firmware/profile.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Profiling routines counts ticks and calls to each profiled function.
  11  *
  12  * Copyright (C) 2005 by Brandon Low
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  20  * KIND, either express or implied.
  21  *
  22  ****************************************************************************
  23  *
  24  * profile_func_enter() based on mcount found in gmon.c:
  25  *
  26  ***************************************************************************
  27  * Copyright (c) 1991, 1998 The Regents of the University of California.
  28  * All rights reserved.
  29  *
  30  * Redistribution and use in source and binary forms, with or without
  31  * modification, are permitted provided that the following conditions
  32  * are met:
  33  * 1. Redistributions of source code must retain the above copyright
  34  *    notice, this list of conditions and the following disclaimer.
  35  * 2. Redistributions in binary form must reproduce the above copyright
  36  *    notice, this list of conditions and the following disclaimer in the
  37  *    documentation and/or other materials provided with the distribution.
  38  * 3. [rescinded 22 July 1999]
  39  * 4. Neither the name of the University nor the names of its contributors
  40  *    may be used to endorse or promote products derived from this software
  41  *    without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  * @(#)gmon.c 5.3 (Berkeley) 5/22/91
  55  */
  56
  57 #include <file.h>
  58 #include <sprintf.h>
  59 #include <system.h>
  60 #include <string.h>
  61 #include <timer.h>
  62 #include <sys/types.h>
  63 #include "profile.h"
  64
  65 /* PFD is Profiled Function Data */
  66
  67 /* Indices are shorts which means that we use 4k of RAM */
  68 #define INDEX_BITS 11    /* What is a reasonable size for this? */
  69 #define INDEX_SIZE 2048  /* 2 ^ INDEX_BITS */
  70 #define INDEX_MASK 0x7FF /* lower INDEX_BITS 1 */
  71
  72 /*
  73  * In the current setup (pfd has 4 longs and 2 shorts) this uses 20k of RAM
  74  * for profiling, and allows for profiling sections of code with up-to
  75  * 1024 function caller->callee pairs
  76  */
  77 #define NUMPFDS 512
  78
  79 struct pfd_struct {
  80     void *self_pc;
  81     unsigned long count;
  82     unsigned long time;
  83     unsigned short link;
  84     struct pfd_struct *caller;
  85 };
  86
  87 /* Possible states of profiling */
  88 #define PROF_ON 0x00
  89 #define PROF_BUSY 0x01
  90 #define PROF_ERROR 0x02
  91 #define PROF_OFF 0x03
  92 /* Masks for thread switches */
  93 #define PROF_OFF_THREAD 0x10
  94 #define PROF_ON_THREAD 0x0F
  95
  96 static unsigned short profiling = PROF_OFF;
  97 static size_t recursion_level;
  98 static unsigned short indices[INDEX_SIZE];
  99 static struct pfd_struct pfds[NUMPFDS];
 100 /* This holds a pointer to the last pfd effected for time tracking */
 101 static struct pfd_struct *last_pfd;
 102 /* These are used to track the time when we've lost the CPU so it doesn't count
 103  * against any of the profiled functions */
 104 static int profiling_thread = -1;
 105
 106 /* internal function prototypes */
 107 static void profile_timer_tick(void);
 108 static void profile_timer_unregister(void);
 109
 110 static void write_function_recursive(int fd, struct pfd_struct *pfd, int depth);
 111
 112 /* Be careful to use the right one for the size of your variable */
 113 #ifdef CPU_COLDFIRE
 114 #define ADDQI_L(_var,_value) \
 115     asm ("addq.l %[value],%[var];" \
 116          : [var] "+g" (_var) \
 117          : [value] "I" (_value) )
 118 #else
 119 #define ADDQI_L(var, value) var += value
 120 #endif
 121
 122 void profile_thread_stopped(int current_thread) {
 123     if (current_thread == profiling_thread) {
 124         /* If profiling is busy or idle */
 125         if (profiling < PROF_ERROR) {
 126             /* Unregister the timer so that other threads aren't interrupted */
 127             timer_unregister();
 128         }
 129         /* Make sure we don't waste time profiling when we're running the
