osfmk/kperf/pet.c

   1 /*
   2  * Copyright (c) 2011 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 /* all thread states code */
  30 #include <mach/mach_types.h>
  31 #include <IOKit/IOTypes.h>
  32 #include <IOKit/IOLocks.h>
  33 #include <sys/errno.h>
  34
  35 #include <chud/chud_xnu.h>
  36
  37 #include <kperf/buffer.h>
  38 #include <kperf/sample.h>
  39 #include <kperf/context.h>
  40 #include <kperf/action.h>
  41 #include <kperf/filter.h>
  42 #include <kperf/pet.h>
  43 #include <kperf/timetrigger.h>
  44
  45 /* timer id to call back on */
  46 static unsigned pet_timerid = 0;
  47
  48 /* aciton ID to call
  49  * We also use this as the sync point for waiting, for no good reason
  50  */
  51 static unsigned pet_actionid = 0;
  52
  53 /* the actual thread pointer */
  54 static thread_t pet_thread = NULL;
  55
  56 /* Lock on which to synchronise */
  57 static IOLock *pet_lock = NULL;
  58
  59 /* where to sample data to */
  60 static struct kperf_sample pet_sample_buf;
  61
  62 /* sample an actual, honest to god thread! */
  63 static void
  64 pet_sample_thread( thread_t thread )
  65 {
  66         struct kperf_context ctx;
  67         task_t task;
  68
  69         /* work out the context */
  70         ctx.cur_thread = thread;
  71         ctx.cur_pid = -1;
  72
  73         task = chudxnu_task_for_thread(thread);
  74         if(task)
  75                 ctx.cur_pid = chudxnu_pid_for_task(task);
  76
  77         /* do the actual sample */
  78         kperf_sample( &pet_sample_buf, &ctx, pet_actionid, false );
  79 }
  80
  81 /* given a list of threads, preferably stopped, sample 'em! */
  82 static void
  83 pet_sample_thread_list( mach_msg_type_number_t threadc, thread_array_t threadv )
  84 {
  85         unsigned int i;
  86
  87         for( i = 0; i < threadc; i++ )
  88         {
  89                 thread_t thread = threadv[i];
  90
  91                 if( !thread )
  92                         /* XXX? */
  93                         continue;
  94
  95                 pet_sample_thread( thread );
  96         }
  97 }
  98
  99 /* given a task (preferably stopped), sample all the threads in it */
 100 static void
 101 pet_sample_task( task_t task )
 102 {
 103         mach_msg_type_number_t threadc;
 104         thread_array_t threadv;
 105         kern_return_t kr;
 106
 107         kr = chudxnu_task_threads(task, &threadv, &threadc);
 108         if( kr != KERN_SUCCESS )
 109         {
 110                 BUF_INFO2(PERF_PET_ERROR, ERR_THREAD, kr);
 111                 return;
 112         }
 113
 114         pet_sample_thread_list( threadc, threadv );
 115
 116         chudxnu_free_thread_list(&threadv, &threadc);
 117 }
 118
 119 /* given a list of tasks, sample all the threads in 'em */
 120 static void
 121 pet_sample_task_list( int taskc, task_array_t taskv  )
 122 {
 123         int i;
 124
 125         for( i = 0; i < taskc; i++ )
 126         {
 127                 kern_return_t kr;
 128                 task_t task = taskv[i];
 129
 130                 /* FIXME: necessary? old code did this, our hacky
 131                  * filtering code does, too
 132                  */
 133                 if(!task) {
 134                         continue;
 135                 }
 136
 137                 /* try and stop any task other than the kernel task */
 138                 if( task != kernel_task )
 139                 {
 140                         kr = task_suspend( task );
 141
 142                         /* try the next task */
 143                         if( kr != KERN_SUCCESS )
 144                                 continue;
 145                 }
 146
 147                 /* sample it */
 148                 pet_sample_task( task );
 149
 150                 /* if it wasn't the kernel, resume it */
 151                 if( task != kernel_task )
 152                         task_resume(task);
 153         }
 154 }
 155
 156 static void
 157 pet_sample_all_tasks(void)
 158 {
 159         task_array_t taskv = NULL;
 160         mach_msg_type_number_t taskc = 0;
 161         kern_return_t kr;
 162
 163         kr = chudxnu_all_tasks(&taskv, &taskc);
 164
 165         if( kr != KERN_SUCCESS )
 166         {
 167                 BUF_INFO2(PERF_PET_ERROR, ERR_TASK, kr);
 168                 return;
 169         }
 170
 171         pet_sample_task_list( taskc, taskv );
