1 /* -----------------------------------------------------------------------------
2 * $Id: Updates.h,v 1.29 2003/01/25 15:54:48 wolfgang Exp $
4 * (c) The GHC Team, 1998-1999
6 * Definitions related to updates.
8 * ---------------------------------------------------------------------------*/
13 /* -----------------------------------------------------------------------------
14 Update a closure with an indirection. This may also involve waking
15 up a queue of blocked threads waiting on the result of this
17 -------------------------------------------------------------------------- */
19 /* ToDo: overwrite slop words with something safe in case sanity checking
21 * (I think the fancy version of the GC is supposed to do this too.)
24 /* This expands to a fair chunk of code, what with waking up threads
25 * and checking whether we're updating something in a old generation.
26 * preferably don't use this macro inline in compiled code.
30 # define UPD_IND(updclosure, heapptr) UPD_PERM_IND(updclosure,heapptr)
32 # define UPD_IND(updclosure, heapptr) UPD_REAL_IND(updclosure,heapptr)
35 /* UPD_IND actually does a PERM_IND if TICKY_TICKY is on;
36 if you *really* need an IND use UPD_REAL_IND
39 #define UPD_REAL_IND(updclosure, heapptr) \
41 const StgInfoTable *info; \
42 if (Bdescr((P_)updclosure)->u.back != (bdescr *)BaseReg) { \
43 info = LOCK_CLOSURE(updclosure); \
45 info = updclosure->header.info; \
47 AWAKEN_BQ(info,updclosure); \
48 updateWithIndirection(info, \
49 (StgClosure *)updclosure, \
50 (StgClosure *)heapptr); \
53 #define UPD_REAL_IND(updclosure, heapptr) \
55 const StgInfoTable *info; \
56 info = ((StgClosure *)updclosure)->header.info; \
57 AWAKEN_BQ(info,updclosure); \
58 updateWithIndirection(info, \
59 (StgClosure *)updclosure, \
60 (StgClosure *)heapptr); \
64 #define UPD_STATIC_IND(updclosure, heapptr) \
66 const StgInfoTable *info; \
67 info = ((StgClosure *)updclosure)->header.info; \
68 AWAKEN_STATIC_BQ(info,updclosure); \
69 updateWithStaticIndirection(info, \
70 (StgClosure *)updclosure, \
71 (StgClosure *)heapptr); \
74 #if defined(PROFILING) || defined(TICKY_TICKY)
75 #define UPD_PERM_IND(updclosure, heapptr) \
77 const StgInfoTable *info; \
78 info = ((StgClosure *)updclosure)->header.info; \
79 AWAKEN_BQ(info,updclosure); \
80 updateWithPermIndirection(info, \
81 (StgClosure *)updclosure, \
82 (StgClosure *)heapptr); \
87 #define UPD_IND_NOLOCK(updclosure, heapptr) \
89 const StgInfoTable *info; \
90 info = updclosure->header.info; \
91 AWAKEN_BQ(info,updclosure); \
92 updateWithIndirection(info, \
93 (StgClosure *)updclosure, \
94 (StgClosure *)heapptr); \
96 #elif defined(RTS_SUPPORTS_THREADS)
99 # define UPD_IND_NOLOCK(updclosure, heapptr) \
101 const StgInfoTable *info; \
102 info = ((StgClosure *)updclosure)->header.info; \
103 AWAKEN_BQ_NOLOCK(info,updclosure); \
104 updateWithPermIndirection(info, \
105 (StgClosure *)updclosure, \
106 (StgClosure *)heapptr); \
109 # define UPD_IND_NOLOCK(updclosure, heapptr) \
111 const StgInfoTable *info; \
112 info = ((StgClosure *)updclosure)->header.info; \
113 AWAKEN_BQ_NOLOCK(info,updclosure); \
114 updateWithIndirection(info, \
115 (StgClosure *)updclosure, \
116 (StgClosure *)heapptr); \
121 #define UPD_IND_NOLOCK(updclosure,heapptr) UPD_IND(updclosure,heapptr)
124 /* -----------------------------------------------------------------------------
125 Awaken any threads waiting on this computation
126 -------------------------------------------------------------------------- */
131 In a parallel setup several types of closures might have a blocking queue:
132 BLACKHOLE_BQ ... same as in the default concurrent setup; it will be
133 reawakened via calling UPD_IND on that closure after
134 having finished the computation of the graph
135 FETCH_ME_BQ ... a global indirection (FETCH_ME) may be entered by a
136 local TSO, turning it into a FETCH_ME_BQ; it will be
137 reawakened via calling processResume
138 RBH ... a revertible black hole may be entered by another
139 local TSO, putting it onto its blocking queue; since
140 RBHs only exist while the corresponding closure is in
141 transit, they will be reawakened via calling
142 convertToFetchMe (upon processing an ACK message)
144 In a parallel setup a blocking queue may contain 3 types of closures:
145 TSO ... as in the default concurrent setup
146 BLOCKED_FETCH ... indicating that a TSO on another PE is waiting for
147 the result of the current computation
148 CONSTR ... an RBHSave closure (which contains data ripped out of
149 the closure to make room for a blocking queue; since
150 it only contains data we use the exisiting type of
151 a CONSTR closure); this closure is the end of a
152 blocking queue for an RBH closure; it only exists in
153 this kind of blocking queue and must be at the end
156 extern void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
157 #define DO_AWAKEN_BQ(bqe, node) STGCALL2(awakenBlockedQueue, bqe, node);
159 #define AWAKEN_BQ(info,closure) \
160 if (info == &stg_BLACKHOLE_BQ_info || \
161 info == &stg_FETCH_ME_BQ_info || \
162 get_itbl(closure)->type == RBH) { \
163 DO_AWAKEN_BQ(((StgBlockingQueue *)closure)->blocking_queue, closure); \
168 extern void awakenBlockedQueue(StgBlockingQueueElement *q, StgClosure *node);
169 #define DO_AWAKEN_BQ(bq, node) STGCALL2(awakenBlockedQueue, bq, node);
171 /* In GranSim we don't have FETCH_ME or FETCH_ME_BQ closures, so they are
172 not checked. The rest of the code is the same as for GUM.
