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2 | pj | 1 | /* |
2 | * Project: S.Ha.R.K. |
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3 | * |
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4 | * Coordinators: |
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5 | * Giorgio Buttazzo <giorgio@sssup.it> |
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6 | * Paolo Gai <pj@gandalf.sssup.it> |
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7 | * |
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8 | * Authors : |
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9 | * Paolo Gai <pj@gandalf.sssup.it> |
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10 | * Massimiliano Giorgi <massy@gandalf.sssup.it> |
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11 | * Luca Abeni <luca@gandalf.sssup.it> |
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12 | * (see the web pages for full authors list) |
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13 | * |
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14 | * ReTiS Lab (Scuola Superiore S.Anna - Pisa - Italy) |
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15 | * |
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16 | * http://www.sssup.it |
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17 | * http://retis.sssup.it |
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18 | * http://shark.sssup.it |
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19 | */ |
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20 | |||
21 | /** |
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22 | ------------ |
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38 | pj | 23 | CVS : $Id: ss.c,v 1.4 2003-01-07 17:07:51 pj Exp $ |
2 | pj | 24 | |
25 | File: $File$ |
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38 | pj | 26 | Revision: $Revision: 1.4 $ |
27 | Last update: $Date: 2003-01-07 17:07:51 $ |
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2 | pj | 28 | ------------ |
29 | |||
30 | This file contains the aperiodic Sporadic Server (SS). |
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31 | |||
32 | Note: in the following, server capacity and server budget are used as |
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33 | synonyms. |
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34 | |||
35 | When scheduling in background the flags field has the SS_BACKGROUND bit set |
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36 | |||
37 | When scheduling a task because it is pointed by another task via shadows, |
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38 | the task have to be extracted from the wait queue or the master level. To |
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39 | check this we have to look at the activated field; it is != NIL if a task |
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40 | is inserted into the master level. Only a task at a time can be inserted |
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41 | into the master level. |
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42 | |||
43 | The capacity of the server must be updated |
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44 | - when scheduling a task normally |
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45 | - when scheduling a task because it is pointed by a shadow |
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46 | but not when scheduling in background. |
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47 | |||
48 | When a task is extracted from the system no scheduling has to be done |
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49 | until the task reenter into the system. To implement this, when a task |
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50 | is extracted we block the background scheduling (the scheduling with the |
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51 | master level is already blocked because the activated field is not |
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52 | reset to NIL) using the SS_BACKGROUNDBLOCK bit. |
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53 | |||
54 | nact[p] is -1 if the task set the activations to SKIP, >= 0 otherwise |
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55 | |||
56 | In contrast to classic SS scheme, the activation happens when |
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57 | a task does a create request while there is positive budget (instead to |
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58 | becomes active when there is a running task with priority higger then or |
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59 | equal to the server). |
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60 | So the replenish time is estabished on task arrival time. Replenish time |
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61 | is calculated as usual: activation time + server period. |
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62 | When the server ends its budget, becomes not active until a replenishment |
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63 | occurs. |
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64 | |||
65 | When a task ends its computation and there are no tasks to schedule or, |
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66 | again, the server budget ends, a replenish amount is posted so that, when |
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67 | replenish time fires, the server budget will be updated. Replenish |
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68 | amount is determined depending on how much time tasks have ran. |
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69 | Replenish amount does't takes into account periods during witch tasks |
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70 | handled by SS are preempted. |
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71 | |||
72 | There are two models used to handle a task is running into a critic section |
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73 | (owning a mutex): "nostop" model and "stop" model. |
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74 | Using the "nostop" model, a task that runs into a critic section is not |
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75 | stopped when server ends its budget. This is done so higger priority tasks |
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76 | waiting for mutex are not blocked for so much time to replenish time occurs. |
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77 | When this happens the server capacity becomes negative and the replenish |
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78 | amount takes into account the negative budget part. |
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79 | With "stop" model running task is always suspended when server budget ends. |
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80 | If suspended task owns a mutex shared with higger priority task, the last |