 130          * wrong thread */
 131         profiling |= PROF_OFF_THREAD;
 132     }
 133 }
 134
 135 void profile_thread_started(int current_thread) {
 136     if (current_thread == profiling_thread) {
 137         /* Now we are allowed to profile again */
 138         profiling &= PROF_ON_THREAD;
 139         /* if profiling was busy or idle */
 140         if (profiling < PROF_ERROR) {
 141             /* After we de-mask, if profiling is active, reactivate the timer */
 142             timer_register(0, profile_timer_unregister,
 143                     TIMER_FREQ/10000, 0, profile_timer_tick IF_COP(, 0 ) );
 144         }
 145     }
 146 }
 147
 148 static void profile_timer_tick(void) {
 149     if (!profiling) {
 150         register struct pfd_struct *my_last_pfd = last_pfd;
 151         if (my_last_pfd) {
 152             ADDQI_L(my_last_pfd->time,1);
 153         }
 154     }
 155 }
 156
 157 static void profile_timer_unregister(void) {
 158     profiling = PROF_ERROR;
 159     profstop();
 160 }
 161
 162 /* This function clears the links on top level linkers, and clears the needed
 163  * parts of memory in the index array */
 164 void profstart(int current_thread) {
 165     recursion_level = 0;
 166     profiling_thread = current_thread;
 167     last_pfd = (struct pfd_struct*)0;
 168     pfds[0].link = 0;
 169     pfds[0].self_pc = 0;
 170     memset(indices,0,INDEX_SIZE * sizeof(unsigned short));
 171     timer_register(
 172         0, profile_timer_unregister, TIMER_FREQ/10000, 0, profile_timer_tick IF_COP(, 0 ) );
 173     profiling = PROF_ON;
 174 }
 175
 176 static void write_function_recursive(int fd, struct pfd_struct *pfd, int depth){
 177     unsigned short link = pfd->link;
 178     fdprintf(fd,"0x%08lX\t%08ld\t%08ld\t%04d\n", (size_t)pfd->self_pc,
 179             pfd->count, pfd->time, depth);
 180     if (link > 0 && link < NUMPFDS) {
 181         write_function_recursive(fd, &pfds[link], ++depth);
 182     }
 183 }
 184
 185 void profstop() {
 186     int profiling_exit = profiling;
 187     int fd = 0;
 188     int i;
 189     unsigned short current_index;
 190     timer_unregister();
 191     profiling = PROF_OFF;
 192     fd = open("/profile.out", O_WRONLY|O_CREAT|O_TRUNC);
 193     if (profiling_exit == PROF_ERROR) {
 194         fdprintf(fd,"Profiling exited with an error.\n");
 195         fdprintf(fd,"Overflow or timer stolen most likely.\n");
 196     }
 197     fdprintf(fd,"PROFILE_THREAD\tPFDS_USED\n");
 198     fdprintf(fd,"%08d\t%08d\n", profiling_thread,
 199         pfds[0].link);
 200     fdprintf(fd,"FUNCTION_PC\tCALL_COUNT\tTICKS\t\tDEPTH\n");
 201     for (i = 0; i < INDEX_SIZE; i++) {
 202         current_index = indices[i];
 203         if (current_index != 0) {
 204             write_function_recursive(fd, &pfds[current_index], 0);
 205         }
 206     }
 207     fdprintf(fd,"DEBUG PROFILE DATA FOLLOWS\n");
 208     fdprintf(fd,"INDEX\tLOCATION\tSELF_PC\t\tCOUNT\t\tTIME\t\tLINK\tCALLER_IDX\n");
 209     for (i = 0; i < NUMPFDS; i++) {
 210         struct pfd_struct *my_last_pfd = &pfds[i];
 211         if (my_last_pfd->self_pc != 0) {
 212             fdprintf(fd,
 213                     "%04d\t0x%08lX\t0x%08lX\t0x%08lX\t0x%08lX\t%04d\t0x%08lX\n",
 214                     i, (size_t)my_last_pfd, (size_t)my_last_pfd->self_pc,
 215                     my_last_pfd->count, my_last_pfd->time, my_last_pfd->link,
 216                     (size_t)my_last_pfd->caller );
 217         }
 218     }
 219     fdprintf(fd,"INDEX_ADDRESS=INDEX\n");
 220     for (i=0; i < INDEX_SIZE; i++) {
 221         fdprintf(fd,"%08lX=%04d\n",(size_t)&indices[i],indices[i]);
 222     }
 223     close(fd);
 224 }
 225
 226 void __cyg_profile_func_exit(void *self_pc, void *call_site) {
 227     (void)call_site;
 228     (void)self_pc;
 229     /* When we started timing, we set the time to the tick at that time
 230      * less the time already used in function */
 231     if (profiling) {
 232         return;
 233     }
 234     profiling = PROF_BUSY;
 235     {
