arch/s390/appldata/appldata_base.c

   1 /*
   2  * arch/s390/appldata/appldata_base.c
   3  *
   4  * Base infrastructure for Linux-z/VM Monitor Stream, Stage 1.
   5  * Exports appldata_register_ops() and appldata_unregister_ops() for the
   6  * data gathering modules.
   7  *
   8  * Copyright IBM Corp. 2003, 2008
   9  *
  10  * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
  11  */
  12
  13 #define KMSG_COMPONENT  "appldata"
  14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  15
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/slab.h>
  19 #include <linux/errno.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/pagemap.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/notifier.h>
  27 #include <linux/cpu.h>
  28 #include <linux/workqueue.h>
  29 #include <asm/appldata.h>
  30 #include <asm/timer.h>
  31 #include <asm/uaccess.h>
  32 #include <asm/io.h>
  33 #include <asm/smp.h>
  34
  35 #include "appldata.h"
  36
  37
  38 #define APPLDATA_CPU_INTERVAL   10000           /* default (CPU) time for
  39                                                    sampling interval in
  40                                                    milliseconds */
  41
  42 #define TOD_MICRO       0x01000                 /* nr. of TOD clock units
  43                                                    for 1 microsecond */
  44 /*
  45  * /proc entries (sysctl)
  46  */
  47 static const char appldata_proc_name[APPLDATA_PROC_NAME_LENGTH] = "appldata";
  48 static int appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
  49                                   void __user *buffer, size_t *lenp, loff_t *ppos);
  50 static int appldata_interval_handler(ctl_table *ctl, int write,
  51                                          struct file *filp,
  52                                          void __user *buffer,
  53                                          size_t *lenp, loff_t *ppos);
  54
  55 static struct ctl_table_header *appldata_sysctl_header;
  56 static struct ctl_table appldata_table[] = {
  57         {
  58                 .procname       = "timer",
  59                 .mode           = S_IRUGO | S_IWUSR,
  60                 .proc_handler   = &appldata_timer_handler,
  61         },
  62         {
  63                 .procname       = "interval",
  64                 .mode           = S_IRUGO | S_IWUSR,
  65                 .proc_handler   = &appldata_interval_handler,
  66         },
  67         { },
  68 };
  69
  70 static struct ctl_table appldata_dir_table[] = {
  71         {
  72                 .procname       = appldata_proc_name,
  73                 .maxlen         = 0,
  74                 .mode           = S_IRUGO | S_IXUGO,
  75                 .child          = appldata_table,
  76         },
  77         { },
  78 };
  79
  80 /*
  81  * Timer
  82  */
  83 static DEFINE_PER_CPU(struct vtimer_list, appldata_timer);
  84 static atomic_t appldata_expire_count = ATOMIC_INIT(0);
  85
  86 static DEFINE_SPINLOCK(appldata_timer_lock);
  87 static int appldata_interval = APPLDATA_CPU_INTERVAL;
  88 static int appldata_timer_active;
  89
  90 /*
  91  * Work queue
  92  */
  93 static struct workqueue_struct *appldata_wq;
  94 static void appldata_work_fn(struct work_struct *work);
  95 static DECLARE_WORK(appldata_work, appldata_work_fn);
  96
  97
  98 /*
  99  * Ops list
 100  */
 101 static DEFINE_SPINLOCK(appldata_ops_lock);
 102 static LIST_HEAD(appldata_ops_list);
 103
 104
 105 /*************************** timer, work, DIAG *******************************/
 106 /*
 107  * appldata_timer_function()
 108  *
 109  * schedule work and reschedule timer
 110  */
 111 static void appldata_timer_function(unsigned long data)
 112 {
 113         if (atomic_dec_and_test(&appldata_expire_count)) {
 114                 atomic_set(&appldata_expire_count, num_online_cpus());
 115                 queue_work(appldata_wq, (struct work_struct *) data);
 116         }
 117 }
 118
 119 /*
 120  * appldata_work_fn()
 121  *
 122  * call data gathering function for each (active) module
 123  */
