*
* ---------------------------------------------------------------------------*/
-// #include "PosixSource.h"
+#include "PosixSource.h"
#include "Rts.h"
-#include "RtsFlags.h"
+#include "HsFFI.h"
+
+#include "Storage.h"
#include "RtsUtils.h"
#include "Apply.h"
-#include "OSThreads.h"
-#include "LdvProfile.h"
#include "Updates.h"
#include "Stats.h"
#include "Schedule.h"
#include "Sanity.h"
#include "BlockAlloc.h"
-#include "MBlock.h"
#include "ProfHeap.h"
-#include "SchedAPI.h"
#include "Weak.h"
#include "Prelude.h"
-#include "ParTicky.h" // ToDo: move into Rts.h
#include "RtsSignals.h"
#include "STM.h"
-#include "HsFFI.h"
-#include "Linker.h"
#if defined(RTS_GTK_FRONTPANEL)
#include "FrontPanel.h"
#endif
#include "Trace.h"
#include "RetainerProfile.h"
+#include "LdvProfile.h"
#include "RaiseAsync.h"
#include "Papi.h"
+#include "Stable.h"
#include "GC.h"
#include "GCThread.h"
#include "Evac.h"
#include "Scav.h"
#include "GCUtils.h"
+#include "MarkStack.h"
#include "MarkWeak.h"
#include "Sparks.h"
#include "Sweep.h"
/* Data used for allocation area sizing.
*/
-static lnat g0s0_pcnt_kept = 30; // percentage of g0s0 live at last minor GC
+static lnat g0_pcnt_kept = 30; // percentage of g0 live at last minor GC
/* Mut-list stats */
#ifdef DEBUG
/* Thread-local data for each GC thread
*/
gc_thread **gc_threads = NULL;
-// gc_thread *gct = NULL; // this thread's gct TODO: make thread-local
+
+#if !defined(THREADED_RTS)
+StgWord8 the_gc_thread[sizeof(gc_thread) + 64 * sizeof(gen_workspace)];
+#endif
// Number of threads running in *this* GC. Affects how many
// step->todos[] lists we have to look in to find work.
static void init_collected_gen (nat g, nat threads);
static void init_uncollected_gen (nat g, nat threads);
static void init_gc_thread (gc_thread *t);
-static void update_task_list (void);
static void resize_generations (void);
static void resize_nursery (void);
static void start_gc_threads (void);
static void scavenge_until_all_done (void);
-static nat inc_running (void);
-static nat dec_running (void);
+static StgWord inc_running (void);
+static StgWord dec_running (void);
static void wakeup_gc_threads (nat n_threads, nat me);
static void shutdown_gc_threads (nat n_threads, nat me);
#endif
/* -----------------------------------------------------------------------------
- The mark bitmap & stack.
+ The mark stack.
-------------------------------------------------------------------------- */
-#define MARK_STACK_BLOCKS 4
-
-bdescr *mark_stack_bdescr;
-StgPtr *mark_stack;
-StgPtr *mark_sp;
-StgPtr *mark_splim;
-
-// Flag and pointers used for falling back to a linear scan when the
-// mark stack overflows.
-rtsBool mark_stack_overflowed;
-bdescr *oldgen_scan_bd;
-StgPtr oldgen_scan;
+bdescr *mark_stack_top_bd; // topmost block in the mark stack
+bdescr *mark_stack_bd; // current block in the mark stack
+StgPtr mark_sp; // pointer to the next unallocated mark stack entry
/* -----------------------------------------------------------------------------
GarbageCollect: the main entry point to the garbage collector.
void
GarbageCollect (rtsBool force_major_gc,
nat gc_type USED_IF_THREADS,
- Capability *cap USED_IF_THREADS)
+ Capability *cap)
{
bdescr *bd;
- step *stp;
+ generation *gen;
lnat live, allocated, max_copied, avg_copied, slop;
gc_thread *saved_gct;
- nat g, s, t, n;
+ nat g, t, n;
// necessary if we stole a callee-saves register for gct:
saved_gct = gct;
}
#endif
- ASSERT(sizeof(step_workspace) == 16 * sizeof(StgWord));
- // otherwise adjust the padding in step_workspace.
+ ASSERT(sizeof(gen_workspace) == 16 * sizeof(StgWord));
+ // otherwise adjust the padding in gen_workspace.