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81 | one cannot runs until the mutex will be released. Higger priority task |
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82 | must waits at least upto next replenish time, when server budget will be |
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83 | refulled and suspended task runs again. |
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84 | |||
85 | Using "nostop" model, SS can uses more bandwidth respect to assigned |
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86 | capacity (due to negative budgets). So, calculating the guarantee, the |
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87 | longer critic section of all tasks handled by SS must be considered. |
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88 | |||
89 | SS can be used either with EDF or RM master level. |
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90 | |||
91 | Read SS.h for further details. |
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92 | |||
93 | **/ |
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94 | |||
95 | /* |
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96 | * Copyright (C) 2000 Paolo Gai |
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97 | * |
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98 | * This program is free software; you can redistribute it and/or modify |
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99 | * it under the terms of the GNU General Public License as published by |
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100 | * the Free Software Foundation; either version 2 of the License, or |
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101 | * (at your option) any later version. |
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102 | * |
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103 | * This program is distributed in the hope that it will be useful, |
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104 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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105 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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106 | * GNU General Public License for more details. |
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107 | * |
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108 | * You should have received a copy of the GNU General Public License |
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109 | * along with this program; if not, write to the Free Software |
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110 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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111 | * |
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112 | */ |
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113 | |||
114 | |||
115 | #include <stdlib.h> |
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116 | #include <modules/ss.h> |
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117 | #include <ll/stdio.h> |
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118 | #include <ll/string.h> |
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119 | |||
120 | #include <ll/sys/ll/event.h> |
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121 | |||
122 | #include <kernel/const.h> |
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123 | #include <kernel/model.h> |
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124 | #include <kernel/model.h> |
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125 | #include <kernel/descr.h> |
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126 | #include <kernel/var.h> |
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127 | #include <kernel/func.h> |
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38 | pj | 128 | #include <kernel/trace.h> |
2 | pj | 129 | |
130 | /* For debugging purpose */ |
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131 | //#define DEBUG 1 |
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132 | |||
133 | /*+ Status used in the level +*/ |
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134 | #define SS_WAIT APER_STATUS_BASE /*+ waiting the service +*/ |
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135 | |||
136 | /*+ Some useful macros +*/ |
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137 | #define BACKGROUND_ON (lev->flags & SS_BACKGROUND) |
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138 | |||
139 | extern struct event *firstevent; |
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140 | |||
141 | /*+ the level redefinition for the Sporadic Server +*/ |
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142 | typedef struct { |
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143 | level_des l; /*+ the standard level descriptor +*/ |
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144 | |||
145 | /* The wcet are stored in the task descriptor's priority |
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146 | field, so no other fields are needed */ |
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147 | |||
148 | int nact[MAX_PROC]; /*+ number of pending activations +*/ |
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149 | |||
150 | struct timespec lastdline; /*+ the last deeadline assigned to |
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151 | a SS task +*/ |
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152 | |||
153 | int Cs; /*+ server capacity +*/ |
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154 | int availCs; /*+ server avail time +*/ |
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155 | int period; /*+ Server period +*/ |
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156 | |||
157 | bandwidth_t U; /*+ the used bandwidth by the server +*/ |
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158 | |||
29 | pj | 159 | IQUEUE wait; /*+ the wait queue of the SS +*/ |
2 | pj | 160 | PID activated; /*+ the task inserted in another queue +*/ |
161 | |||
162 | int flags; /*+ the init flags... +*/ |
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163 | |||
164 | |||
165 | LEVEL scheduling_level; |
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166 | |||
167 | int replenishment[SS_MAX_REPLENISH]; /*+ contains replenish amounts +*/ |
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168 | int rfirst,rlast; /*+ first and last valid replenish |
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169 | in replenish queue +*/ |
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170 | int rcount; /*+ queued replenishments +*/ |
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171 | |||
172 | int replenish_amount; /*+ partial replenishments before post +*/ |
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173 | ss_status server_active; /*+ Is server active? +*/ |
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174 | |||
175 | } SS_level_des; |
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176 | |||
