gen.subproj/stack_logging.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22
  23 /*      Bertrand from vmutils -> CF -> System */
  24
  25 #import "stack_logging.h"
  26
  27 #import <libc.h>
  28 #import <pthread.h>
  29 #import <mach/mach.h>
  30 #include <mach/vm_statistics.h>
  31
  32 extern void spin_lock(int *);
  33
  34 static inline void *allocate_pages(unsigned bytes) {
  35     void *address;
  36     if (vm_allocate(mach_task_self(), (vm_address_t *)&address, bytes,
  37                     VM_MAKE_TAG(VM_MEMORY_ANALYSIS_TOOL)| TRUE)) {
  38         address = 0;
  39     }
  40     return (void *)address;
  41 }
  42
  43 static inline void deallocate_pages(void *ptr, unsigned bytes) {
  44     vm_deallocate(mach_task_self(), (vm_address_t)ptr, bytes);
  45 }
  46
  47 static inline void copy_pages(const void *source, void *dest, unsigned bytes) {
  48     if (vm_copy(mach_task_self(), (vm_address_t)source, bytes, (vm_address_t)dest)) memmove(dest, source, bytes);
  49 }
  50
  51 /***************        Recording stack         ***********/
  52
  53 static void *first_frame_address(void) {
  54 #if 0
  55     return __builtin_frame_address(1);
  56 #elif defined(__ppc__)
  57     void *addr;
  58 #warning __builtin_frame_address IS BROKEN IN BEAKER: RADAR #2340421
  59     __asm__ volatile("mr %0, r1" : "=r" (addr));
  60     return addr;
  61 #else
  62 #warning first_frame_address WILL NOT BE FUNCTIONAL ON THIS ARCHITECTURE
  63     return NULL;
  64 #endif
  65 }
  66
  67 static void *next_frame_address(void *addr) {
  68     void *ret;
  69 #if defined(__MACH__) && defined(__i386__)
  70     __asm__ volatile("movl (%1),%0" : "=r" (ret) : "r" (addr));
  71 #elif defined(__MACH__) && defined(__ppc__)
  72     __asm__ volatile("lwz %0,0x0(%1)" : "=r" (ret) : "r" (addr));
  73 #elif defined(__hpux__)
  74     __asm__ volatile("ldw 0x0(%1),%0" : "=r" (ret) : "r" (addr));
  75 #elif defined(__svr4__)
  76     __asm__ volatile("ta 0x3");
  77     __asm__ volatile("ld [%1 + 56],%0" : "=r" (ret) : "r" (addr));
  78 #else
  79 #error Unknown architecture
  80 #endif
  81     return ret;
  82 }
  83
  84 #if defined(__i386__) || defined (__m68k__)
  85 #define FP_LINK_OFFSET 1
  86 #elif defined(__ppc__)
  87 #define FP_LINK_OFFSET 2
  88 #elif defined(__hppa__)
  89 #define FP_LINK_OFFSET -5
  90 #elif defined(__sparc__)
  91 #define FP_LINK_OFFSET 14
  92 #else
  93 #error  ********** Unimplemented architecture
  94 #endif
  95
  96 void thread_stack_pcs(vm_address_t *buffer, unsigned max, unsigned *nb) {
  97     void *addr;
  98     addr = first_frame_address();
  99     *nb = 0;
 100     while ((addr >= (void *)0x800) && (max--)) {
 101         vm_address_t    fp_link = (vm_address_t)(((unsigned *)addr)+FP_LINK_OFFSET);
 102         void    *addr2;
 103         buffer[*nb] = *((vm_address_t *)fp_link);
 104         (*nb)++;
 105         addr2 = next_frame_address(addr);
 106 #if defined(__ppc__)
 107         if ((unsigned)addr2 <= (unsigned)addr) break; // catch bozo frames
 108 #endif
 109         addr = addr2;
 110     }
 111 }
 112
 113 /***************        Uniquing stack          ***********/
 114
 115 #define MAX_COLLIDE     8
 116
 117 #define MAX_NUM_PC      512
 118
 119 static int enter_pair_in_table(unsigned *table, unsigned numPages, unsigned *uniquedParent, unsigned thisPC) {
 120     // uniquedParent is in-out; return 1 is collisions max not exceeded
 121     unsigned    base = numPages * vm_page_size / (sizeof(int)*2*2);
 122     unsigned    hash = base + (((*uniquedParent) << 4) ^ (thisPC >> 2)) % (base - 1); // modulo odd number for hashing
 123     unsigned    collisions = MAX_COLLIDE;
 124     while (collisions--) {
 125         unsigned        *head = table + hash*2;
 126         if (! head[0] && !head[1]) {
 127             /* end of chain; store this entry! */
