // the resulting executable to be covered by the GNU General Public
57 // License. This exception does not however invalidate any other
58 // reasons why the executable file might be covered by the GNU General
60 // -----------------------------------------------------------------------
61 //frsh_spare_capacity.h
62 //==============================================
63 // ******** ******* ******** ** **
64 // **///// /**////** **////// /** /**
65 // ** /** /** /** /** /**
66 // ******* /******* /********* /**********
67 // **//// /**///** ////////** /**//////**
68 // ** /** //** /** /** /**
69 // ** /** //** ******** /** /**
70 // // // // //////// // //
72 // FRSH(FRescor ScHeduler), pronounced "fresh"
73 //==============================================
74 #ifndef _FRSH_SPARE_CAPACITY_H_
75 #define _FRSH_SPARE_CAPACITY_H_
79 #include "frsh_spare_capacity_types.h"
80 #include "frsh_core_types.h"
81 #include "frsh_core.h"
86 * @file frsh_spare_capacity.h
89 #define FRSH_SPARE_CAPACITY_MODULE_SUPPORTED 1
93 * @file frsh_spare_capacity.h
95 * This file contains the function prototypes for the usage of
96 * spare capacity and dynamic reclamation.
100 * @defgroup sparecapacity Spare Capacity module
102 * This module manages the partition of exceeding capacity at
103 * negotiation time between the vres that express their desire of
104 * optional requirements.
108 * - Allowing to define a range of budget and period instead of
109 * giving WCET values only. This range can be continuous or
112 * - Specifying a fairness measurement to compete with other vres in the
113 * division of the share.
115 * - Specifying a stability_time time for vres that need to have
116 * a assigned capacity remain const during time (they would be
117 * annoyed if their budget or period would change).
119 * There are no specific negotiation calls because the algorithms used
120 * in the core module take already these min-max ranges into account.
122 * An operation is available for applications to ask for a stability
123 * period of a specified length. The framework will then return the
124 * total capacity (execution time budget and virtual resource period)
125 * that the application is guaranteed to receive in this stability
126 * period. The rationale for this service is that jobs may span a
127 * number of virtual resource periods, and need to have a guaranteed
128 * amount of capacity before they can choose a higher quality (longer
129 * execution time) method, when multiple methods are available. Also
130 * applications may require that the capacity provided to them and
131 * hence the quality of results produced remains consistent for a
132 * period of time, so that consistent behaviour is provided for the
133 * user (e.g. multimedia applications).
135 * Requesting a new stability period has the effect of cancelling any
136 * previous one. So a subsequent request for stability up to the same
137 * point in time could return a lower total capacity, if spare capacity
138 * re-allocation is in progress due to the admission of a new
139 * application. If a stability period expires without having explicitly
140 * set a new one, the system may decide to perform a reallocation of
141 * spare resources at that point, or may defer this decision to some
142 * future point in time when it is appropriate. In both cases, a new
143 * stability period will start when the new spare capacity assignment
147 * NOTE: When we talk here about "spare capacity" we mean STATIC extra
148 * capacity at NEGOTIATION TIME. This is the minimum capacity
149 * that the vres will get based on contract negotiation.
150 * This capacity is distributed based on the importance and
151 * weight values and is known before-hand at the beginning of
154 * Besides this extra capacity, there is the DYNAMIC extra
155 * capacity that results at RUN TIME from earlier job endings of
156 * bounded-workload vres. This extra capacity can vary
157 * between each execution period and is not known beforehand.
159 * This extra run-time capacity is assigned if the following 2
160 * conditions are met:
162 * - FRSH_DYNAMIC_RECLAIMING_MODULE_SUPPORTED is defined to 1
163 * (in frsh_dynamic_reclaiming.h).
165 * - There is at least one vres willing to accept this extra
167 * - A FRSH_BOUNDED workload vres with a range of Budget
168 * and Period that can absorb the extra capacity and
169 * whose static_time period is not active.
170 * - An INDETERMINATE workload vres with an active
171 * static_time period.
178 * frsh_contract_set_reclamation_params()
180 * The operation updates the specified contract parameters object by
181 * setting its maximum usable budget, minimum period, granularity,
182 * utilization set, weight, and importance to the specified input
185 * @param contract Contract object
186 * @param stability_time Time in which FRSH guarantees that the
187 * assigned budget and period will remain permanent
188 * even across renegotiations.
189 * @param budget_max The maximum budget that the vres aspires to
191 * @param period_min The minimum period (therefore minimal
192 * interarrival time) that the vres may get for
193 * awakening and replenishment periods.
194 * @param granularity FRSH_CONTINUOUS: Use min-max values,
195 * FRSH_DISCRETE: Use utilization_set.
196 * @param utilization_set A structure of discrete triples (budget,
198 * @param importance non-cooperative urgency indicator. Vres with
199 * higher importance will get all spare capacity des
200 * @param weight cooperative urgency indicator. At equal
201 * importance, spare capacity will be distributed
202 * proportionally to weight levels.
