drd/drd_malloc_wrappers.c

   1 /*
   2   This file is part of drd, a thread error detector.
   3
   4   Copyright (C) 2006-2017 Bart Van Assche <bvanassche@acm.org>.
   5
   6   This program is free software; you can redistribute it and/or
   7   modify it under the terms of the GNU General Public License as
   8   published by the Free Software Foundation; either version 2 of the
   9   License, or (at your option) any later version.
  10
  11   This program is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with this program; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19   02111-1307, USA.
  20
  21   The GNU General Public License is contained in the file COPYING.
  22 */
  23
  24
  25 #include "drd_malloc_wrappers.h"
  26 #include "drd_thread.h"
  27 #include "pub_tool_basics.h"
  28 #include "pub_tool_execontext.h"
  29 #include "pub_tool_hashtable.h"
  30 #include "pub_tool_libcassert.h"
  31 #include "pub_tool_libcbase.h"
  32 #include "pub_tool_libcprint.h"
  33 #include "pub_tool_mallocfree.h"
  34 #include "pub_tool_options.h"
  35 #include "pub_tool_replacemalloc.h"
  36 #include "pub_tool_threadstate.h"
  37 #include "pub_tool_tooliface.h"
  38
  39
  40 /* Local type definitions. */
  41
  42 /**
  43  * Node with per-allocation information that will be stored in a hash map.
  44  * As specified in <pub_tool_hashtable.h>, the first member must be a pointer
  45  * and the second member must be an UWord.
  46  */
  47 typedef struct _DRD_Chunk {
  48    struct _DRD_Chunk* next;
  49    UWord              data;   // pointer to actual block
  50    SizeT              size;   // size requested
  51    ExeContext*        where;  // where it was allocated
  52 } DRD_Chunk;
  53
  54
  55 /* Local variables. */
  56
  57 static StartUsingMem s_start_using_mem_callback;
  58 static StopUsingMem  s_stop_using_mem_callback;
  59 /* Statistics. */
  60 static SizeT s_cmalloc_n_mallocs  = 0;
  61 static SizeT s_cmalloc_n_frees    = 0;
  62 static SizeT s_cmalloc_bs_mallocd = 0;
  63 /* Record malloc'd blocks. */
  64 static VgHashTable *s_malloc_list = NULL;
  65
  66
  67 /* Function definitions. */
  68
  69 /** Allocate client memory memory and update the hash map. */
  70 static void* new_block(ThreadId tid, SizeT size, SizeT align, Bool is_zeroed)
  71 {
  72    void* p;
  73
  74    p = VG_(cli_malloc)(align, size);
  75    if (!p)
  76       return NULL;
  77    if (is_zeroed)
  78       VG_(memset)(p, 0, size);
  79
  80    DRD_(malloclike_block)(tid, (Addr)p, size);
  81
  82    return p;
  83 }
  84
  85 /**
  86  * Store information about a memory block that has been allocated by
  87  * malloc() or a malloc() replacement in the hash map.
  88  */
  89 void DRD_(malloclike_block)(const ThreadId tid, const Addr p, const SizeT size)
  90 {
  91    DRD_Chunk* mc;
  92
  93    tl_assert(p);
  94
  95    if (size > 0)
  96       s_start_using_mem_callback(p, size, 0/*ec_uniq*/);
  97
  98    s_cmalloc_n_mallocs++;
  99    // Only update this stat if allocation succeeded.
 100    s_cmalloc_bs_mallocd += size;
 101
 102    mc = VG_(malloc)("drd.malloc_wrappers.cDC.1", sizeof(DRD_Chunk));
 103    mc->data  = p;
 104    mc->size  = size;
 105    mc->where = VG_(record_ExeContext)(tid, 0);
 106    VG_(HT_add_node)(s_malloc_list, mc);
 107 }
 108
 109 static void handle_free(ThreadId tid, void* p)
 110 {
 111    Bool success;
 112
 113    tl_assert(p);
 114    success = DRD_(freelike_block)(tid, (Addr)p, True);
 115    tl_assert(success);
 116 }
 117
 118 /**
 119  * Remove the information that was stored by DRD_(malloclike_block)() about
 120  * a memory block.