 128             /* Note that we need to test for both head[0] and head[1] as (0, -1) is a valid entry */
 129             head[0] = thisPC;
 130             head[1] = *uniquedParent;
 131             *uniquedParent = hash;
 132             return 1;
 133         }
 134         if ((head[0] == thisPC) && (head[1] == *uniquedParent)) {
 135             /* we found the proper entry, the value for the pair is the entry offset */
 136             *uniquedParent = hash;
 137             return 1;
 138         }
 139         hash++;
 140         if (hash == base*2) hash = base;
 141     }
 142     return 0;
 143 }
 144
 145 unsigned stack_logging_get_unique_stack(unsigned **table, unsigned *table_num_pages, unsigned *stack_entries, unsigned count, unsigned num_hot_to_skip) {
 146     unsigned    uniquedParent = (unsigned)-1;
 147     // we skip the warmest entries that are an artefact of the code
 148     while (num_hot_to_skip--) {
 149         if (count > 0) { stack_entries++; count--; }
 150     }
 151     while (count--) {
 152         unsigned        thisPC = stack_entries[count];
 153         while (!enter_pair_in_table(*table, *table_num_pages, &uniquedParent, thisPC)) {
 154             unsigned    *newTable;
 155             unsigned    oldBytes = (*table_num_pages) * vm_page_size;
 156             newTable = allocate_pages(oldBytes*2);
 157             copy_pages(*table, newTable, oldBytes);
 158             deallocate_pages(*table, oldBytes);
 159             *table_num_pages *= 2;
 160             *table = newTable;
 161         }
 162     }
 163     return uniquedParent;
 164 }
 165
 166 /***************        Logging stack and arguments             ***********/
 167
 168 stack_logging_record_list_t *stack_logging_the_record_list = NULL;
 169
 170 int stack_logging_enable_logging = 0;
 171
 172 int stack_logging_dontcompact = 0;
 173
 174 static stack_logging_record_list_t *GrowLogRecords(stack_logging_record_list_t *records, unsigned desiredNumRecords) {
 175     stack_logging_record_list_t *new_records;
 176     unsigned    old_size = records->overall_num_bytes;
 177     if (desiredNumRecords*sizeof(stack_logging_record_t)+sizeof(stack_logging_record_list_t) < records->overall_num_bytes) return records;
 178     records->overall_num_bytes += records->overall_num_bytes + vm_page_size; // in order to always get an even number of pages
 179     new_records = allocate_pages(records->overall_num_bytes);
 180     copy_pages(records, new_records, old_size);
 181     deallocate_pages(records, old_size);
 182     return new_records;
 183 }
 184
 185 static void prepare_to_log_stack(void) {
 186     if (!stack_logging_the_record_list) {
 187         unsigned        totalSize = 4 * vm_page_size;
 188         stack_logging_the_record_list = allocate_pages(totalSize);
 189         memset(stack_logging_the_record_list, 0, sizeof(stack_logging_record_list_t));
 190         stack_logging_the_record_list->overall_num_bytes = totalSize;
 191         stack_logging_the_record_list->uniquing_table_num_pages = 128;
 192         stack_logging_the_record_list->uniquing_table = allocate_pages(stack_logging_the_record_list->uniquing_table_num_pages * vm_page_size);
 193     }
 194 }
 195
 196 void stack_logging_log_stack(unsigned type, unsigned arg1, unsigned arg2, unsigned arg3, unsigned result, unsigned num_hot_to_skip) {
 197     stack_logging_record_t      *rec;
 198     if (!stack_logging_enable_logging) return;
 199     // printf("stack_logging_log_stack 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
 200     if (type & stack_logging_flag_zone) {
 201         // just process it now and be done with it!
 202         arg1 = arg2; arg2 = arg3; arg3 = 0; type &= ~stack_logging_flag_zone;
 203     }
 204     if (type & stack_logging_flag_calloc) {
 205         // just process it now and be done with it!