 124 static void appldata_work_fn(struct work_struct *work)
 125 {
 126         struct list_head *lh;
 127         struct appldata_ops *ops;
 128         int i;
 129
 130         i = 0;
 131         get_online_cpus();
 132         spin_lock(&appldata_ops_lock);
 133         list_for_each(lh, &appldata_ops_list) {
 134                 ops = list_entry(lh, struct appldata_ops, list);
 135                 if (ops->active == 1) {
 136                         ops->callback(ops->data);
 137                 }
 138         }
 139         spin_unlock(&appldata_ops_lock);
 140         put_online_cpus();
 141 }
 142
 143 /*
 144  * appldata_diag()
 145  *
 146  * prepare parameter list, issue DIAG 0xDC
 147  */
 148 int appldata_diag(char record_nr, u16 function, unsigned long buffer,
 149                         u16 length, char *mod_lvl)
 150 {
 151         struct appldata_product_id id = {
 152                 .prod_nr    = {0xD3, 0xC9, 0xD5, 0xE4,
 153                                0xE7, 0xD2, 0xD9},       /* "LINUXKR" */
 154                 .prod_fn    = 0xD5D3,                   /* "NL" */
 155                 .version_nr = 0xF2F6,                   /* "26" */
 156                 .release_nr = 0xF0F1,                   /* "01" */
 157         };
 158
 159         id.record_nr = record_nr;
 160         id.mod_lvl = (mod_lvl[0]) << 8 | mod_lvl[1];
 161         return appldata_asm(&id, function, (void *) buffer, length);
 162 }
 163 /************************ timer, work, DIAG <END> ****************************/
 164
 165
 166 /****************************** /proc stuff **********************************/
 167
 168 /*
 169  * appldata_mod_vtimer_wrap()
 170  *
 171  * wrapper function for mod_virt_timer(), because smp_call_function_single()
 172  * accepts only one parameter.
 173  */
 174 static void __appldata_mod_vtimer_wrap(void *p) {
 175         struct {
 176                 struct vtimer_list *timer;
 177                 u64    expires;
 178         } *args = p;
 179         mod_virt_timer(args->timer, args->expires);
 180 }
 181
 182 #define APPLDATA_ADD_TIMER      0
 183 #define APPLDATA_DEL_TIMER      1
 184 #define APPLDATA_MOD_TIMER      2
 185
 186 /*
 187  * __appldata_vtimer_setup()
 188  *
 189  * Add, delete or modify virtual timers on all online cpus.
 190  * The caller needs to get the appldata_timer_lock spinlock.
 191  */
 192 static void
 193 __appldata_vtimer_setup(int cmd)
 194 {
 195         u64 per_cpu_interval;
 196         int i;
 197
 198         switch (cmd) {
 199         case APPLDATA_ADD_TIMER:
 200                 if (appldata_timer_active)
 201                         break;
 202                 per_cpu_interval = (u64) (appldata_interval*1000 /
 203                                           num_online_cpus()) * TOD_MICRO;
 204                 for_each_online_cpu(i) {
 205                         per_cpu(appldata_timer, i).expires = per_cpu_interval;
 206                         smp_call_function_single(i, add_virt_timer_periodic,
 207                                                  &per_cpu(appldata_timer, i),
 208                                                  1);
 209                 }
 210                 appldata_timer_active = 1;
 211                 break;
 212         case APPLDATA_DEL_TIMER:
 213                 for_each_online_cpu(i)
 214                         del_virt_timer(&per_cpu(appldata_timer, i));
 215                 if (!appldata_timer_active)
 216                         break;
 217                 appldata_timer_active = 0;
 218                 atomic_set(&appldata_expire_count, num_online_cpus());
 219                 break;
 220         case APPLDATA_MOD_TIMER:
 221                 per_cpu_interval = (u64) (appldata_interval*1000 /
 222                                           num_online_cpus()) * TOD_MICRO;
 223                 if (!appldata_timer_active)
 224                         break;
 225                 for_each_online_cpu(i) {
 226                         struct {
 227                                 struct vtimer_list *timer;
 228                                 u64    expires;