177 | /*+ function prototypes +*/ |
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38 | pj | 178 | void SS_internal_status(LEVEL l); |
2 | pj | 179 | static void SS_replenish_timer(void *arg); |
180 | /*-------------------------------------------------------------------*/ |
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181 | |||
182 | /*** Utility functions ***/ |
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183 | |||
184 | |||
185 | /* These are for dinamic queue. **Disabled** */ |
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186 | #if 0 |
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187 | /* These routines are not tested, be carefull */ |
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188 | |||
189 | /*+ SS local memory allocator. |
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190 | Can be used for performance optimization. |
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191 | The interface is the same of kern_alloc() +*/ |
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192 | void inline * ss_alloc(DWORD b) { |
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193 | /* Now simply wraps to standard kernel alloc */ |
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194 | return kern_alloc(b); |
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195 | } |
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196 | |||
197 | void ssq_inslast(LEVEL l, replenishq *elem) { |
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198 | |||
199 | SS_level_des *lev = (SS_level_des *) level_table[l]; |
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200 | |||
201 | if(lev->rqueue_last == NULL) { /* empty queue */ |
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202 | lev->rqueue_last=elem; |
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203 | lev->rqueue_first=elem; |
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204 | return; |
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205 | } |
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206 | elem->next = NULL; |
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207 | lev->rqueue_last->next = elem; |
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208 | lev->rqueue_last = elem; |
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209 | } |
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210 | |||
211 | replenishq *ssq_getfirst(LEVEL l) { |
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212 | |||
213 | SS_level_des *lev = (SS_level_des *) level_table[l]; |
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214 | replenishq *tmp; |
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215 | |||
216 | if(lev->rqueue_first == NULL) { /* empty queue */ |
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217 | return 0; |
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218 | } |
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219 | tmp = lev->rqueue_first; |
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220 | lev->rqueue_first = tmp->next; |
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221 | if(lev->rqueue_first == NULL) { /* no more elements */ |
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222 | lev->rqueue_last = NULL; |
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223 | } |
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224 | tmp->next = NULL; /* to remove dangling pointer */ |
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225 | return tmp; |
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226 | } |
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227 | #endif |
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228 | |||
229 | /* For queue implemented with array. |
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230 | SS_MAX_REPLENISH array size assumed */ |
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231 | |||
232 | /*+ Insert an element at tail of replenish queue |
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233 | LEVEL l module level |
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234 | int amount element to insert |
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235 | |||
236 | RETURNS: |
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237 | |||
238 | NIL no more space for insertion +*/ |
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239 | static inline int ssq_inslast (LEVEL l, int amount) { |
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240 | |||
241 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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242 | |||
243 | #ifdef DEBUG |
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244 | kern_printf("insl "); |
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245 | #endif |
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246 | |||
247 | if (lev->rcount == SS_MAX_REPLENISH) { |
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248 | return NIL; /* no more space in the queue */ |
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249 | } |
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250 | |||
251 | lev->replenishment[lev->rlast++] = amount; |
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252 | lev->rlast %= SS_MAX_REPLENISH; |
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253 | lev->rcount++; |
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254 | #ifdef DEBUG |
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255 | printf_xy(0,0,WHITE,"%d",lev->rcount); |
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256 | #endif |
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257 | |||
258 | return 0; |
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259 | } |
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260 | |||
261 | /*+ Get first element from replenish queue |
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262 | LEVEL l module level |
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263 | |||
264 | RETURS: |
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265 | extracted element |
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266 | NIL on empty queue +*/ |
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267 | static inline int ssq_getfirst (LEVEL l) { |
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268 | |||
269 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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270 | int tmp; |
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271 | |||
272 | #ifdef DEBUG |
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273 | kern_printf("getf "); |
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274 | #endif |
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275 | |||
276 | if (lev->rcount == 0) { |
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277 | return NIL; /* empty queue */ |
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278 | } |
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279 | tmp = lev->replenishment[lev->rfirst++]; |
