kernel/ckrm/ckrm_cpu_class.c

   1 /* kernel/ckrm/ckrm_cpu_class.c - CPU Class resource controller for CKRM
   2  *
   3  * Copyright (C) Haoqiang Zheng,  IBM Corp. 2004
   4  *           (C) Hubertus Franke, IBM Corp. 2004
   5  *
   6  * Latest version, more details at http://ckrm.sf.net
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  */
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <asm/errno.h>
  18 #include <linux/sched.h>
  19 #include <linux/ckrm.h>
  20 #include <linux/ckrm_rc.h>
  21 #include <linux/ckrm_tc.h>
  22 #include <linux/ckrm_sched.h>
  23 #include <linux/ckrm_classqueue.h>
  24 #include <linux/seq_file.h>
  25
  26 struct ckrm_res_ctlr cpu_rcbs;
  27
  28 /**
  29  * insert_cpu_class - insert a class to active_cpu_class list
  30  *
  31  * insert the class in decreasing order of class weight
  32  */
  33 static inline void insert_cpu_class(struct ckrm_cpu_class *cls)
  34 {
  35         list_add(&cls->links,&active_cpu_classes);
  36 }
  37
  38 /*
  39  *  initialize a class object and its local queues
  40  */
  41 void init_cpu_class(struct ckrm_cpu_class *cls,ckrm_shares_t* shares)
  42 {
  43         int i,j,k;
  44         prio_array_t *array;
  45         ckrm_lrq_t* queue;
  46
  47         cls->shares = *shares;
  48         cls->cnt_lock = SPIN_LOCK_UNLOCKED;
  49         ckrm_cpu_stat_init(&cls->stat);
  50         ckrm_usage_init(&cls->usage);
  51         cls->magic = CKRM_CPU_CLASS_MAGIC;
  52
  53         for (i = 0 ; i < NR_CPUS ; i++) {
  54                 queue = &cls->local_queues[i];
  55                 queue->active  = queue->arrays;
  56                 queue->expired = queue->arrays+1;
  57
  58                 for (j = 0; j < 2; j++) {
  59                         array = queue->arrays + j;
  60                         for (k = 0; k < MAX_PRIO; k++) {
  61                                 INIT_LIST_HEAD(array->queue + k);
  62                                 __clear_bit(k, array->bitmap);
  63                         }
  64                         // delimiter for bitsearch
  65                         __set_bit(MAX_PRIO, array->bitmap);
  66                         array->nr_active = 0;
  67                 }
  68
  69                 queue->expired_timestamp = 0;
  70
  71                 queue->cpu_class = cls;
  72                 queue->classqueue = get_cpu_classqueue(i);
  73                 queue->top_priority = MAX_PRIO;
  74                 cq_node_init(&queue->classqueue_linkobj);
  75                 queue->local_cvt = 0;
  76                 queue->lrq_load = 0;
  77                 queue->local_weight = cpu_class_weight(cls);
  78                 queue->uncounted_ns = 0;
  79                 queue->savings = 0;
  80                 queue->magic = 0x43FF43D7;
  81         }
  82
  83         // add to class list
  84         write_lock(&class_list_lock);
  85         insert_cpu_class(cls);
  86         write_unlock(&class_list_lock);
  87 }
  88
  89 static inline void set_default_share(ckrm_shares_t *shares)
  90 {
  91         shares->my_guarantee     = 0;
  92         shares->total_guarantee  = CKRM_SHARE_DFLT_TOTAL_GUARANTEE;
  93         shares->unused_guarantee = CKRM_SHARE_DFLT_TOTAL_GUARANTEE;
  94         shares->my_limit         = CKRM_SHARE_DFLT_MAX_LIMIT;
  95         shares->max_limit        = CKRM_SHARE_DFLT_MAX_LIMIT;
  96         shares->cur_max_limit    = 0;
  97 }
  98
  99 struct ckrm_cpu_class * ckrm_get_cpu_class(struct ckrm_core_class *core)
 100 {
 101         struct ckrm_cpu_class * cls;
 102         cls = ckrm_get_res_class(core, cpu_rcbs.resid, struct ckrm_cpu_class);
 103         if (valid_cpu_class(cls))
 104                 return cls;
 105         else
 106                 return NULL;
 107 }
 108
 109
 110 void* ckrm_alloc_cpu_class(struct ckrm_core_class *core, struct ckrm_core_class *parent)
 111 {
 112         struct ckrm_cpu_class *cls;
 113
 114         if (! parent) /*root class*/
 115                 cls =  get_default_cpu_class();
 116         else
 117                 cls = (struct ckrm_cpu_class *) kmalloc(sizeof(struct ckrm_cpu_class),GFP_ATOMIC);
 118
 119         if (cls) {
 120                 ckrm_shares_t shares;
 121                 if ((! parent) && (core)) {
 122                         /*
 123                          * the default class is already initialized
 124                          * so only update the core structure