 229                         } args;
 230                         args.timer = &per_cpu(appldata_timer, i);
 231                         args.expires = per_cpu_interval;
 232                         smp_call_function_single(i, __appldata_mod_vtimer_wrap,
 233                                                  &args, 1);
 234                 }
 235         }
 236 }
 237
 238 /*
 239  * appldata_timer_handler()
 240  *
 241  * Start/Stop timer, show status of timer (0 = not active, 1 = active)
 242  */
 243 static int
 244 appldata_timer_handler(ctl_table *ctl, int write, struct file *filp,
 245                            void __user *buffer, size_t *lenp, loff_t *ppos)
 246 {
 247         int len;
 248         char buf[2];
 249
 250         if (!*lenp || *ppos) {
 251                 *lenp = 0;
 252                 return 0;
 253         }
 254         if (!write) {
 255                 len = sprintf(buf, appldata_timer_active ? "1\n" : "0\n");
 256                 if (len > *lenp)
 257                         len = *lenp;
 258                 if (copy_to_user(buffer, buf, len))
 259                         return -EFAULT;
 260                 goto out;
 261         }
 262         len = *lenp;
 263         if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len))
 264                 return -EFAULT;
 265         get_online_cpus();
 266         spin_lock(&appldata_timer_lock);
 267         if (buf[0] == '1')
 268                 __appldata_vtimer_setup(APPLDATA_ADD_TIMER);
 269         else if (buf[0] == '0')
 270                 __appldata_vtimer_setup(APPLDATA_DEL_TIMER);
 271         spin_unlock(&appldata_timer_lock);
 272         put_online_cpus();
 273 out:
 274         *lenp = len;
 275         *ppos += len;
 276         return 0;
 277 }
 278
 279 /*
 280  * appldata_interval_handler()
 281  *
 282  * Set (CPU) timer interval for collection of data (in milliseconds), show
 283  * current timer interval.
 284  */
 285 static int
 286 appldata_interval_handler(ctl_table *ctl, int write, struct file *filp,
 287                            void __user *buffer, size_t *lenp, loff_t *ppos)
 288 {
 289         int len, interval;
 290         char buf[16];
 291
 292         if (!*lenp || *ppos) {
 293                 *lenp = 0;
 294                 return 0;
 295         }
 296         if (!write) {
 297                 len = sprintf(buf, "%i\n", appldata_interval);
 298                 if (len > *lenp)
 299                         len = *lenp;
 300                 if (copy_to_user(buffer, buf, len))
 301                         return -EFAULT;
 302                 goto out;
 303         }
 304         len = *lenp;
 305         if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len)) {
 306                 return -EFAULT;
 307         }
 308         interval = 0;
 309         sscanf(buf, "%i", &interval);
 310         if (interval <= 0)
 311                 return -EINVAL;
 312
 313         get_online_cpus();
 314         spin_lock(&appldata_timer_lock);
 315         appldata_interval = interval;
 316         __appldata_vtimer_setup(APPLDATA_MOD_TIMER);
 317         spin_unlock(&appldata_timer_lock);
 318         put_online_cpus();
 319 out:
 320         *lenp = len;
 321         *ppos += len;
 322         return 0;
 323 }
 324
 325 /*
 326  * appldata_generic_handler()
 327  *
 328  * Generic start/stop monitoring and DIAG, show status of
 329  * monitoring (0 = not in process, 1 = in process)
 330  */
 331 static int
 332 appldata_generic_handler(ctl_table *ctl, int write, struct file *filp,
 333                            void __user *buffer, size_t *lenp, loff_t *ppos)
 334 {
 335         struct appldata_ops *ops = NULL, *tmp_ops;
 336         int rc, len, found;
 337         char buf[2];
 338         struct list_head *lh;
 339
 340         found = 0;
 341         spin_lock(&appldata_ops_lock);
 342         list_for_each(lh, &appldata_ops_list) {
 343                 tmp_ops = list_entry(lh, struct appldata_ops, list);
 344                 if (&tmp_ops->ctl_table[2] == ctl) {
