RTS tidyup sweep, first phase
[ghc.git] / rts / LdvProfile.c
1 /* -----------------------------------------------------------------------------
2 *
3 * (c) The GHC Team, 2001
4 * Author: Sungwoo Park
5 *
6 * Lag/Drag/Void profiling.
7 *
8 * ---------------------------------------------------------------------------*/
9
10 #ifdef PROFILING
11
12 #include "PosixSource.h"
13 #include "Rts.h"
14
15 #include "Profiling.h"
16 #include "Stats.h"
17 #include "RtsUtils.h"
18 #include "Schedule.h"
19
20 /* --------------------------------------------------------------------------
21 * Fills in the slop when a *dynamic* closure changes its type.
22 * First calls LDV_recordDead() to declare the closure is dead, and then
23 * fills in the slop.
24 *
25 * Invoked when:
26 * 1) blackholing, UPD_BH_UPDATABLE() and UPD_BH_SINGLE_ENTRY (in
27 * includes/StgMacros.h), threadLazyBlackHole() and
28 * threadSqueezeStack() (in GC.c).
29 * 2) updating with indirection closures, updateWithIndirection()
30 * and updateWithPermIndirection() (in Storage.h).
31 *
32 * LDV_recordDead_FILL_SLOP_DYNAMIC() is not called on 'inherently used'
33 * closures such as TSO. It is not called on PAP because PAP is not updatable.
34 * ----------------------------------------------------------------------- */
35 void
36 LDV_recordDead_FILL_SLOP_DYNAMIC( StgClosure *p )
37 {
38 nat size, i;
39
40 #if defined(__GNUC__) && __GNUC__ < 3 && defined(DEBUG)
41 #error Please use gcc 3.0+ to compile this file with DEBUG; gcc < 3.0 miscompiles it
42 #endif
43
44 if (era > 0) {
45 // very like FILL_SLOP(), except that we call LDV_recordDead().
46 size = closure_sizeW(p);
47
48 LDV_recordDead((StgClosure *)(p), size);
49
50 if (size > sizeofW(StgThunkHeader)) {
51 for (i = 0; i < size - sizeofW(StgThunkHeader); i++) {
52 ((StgThunk *)(p))->payload[i] = 0;
53 }
54 }
55 }
56 }
57
58 /* --------------------------------------------------------------------------
59 * This function is called eventually on every object destroyed during
60 * a garbage collection, whether it is a major garbage collection or
61 * not. If c is an 'inherently used' closure, nothing happens. If c
62 * is an ordinary closure, LDV_recordDead() is called on c with its
63 * proper size which excludes the profiling header portion in the
64 * closure. Returns the size of the closure, including the profiling
65 * header portion, so that the caller can find the next closure.
66 * ----------------------------------------------------------------------- */
67 STATIC_INLINE nat
68 processHeapClosureForDead( StgClosure *c )
69 {
70 nat size;
71 const StgInfoTable *info;
72
73 info = get_itbl(c);
74
75 info = c->header.info;
76 if (IS_FORWARDING_PTR(info)) {
77 // The size of the evacuated closure is currently stored in
78 // the LDV field. See SET_EVACUAEE_FOR_LDV() in
79 // includes/StgLdvProf.h.
80 return LDVW(c);
81 }
82 info = INFO_PTR_TO_STRUCT(info);
83
84 ASSERT(((LDVW(c) & LDV_CREATE_MASK) >> LDV_SHIFT) <= era &&
85 ((LDVW(c) & LDV_CREATE_MASK) >> LDV_SHIFT) > 0);
86 ASSERT(((LDVW(c) & LDV_STATE_MASK) == LDV_STATE_CREATE) ||
87 (
88 (LDVW(c) & LDV_LAST_MASK) <= era &&
89 (LDVW(c) & LDV_LAST_MASK) > 0
90 ));
91
92
93 size = closure_sizeW(c);
94
95 switch (info->type) {
96 /*
97 'inherently used' cases: do nothing.
98 */
99 case TSO:
100 case MVAR_CLEAN:
101 case MVAR_DIRTY:
102 case MUT_ARR_PTRS_CLEAN:
103 case MUT_ARR_PTRS_DIRTY:
104 case MUT_ARR_PTRS_FROZEN:
105 case MUT_ARR_PTRS_FROZEN0:
106 case ARR_WORDS:
107 case WEAK:
108 case MUT_VAR_CLEAN:
109 case MUT_VAR_DIRTY:
110 case BCO:
111 case STABLE_NAME:
112 case TVAR_WATCH_QUEUE:
113 case TVAR:
114 case TREC_HEADER:
115 case TREC_CHUNK:
116 case INVARIANT_CHECK_QUEUE:
117 case ATOMIC_INVARIANT:
118 return size;
119
120 /*
121 ordinary cases: call LDV_recordDead().
122 */
123 case THUNK:
124 case THUNK_1_0:
125 case THUNK_0_1:
126 case THUNK_SELECTOR:
127 case THUNK_2_0:
128 case THUNK_1_1:
129 case THUNK_0_2:
130 case AP:
131 case PAP:
132 case AP_STACK:
133 case CONSTR:
134 case CONSTR_1_0:
135 case CONSTR_0_1:
136 case CONSTR_2_0:
137 case CONSTR_1_1:
138 case CONSTR_0_2:
139 case FUN:
140 case FUN_1_0:
141 case FUN_0_1:
142 case FUN_2_0:
143 case FUN_1_1:
144 case FUN_0_2:
145 case BLACKHOLE:
146 case CAF_BLACKHOLE:
147 case IND_PERM:
148 case IND_OLDGEN_PERM:
149 /*
150 'Ingore' cases
151 */
152 // Why can we ignore IND/IND_OLDGEN closures? We assume that
153 // any census is preceded by a major garbage collection, which
154 // IND/IND_OLDGEN closures cannot survive. Therefore, it is no
155 // use considering IND/IND_OLDGEN closures in the meanwhile
156 // because they will perish before the next census at any
157 // rate.