 206         arg1 *= arg2; arg2 = arg3; arg3 = 0; type &= ~stack_logging_flag_calloc;
 207     }
 208     if (type & stack_logging_flag_object) {
 209         unsigned        *class = (unsigned *)arg1;
 210         arg1 = arg2 + class[5]; // corresponds to the instance_size field
 211         arg2 = 0; arg3 = 0; type = stack_logging_type_alloc;
 212     }
 213     if (type & stack_logging_flag_cleared) {
 214         type &= ~stack_logging_flag_cleared;
 215     }
 216     if (type & stack_logging_flag_handle) {
 217         if (stack_logging_type_alloc) {
 218             if (!result) return;
 219             stack_logging_log_stack(stack_logging_type_alloc, 0, 0, 0, result, num_hot_to_skip+1);
 220             stack_logging_log_stack(stack_logging_type_alloc, arg1, 0, 0, *((int *)result), num_hot_to_skip+1);
 221             return;
 222         }
 223         if (stack_logging_type_dealloc) {
 224             if (!arg1) return;
 225             stack_logging_log_stack(stack_logging_type_dealloc, *((int *)arg1), 0, 0, 0, num_hot_to_skip+1);
 226             stack_logging_log_stack(stack_logging_type_dealloc, arg1, 0, 0, 0, num_hot_to_skip+1);
 227             return;
 228         }
 229         printf("*** Unknown logging type: 0x%x\n", type);
 230     }
 231     if (type == stack_logging_flag_set_handle_size) {
 232         if (!arg1) return;
 233         // Thanks to a horrible hack, arg3 contains the prvious handle value
 234         if (arg3 == *((int *)arg1)) return;
 235         stack_logging_log_stack(stack_logging_type_dealloc, arg3, 0, 0, 0, num_hot_to_skip+1);
 236         stack_logging_log_stack(stack_logging_type_alloc, arg2, 0, 0, *((int *)arg1), num_hot_to_skip+1);
 237         return;
 238     }
 239     if (type == (stack_logging_type_dealloc|stack_logging_type_alloc)) {
 240         if (arg1 == result) return; // realloc had no effect, skipping
 241         if (!arg1) {
 242             // realloc(NULL, size) same as malloc(size)
 243             type = stack_logging_type_alloc; arg1 = arg2; arg2 = arg3; arg3 = 0;
 244         } else {
 245             // realloc(arg1, arg2) -> result is same as free(arg1); malloc(arg2) -> result
 246             stack_logging_log_stack(stack_logging_type_dealloc, arg1, 0, 0, 0, num_hot_to_skip+1);
 247             stack_logging_log_stack(stack_logging_type_alloc, arg2, 0, 0, result, num_hot_to_skip+1);
 248             return;
 249         }
 250     }
 251     if (type == stack_logging_type_dealloc) {
 252         // simple free
 253         if (!arg1) return; // free(nil)
 254     }
 255     prepare_to_log_stack();
 256     spin_lock(&stack_logging_the_record_list->lock);
 257     stack_logging_enable_logging = 0;
 258     stack_logging_the_record_list = GrowLogRecords(stack_logging_the_record_list, stack_logging_the_record_list->num_records + 1);
 259     rec = stack_logging_the_record_list->records + stack_logging_the_record_list->num_records;
 260     // We take care of the common case of alloc-dealloc
 261     if (!stack_logging_dontcompact && stack_logging_the_record_list->num_records && (type == stack_logging_type_dealloc) && arg1 && ((rec-1)->type == stack_logging_type_alloc) && (arg1 == STACK_LOGGING_DISGUISE((rec-1)->address))) {
 262         stack_logging_the_record_list->num_records--;
 263         // printf("Erased previous record in alloc-dealloc sequence\n");
 264     } else {
 265         unsigned        stack_entries[MAX_NUM_PC];
 266         unsigned        count = 0;
 267         rec->type = type;
 268         if (type == stack_logging_type_dealloc) {
 269             rec->argument = 0;
 270             rec->address = STACK_LOGGING_DISGUISE(arg1); // we disguise the address
 271         } else if (type == stack_logging_type_alloc) {
 272             rec->argument = arg1;
 273             rec->address = STACK_LOGGING_DISGUISE(result); // we disguise the address
 274         } else {
 275             rec->argument = arg2;
 276             rec->address = STACK_LOGGING_DISGUISE(arg1); // we disguise the address
 277         }
 278         // printf("Before getting samples  0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
 279         thread_stack_pcs(stack_entries, MAX_NUM_PC - 1, &count);
 280         // We put at the bottom of the stack a marker that denotes the thread (+1 for good measure...)