 121  */
 122 Bool DRD_(freelike_block)(const ThreadId tid, const Addr p, const Bool dealloc)
 123 {
 124    DRD_Chunk* mc;
 125
 126    tl_assert(p);
 127
 128    s_cmalloc_n_frees++;
 129
 130    mc = VG_(HT_lookup)(s_malloc_list, (UWord)p);
 131    if (mc)
 132    {
 133       tl_assert(p == mc->data);
 134       if (mc->size > 0)
 135          s_stop_using_mem_callback(mc->data, mc->size);
 136       if (dealloc)
 137          VG_(cli_free)((void*)p);
 138       VG_(HT_remove)(s_malloc_list, (UWord)p);
 139       VG_(free)(mc);
 140       return True;
 141    }
 142    return False;
 143 }
 144
 145 /** Wrapper for malloc(). */
 146 static void* drd_malloc(ThreadId tid, SizeT n)
 147 {
 148    return new_block(tid, n, VG_(clo_alignment), /*is_zeroed*/False);
 149 }
 150
 151 /** Wrapper for memalign(). */
 152 static void* drd_memalign(ThreadId tid, SizeT align, SizeT n)
 153 {
 154    return new_block(tid, n, align, /*is_zeroed*/False);
 155 }
 156
 157 /** Wrapper for calloc(). */
 158 static void* drd_calloc(ThreadId tid, SizeT nmemb, SizeT size1)
 159 {
 160    return new_block(tid, nmemb*size1, VG_(clo_alignment),
 161                           /*is_zeroed*/True);
 162 }
 163
 164 /** Wrapper for free(). */
 165 static void drd_free(ThreadId tid, void* p)
 166 {
 167    handle_free(tid, p);
 168 }
 169
 170 /**
 171  * Wrapper for realloc(). Returns a pointer to the new block of memory, or
 172  * NULL if no new block could not be allocated. Notes:
 173  * - realloc(NULL, size) has the same effect as malloc(size).
 174  * - realloc(p, 0) has the same effect as free(p).
 175  * - success is not guaranteed even if the requested size is smaller than the
 176  *   allocated size.
 177 */
 178 static void* drd_realloc(ThreadId tid, void* p_old, SizeT new_size)
 179 {
 180    DRD_Chunk* mc;
 181    void*      p_new;
 182    SizeT      old_size;
 183
 184    if (! p_old)
 185       return drd_malloc(tid, new_size);
 186
 187    if (new_size == 0)
 188    {
 189       drd_free(tid, p_old);
 190       return NULL;
 191    }
 192
 193    s_cmalloc_n_mallocs++;
 194    s_cmalloc_n_frees++;
 195    s_cmalloc_bs_mallocd += new_size;
 196
 197    mc = VG_(HT_lookup)(s_malloc_list, (UWord)p_old);
 198    if (mc == NULL)
 199    {
 200       tl_assert(0);
 201       return NULL;
 202    }
 203
 204    old_size = mc->size;
 205
 206    if (old_size == new_size)
 207    {
 208       /* size unchanged */
 209       mc->where = VG_(record_ExeContext)(tid, 0);
 210       p_new = p_old;
 211    }
 212    else if (new_size < old_size)
 213    {
 214       /* new size is smaller but nonzero */
 215       s_stop_using_mem_callback(mc->data + new_size, old_size - new_size);
 216       mc->size = new_size;
 217       mc->where = VG_(record_ExeContext)(tid, 0);
 218       p_new = p_old;
 219    }
 220    else
 221    {
 222       /* new size is bigger */
 223       p_new = VG_(cli_malloc)(VG_(clo_alignment), new_size);
 224
 225       if (p_new)
 226       {
 227          /* Copy from old to new. */
 228          VG_(memcpy)(p_new, p_old, mc->size);
 229
 230          /* Free old memory. */
 231          if (mc->size > 0)
 232             s_stop_using_mem_callback(mc->data, mc->size);
 233          VG_(cli_free)(p_old);
 234          VG_(HT_remove)(s_malloc_list, (UWord)p_old);
 235
 236          /* Update state information. */
 237          mc->data  = (Addr)p_new;
 238          mc->size  = new_size;
 239          mc->where = VG_(record_ExeContext)(tid, 0);
 240          VG_(HT_add_node)(s_malloc_list, mc);
 241          s_start_using_mem_callback((Addr)p_new, new_size, 0/*ec_uniq*/);
 242       }
 243       else
 244       {
 245          /* Allocation failed -- leave original block untouched. */
 246       }
 247    }
 248
 249    return p_new;
 250 }
 251
 252 /** Wrapper for __builtin_new(). */
 253 static void* drd___builtin_new(ThreadId tid, SizeT n)
 254 {
 255    return new_block(tid, n, VG_(clo_alignment), /*is_zeroed*/False);
 256 }
 257
 258 /** Wrapper for __builtin_delete(). */
 259 static void drd___builtin_delete(ThreadId tid, void* p)
 260 {
 261    handle_free(tid, p);
 262 }
 263
 264 /** Wrapper for __builtin_vec_new(). */
 265 static void* drd___builtin_vec_new(ThreadId tid, SizeT n)
 266 {
 267    return new_block(tid, n, VG_(clo_alignment), /*is_zeroed*/False);
 268 }
 269
 270 /** Wrapper for __builtin_vec_delete(). */
 271 static void drd___builtin_vec_delete(ThreadId tid, void* p)
 272 {
 273    handle_free(tid, p);
 274 }
 275
 276 /**
 277  * Wrapper for malloc_usable_size() / malloc_size(). This function takes
 278  * a pointer to a block allocated by `malloc' and returns the amount of space
 279  * that is available in the block. This may or may not be more than the size
 280  * requested from `malloc', due to alignment or minimum size constraints.