174 #define AWAKEN_BQ(info,closure) \
175 if (info == &stg_BLACKHOLE_BQ_info || \
176 get_itbl(closure)->type == RBH) { \
177 DO_AWAKEN_BQ(((StgBlockingQueue *)closure)->blocking_queue, closure); \
181 #else /* !GRAN && !PAR */
183 extern void awakenBlockedQueue(StgTSO *q);
184 #define DO_AWAKEN_BQ(closure) \
185 STGCALL1(awakenBlockedQueue, \
186 ((StgBlockingQueue *)closure)->blocking_queue);
188 #define AWAKEN_BQ(info,closure) \
189 if (info == &stg_BLACKHOLE_BQ_info) { \
190 DO_AWAKEN_BQ(closure); \
193 #define AWAKEN_STATIC_BQ(info,closure) \
194 if (info == &stg_BLACKHOLE_BQ_STATIC_info) { \
195 DO_AWAKEN_BQ(closure); \
198 #ifdef RTS_SUPPORTS_THREADS
199 extern void awakenBlockedQueueNoLock(StgTSO *q);
200 #define DO_AWAKEN_BQ_NOLOCK(closure) \
201 STGCALL1(awakenBlockedQueueNoLock, \
202 ((StgBlockingQueue *)closure)->blocking_queue);
204 #define AWAKEN_BQ_NOLOCK(info,closure) \
205 if (info == &stg_BLACKHOLE_BQ_info) { \
206 DO_AWAKEN_BQ_NOLOCK(closure); \
209 #endif /* GRAN || PAR */
211 /* -------------------------------------------------------------------------
212 Push an update frame on the stack.
213 ------------------------------------------------------------------------- */
215 #if defined(PROFILING)
216 // frame->header.prof.hp.rs = NULL (or frame-header.prof.hp.ldvw = 0) is unnecessary
217 // because it is not used anyhow.
218 #define PUSH_STD_CCCS(frame) (frame->header.prof.ccs = CCCS)
220 #define PUSH_STD_CCCS(frame)
223 extern DLL_IMPORT_RTS const StgPolyInfoTable stg_upd_frame_info;
224 extern DLL_IMPORT_RTS const StgPolyInfoTable stg_noupd_frame_info;
226 #define PUSH_UPD_FRAME(target, Sp_offset) \
228 StgUpdateFrame *__frame; \
229 TICK_UPDF_PUSHED(target, GET_INFO((StgClosure*)target)); \
230 __frame = (StgUpdateFrame *)(Sp + (Sp_offset)) - 1; \
231 SET_INFO(__frame, (StgInfoTable *)&stg_upd_frame_info); \
232 __frame->updatee = (StgClosure *)(target); \
233 PUSH_STD_CCCS(__frame); \
236 /* -----------------------------------------------------------------------------
239 When a CAF is first entered, it creates a black hole in the heap,
240 and updates itself with an indirection to this new black hole.
242 We update the CAF with an indirection to a newly-allocated black
243 hole in the heap. We also set the blocking queue on the newly
244 allocated black hole to be empty.
246 Why do we make a black hole in the heap when we enter a CAF?
248 - for a generational garbage collector, which needs a fast
249 test for whether an updatee is in an old generation or not
251 - for the parallel system, which can implement updates more
252 easily if the updatee is always in the heap. (allegedly).
254 When debugging, we maintain a separate CAF list so we can tell when
255 a CAF has been garbage collected.
256 -------------------------------------------------------------------------- */
258 /* ToDo: only call newCAF when debugging. */
260 extern void newCAF(StgClosure*);
262 /* newCAF must be called before the itbl ptr is overwritten, since
263 newCAF records the old itbl ptr in order to do CAF reverting
264 (which Hugs needs to do in order that combined mode works right.)
266 #define UPD_CAF(cafptr, bhptr) \
268 LOCK_CLOSURE(cafptr); \
269 STGCALL1(newCAF,(StgClosure *)cafptr); \
270 ((StgInd *)cafptr)->indirectee = (StgClosure *)(bhptr); \
271 SET_INFO((StgInd *)cafptr,(const StgInfoTable*)&stg_IND_STATIC_info);\
274 /* -----------------------------------------------------------------------------
275 Update-related prototypes
276 -------------------------------------------------------------------------- */
278 #endif /* UPDATES_H */