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280 | lev->rfirst %= SS_MAX_REPLENISH; |
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281 | lev->rcount--; |
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282 | #ifdef DEBUG |
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283 | printf_xy(0,0,WHITE,"%d",lev->rcount); |
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284 | #endif |
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285 | return tmp; |
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286 | } |
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287 | |||
288 | /*+ Enquire for empty queue |
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289 | LEVEL l module level |
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290 | |||
291 | RETURS: |
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292 | |||
293 | 1 queue is empty +*/ |
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294 | static inline int ssq_isempty (LEVEL l) { |
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295 | |||
296 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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297 | |||
298 | return !(lev->rcount); |
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299 | |||
300 | // if(lev->rcount == 0) |
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301 | // return 1; |
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302 | // return 0; |
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303 | } |
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304 | |||
305 | /*+ Set replenish amount for budget used during task execution |
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306 | LEVEL l module level */ |
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307 | static inline void SS_set_ra(LEVEL l) |
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308 | { |
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309 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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310 | |||
311 | /* replenish must be set when the server is still active */ |
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312 | if(lev->server_active == SS_SERVER_ACTIVE) { |
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313 | lev->server_active = SS_SERVER_NOTACTIVE; |
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314 | if(ssq_inslast(l, lev->replenish_amount) == NIL) { |
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315 | kern_printf("SS: no more space to post replenishment\n"); |
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316 | kern_printf("You should recompile setting higher SS_MAX_REPLENISH into include/modules/ss.h\n"); |
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38 | pj | 317 | SS_internal_status(l); |
14 | pj | 318 | kern_raise(XINVALID_SS_REPLENISH,exec_shadow); |
2 | pj | 319 | #ifdef DEBUG |
320 | sys_abort(-1); |
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321 | exit(-1); |
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322 | #endif |
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323 | } |
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324 | lev->replenish_amount = 0; |
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325 | } |
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326 | else { |
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327 | kern_printf("SS not active when posting R.A.\n"); |
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38 | pj | 328 | SS_internal_status(l); |
14 | pj | 329 | kern_raise(XINVALID_SS_REPLENISH,exec_shadow); |
2 | pj | 330 | #ifdef DEBUG |
331 | sys_abort(-1); |
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332 | exit(-1); |
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333 | #endif |
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334 | } |
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335 | } |
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336 | /* ------------------------------------------------------------------ */ |
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337 | |||
338 | /* This static function activates the task pointed by lev->activated) */ |
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339 | static inline void SS_activation(SS_level_des *lev) |
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340 | { |
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341 | /* those two defines are for readableness */ |
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342 | PID p; |
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343 | LEVEL m; |
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344 | |||
345 | JOB_TASK_MODEL j; /* the guest model */ |
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346 | // struct timespec ty; |
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347 | |||
348 | #ifdef DEBUG |
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349 | kern_printf("SS_acti "); |
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350 | #endif |
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351 | |||
352 | p = lev->activated; |
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353 | m = lev->scheduling_level; |
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354 | |||
355 | #if 0 |
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356 | /* if server is active, replenish time already set */ |
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357 | if (lev->server_active == SS_SERVER_NOTACTIVE) { |
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358 | lev->server_active = SS_SERVER_ACTIVE; |
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359 | /* set replenish time */ |
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360 | TIMESPEC_ASSIGN(&ty, &proc_table[p].request_time); |
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361 | ADDUSEC2TIMESPEC(lev->period, &ty); |
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362 | TIMESPEC_ASSIGN(&lev->lastdline, &ty); |
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363 | #ifdef DEBUG |
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364 | kern_printf("RT:%d.%d ",ty.tv_sec,ty.tv_nsec); |
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365 | #endif |
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366 | kern_event_post(&ty, SS_replenish_timer, (void *) l); |
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367 | } |
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368 | #endif |
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369 | |||
370 | job_task_default_model(j,lev->lastdline); |
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371 | job_task_def_period(j,lev->period); |
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38 | pj | 372 | level_table[m]->private_insert(m,p,(TASK_MODEL *)&j); |
2 | pj | 373 | |
374 | #ifdef DEBUG |
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375 | kern_printf("PID:%p lastdl:%d.%d ",p,lev->lastdline.tv_sec,lev->lastdline.tv_nsec); |
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376 | #endif |