 236         register unsigned short my_recursion_level = recursion_level;
 237         if (my_recursion_level) {
 238             my_recursion_level--;
 239             recursion_level = my_recursion_level;
 240         } else {
 241             /* This shouldn't be necessary, maybe exit could be called first */
 242             register struct pfd_struct *my_last_pfd = last_pfd;
 243             if (my_last_pfd) {
 244                 last_pfd = my_last_pfd->caller;
 245             }
 246         }
 247     }
 248     profiling = PROF_ON;
 249 }
 250
 251 #define ALLOCATE_PFD(temp) \
 252     temp = ++pfds[0].link;\
 253     if (temp >= NUMPFDS) goto overflow; \
 254     pfd = &pfds[temp];\
 255     pfd->self_pc = self_pc; pfd->count = 1; pfd->time = 0
 256
 257 void __cyg_profile_func_enter(void *self_pc, void *from_pc) {
 258     struct pfd_struct *pfd;
 259     struct pfd_struct *prev_pfd;
 260     unsigned short *pfd_index_pointer;
 261     unsigned short pfd_index;
 262
 263     /* check that we are profiling and that we aren't recursively invoked
 264      * this is equivalent to 'if (profiling != PROF_ON)' but it's faster */
 265     if (profiling) {
 266         return;
 267     }
 268     profiling = PROF_BUSY;
 269     /* A check that the PC is in the code range here wouldn't hurt, but this is
 270      * logically guaranteed to be a valid address unless the constants are
 271      * breaking the rules.  */
 272     pfd_index_pointer = &indices[((size_t)from_pc)&INDEX_MASK];
 273     pfd_index = *pfd_index_pointer;
 274     if (pfd_index == 0) {
 275         /* new caller, allocate new storage */
 276         ALLOCATE_PFD(pfd_index);
 277         pfd->link = 0;
 278         *pfd_index_pointer = pfd_index;
 279         goto done;
 280     }
 281     pfd = &pfds[pfd_index];
 282     if (pfd->self_pc == self_pc) {
 283         /* only / most recent function called by this caller, usual case */
 284         /* increment count, start timing and exit */
 285         goto found;
 286     }
 287     /* collision, bad for performance, look down the list of functions called by
 288      * colliding PCs */
 289     for (; /* goto done */; ) {
 290         pfd_index = pfd->link;
 291         if (pfd_index == 0) {
 292             /* no more previously called functions, allocate a new one */
 293             ALLOCATE_PFD(pfd_index);
 294             /* this function becomes the new head, link to the old head */
 295             pfd->link = *pfd_index_pointer;
 296             /* and set the index to point to this function */
 297             *pfd_index_pointer = pfd_index;
 298             /* start timing and exit */
 299             goto done;
 300         }
 301         /* move along the chain */
 302         prev_pfd = pfd;
 303         pfd = &pfds[pfd_index];
 304         if (pfd->self_pc == self_pc) {
 305             /* found ourself */
 306             /* Remove me from my old spot */
 307             prev_pfd->link = pfd->link;
 308             /* Link to the old head */
 309             pfd->link = *pfd_index_pointer;
 310             /* Make me head */
 311             *pfd_index_pointer = pfd_index;
 312             /* increment count, start timing and exit */
 313             goto found;
 314         }
 315
 316     }
 317 /* We've found a pfd, increment it */
 318 found:
 319     ADDQI_L(pfd->count,1);
 320 /* We've (found or created) and updated our pfd, save it and start timing */
 321 done:
 322     {
 323         register struct pfd_struct *my_last_pfd = last_pfd;
 324         if (pfd != my_last_pfd) {
 325             /* If we are not recursing */
 326             pfd->caller = my_last_pfd;
 327             last_pfd = pfd;
 328         } else {
 329             ADDQI_L(recursion_level,1);
 330         }
 331     }
 332     /* Start timing this function */
 333     profiling = PROF_ON;
 334     return;  /* normal return restores saved registers */
 335
 336 overflow:
 337     /* this is the same as 'profiling = PROF_ERROR' */
 338     profiling = PROF_ERROR;
 339     return;
 340 }
 341
 342
 343
 344