u_debug_refcnt.c revision 1bb59b382a5702ebab37b0e7eb219e5b54769ffb 
1/**************************************************************************
2 *
3 * Copyright 2010 Luca Barbieri
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial
15 * portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 *
25 **************************************************************************/
26
27#if defined(DEBUG)
28
29/* see http://www.mozilla.org/performance/refcnt-balancer.html for what do with the output
30 * on Linux, use tools/addr2line.sh to postprocess it before anything else
31 **/
32
33#include <stdio.h>
34
35#include "util/u_debug.h"
36#include "util/u_debug_refcnt.h"
37#include "util/u_debug_stack.h"
38#include "util/u_debug_symbol.h"
39#include "util/u_string.h"
40#include "util/u_hash_table.h"
41#include "os/os_thread.h"
42
43int debug_refcnt_state;
44
45FILE* stream;
46
47/* TODO: maybe move this serial machinery to a stand-alone module and expose it? */
48pipe_static_mutex(serials_mutex);
49
50static struct util_hash_table* serials_hash;
51static unsigned serials_last;
52
53static unsigned hash_ptr(void* p)
54{
55   return (unsigned)(uintptr_t)p;
56}
57
58static int compare_ptr(void* a, void* b)
59{
60   if(a == b)
61      return 0;
62   else if(a < b)
63      return -1;
64   else
65      return 1;
66}
67
68static boolean debug_serial(void* p, unsigned* pserial)
69{
70   unsigned serial;
71   boolean found = TRUE;
72#ifdef PIPE_SUBSYSTEM_WINDOWS_USER
73   static boolean first = TRUE;
74
75   if (first) {
76      pipe_mutex_init(serials_mutex);
77      first = FALSE;
78   }
79#endif
80
81   pipe_mutex_lock(serials_mutex);
82   if(!serials_hash)
83      serials_hash = util_hash_table_create(hash_ptr, compare_ptr);
84   serial = (unsigned)(uintptr_t)util_hash_table_get(serials_hash, p);
85   if(!serial)
86   {
87      /* time to stop logging... (you'll have a 100 GB logfile at least at this point)
88       * TODO: avoid this
89       */
90      serial = ++serials_last;
91      if(!serial)
92      {
93         debug_error("More than 2^32 objects detected, aborting.\n");
94         os_abort();
95      }
96
97      util_hash_table_set(serials_hash, p, (void*)(uintptr_t)serial);
98      found = FALSE;
99   }
100   pipe_mutex_unlock(serials_mutex);
101   *pserial = serial;
102   return found;
103}
104
105static void debug_serial_delete(void* p)
106{
107   pipe_mutex_lock(serials_mutex);
108   util_hash_table_remove(serials_hash, p);
109   pipe_mutex_unlock(serials_mutex);
110}
111
112#define STACK_LEN 64
113
114static void dump_stack(const char* symbols[STACK_LEN])
115{
116   unsigned i;
117   for(i = 0; i < STACK_LEN; ++i)
118   {
119      if(symbols[i])
120         fprintf(stream, "%s\n", symbols[i]);
121   }
122   fprintf(stream, "\n");
123}
124
125void debug_reference_slowpath(const struct pipe_reference* p, debug_reference_descriptor get_desc, int change)
126{
127   if(debug_refcnt_state < 0)
128      return;
129
130   if(!debug_refcnt_state)
131   {
132      const char* filename = debug_get_option("GALLIUM_REFCNT_LOG", NULL);
133      if(filename && filename[0])
134         stream = fopen(filename, "wt");
135
136      if(stream)
137         debug_refcnt_state = 1;
138      else
139         debug_refcnt_state = -1;
140   }
141
142   if(debug_refcnt_state > 0)
143   {
144      struct debug_stack_frame frames[STACK_LEN];
145      const char* symbols[STACK_LEN];
146      char buf[1024];
147
148      unsigned i;
149      unsigned refcnt = p->count;
150      unsigned serial;
151      boolean existing = debug_serial((void*)p, &serial);
152
153      debug_backtrace_capture(frames, 1, STACK_LEN);
154      for(i = 0; i < STACK_LEN; ++i)
155      {
156         if(frames[i].function)
157            symbols[i] = debug_symbol_name_cached(frames[i].function);
158         else
159            symbols[i] = 0;
160      }
161
162      get_desc(buf, p);
163
164      if(!existing)
165      {
166         fprintf(stream, "<%s> %p %u Create\n", buf, (void *) p, serial);
167         dump_stack(symbols);
168
169         /* this is there to provide a gradual change even if we don't see the initialization */
170         for(i = 1; i <= refcnt - change; ++i)
171         {
172            fprintf(stream, "<%s> %p %u AddRef %u\n", buf, (void *) p,
173                    serial, i);
174            dump_stack(symbols);
175         }
176      }
177
178      if(change)
179      {
180         fprintf(stream, "<%s> %p %u %s %u\n", buf, (void *) p, serial,
181                 change > 0 ? "AddRef" : "Release", refcnt);
182         dump_stack(symbols);
183      }
184
185      if(!refcnt)
186      {
187         debug_serial_delete((void*)p);
188         fprintf(stream, "<%s> %p %u Destroy\n", buf, (void *) p, serial);
189         dump_stack(symbols);
190      }
191
192      fflush(stream);
193   }
194}
195#endif
196