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377 | } |
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378 | |||
379 | /*+ |
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380 | Before call capacity_timer, update server capacity |
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381 | and replenish amount. |
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382 | +*/ |
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383 | static void SS_capacity_timer(void *arg) { |
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384 | |||
385 | LEVEL l = (LEVEL)arg; |
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386 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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387 | struct timespec ty; |
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388 | int tx; |
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389 | |||
390 | #ifdef DEBUG |
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391 | kern_printf("SS_captim "); |
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392 | #endif |
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393 | |||
394 | /* set replenish amount */ |
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395 | /* task was running while budget ends */ |
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396 | lev->server_active = SS_SERVER_NOTACTIVE; |
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397 | SUBTIMESPEC(&schedule_time, &cap_lasttime, &ty); |
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398 | tx = TIMESPEC2USEC(&ty); |
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399 | lev->availCs -= tx; |
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400 | if(ssq_inslast(l, tx+lev->replenish_amount) == NIL) { |
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401 | kern_printf("SS: no more space to post replenishment\n"); |
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402 | kern_printf(" You should recompile setting higher SS_MAX_REPLENISH into include/modules/ss.h\n"); |
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38 | pj | 403 | SS_internal_status(l); |
14 | pj | 404 | kern_raise(XINVALID_SS_REPLENISH,exec_shadow); |
2 | pj | 405 | #ifdef DEBUG |
406 | sys_abort(-1); |
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407 | exit(-1); |
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408 | #endif |
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409 | } |
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410 | lev->replenish_amount = 0; |
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411 | capacity_timer(NULL); |
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412 | } |
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413 | |||
414 | static void SS_replenish_timer(void *arg) |
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415 | { |
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416 | LEVEL l = (LEVEL)arg; |
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417 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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418 | struct timespec ty; |
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419 | int amount; |
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420 | |||
421 | #ifdef DEBUG |
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422 | kern_printf("SS_reptim "); |
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423 | #endif |
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424 | |||
425 | /* availCs may be <0 because a task executed via a shadow for many time |
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426 | lev->activated == NIL only if the prec task was finished and there |
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427 | was not any other task to be put in the ready queue |
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428 | ... we are now activating the next task */ |
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429 | if ((amount = ssq_getfirst(l)) != NIL) { |
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430 | lev->availCs += amount; |
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431 | #ifdef DEBUG |
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432 | kern_printf("AvaCs=%d ",lev->availCs); |
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433 | #endif |
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434 | if (lev->availCs > lev->Cs) { |
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435 | /* This should not be possible. I do so for robustness. */ |
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436 | lev->availCs = lev->Cs; |
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437 | #ifdef DEBUG |
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438 | kern_printf("SS warning: budget higher then server capacity. Set to Cs."); |
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439 | #endif |
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440 | } |
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441 | if (lev->availCs <= 0) { |
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442 | /* we can be here if nostop model is used */ |
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443 | #ifdef DEBUG |
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444 | kern_printf("WARNING: SS has non positive capacity after replenish."); |
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445 | #endif |
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446 | /* if there isn't pending replenishment and server |
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447 | is not active we must refull somehow. |
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448 | Otherwise SS remains not active forever */ |
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449 | if(ssq_isempty(l) && lev->server_active == SS_SERVER_NOTACTIVE) { |
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450 | lev->availCs = lev->Cs; |
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451 | kern_printf("SS was full replenished due to irreversible non positive budget!!!\n"); |
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452 | kern_printf("You should review your time extimation for critical sections ;)\n"); |
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453 | } |
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454 | } |
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455 | } |
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456 | else { |
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457 | /* replenish queue is empty */ |
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458 | kern_printf("Replenish Timer fires but no Replenish Amount defined\n"); |
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38 | pj | 459 | SS_internal_status(l); |
14 | pj | 460 | kern_raise(XINVALID_SS_REPLENISH,exec_shadow); |
2 | pj | 461 | #ifdef DEBUG |
462 | sys_abort(-1); |
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463 | exit(-1); |