 125                          */
 126                         cls->core = core;
 127                 } else {
 128                         set_default_share(&shares);
 129                         init_cpu_class(cls,&shares);
 130                         cls->core = core;
 131                         cls->parent = parent;
 132                 }
 133         } else
 134                 printk(KERN_ERR"alloc_cpu_class failed\n");
 135
 136         return cls;
 137 }
 138
 139 /*
 140  * hzheng: this is not a stable implementation
 141  *         need to check race condition issue here
 142  */
 143 static void ckrm_free_cpu_class(void *my_res)
 144 {
 145         struct ckrm_cpu_class *cls = my_res, *parres, *childres;
 146         ckrm_core_class_t *child = NULL;
 147         int maxlimit;
 148
 149         if (!cls)
 150                 return;
 151
 152         /*the default class can't be freed*/
 153         if (cls == get_default_cpu_class())
 154                 return;
 155
 156         // Assuming there will be no children when this function is called
 157         parres = ckrm_get_cpu_class(cls->parent);
 158
 159         // return child's limit/guarantee to parent node
 160         spin_lock(&parres->cnt_lock);
 161         child_guarantee_changed(&parres->shares, cls->shares.my_guarantee, 0);
 162         // run thru parent's children and get the new max_limit of the parent
 163         ckrm_lock_hier(parres->core);
 164         maxlimit = 0;
 165         while ((child = ckrm_get_next_child(parres->core, child)) != NULL) {
 166                 childres = ckrm_get_cpu_class(child);
 167                 if (maxlimit < childres->shares.my_limit) {
 168                         maxlimit = childres->shares.my_limit;
 169                 }
 170         }
 171         ckrm_unlock_hier(parres->core);
 172         if (parres->shares.cur_max_limit < maxlimit) {
 173                 parres->shares.cur_max_limit = maxlimit;
 174         }
 175
 176         spin_unlock(&parres->cnt_lock);
 177
 178         write_lock(&class_list_lock);
 179         list_del(&cls->links);
 180         write_unlock(&class_list_lock);
 181
 182         kfree(cls);
 183 }
 184
 185 /*
 186  *  the system will adjust to the new share automatically
 187  */
 188 int ckrm_cpu_set_share(void *my_res, struct ckrm_shares *new_share)
 189 {
 190         struct ckrm_cpu_class *parres, *cls = my_res;
 191         struct ckrm_shares *cur = &cls->shares, *par;
 192         int rc = -EINVAL;
 193
 194         if (!cls)
 195                 return rc;
 196
 197         if (cls->parent) {
 198                 parres = ckrm_get_cpu_class(cls->parent);
 199                 spin_lock(&parres->cnt_lock);
 200                 spin_lock(&cls->cnt_lock);
 201                 par = &parres->shares;
 202         } else {
 203                 spin_lock(&cls->cnt_lock);
 204                 par = NULL;
 205                 parres = NULL;
 206         }
 207
 208         /*
 209          * hzheng: CKRM_SHARE_DONTCARE should be handled
 210          */
 211         if (new_share->my_guarantee == CKRM_SHARE_DONTCARE)
 212                 new_share->my_guarantee = 0;
 213
 214         rc = set_shares(new_share, cur, par);
 215         if (cur->my_limit == CKRM_SHARE_DONTCARE)
 216                 cur->my_limit = cur->max_limit;
 217
 218
 219         spin_unlock(&cls->cnt_lock);
 220         if (cls->parent) {
 221                 spin_unlock(&parres->cnt_lock);
 222         }
 223         return rc;
 224 }
 225
 226 static int ckrm_cpu_get_share(void *my_res,
 227                               struct ckrm_shares *shares)
 228 {
 229         struct ckrm_cpu_class *cls = my_res;
 230
 231         if (!cls)
 232                 return -EINVAL;
 233         *shares = cls->shares;
 234         return 0;
 235 }
 236
 237 int ckrm_cpu_get_stats(void *my_res, struct seq_file * sfile)
 238 {
 239         struct ckrm_cpu_class *cls = my_res;
 240         struct ckrm_cpu_class_stat* stat = &cls->stat;
 241         ckrm_lrq_t* lrq;
 242         int i;
 243
 244         if (!cls)
 245                 return -EINVAL;
 246
 247         seq_printf(sfile, "-------- CPU Class Status Start---------\n");
 248         seq_printf(sfile, "Share:\n\tgrt= %d limit= %d total_grt= %d max_limit= %d\n",
 249                    cls->shares.my_guarantee,
 250                    cls->shares.my_limit,