 172         chudxnu_free_task_list(&taskv, &taskc);
 173 }
 174
 175 static void
 176 pet_sample_pid_filter(void)
 177 {
 178         task_t *taskv = NULL;
 179         int *pidv, pidc, i;
 180         vm_size_t asize;
 181
 182         kperf_filter_pid_list( &pidc, &pidv );
 183         if( pidc == 0  )
 184         {
 185                 BUF_INFO2(PERF_PET_ERROR, ERR_PID, 0);
 186                 return;
 187         }
 188
 189         asize = pidc * sizeof(task_t);
 190         taskv = kalloc( asize );
 191
 192         if( taskv == NULL )
 193                 goto out;
 194
 195         /* convert the pid list into a task list */
 196         for( i = 0; i < pidc; i++ )
 197         {
 198                 int pid = pidv[i];
 199                 if( pid == -1 )
 200                         taskv[i] = NULL;
 201                 else
 202                         taskv[i] = chudxnu_task_for_pid(pid);
 203         }
 204
 205         /* now sample the task list */
 206         pet_sample_task_list( pidc, taskv );
 207
 208         kfree(taskv, asize);
 209
 210 out:
 211         kperf_filter_free_pid_list( &pidc, &pidv );
 212 }
 213
 214 /* do the pet sample */
 215 static void
 216 pet_work_unit(void)
 217 {
 218         int pid_filter;
 219
 220         /* check if we're filtering on pid  */
 221         pid_filter = kperf_filter_on_pid();
 222
 223         if( pid_filter )
 224         {
 225                 BUF_INFO1(PERF_PET_SAMPLE | DBG_FUNC_START, 1);
 226                 pet_sample_pid_filter();
 227         }
 228         else
 229         {
 230                 /* otherwise filter everything */
 231                 BUF_INFO1(PERF_PET_SAMPLE | DBG_FUNC_START, 0);
 232                 pet_sample_all_tasks();
 233         }
 234
 235         BUF_INFO1(PERF_PET_SAMPLE | DBG_FUNC_END, 0);
 236
 237 }
 238
 239 /* sleep indefinitely */
 240 static void
 241 pet_idle(void)
 242 {
 243         IOLockLock(pet_lock);
 244         IOLockSleep(pet_lock, &pet_actionid, THREAD_UNINT);
 245         IOLockUnlock(pet_lock);
 246 }
 247
 248 /* loop between sampling and waiting */
 249 static void
 250 pet_thread_loop( __unused void *param, __unused wait_result_t wr )
 251 {
 252         BUF_INFO1(PERF_PET_THREAD, 1);
 253
 254         while(1)
 255         {
 256                 BUF_INFO1(PERF_PET_IDLE, 0);
 257                 pet_idle();
 258
 259                 BUF_INFO1(PERF_PET_RUN, 0);
 260                 pet_work_unit();
 261
 262                 /* re-program the timer */
 263                 kperf_timer_pet_set( pet_timerid );
 264
 265                 /* FIXME: break here on a condition? */
 266         }
 267 }
 268
 269 /* make sure the thread takes a new period value */
 270 void
 271 kperf_pet_timer_config( unsigned timerid, unsigned actionid )
 272 {
 273         /* hold the lock so pet thread doesn't run while we do this */
 274         IOLockLock(pet_lock);
 275
 276         BUF_INFO1(PERF_PET_THREAD, 3);
 277
 278         /* set values */
 279         pet_timerid = timerid;
 280         pet_actionid = actionid;
 281
 282         /* done */
 283         IOLockUnlock(pet_lock);
 284 }
 285
 286 /* make the thread run! */
 287 void
 288 kperf_pet_thread_go(void)
 289 {
 290         /* Make the thread go */
 291         IOLockWakeup(pet_lock, &pet_actionid, FALSE);
 292 }
 293
 294
 295 /* wait for the pet thread to finish a run */
 296 void
 297 kperf_pet_thread_wait(void)
 298 {
 299         /* acquire the lock to ensure the thread is parked. */
 300         IOLockLock(pet_lock);
 301         IOLockUnlock(pet_lock);
 302 }
 303
 304 /* keep the pet thread around while we run */
 305 int
 306 kperf_pet_init(void)
 307 {
 308         kern_return_t rc;
 309         thread_t t;
 310
 311         if( pet_thread != NULL )
 312                 return 0;
 313
 314         /* make the sync poing */
 315         pet_lock = IOLockAlloc();
 316         if( pet_lock == NULL )
 317                 return ENOMEM;
 318
 319         /* create the thread */
 320         BUF_INFO1(PERF_PET_THREAD, 0);
 321         rc = kernel_thread_start( pet_thread_loop, NULL, &t );
 322         if( rc != KERN_SUCCESS )
 323         {
 324                 IOLockFree( pet_lock );
 325                 pet_lock = NULL;
 326                 return ENOMEM;
 327         }
 328
 329         /* OK! */
 330         return 0;
 331 }