205 * @return 0 if successful \n
206 * FRSH_ERR_BAD_ARGUMENT : if contract is NULL \b or \n
207 * (budget_max value is grater than period_max or smaller than budget_min) \b or \n
208 * (period_min is smaller than budget_mint or larger than period_max) \b or \n
209 * (granularity is neither FRSH_CONTINUOUS nor FRSH_DISCRETE) \b or \n
210 * (granularity is FRSH_CONTINUOUS and
211 * utilization_set is not FRSH_NULL_UTILIZATION_SET) \b or \n
212 * (granularity is FRSH_DISCRETE and
213 * utilization_set is FRSH_NULL_UTILIZATION_SET \b or \n
214 * (utilization_set is not FRSH_NULL_UTILIZATION_SET and
215 * (size of utilization_set less than 2 or greater
216 * than FRSH_MAX_N_UTILIZATION_VALUES) ) \b or \n
217 * (weight < 0) \b or \n
218 * (importance is less than 1 or greater than FRSH_N_IMPORTANCE_LEVELS) \b or \n
219 * (the utilization_set elements are not in increasing utilization order) \b or \n
220 * (the first utilization value in the utilization_set does not match
221 * the pair (budget_min, period_max) of the contract) \b or \n
222 * (the last utilization value in the utilization_set does not match
223 * the pair (budget_max, period_min) of the contract)
226 int frsh_contract_set_reclamation_params(frsh_contract_t *contract,
227 const frsh_rel_time_t *stability_time,
228 const frsh_rel_time_t *budget_max,
229 const frsh_rel_time_t *period_min,
230 frsh_granularity_t granularity,
231 const frsh_utilization_set_t *utilization_set,
236 * frsh_contract_get_reclamation_params()
238 * The operation obtains the sparecapacity contract parameters from
239 * the contract object.
241 * @see frsh_set_contract_reclamation_parameters() for the meaning of
244 * Only the utilization_values of the utilization_set
245 * that are in use, are copied (according to its size field).
248 * @return 0 if successful \n
249 * FRSH_ERR_BAD_ARGUMENT : if contract is NULL
252 int frsh_contract_get_reclamation_params
253 (const frsh_contract_t *contract,
254 frsh_rel_time_t *stability_time,
255 frsh_rel_time_t *budget_max,
256 frsh_rel_time_t *period_min,
257 frsh_granularity_t *granularity,
258 frsh_utilization_set_t *utilization_set,
264 * frsh_vres_get_remaining_stability_time()
266 * This operation returns the stability_time for the vres.
268 * @return 0 if successful \n
269 * FRSH_ERR_BAD_ARGUMENT : if the value of the vres argument is not in range or
270 * capacity is NULL \n
271 * FRSH_ERR_NOT_SCHEDULED_CALLING_THREAD : if the calling thread is not
272 * scheduled under FRSH \n
273 * FRSH_ERR_INVALID_SCHEDULER_REPLY : the scheduler is wrong or not
275 * FRSH_ERR_NOT_CONTRACTED_VRES : if the vres has been cancelled or it
279 int frsh_vres_get_remaining_stability_time(frsh_vres_id_t vres,
280 frsh_rel_time_t *stability_time);
284 * frsh_vres_set_stability_time:
286 * Dynamically set the stability time for a given virtual resource to
287 * the specified interval. This operation sets a new value for the
288 * stability time associated with the virtual resource. As a result of
289 * this call the system may change the allocation of resources to the
290 * current virtual resource. Regardless of whether the resources are
291 * reallocated or not, the call resets the stability period so that
292 * the level of resources allocated to the virtual resource is kept
293 * stable for at least the duration of the requested interval. The
294 * possibly new values of budget and period are returned in the
295 * corresponding parameters
298 int frsh_vres_set_stability_time
299 (frsh_vres_id_t vres,
300 const frsh_rel_time_t *stability_time,
301 frsh_rel_time_t *budget,
302 frsh_rel_time_t *period);
306 * frsh_resource_get_capacity()
308 * This operation gets the spare capacity currently assigned to an
309 * importance level. The capacity is the number obtained divided by
310 * UINT32_MAX, and it represents the processor or network
313 * @return 0 if successful \n
314 * FRSH_ERR_BAD_ARGUMENT : if the value of the vres argument is not in range or
315 * capacity is NULL \n
316 * FRSH_ERR_NOT_SCHEDULED_CALLING_THREAD : if the calling thread is not
317 * scheduled under the FRSH \n
318 * FRSH_ERR_INVALID_SCHEDULER_REPLY : the scheduler is wrong or not
320 * FRSH_ERR_NOT_CONTRACTED_VRES : if the vres has been cancelled or it
324 int frsh_resource_get_capacity(const frsh_resource_type_t resource_type,
325 const frsh_resource_id_t resource_id,
326 const int importance,
331 * frsh_resource_get_total_weight()
333 * This operation calculates the sum of the weight parameters for all
334 * vres in the system for a certain importance level at a specific
337 * @return 0 if successful \n
338 * FRSH_ERR_BAD_ARGUMENT : if the value of the vres argument is not in range or
339 * total_weight is NULL \n
340 * FRSH_ERR_NOT_SCHEDULED_CALLING_THREAD : if the calling thread is not
341 * scheduled under FRSH \n
342 * FRSH_ERR_INVALID_SCHEDULER_REPLY : the scheduler is wrong or not
344 * FRSH_ERR_NOT_CONTRACTED_VRES : if the vres has been cancelled or it
347 int frsh_resource_get_total_weight
348 (const frsh_resource_type_t resource_type,
349 const frsh_resource_id_t resource_id,
350 const int importance,
351 uint32_t *total_weight);
355 * frsh_vres_decrease_capacity()
357 * This operation is mainly intended for distributed systems but may
358 * also be useful for control application in uniprocessor systems.
360 * It allows the vres to ask for less budget and period that what he
361 * has actually received. The request must be compatible with the
362 * rest of contract parameters.
365 int frsh_vres_decrease_capacity(frsh_vres_id_t vres,
366 frsh_rel_time_t new_budget,
367 frsh_rel_time_t new_period);
374 #endif // _FRSH_SPARE_CAPACITY_H_