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464 | #endif |
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465 | } |
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466 | |||
467 | if (lev->availCs > 0 && lev->activated == NIL) { |
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29 | pj | 468 | if (iq_query_first(&lev->wait) != NIL) { |
469 | lev->activated = iq_getfirst(&lev->wait); |
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2 | pj | 470 | /* if server is active, replenish time already set */ |
471 | if (lev->server_active == SS_SERVER_NOTACTIVE) { |
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472 | lev->server_active = SS_SERVER_ACTIVE; |
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473 | /* set replenish time */ |
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38 | pj | 474 | kern_gettime(&ty); |
2 | pj | 475 | ADDUSEC2TIMESPEC(lev->period, &ty); |
476 | TIMESPEC_ASSIGN(&lev->lastdline, &ty); |
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477 | #ifdef DEBUG |
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478 | kern_printf("RT:%d.%d ",ty.tv_sec,ty.tv_nsec); |
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479 | #endif |
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480 | kern_event_post(&ty, SS_replenish_timer, (void *) l); |
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481 | } |
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482 | SS_activation(lev); |
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483 | event_need_reschedule(); |
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484 | } |
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485 | } |
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486 | } |
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487 | |||
488 | static char *SS_status_to_a(WORD status) |
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489 | { |
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490 | if (status < MODULE_STATUS_BASE) |
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38 | pj | 491 | return "Unavailable"; //status_to_a(status); |
2 | pj | 492 | |
493 | switch (status) { |
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494 | case SS_WAIT : return "SS_Wait"; |
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495 | default : return "SS_Unknown"; |
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496 | } |
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497 | } |
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498 | |||
499 | |||
500 | /*-------------------------------------------------------------------*/ |
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501 | |||
502 | /*** Level functions ***/ |
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503 | |||
38 | pj | 504 | void SS_internal_status(LEVEL l) |
2 | pj | 505 | { |
506 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
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29 | pj | 507 | PID p = iq_query_first(&lev->wait); |
2 | pj | 508 | |
509 | kern_printf("On-line guarantee : %s\n", |
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510 | (lev->flags & SS_ENABLE_GUARANTEE_EDF || |
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511 | lev->flags & SS_ENABLE_GUARANTEE_RM )?"On":"Off"); |
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512 | |||
513 | kern_printf("Used Bandwidth : %u/%u\n",lev->U,MAX_BANDWIDTH); |
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514 | kern_printf("Period : %d\n",lev->period); |
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515 | kern_printf("Capacity : %d\n",lev->Cs); |
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516 | kern_printf("Avail capacity : %d\n",lev->availCs); |
||
517 | kern_printf("Server is %sactive\n", |
||
518 | (lev->server_active == SS_SERVER_NOTACTIVE ? "not ":"")); |
||
519 | kern_printf("Pending RAs : %d\n",lev->rcount); |
||
520 | |||
521 | if (lev->activated != NIL) |
||
522 | kern_printf("Activated: Pid: %d Name: %10s Dl: %ld.%ld Nact: %d Stat: %s\n", |
||
523 | lev->activated, |
||
524 | proc_table[lev->activated].name, |
||
29 | pj | 525 | iq_query_timespec(lev->activated,&lev->wait)->tv_sec, |
526 | iq_query_timespec(lev->activated,&lev->wait)->tv_nsec, |
||
2 | pj | 527 | lev->nact[lev->activated], |
528 | SS_status_to_a(proc_table[lev->activated].status)); |
||
529 | |||
530 | while (p != NIL) { |
||
531 | kern_printf("Pid: %d\tName: %10s\tStatus: %s\n", |
||
532 | p, |
||
533 | proc_table[p].name, |
||
534 | SS_status_to_a(proc_table[p].status)); |
||
29 | pj | 535 | p = iq_query_next(p, &lev->wait); |
2 | pj | 536 | } |
537 | } |
||
538 | |||
38 | pj | 539 | static PID SS_public_schedulerbackground(LEVEL l) |
2 | pj | 540 | { |
541 | /* the SS catch the background time to exec aperiodic activities */ |
||
542 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
543 | |||
544 | #ifdef DEBUG |
||
545 | kern_printf("SS_levschbg "); |
||
546 | #endif |
||
547 | |||
548 | lev->flags |= SS_BACKGROUND; |
||
549 | |||
550 | if (lev->flags & SS_BACKGROUND_BLOCK) |
||
551 | return NIL; |
||
552 | else |
||
29 | pj | 553 | return iq_query_first(&lev->wait); |
2 | pj | 554 | } |
555 | |||
556 | /* The on-line guarantee is enabled only if the appropriate flag is set... */ |
||
38 | pj | 557 | static int SS_public_guaranteeEDF(LEVEL l, bandwidth_t *freebandwidth) |
2 | pj | 558 | { |
559 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
560 | |||
561 | #ifdef DEBUG |
||
562 | kern_printf("SS_levguarEDF "); |
||
563 | #endif |
||
564 | |||
565 | if (*freebandwidth >= lev->U) { |
||
566 | *freebandwidth -= lev->U; |
||
567 | return 1; |
||
568 | } |
||
569 | else |
||
570 | return 0; |
||
571 | } |
||
572 | |||
38 | pj | 573 | static int SS_public_guaranteeRM(LEVEL l, bandwidth_t *freebandwidth) |
2 | pj | 574 | { |
575 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
576 | |||
577 | #ifdef DEBUG |
||
578 | kern_printf("SS_levguarRM "); |
||
579 | #endif |
||
580 | |||
581 | if (*freebandwidth > lev->U + RM_MINFREEBANDWIDTH) { |
||
582 | *freebandwidth -= lev->U; |
||
583 | return 1; |
||
584 | } |
||
585 | else |
||
586 | return 0; |
||
587 | } |
||
588 | |||
589 | /*-------------------------------------------------------------------*/ |
||
590 | |||
591 | /*** Task functions ***/ |
||
592 | |||
593 | |||
38 | pj | 594 | static int SS_public_create(LEVEL l, PID p, TASK_MODEL *m) |
2 | pj | 595 | { |
596 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
38 | pj | 597 | SOFT_TASK_MODEL *s; |
2 | pj | 598 | |
599 | #ifdef DEBUG |
||
600 | kern_printf("SS_taskcre "); |
||
601 | #endif |
||
602 | |||
38 | pj | 603 | if (m->pclass != SOFT_PCLASS) return -1; |
604 | if (m->level != 0 && m->level != l) return -1; |
||
605 | s = (SOFT_TASK_MODEL *)m; |
||
606 | if (s->periodicity != APERIODIC) return -1; |
||
607 | |||
608 | s = (SOFT_TASK_MODEL *)m; |
||
609 | |||
2 | pj | 610 | if (s->arrivals == SAVE_ARRIVALS) |
611 | lev->nact[p] = 0; |
||
612 | else |
||
613 | lev->nact[p] = -1; |
||
614 | |||
615 | return 0; /* OK, also if the task cannot be guaranteed */ |