 345                         found = 1;
 346                 }
 347         }
 348         if (!found) {
 349                 spin_unlock(&appldata_ops_lock);
 350                 return -ENODEV;
 351         }
 352         ops = ctl->data;
 353         if (!try_module_get(ops->owner)) {      // protect this function
 354                 spin_unlock(&appldata_ops_lock);
 355                 return -ENODEV;
 356         }
 357         spin_unlock(&appldata_ops_lock);
 358
 359         if (!*lenp || *ppos) {
 360                 *lenp = 0;
 361                 module_put(ops->owner);
 362                 return 0;
 363         }
 364         if (!write) {
 365                 len = sprintf(buf, ops->active ? "1\n" : "0\n");
 366                 if (len > *lenp)
 367                         len = *lenp;
 368                 if (copy_to_user(buffer, buf, len)) {
 369                         module_put(ops->owner);
 370                         return -EFAULT;
 371                 }
 372                 goto out;
 373         }
 374         len = *lenp;
 375         if (copy_from_user(buf, buffer,
 376                            len > sizeof(buf) ? sizeof(buf) : len)) {
 377                 module_put(ops->owner);
 378                 return -EFAULT;
 379         }
 380
 381         spin_lock(&appldata_ops_lock);
 382         if ((buf[0] == '1') && (ops->active == 0)) {
 383                 // protect work queue callback
 384                 if (!try_module_get(ops->owner)) {
 385                         spin_unlock(&appldata_ops_lock);
 386                         module_put(ops->owner);
 387                         return -ENODEV;
 388                 }
 389                 ops->callback(ops->data);       // init record
 390                 rc = appldata_diag(ops->record_nr,
 391                                         APPLDATA_START_INTERVAL_REC,
 392                                         (unsigned long) ops->data, ops->size,
 393                                         ops->mod_lvl);
 394                 if (rc != 0) {
 395                         pr_err("Starting the data collection for %s "
 396                                "failed with rc=%d\n", ops->name, rc);
 397                         module_put(ops->owner);
 398                 } else
 399                         ops->active = 1;
 400         } else if ((buf[0] == '0') && (ops->active == 1)) {
 401                 ops->active = 0;
 402                 rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
 403                                 (unsigned long) ops->data, ops->size,
 404                                 ops->mod_lvl);
 405                 if (rc != 0)
 406                         pr_err("Stopping the data collection for %s "
 407                                "failed with rc=%d\n", ops->name, rc);
 408                 module_put(ops->owner);
 409         }
 410         spin_unlock(&appldata_ops_lock);
 411 out:
 412         *lenp = len;
 413         *ppos += len;
 414         module_put(ops->owner);
 415         return 0;
 416 }
 417
 418 /*************************** /proc stuff <END> *******************************/
 419
 420
 421 /************************* module-ops management *****************************/
 422 /*
 423  * appldata_register_ops()
 424  *
 425  * update ops list, register /proc/sys entries
 426  */
 427 int appldata_register_ops(struct appldata_ops *ops)
 428 {
 429         if (ops->size > APPLDATA_MAX_REC_SIZE)
 430                 return -EINVAL;
 431
 432         ops->ctl_table = kzalloc(4 * sizeof(struct ctl_table), GFP_KERNEL);
 433         if (!ops->ctl_table)
 434                 return -ENOMEM;
 435
 436         spin_lock(&appldata_ops_lock);
 437         list_add(&ops->list, &appldata_ops_list);
 438         spin_unlock(&appldata_ops_lock);
 439
 440         ops->ctl_table[0].procname = appldata_proc_name;
 441         ops->ctl_table[0].maxlen   = 0;
 442         ops->ctl_table[0].mode     = S_IRUGO | S_IXUGO;
 443         ops->ctl_table[0].child    = &ops->ctl_table[2];
 444
 445         ops->ctl_table[2].procname = ops->name;
