X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2Fsm%2FGC.c;h=0d2ba85860fd36a996af6e69dceff1a820c8e84f;hb=06f9b7c365fb9e9b53723f892b4d63b4f7a56e9a;hp=f248a75a394f8ebbb33177079bb223687dbf1b20;hpb=a84385fa752d8fa800a2155cce95f47c68b74e2b;p=ghc-hetmet.git diff --git a/rts/sm/GC.c b/rts/sm/GC.c index f248a75..0d2ba85 100644 --- a/rts/sm/GC.c +++ b/rts/sm/GC.c @@ -121,6 +121,10 @@ nat mutlist_MUTVARS, gc_thread *gc_threads = NULL; // gc_thread *gct = NULL; // this thread's gct TODO: make thread-local +// Number of threads running in *this* GC. Affects how many +// step->todos[] lists we have to look in to find work. +nat n_gc_threads; + // For stats: long copied; // *words* copied & scavenged during this GC @@ -182,7 +186,6 @@ GarbageCollect ( rtsBool force_major_gc ) step *stp; lnat live, allocated; lnat oldgen_saved_blocks = 0; - nat n_threads; // number of threads participating in GC gc_thread *saved_gct; nat g, s, t; @@ -204,16 +207,11 @@ GarbageCollect ( rtsBool force_major_gc ) } #endif - // tell the STM to discard any cached closures it's hoping to re-use - stmPreGCHook(); - // tell the stats department that we've started a GC stat_startGC(); -#ifdef DEBUG - // check for memory leaks if DEBUG is on - memInventory(); -#endif + // tell the STM to discard any cached closures it's hoping to re-use + stmPreGCHook(); #ifdef DEBUG mutlist_MUTVARS = 0; @@ -249,12 +247,12 @@ GarbageCollect ( rtsBool force_major_gc ) */ #if defined(THREADED_RTS) if (N == 0) { - n_threads = 1; + n_gc_threads = 1; } else { - n_threads = RtsFlags.ParFlags.gcThreads; + n_gc_threads = RtsFlags.ParFlags.gcThreads; } #else - n_threads = 1; + n_gc_threads = 1; #endif #ifdef RTS_GTK_FRONTPANEL @@ -263,6 +261,11 @@ GarbageCollect ( rtsBool force_major_gc ) } #endif +#ifdef DEBUG + // check for memory leaks if DEBUG is on + memInventory(traceClass(DEBUG_gc)); +#endif + // check stack sanity *before* GC (ToDo: check all threads) IF_DEBUG(sanity, checkFreeListSanity()); @@ -279,12 +282,12 @@ GarbageCollect ( rtsBool force_major_gc ) // Initialise all the generations/steps that we're collecting. for (g = 0; g <= N; g++) { - init_collected_gen(g,n_threads); + init_collected_gen(g,n_gc_threads); } // Initialise all the generations/steps that we're *not* collecting. for (g = N+1; g < RtsFlags.GcFlags.generations; g++) { - init_uncollected_gen(g,n_threads); + init_uncollected_gen(g,n_gc_threads); } /* Allocate a mark stack if we're doing a major collection. @@ -299,14 +302,14 @@ GarbageCollect ( rtsBool force_major_gc ) } // Initialise all our gc_thread structures - for (t = 0; t < n_threads; t++) { + for (t = 0; t < n_gc_threads; t++) { init_gc_thread(&gc_threads[t]); } // the main thread is running: this prevents any other threads from // exiting prematurely, so we can start them now. inc_running(); - wakeup_gc_threads(n_threads); + wakeup_gc_threads(n_gc_threads); // Initialise stats copied = 0; @@ -341,6 +344,11 @@ GarbageCollect ( rtsBool force_major_gc ) gct->evac_step = 0; GetRoots(mark_root); +#if defined(RTS_USER_SIGNALS) + // mark the signal handlers (signals should be already blocked) + markSignalHandlers(mark_root); +#endif + // Mark the weak pointer list, and prepare to detect dead weak pointers. markWeakPtrList(); initWeakForGC(); @@ -418,7 +426,7 @@ GarbageCollect ( rtsBool force_major_gc ) step_workspace *ws; bdescr *prev; - for (t = 0; t < n_threads; t++) { + for (t = 0; t < n_gc_threads; t++) { thr = &gc_threads[t]; for (g = 0; g < RtsFlags.GcFlags.generations; g++) { @@ -572,7 +580,9 @@ GarbageCollect ( rtsBool force_major_gc ) resize_generations(); // Guess the amount of live data for stats. - live = calcLive(); + live = calcLiveBlocks() * BLOCK_SIZE_W; + debugTrace(DEBUG_gc, "Slop: %ldKB", + (live - calcLiveWords()) / (1024/sizeof(W_))); // Free the small objects allocated via allocate(), since this will // all have been copied into G0S1 now. @@ -657,7 +667,7 @@ GarbageCollect ( rtsBool force_major_gc ) #ifdef DEBUG // check for memory leaks if DEBUG is on - memInventory(); + memInventory(traceClass(DEBUG_gc)); #endif #ifdef RTS_GTK_FRONTPANEL @@ -681,6 +691,76 @@ GarbageCollect ( rtsBool force_major_gc ) gct = saved_gct; } +/* ----------------------------------------------------------------------------- + * Mark all nodes pointed to by sparks in the spark queues (for GC) Does an + * implicit slide i.e. after marking all sparks are at the beginning of the + * spark pool and the spark pool only contains sparkable closures + * -------------------------------------------------------------------------- */ + +#ifdef THREADED_RTS +static void +markSparkQueue (evac_fn evac, Capability *cap) +{ + StgClosure **sparkp, **to_sparkp; + nat n, pruned_sparks; // stats only + StgSparkPool *pool; + + PAR_TICKY_MARK_SPARK_QUEUE_START(); + + n = 0; + pruned_sparks = 0; + + pool = &(cap->r.rSparks); + + ASSERT_SPARK_POOL_INVARIANTS(pool); + +#if defined(PARALLEL_HASKELL) + // stats only + n = 0; + pruned_sparks = 0; +#endif + + sparkp = pool->hd; + to_sparkp = pool->hd; + while (sparkp != pool->tl) { + ASSERT(*sparkp!