158 case IND:
159 case IND_OLDGEN:
160 // Found a dead closure: record its size
161 LDV_recordDead(c, size);
162 return size;
163
164 /*
165 Error case
166 */
167 // static objects
168 case IND_STATIC:
169 case CONSTR_STATIC:
170 case FUN_STATIC:
171 case THUNK_STATIC:
172 case CONSTR_NOCAF_STATIC:
173 // stack objects
174 case UPDATE_FRAME:
175 case CATCH_FRAME:
176 case STOP_FRAME:
177 case RET_DYN:
178 case RET_BCO:
179 case RET_SMALL:
180 case RET_BIG:
181 // others
182 case BLOCKED_FETCH:
183 case FETCH_ME:
184 case FETCH_ME_BQ:
185 case RBH:
186 case REMOTE_REF:
187 case INVALID_OBJECT:
188 default:
189 barf("Invalid object in processHeapClosureForDead(): %d", info->type);
190 return 0;
191 }
192 }
193
194 /* --------------------------------------------------------------------------
195 * Calls processHeapClosureForDead() on every *dead* closures in the
196 * heap blocks starting at bd.
197 * ----------------------------------------------------------------------- */
198 static void
199 processHeapForDead( bdescr *bd )
200 {
201 StgPtr p;
202
203 while (bd != NULL) {
204 p = bd->start;
205 while (p < bd->free) {
206 p += processHeapClosureForDead((StgClosure *)p);
207 while (p < bd->free && !*p) // skip slop
208 p++;
209 }
210 ASSERT(p == bd->free);
211 bd = bd->link;
212 }
213 }
214
215 /* --------------------------------------------------------------------------
216 * Calls processHeapClosureForDead() on every *dead* closures in the nursery.
217 * ----------------------------------------------------------------------- */
218 static void
219 processNurseryForDead( void )
220 {
221 StgPtr p, bdLimit;
222 bdescr *bd;
223
224 bd = MainCapability.r.rNursery->blocks;
225 while (bd->start < bd->free) {
226 p = bd->start;
227 bdLimit = bd->start + BLOCK_SIZE_W;
228 while (p < bd->free && p < bdLimit) {
229 p += processHeapClosureForDead((StgClosure *)p);
230 while (p < bd->free && p < bdLimit && !*p) // skip slop
231 p++;
232 }
233 bd = bd->link;
234 if (bd == NULL)
235 break;
236 }
237 }
238
239 /* --------------------------------------------------------------------------
240 * Calls processHeapClosureForDead() on every *dead* closures in the
241 * small object pool.
242 * ----------------------------------------------------------------------- */
243 static void
244 processSmallObjectPoolForDead( void )
245 {
246 bdescr *bd;
247 StgPtr p;
248
249 for (bd = g0s0->blocks; bd != NULL; bd = bd->link) {
250 p = bd->start;
251 while (p < bd->free) {
252 p += processHeapClosureForDead((StgClosure *)p);
253 while (p < bd->free && !*p) // skip slop
254 p++;
255 }
256 ASSERT(p == bd->free);
257 }
258 }
259
260 /* --------------------------------------------------------------------------
261 * Calls processHeapClosureForDead() on every *dead* closures in the closure
262 * chain.
263 * ----------------------------------------------------------------------- */
264 static void
265 processChainForDead( bdescr *bd )
266 {
267 // Any object still in the chain is dead!
268 while (bd != NULL) {
269 if (!(bd->flags & BF_PINNED)) {
270 processHeapClosureForDead((StgClosure *)bd->start);
271 }
272 bd = bd->link;
273 }
274 }
275
276 /* --------------------------------------------------------------------------
277 * Start a census for *dead* closures, and calls
278 * processHeapClosureForDead() on every closure which died in the
279 * current garbage collection. This function is called from a garbage
280 * collector right before tidying up, when all dead closures are still
281 * stored in the heap and easy to identify. Generations 0 through N
282 * have just beed garbage collected.
283 * ----------------------------------------------------------------------- */
284 void
285 LdvCensusForDead( nat N )
286 {
287 nat g, s;
288
289 // ldvTime == 0 means that LDV profiling is currently turned off.
290 if (era == 0)
291 return;
292
293 if (RtsFlags.GcFlags.generations == 1) {
294 //
295 // Todo: support LDV for two-space garbage collection.
296 //
297 barf("Lag/Drag/Void profiling not supported with -G1");
298 } else {
299 for (g = 0; g <= N; g++)
300 for (s = 0; s < generations[g].n_steps; s++) {
301 if (g == 0 && s == 0) {
302 processSmallObjectPoolForDead();
303 processNurseryForDead();
304 processChainForDead(generations[g].steps[s].large_objects);
305 } else{
306 processHeapForDead(generations[g].steps[s].old_blocks);
307 processChainForDead(generations[g].steps[s].large_objects);
308 }
309 }
310 }
311 }
312
313 /* --------------------------------------------------------------------------
314 * Regard any closure in the current heap as dead or moribund and update
315 * LDV statistics accordingly.
316 * Called from shutdownHaskell() in RtsStartup.c.
317 * Also, stops LDV profiling by resetting ldvTime to 0.
318 * ----------------------------------------------------------------------- */
319 void
320 LdvCensusKillAll( void )
321 {
322 LdvCensusForDead(RtsFlags.GcFlags.generations - 1);
323 }
324
325 #endif /* PROFILING */