 446         ops->ctl_table[2].mode     = S_IRUGO | S_IWUSR;
 447         ops->ctl_table[2].proc_handler = appldata_generic_handler;
 448         ops->ctl_table[2].data = ops;
 449
 450         ops->sysctl_header = register_sysctl_table(ops->ctl_table);
 451         if (!ops->sysctl_header)
 452                 goto out;
 453         return 0;
 454 out:
 455         spin_lock(&appldata_ops_lock);
 456         list_del(&ops->list);
 457         spin_unlock(&appldata_ops_lock);
 458         kfree(ops->ctl_table);
 459         return -ENOMEM;
 460 }
 461
 462 /*
 463  * appldata_unregister_ops()
 464  *
 465  * update ops list, unregister /proc entries, stop DIAG if necessary
 466  */
 467 void appldata_unregister_ops(struct appldata_ops *ops)
 468 {
 469         spin_lock(&appldata_ops_lock);
 470         list_del(&ops->list);
 471         spin_unlock(&appldata_ops_lock);
 472         unregister_sysctl_table(ops->sysctl_header);
 473         kfree(ops->ctl_table);
 474 }
 475 /********************** module-ops management <END> **************************/
 476
 477
 478 /******************************* init / exit *********************************/
 479
 480 static void __cpuinit appldata_online_cpu(int cpu)
 481 {
 482         init_virt_timer(&per_cpu(appldata_timer, cpu));
 483         per_cpu(appldata_timer, cpu).function = appldata_timer_function;
 484         per_cpu(appldata_timer, cpu).data = (unsigned long)
 485                 &appldata_work;
 486         atomic_inc(&appldata_expire_count);
 487         spin_lock(&appldata_timer_lock);
 488         __appldata_vtimer_setup(APPLDATA_MOD_TIMER);
 489         spin_unlock(&appldata_timer_lock);
 490 }
 491
 492 static void __cpuinit appldata_offline_cpu(int cpu)
 493 {
 494         del_virt_timer(&per_cpu(appldata_timer, cpu));
 495         if (atomic_dec_and_test(&appldata_expire_count)) {
 496                 atomic_set(&appldata_expire_count, num_online_cpus());
 497                 queue_work(appldata_wq, &appldata_work);
 498         }
 499         spin_lock(&appldata_timer_lock);
 500         __appldata_vtimer_setup(APPLDATA_MOD_TIMER);
 501         spin_unlock(&appldata_timer_lock);
 502 }
 503
 504 static int __cpuinit appldata_cpu_notify(struct notifier_block *self,
 505                                          unsigned long action,
 506                                          void *hcpu)
 507 {
 508         switch (action) {
 509         case CPU_ONLINE:
 510         case CPU_ONLINE_FROZEN:
 511                 appldata_online_cpu((long) hcpu);
 512                 break;
 513         case CPU_DEAD:
 514         case CPU_DEAD_FROZEN:
 515                 appldata_offline_cpu((long) hcpu);
 516                 break;
 517         default:
 518                 break;
 519         }
 520         return NOTIFY_OK;
 521 }
 522
 523 static struct notifier_block __cpuinitdata appldata_nb = {
 524         .notifier_call = appldata_cpu_notify,
 525 };
 526
 527 /*
 528  * appldata_init()
 529  *
 530  * init timer, register /proc entries
 531  */
 532 static int __init appldata_init(void)
 533 {
 534         int i;
 535
 536         appldata_wq = create_singlethread_workqueue("appldata");
 537         if (!appldata_wq)
 538                 return -ENOMEM;
 539
 540         get_online_cpus();
 541         for_each_online_cpu(i)
 542                 appldata_online_cpu(i);
 543         put_online_cpus();
 544
 545         /* Register cpu hotplug notifier */
 546         register_hotcpu_notifier(&appldata_nb);
 547
 548         appldata_sysctl_header = register_sysctl_table(appldata_dir_table);
 549         return 0;
 550 }
 551
 552 __initcall(appldata_init);
 553
 554 /**************************** init / exit <END> ******************************/
 555
 556 EXPORT_SYMBOL_GPL(appldata_register_ops);
 557 EXPORT_SYMBOL_GPL(appldata_unregister_ops);
 558 EXPORT_SYMBOL_GPL(appldata_diag);
 559
 560 #ifdef CONFIG_SWAP
 561 EXPORT_SYMBOL_GPL(si_swapinfo);
 562 #endif
 563 EXPORT_SYMBOL_GPL(nr_threads);
 564 EXPORT_SYMBOL_GPL(nr_running);
 565 EXPORT_SYMBOL_GPL(nr_iowait);