||
616 | } |
||
617 | |||
38 | pj | 618 | static void SS_public_dispatch(LEVEL l, PID p, int nostop) |
2 | pj | 619 | { |
620 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
621 | struct timespec ty; |
||
622 | |||
623 | #ifdef DEBUG |
||
624 | kern_printf("SS_tdi "); |
||
625 | #endif |
||
626 | |||
627 | TIMESPEC_ASSIGN(&ty, &schedule_time); |
||
628 | /* set replenish time */ |
||
629 | if(!BACKGROUND_ON) { |
||
630 | if(lev->server_active == SS_SERVER_NOTACTIVE) { |
||
631 | lev->server_active = SS_SERVER_ACTIVE; |
||
632 | ADDUSEC2TIMESPEC(lev->period,&ty); |
||
633 | TIMESPEC_ASSIGN(&lev->lastdline, &ty); |
||
634 | #ifdef DEBUG |
||
635 | kern_printf("tdiPID:%d RT:%d.%d ",p,ty.tv_sec,ty.tv_nsec); |
||
636 | #endif |
||
637 | kern_event_post(&ty, SS_replenish_timer,(void *) l); |
||
638 | } |
||
639 | } |
||
640 | |||
641 | #ifdef DEBUG |
||
642 | if (nostop) kern_printf("NOSTOP!!! "); |
||
643 | #endif |
||
644 | |||
645 | /* there is at least one task ready inserted in an RM or similar level. |
||
646 | Note that we can't check the status because the scheduler sets it |
||
647 | to exe before calling task_dispatch. |
||
648 | We have to check lev->activated != p instead */ |
||
649 | if (lev->activated != p) { |
||
29 | pj | 650 | iq_extract(p, &lev->wait); |
2 | pj | 651 | #ifdef DEBUG |
652 | kern_printf("extr task:%d ",p); |
||
653 | #endif |
||
654 | } |
||
655 | else { |
||
656 | #ifdef DEBUG |
||
657 | if (nostop) kern_printf("(gd status=%d)",proc_table[p].status); |
||
658 | #endif |
||
659 | level_table[lev->scheduling_level]-> |
||
38 | pj | 660 | private_dispatch(lev->scheduling_level,p,nostop); |
2 | pj | 661 | } |
662 | |||
663 | /* set capacity timer */ |
||
664 | if (!nostop && !BACKGROUND_ON) { |
||
665 | TIMESPEC_ASSIGN(&ty, &schedule_time); |
||
666 | // kern_printf("ty:%d.%d ",ty.tv_sec,ty.tv_nsec); |
||
667 | ADDUSEC2TIMESPEC((lev->availCs<=0 ? 0:lev->availCs),&ty); |
||
668 | // kern_printf("avCs:%d ty:%d.%d ",lev->availCs,ty.tv_sec,ty.tv_nsec); |
||
669 | /* stop the task if budget ends */ |
||
670 | #ifdef DEBUG |
||
671 | kern_printf("PID:%d ST=%d.%d ",p,ty.tv_sec,ty.tv_nsec); |
||
672 | #endif |
||
673 | cap_timer = kern_event_post(&ty, SS_capacity_timer,(void *) l); |
||
674 | } |
||
675 | } |
||
676 | |||
38 | pj | 677 | static void SS_public_epilogue(LEVEL l, PID p) { |
2 | pj | 678 | |
679 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
680 | struct timespec ty; |
||
681 | int tx; |
||
682 | |||
683 | #ifdef DEBUG |
||
684 | kern_printf("SS_tep "); |
||
685 | #endif |
||
686 | |||
687 | /* update the server capacity */ |
||
688 | if (BACKGROUND_ON) |
||
689 | lev->flags &= ~SS_BACKGROUND; |
||
690 | else { |
||
691 | SUBTIMESPEC(&schedule_time, &cap_lasttime, &ty); |
||
692 | // kern_printf("ty:%d.%d ",ty.tv_sec,ty.tv_nsec); |
||
693 | tx = TIMESPEC2USEC(&ty); |
||
694 | lev->availCs -= tx; |
||
695 | // kern_printf("avCs:%d ty:%d.%d ",lev->availCs,ty.tv_sec,ty.tv_nsec); |
||
696 | lev->replenish_amount += tx; |
||
697 | #ifdef DEBUG |
||
698 | kern_printf("RA:%d ",lev->replenish_amount); |
||
699 | #endif |
||
700 | } |
||
701 | |||
702 | /* check if the server capacity is finished... */ |
||
703 | if (lev->availCs <= 0) { |
||
704 | /* The server slice has finished... do the task_end!!! |
||
705 | A first version of the module used the task_endcycle, but it was |
||
706 | not conceptually correct because the task didn't stop because it |
||
707 | finished all the work, but because the server didn't have budget! |
||
708 | So, if the task_endcycle is called, the task remain into the |
||
709 | master level, and we can't wake him up if, for example, another |
||
710 | task point the shadow to it!!! */ |
||
711 | |||
712 | /* set replenish amount */ |
||
713 | if(!(BACKGROUND_ON)) { |
||
714 | if(lev->server_active == SS_SERVER_ACTIVE) { |
||
715 | lev->server_active = SS_SERVER_NOTACTIVE; |
||
716 | if(ssq_inslast(l, lev->replenish_amount) == NIL) { |
||
717 | kern_printf("SS: no more space to post replenishment\n"); |
||
718 | kern_printf("You should recompile setting higher SS_MAX_REPLENISH into include/modules/ss.h\n"); |
||
38 | pj | 719 | SS_internal_status(l); |
14 | pj | 720 | kern_raise(XINVALID_SS_REPLENISH,exec_shadow); |
2 | pj | 721 | #ifdef DEBUG |
722 | sys_abort(-1); |
||
723 | exit(-1); |
||
724 | #endif |
||
725 | } |
||
726 | lev->replenish_amount = 0; |
||
727 | } |
||
728 | } |
||
729 | |||
730 | if (lev->activated == p) |
||
38 | pj | 731 | level_table[lev->scheduling_level]->private_extract(lev->scheduling_level,p); |
2 | pj | 732 | |
29 | pj | 733 | iq_insertfirst(p, &lev->wait); |
2 | pj | 734 | proc_table[p].status = SS_WAIT; |
735 | lev->activated = NIL; |
||
736 | } |
||
737 | else { |
||
738 | /* The task has been preempted. |
||
739 | It returns into the ready queue or to the |
||
38 | pj | 740 | wait queue by calling the private_epilogue... */ |
2 | pj | 741 | |
742 | if (lev->activated == p) { /* goes into ready queue */ |
||
743 | level_table[ lev->scheduling_level ]-> |
||
38 | pj | 744 | private_epilogue(lev->scheduling_level,p); |
2 | pj | 745 | } |
746 | else { /* goes into wait queue */ |
||
29 | pj | 747 | iq_insertfirst(p, &lev->wait); |
2 | pj | 748 | proc_table[p].status = SS_WAIT; |
749 | } |
||
750 | } |
||
751 | } |
||
752 | |||
38 | pj | 753 | static void SS_public_activate(LEVEL l, PID p) |
2 | pj | 754 | { |
755 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
756 | struct timespec ty; |
||
757 | |||
758 | #ifdef DEBUG |
||
759 | kern_printf("SS_tacti "); |
||
760 | #endif |
||
761 | |||
762 | if (lev->activated == p || proc_table[p].status == SS_WAIT) { |
||
763 | if (lev->nact[p] != -1) lev->nact[p]++; |
||
764 | } |
||
765 | else if (proc_table[p].status == SLEEP) { |
||
766 | if (lev->activated == NIL && lev->availCs > 0) { |
||
767 | if(!BACKGROUND_ON) { |
||
768 | /* if server is active, replenish time already set */ |
||
769 | if (lev->server_active == SS_SERVER_NOTACTIVE) { |
||
770 | lev->server_active = SS_SERVER_ACTIVE; |
||
771 | /* set replenish time */ |
||
38 | pj | 772 | kern_gettime(&ty); |
2 | pj | 773 | ADDUSEC2TIMESPEC(lev->period, &ty); |
774 | TIMESPEC_ASSIGN(&lev->lastdline, &ty); |
||
775 | #ifdef DEBUG |
||
776 | kern_printf("RT=%d.%d ",ty.tv_sec,ty.tv_nsec); |
||
777 | #endif |
||
778 | kern_event_post(&ty, SS_replenish_timer, (void *) l); |
||
779 | } |
||
780 | } |
||
781 | lev->activated = p; |
||
782 | SS_activation(lev); |
||
783 | } |
||
784 | else { |
||
29 | pj | 785 | iq_insertlast(p, &lev->wait); |
2 | pj | 786 | proc_table[p].status = SS_WAIT; |
787 | } |
||
788 | } |
||
789 | else { |
||
790 | kern_printf("SS_REJ%d %d %d %d ", |
||
791 | p, |
||
792 | proc_table[p].status, |
||
793 | lev->activated, |
||
794 | lev->wait.first); |
||
795 | return; |
||
796 | } |
||
797 | } |
||
798 | |||
38 | pj | 799 | static void SS_public_unblock(LEVEL l, PID p) |
2 | pj | 800 | { |
801 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
802 | |||
803 | #ifdef DEBUG |
||
804 | kern_printf("SS_tins "); |
||
805 | #endif |
||