 251                    cls->shares.total_guarantee,
 252                    cls->shares.max_limit);
 253         seq_printf(sfile, "\tunused_grt= %d cur_max_limit= %d\n",
 254                    cls->shares.unused_guarantee,
 255                    cls->shares.cur_max_limit);
 256
 257         seq_printf(sfile, "Effective:\n\tegrt= %d\n",stat->egrt);
 258         seq_printf(sfile, "\tmegrt= %d\n",stat->megrt);
 259         seq_printf(sfile, "\tehl= %d\n",stat->ehl);
 260         seq_printf(sfile, "\tmehl= %d\n",stat->mehl);
 261         seq_printf(sfile, "\teshare= %d\n",stat->eshare);
 262         seq_printf(sfile, "\tmeshare= %d\n",cpu_class_weight(cls));
 263         seq_printf(sfile, "\tmax_demand= %lu\n",stat->max_demand);
 264         seq_printf(sfile, "\ttotal_ns= %llu\n",stat->total_ns);
 265         seq_printf(sfile, "\tusage(2,10,60)= %d %d %d\n",
 266                    get_ckrm_usage(cls,2*HZ),
 267                    get_ckrm_usage(cls,10*HZ),
 268                    get_ckrm_usage(cls,60*HZ)
 269                    );
 270         for_each_online_cpu(i) {
 271                 lrq = get_ckrm_lrq(cls,i);
 272                 seq_printf(sfile, "\tlrq %d demand= %lu weight= %d lrq_load= %lu cvt= %llu sav=%lu\n",i,stat->local_stats[i].cpu_demand,local_class_weight(lrq),lrq->lrq_load,lrq->local_cvt,lrq->savings);
 273         }
 274
 275         seq_printf(sfile, "-------- CPU Class Status END ---------\n");
 276
 277         return 0;
 278 }
 279
 280 /*
 281  * task will remain in the same cpu but on a different local runqueue
 282  */
 283 void ckrm_cpu_change_class(void *task, void *old, void *new)
 284 {
 285         struct task_struct *tsk = task;
 286         struct ckrm_cpu_class *newcls = new;
 287
 288         /*sanity checking*/
 289         if (!task || ! old || !new)
 290                 return;
 291
 292         _ckrm_cpu_change_class(tsk,newcls);
 293 }
 294
 295 /*dummy function, not used*/
 296 static int ckrm_cpu_show_config(void *my_res, struct seq_file *sfile)
 297 {
 298         struct ckrm_cpu_class *cls = my_res;
 299
 300         if (!cls)
 301                 return -EINVAL;
 302
 303         seq_printf(sfile, "cls=%s,parameter=somevalue\n","ckrm_cpu class");
 304         return 0;
 305 }
 306
 307 /*dummy function, not used*/
 308 static int ckrm_cpu_set_config(void *my_res, const char *cfgstr)
 309 {
 310         struct ckrm_cpu_class *cls = my_res;
 311
 312         if (!cls)
 313                 return -EINVAL;
 314         printk("ckrm_cpu config='%s'\n",cfgstr);
 315         return 0;
 316 }
 317
 318 struct ckrm_res_ctlr cpu_rcbs = {
 319         .res_name          = "cpu",
 320         .res_hdepth        = 1,
 321         .resid             = -1,
 322         .res_alloc         = ckrm_alloc_cpu_class,
 323         .res_free          = ckrm_free_cpu_class,
 324         .set_share_values  = ckrm_cpu_set_share,
 325         .get_share_values  = ckrm_cpu_get_share,
 326         .get_stats         = ckrm_cpu_get_stats,
 327         .show_config       = ckrm_cpu_show_config,
 328         .set_config        = ckrm_cpu_set_config,
 329         .change_resclass   = ckrm_cpu_change_class,
 330 };
 331
 332 int __init init_ckrm_sched_res(void)
 333 {
 334         struct ckrm_classtype *clstype;
 335         int resid = cpu_rcbs.resid;
 336
 337         clstype = ckrm_find_classtype_by_name("taskclass");
 338         if (clstype == NULL) {
 339                 printk(KERN_INFO" Unknown ckrm classtype<taskclass>");
 340                 return -ENOENT;
 341         }
 342
 343         if (resid == -1) { /*not registered */
 344                 resid = ckrm_register_res_ctlr(clstype,&cpu_rcbs);
 345                 printk("........init_ckrm_sched_res , resid= %d\n",resid);
 346         }
 347         return 0;
 348 }
 349
 350 /*
 351  * initialize the class structure
 352  * add the default class: class 0
 353  */
 354 void init_cpu_classes(void)
 355 {
 356         int i;
 357
 358         //init classqueues for each processor
 359         for (i=0; i < NR_CPUS; i++)
 360                 classqueue_init(get_cpu_classqueue(i));
 361
 362         /*
 363          * hzheng: initialize the default cpu class
 364          *  required for E14/E15 since ckrm_init is called after sched_init
 365          */
 366         ckrm_alloc_cpu_class(NULL,NULL);
 367 }
 368
 369
 370 EXPORT_SYMBOL(ckrm_get_cpu_class);