 281  */
 282 static SizeT drd_malloc_usable_size(ThreadId tid, void* p)
 283 {
 284    DRD_Chunk* mc;
 285
 286    mc = VG_(HT_lookup)(s_malloc_list, (UWord)p);
 287
 288    return mc ? mc->size : 0;
 289 }
 290
 291 void DRD_(register_malloc_wrappers)(const StartUsingMem start_callback,
 292                                     const StopUsingMem stop_callback)
 293 {
 294    tl_assert(s_malloc_list == 0);
 295    s_malloc_list = VG_(HT_construct)("drd_malloc_list");
 296    tl_assert(start_callback);
 297    tl_assert(stop_callback);
 298
 299    s_start_using_mem_callback = start_callback;
 300    s_stop_using_mem_callback  = stop_callback;
 301
 302    VG_(needs_malloc_replacement)(drd_malloc,
 303                                  drd___builtin_new,
 304                                  drd___builtin_vec_new,
 305                                  drd_memalign,
 306                                  drd_calloc,
 307                                  drd_free,
 308                                  drd___builtin_delete,
 309                                  drd___builtin_vec_delete,
 310                                  drd_realloc,
 311                                  drd_malloc_usable_size,
 312                                  0);
 313 }
 314
 315 Bool DRD_(heap_addrinfo)(Addr const a,
 316                          Addr* const data,
 317                          SizeT* const size,
 318                          ExeContext** const where)
 319 {
 320    DRD_Chunk* mc;
 321
 322    tl_assert(data);
 323    tl_assert(size);
 324    tl_assert(where);
 325
 326    VG_(HT_ResetIter)(s_malloc_list);
 327    while ((mc = VG_(HT_Next)(s_malloc_list)))
 328    {
 329       if (mc->data <= a && a < mc->data + mc->size)
 330       {
 331          *data  = mc->data;
 332          *size  = mc->size;
 333          *where = mc->where;
 334          return True;
 335       }
 336    }
 337    return False;
 338 }
 339
 340 /*------------------------------------------------------------*/
 341 /*--- Statistics printing                                  ---*/
 342 /*------------------------------------------------------------*/
 343
 344 void DRD_(print_malloc_stats)(void)
 345 {
 346    DRD_Chunk* mc;
 347    SizeT     nblocks = 0;
 348    SizeT     nbytes  = 0;
 349
 350    if (VG_(clo_verbosity) == 0)
 351       return;
 352    if (VG_(clo_xml))
 353       return;
 354
 355    /* Count memory still in use. */
 356    VG_(HT_ResetIter)(s_malloc_list);
 357    while ((mc = VG_(HT_Next)(s_malloc_list)))
 358    {
 359       nblocks++;
 360       nbytes += mc->size;
 361    }
 362
 363    VG_(message)(Vg_DebugMsg,
 364                 "malloc/free: in use at exit: %lu bytes in %lu blocks.\n",
 365                 nbytes, nblocks);
 366    VG_(message)(Vg_DebugMsg,
 367                 "malloc/free: %lu allocs, %lu frees, %lu bytes allocated.\n",
 368                 s_cmalloc_n_mallocs,
 369                 s_cmalloc_n_frees, s_cmalloc_bs_mallocd);
 370    if (VG_(clo_verbosity) > 1)
 371       VG_(message)(Vg_DebugMsg, " \n");
 372 }
 373
 374 /*--------------------------------------------------------------------*/
 375 /*--- end                                                          ---*/
 376 /*--------------------------------------------------------------------*/