 281         stack_entries[count++] = (int)pthread_self() + 1;
 282         /* now let's unique the sample */
 283         // printf("Uniquing 0x%x 0x%x 0x%x 0x%x -> 0x%x\n", type, arg1, arg2, arg3, result);
 284         rec->uniqued_stack = stack_logging_get_unique_stack(&stack_logging_the_record_list->uniquing_table, &stack_logging_the_record_list->uniquing_table_num_pages, stack_entries, count, num_hot_to_skip+2); // we additionally skip the warmest 2 entries that are an artefact of the code
 285         stack_logging_the_record_list->num_records++;
 286     }
 287     stack_logging_enable_logging = 1;
 288     stack_logging_the_record_list->lock = 0;
 289 }
 290
 291 static kern_return_t default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr) {
 292     *ptr = (void *)address;
 293     return 0;
 294 }
 295
 296 static kern_return_t get_remote_records(task_t task, memory_reader_t reader, stack_logging_record_list_t **records) {
 297     // sets records
 298     vm_address_t        *remote_records_address_ref;
 299     kern_return_t       err;
 300     *records = NULL;
 301     err = reader(task, (vm_address_t)&stack_logging_the_record_list, sizeof(vm_address_t), (void **)&remote_records_address_ref);
 302     if (err) return err;
 303     if (!*remote_records_address_ref) {
 304         // printf("stack_logging: no stack record\n");
 305         return 0;
 306     }
 307     // printf("stack_logging: stack records at %p\n", (void *)(*remote_records_address_ref));
 308     // printf("stack_logging: reading %d bytes\n", sizeof(stack_logging_record_list_t));
 309     err = reader(task, *remote_records_address_ref, sizeof(stack_logging_record_list_t), (void **)records); // get the list head
 310     if (err) return err;
 311     // printf("stack_logging: overall num bytes = %d\n", records->overall_num_bytes);
 312     return reader(task, *remote_records_address_ref, (*records)->overall_num_bytes, (void **)records);
 313 }
 314
 315 kern_return_t stack_logging_get_frames(task_t task, memory_reader_t reader, vm_address_t address, vm_address_t *stack_frames_buffer, unsigned max_stack_frames, unsigned *num_frames) {
 316     stack_logging_record_list_t *records;
 317     kern_return_t       err;
 318     unsigned            index;
 319     unsigned            disguised = STACK_LOGGING_DISGUISE(address);
 320     if (!reader) reader = default_reader;
 321     *num_frames = 0;
 322     err = get_remote_records(task, reader, &records);
 323     if (err || !records) return err;
 324     // printf("stack_logging: %d records\n", records->num_records);
 325     index = 0;
 326     while (index < records->num_records) {
 327         stack_logging_record_t  *record = records->records + index;
 328         if (record->address == disguised) {
 329             return stack_logging_frames_for_uniqued_stack(task, reader, record->uniqued_stack, stack_frames_buffer, max_stack_frames, num_frames);
 330         }
 331         index++;
 332     }
 333     fprintf(stderr, "*** stack_logging: no record found for 0x%x\n", address);
 334     return 0;
 335 }
 336
 337 kern_return_t stack_logging_enumerate_records(task_t task, memory_reader_t reader, vm_address_t address, void enumerator(stack_logging_record_t, void *), void *context) {
 338     stack_logging_record_list_t *records;
 339     kern_return_t       err;
 340     unsigned            index;
 341     unsigned            disguised = STACK_LOGGING_DISGUISE(address);
 342     if (!reader) reader = default_reader;
 343     err = get_remote_records(task, reader, &records);
 344     if (err || !records) return err;
 345     // printf("stack_logging: %d records\n", records->num_records);
 346     index = 0;
 347     while (index < records->num_records) {
 348         stack_logging_record_t  *record = records->records + index;
 349         if (!address || (record->address == disguised)) enumerator(*record, context);
 350         index++;
 351     }
 352     return 0;
 353 }
 354
 355 kern_return_t stack_logging_frames_for_uniqued_stack(task_t task, memory_reader_t reader, unsigned uniqued_stack, vm_address_t *stack_frames_buffer, unsigned max_stack_frames, unsigned *num_frames) {
 356     stack_logging_record_list_t *records;
 357     unsigned            *uniquing_table;
 358     kern_return_t       err;
 359     if (!reader) reader = default_reader;
 360     *num_frames = 0;
 361     err = get_remote_records(task, reader, &records);
 362     if (err || !records) return err;
 363     err = reader(task, (vm_address_t)records->uniquing_table, records->uniquing_table_num_pages * vm_page_size, (void **)&uniquing_table);
 364     if (err) return err;
 365     while (max_stack_frames && (uniqued_stack != -1)) {
 366         unsigned        thisPC;
 367         if ((uniqued_stack * 2 + 1) * sizeof(unsigned) >= records->uniquing_table_num_pages * vm_page_size) {
 368             fprintf(stderr, "*** stack_logging: Invalid uniqued stack 0x%x", uniqued_stack);
 369             break;
 370         }
 371         thisPC = uniquing_table[uniqued_stack * 2];
 372         uniqued_stack = uniquing_table[uniqued_stack * 2 + 1];
 373         if (!thisPC && !uniqued_stack) {
 374             // Invalid entry
 375             fprintf(stderr, "*** stack_logging: Invalid entry 0x%x", thisPC);
 376             break;
 377         }
 378         stack_frames_buffer[0] = thisPC;
 379         stack_frames_buffer++;
 380         (*num_frames)++;
 381         max_stack_frames--;
 382     }
 383     return 0;
 384 }