=NULL); + ASSERT(LOOKS_LIKE_CLOSURE_PTR(((StgClosure *)*sparkp))); + // ToDo?: statistics gathering here (also for GUM!) + if (closure_SHOULD_SPARK(*sparkp)) { + evac(sparkp); + *to_sparkp++ = *sparkp; + if (to_sparkp == pool->lim) { + to_sparkp = pool->base; + } + n++; + } else { + pruned_sparks++; + } + sparkp++; + if (sparkp == pool->lim) { + sparkp = pool->base; + } + } + pool->tl = to_sparkp; + + PAR_TICKY_MARK_SPARK_QUEUE_END(n); + +#if defined(PARALLEL_HASKELL) + debugTrace(DEBUG_sched, + "marked %d sparks and pruned %d sparks on [%x]", + n, pruned_sparks, mytid); +#else + debugTrace(DEBUG_sched, + "marked %d sparks and pruned %d sparks", + n, pruned_sparks); +#endif + + debugTrace(DEBUG_sched, + "new spark queue len=%d; (hd=%p; tl=%p)\n", + sparkPoolSize(pool), pool->hd, pool->tl); +} +#endif + /* --------------------------------------------------------------------------- Where are the roots that we know about? @@ -692,11 +772,6 @@ GarbageCollect ( rtsBool force_major_gc ) ------------------------------------------------------------------------ */ -/* This has to be protected either by the scheduler monitor, or by the - garbage collection monitor (probably the latter). - KH @ 25/10/99 -*/ - void GetRoots( evac_fn evac ) { @@ -704,7 +779,12 @@ GetRoots( evac_fn evac ) Capability *cap; Task *task; - for (i = 0; i < n_capabilities; i++) { + // Each GC thread is responsible for following roots from the + // Capability of the same number. There will usually be the same + // or fewer Capabilities as GC threads, but just in case there + // are more, we mark every Capability whose number is the GC + // thread's index plus a multiple of the number of GC threads. + for (i = gct->thread_index; i < n_capabilities; i += n_gc_threads) { cap = &capabilities[i]; evac((StgClosure **)(void *)&cap->run_queue_hd); evac((StgClosure **)(void *)&cap->run_queue_tl); @@ -719,6 +799,9 @@ GetRoots( evac_fn evac ) evac((StgClosure **)(void *)&task->suspended_tso); } +#if defined(THREADED_RTS) + markSparkQueue(evac,cap); +#endif } #if !defined(THREADED_RTS) @@ -726,17 +809,6 @@ GetRoots( evac_fn evac ) evac((StgClosure **)(void *)&blocked_queue_tl); evac((StgClosure **)(void *)&sleeping_queue); #endif - - // evac((StgClosure **)&blackhole_queue); - -#if defined(THREADED_RTS) - markSparkQueue(evac); -#endif - -#if defined(RTS_USER_SIGNALS) - // mark the signal handlers (signals should be already blocked) - markSignalHandlers(evac); -#endif } /* ----------------------------------------------------------------------------- @@ -975,6 +1047,10 @@ gc_thread_work (void) // GarbageCollect(), or this is a worker thread and the main // thread bumped gc_running_threads before waking us up. + // Every thread evacuates some roots. + gct->evac_step = 0; + GetRoots(mark_root); + loop: scavenge_loop(); // scavenge_loop() only exits when there's no work to do @@ -1021,14 +1097,14 @@ gc_thread_mainloop (void) if (gct->papi_events == -1) { papi_init_eventset(&gct->papi_events); } - papi_thread_start_gc_count(gct->papi_events); + papi_thread_start_gc1_count(gct->papi_events); #endif gc_thread_work(); #ifdef USE_PAPI // count events in this thread towards the GC totals - papi_thread_stop_gc_count(gct->papi_events); + papi_thread_stop_gc1_count(gct->papi_events); #endif } } @@ -1233,9 +1309,11 @@ init_uncollected_gen (nat g, nat threads) // If the block at the head of the list in this generation // is less than 3/4 full, then use it as a todo block. - if (isPartiallyFull(stp->blocks)) + if (stp->blocks && isPartiallyFull(stp->blocks)) { ws->todo_bd = stp->blocks; + ws->todo_free = ws->todo_bd->free; + ws->todo_lim = ws->todo_bd->start + BLOCK_SIZE_W; stp->blocks = stp->blocks->link; stp->n_blocks -= 1; ws->todo_bd->link = NULL;