806 | lev->flags &= ~SS_BACKGROUND_BLOCK; |
||
807 | |||
808 | lev->activated = NIL; |
||
809 | |||
810 | /* when we reinsert the task into the system, the server capacity |
||
811 | is always 0 because nobody executes with the SS before... */ |
||
29 | pj | 812 | iq_insertfirst(p, &lev->wait); |
2 | pj | 813 | proc_table[p].status = SS_WAIT; |
814 | } |
||
815 | |||
38 | pj | 816 | static void SS_public_block(LEVEL l, PID p) |
2 | pj | 817 | { |
818 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
819 | |||
820 | #ifdef DEBUG |
||
821 | kern_printf("SS_textr "); |
||
822 | #endif |
||
823 | |||
824 | /* set replenish amount */ |
||
825 | if(!(BACKGROUND_ON)) { |
||
826 | SS_set_ra(l); |
||
827 | } |
||
828 | |||
829 | /* clear the server capacity */ |
||
830 | lev->availCs = 0; |
||
831 | |||
832 | lev->flags |= SS_BACKGROUND_BLOCK; |
||
833 | |||
834 | if (lev->activated == p) |
||
38 | pj | 835 | level_table[lev->scheduling_level]->private_extract(lev->scheduling_level,p); |
2 | pj | 836 | } |
837 | |||
38 | pj | 838 | static int SS_public_message(LEVEL l, PID p, void *m) |
2 | pj | 839 | { |
840 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
841 | struct timespec ty; |
||
842 | int tx; |
||
843 | |||
844 | #ifdef DEBUG |
||
845 | kern_printf("SS_tendcy "); |
||
846 | #endif |
||
847 | |||
848 | /* update the server capacity */ |
||
849 | if (BACKGROUND_ON) |
||
850 | lev->flags &= ~SS_BACKGROUND; |
||
851 | else { |
||
852 | SUBTIMESPEC(&schedule_time, &cap_lasttime, &ty); |
||
853 | tx = TIMESPEC2USEC(&ty); |
||
854 | lev->availCs -= tx; |
||
855 | lev->replenish_amount += tx; |
||
856 | #ifdef DEBUG |
||
857 | kern_printf("PID:%d RA=%d ",lev->replenish_amount); |
||
858 | #endif |
||
859 | } |
||
860 | |||
861 | if (lev->activated == p) |
||
38 | pj | 862 | level_table[lev->scheduling_level]->private_extract(lev->scheduling_level,p); |
2 | pj | 863 | else |
29 | pj | 864 | iq_extract(p, &lev->wait); |
2 | pj | 865 | |
866 | if (lev->nact[p] > 0) { |
||
867 | lev->nact[p]--; |
||
29 | pj | 868 | iq_insertlast(p, &lev->wait); |
2 | pj | 869 | proc_table[p].status = SS_WAIT; |
870 | } |
||
871 | else { |
||
872 | proc_table[p].status = SLEEP; |
||
873 | } |
||
874 | |||
29 | pj | 875 | lev->activated = iq_getfirst(&lev->wait); |
2 | pj | 876 | if (lev->activated != NIL) { |
877 | SS_activation(lev); |
||
878 | } |
||
879 | else { |
||
880 | /* No more task to schedule; set replenish amount */ |
||
881 | if(!(BACKGROUND_ON)) { |
||
882 | SS_set_ra(l); |
||
883 | } |
||
884 | } |
||
38 | pj | 885 | |
886 | jet_update_endcycle(); /* Update the Jet data... */ |
||
887 | trc_logevent(TRC_ENDCYCLE,&exec_shadow); /* tracer stuff */ |
||
888 | |||
889 | return 0; |
||
2 | pj | 890 | } |
891 | |||
38 | pj | 892 | static void SS_public_end(LEVEL l, PID p) |
2 | pj | 893 | { |
894 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
895 | struct timespec ty; |
||
896 | int tx; |
||
897 | |||
898 | #ifdef DEBUG |
||
899 | kern_printf("SS_tend "); |
||
900 | #endif |
||
901 | |||
902 | /* update the server capacity */ |
||
903 | if (BACKGROUND_ON) |
||
904 | lev->flags &= ~SS_BACKGROUND; |
||
905 | else { |
||
906 | SUBTIMESPEC(&schedule_time, &cap_lasttime, &ty); |
||
907 | tx = TIMESPEC2USEC(&ty); |
||
908 | lev->availCs -= tx; |
||
909 | lev->replenish_amount += tx; |
||
910 | #ifdef DEBUG |
||
911 | kern_printf("PID:%d RA=%d ",p,lev->replenish_amount); |
||
912 | #endif |
||
913 | } |
||
914 | |||
915 | if (lev->activated == p) |
||
38 | pj | 916 | level_table[lev->scheduling_level]->private_extract(lev->scheduling_level,p); |
2 | pj | 917 | |
918 | proc_table[p].status = FREE; |
||
29 | pj | 919 | iq_insertfirst(p,&freedesc); |
2 | pj | 920 | |
29 | pj | 921 | lev->activated = iq_getfirst(&lev->wait); |
2 | pj | 922 | if (lev->activated != NIL) { |
923 | SS_activation(lev); |
||
924 | } |
||
925 | else { |
||
926 | if(!(BACKGROUND_ON)){ |
||
927 | /* No more task to schedule; set replenish amount */ |
||
928 | SS_set_ra(l); |
||
929 | } |
||
930 | } |
||
931 | } |
||
932 | |||
933 | /*-------------------------------------------------------------------*/ |
||
934 | |||
935 | /*** Registration functions ***/ |
||
936 | |||
937 | |||
938 | /*+ Registration function: |
||
939 | int flags the init flags ... see SS.h +*/ |
||
38 | pj | 940 | LEVEL SS_register_level(int flags, LEVEL master, int Cs, int per) |
2 | pj | 941 | { |
942 | LEVEL l; /* the level that we register */ |
||
943 | SS_level_des *lev; /* for readableness only */ |
||
944 | PID i; /* a counter */ |
||
945 | |||
946 | /* request an entry in the level_table */ |
||
38 | pj | 947 | l = level_alloc_descriptor(sizeof(SS_level_des)); |
2 | pj | 948 | |
38 | pj | 949 | lev = (SS_level_des *)level_table[l]; |
2 | pj | 950 | |
38 | pj | 951 | printk(" lev=%d\n",(int)lev); |
2 | pj | 952 | |
953 | /* fill the standard descriptor */ |
||
954 | |||
955 | if (flags & SS_ENABLE_BACKGROUND) |
||
38 | pj | 956 | lev->l.public_scheduler = SS_public_schedulerbackground; |
2 | pj | 957 | |
958 | if (flags & SS_ENABLE_GUARANTEE_EDF) |
||
38 | pj | 959 | lev->l.public_guarantee = SS_public_guaranteeEDF; |
2 | pj | 960 | else if (flags & SS_ENABLE_GUARANTEE_RM) |
38 | pj | 961 | lev->l.public_guarantee = SS_public_guaranteeRM; |
2 | pj | 962 | else |
38 | pj | 963 | lev->l.public_guarantee = NULL; |
2 | pj | 964 | |
38 | pj | 965 | lev->l.public_create = SS_public_create; |
966 | lev->l.public_end = SS_public_end; |
||
967 | lev->l.public_dispatch = SS_public_dispatch; |
||
968 | lev->l.public_epilogue = SS_public_epilogue; |
||
969 | lev->l.public_activate = SS_public_activate; |
||
970 | lev->l.public_unblock = SS_public_unblock; |
||
971 | lev->l.public_block = SS_public_block; |
||
972 | lev->l.public_message = SS_public_message; |
||
2 | pj | 973 | |
974 | /* fill the SS descriptor part */ |
||
975 | |||
976 | for (i=0; i<MAX_PROC; i++) |
||
977 | lev->nact[i] = -1; |
||
978 | |||
979 | lev->Cs = Cs; |
||
980 | lev->availCs = Cs; |
||
981 | |||
982 | lev->period = per; |
||
983 | |||
29 | pj | 984 | iq_init(&lev->wait, &freedesc, 0); |
2 | pj | 985 | lev->activated = NIL; |
986 | |||
987 | lev->U = (MAX_BANDWIDTH / per) * Cs; |
||
988 | |||
989 | lev->scheduling_level = master; |
||
990 | |||
991 | lev->flags = flags & 0x07; |
||
992 | |||
993 | /* This is superfluos. I do it for robustness */ |
||
994 | for (i=0;i<SS_MAX_REPLENISH;lev->replenishment[i++]=0); |
||
995 | |||
996 | /* Initialize replenishment stuff */ |
||
997 | lev->rfirst=0; |
||
998 | lev->rlast=0; |
||
999 | lev->rcount=0; |
||
1000 | lev->replenish_amount=0; |
||
1001 | lev->server_active=SS_SERVER_NOTACTIVE; |
||
38 | pj | 1002 | |
1003 | return l; |
||
2 | pj | 1004 | } |
1005 | |||
1006 | bandwidth_t SS_usedbandwidth(LEVEL l) |
||
1007 | { |
||
1008 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
38 | pj | 1009 | |
1010 | return lev->U; |
||
2 | pj | 1011 | } |
1012 | |||
1013 | int SS_availCs(LEVEL l) { |
||
1014 | SS_level_des *lev = (SS_level_des *)(level_table[l]); |
||
38 | pj | 1015 | |
1016 | return lev->availCs; |
||
2 | pj | 1017 | } |