// tell the stats department that we've started a GC
stat_startGC();
// tell the STM to discard any cached closures it's hoping to re-use
stmPreGCHook();
+ // lock the StablePtr table
+ stablePtrPreGC();
+
#ifdef DEBUG
mutlist_MUTVARS = 0;
mutlist_MUTARRS = 0;
n = initialise_N(force_major_gc);
#if defined(THREADED_RTS)
- work_stealing = RtsFlags.ParFlags.parGcLoadBalancing;
+ work_stealing = RtsFlags.ParFlags.parGcLoadBalancingEnabled &&
+ N >= RtsFlags.ParFlags.parGcLoadBalancingGen;
// It's not always a good idea to do load balancing in parallel
// GC. In particular, for a parallel program we don't want to
// lose locality by moving cached data into another CPU's cache
n_gc_threads = 1;
#endif
- trace(TRACE_gc|DEBUG_gc, "GC (gen %d): %d KB to collect, %ld MB in use, using %d thread(s)",
+ debugTrace(DEBUG_gc, "GC (gen %d): %d KB to collect, %ld MB in use, using %d thread(s)",
N, n * (BLOCK_SIZE / 1024), mblocks_allocated, n_gc_threads);
#ifdef RTS_GTK_FRONTPANEL
#ifdef DEBUG
// check for memory leaks if DEBUG is on
- memInventory(traceClass(DEBUG_gc));
+ memInventory(DEBUG_gc);
#endif
- // check stack sanity *before* GC
- IF_DEBUG(sanity, checkFreeListSanity());
- IF_DEBUG(sanity, checkMutableLists(rtsTrue));
+ // check sanity *before* GC
+ IF_DEBUG(sanity, checkSanity(rtsTrue));
// Initialise all our gc_thread structures
for (t = 0; t < n_gc_threads; t++) {
/* Allocate a mark stack if we're doing a major collection.
*/
- if (major_gc && oldest_gen->steps[0].mark) {
- nat mark_stack_blocks;
- mark_stack_blocks = stg_max(MARK_STACK_BLOCKS,
- oldest_gen->steps[0].n_old_blocks / 100);
- mark_stack_bdescr = allocGroup(mark_stack_blocks);
- mark_stack = (StgPtr *)mark_stack_bdescr->start;
- mark_sp = mark_stack;
- mark_splim = mark_stack + (mark_stack_blocks * BLOCK_SIZE_W);
+ if (major_gc && oldest_gen->mark) {
+ mark_stack_bd = allocBlock();
+ mark_stack_top_bd = mark_stack_bd;
+ mark_stack_bd->link = NULL;
+ mark_stack_bd->u.back = NULL;
+ mark_sp = mark_stack_bd->start;
} else {
- mark_stack_bdescr = NULL;
+ mark_stack_bd = NULL;
+ mark_stack_top_bd = NULL;
+ mark_sp = NULL;
}
// this is the main thread
#ifdef THREADED_RTS
if (n_gc_threads == 1) {
- gct = gc_threads[0];
+ SET_GCT(gc_threads[0]);
} else {
- gct = gc_threads[cap->no];
+ SET_GCT(gc_threads[cap->no]);
}
#else
- gct = gc_threads[0];
+SET_GCT(gc_threads[0]);
#endif
/* -----------------------------------------------------------------------
// namely to reduce the likelihood of spurious old->new pointers.
//
for (g = RtsFlags.GcFlags.generations-1; g > N; g--) {
+#if defined(THREADED_RTS)
+ if (n_gc_threads > 1) {
+ scavenge_mutable_list(generations[g].saved_mut_list, &generations[g]);
+ } else {
+ scavenge_mutable_list1(generations[g].saved_mut_list, &generations[g]);
+ }
+#else
scavenge_mutable_list(generations[g].saved_mut_list, &generations[g]);
+#endif
freeChain_sync(generations[g].saved_mut_list);
generations[g].saved_mut_list = NULL;
// variable).
if (n_gc_threads == 1) {
for (n = 0; n < n_capabilities; n++) {
+#if defined(THREADED_RTS)
+ scavenge_capability_mut_Lists1(&capabilities[n]);
+#else
scavenge_capability_mut_lists(&capabilities[n]);
+#endif
}
} else {
scavenge_capability_mut_lists(&capabilities[gct->thread_index]);
}
// follow roots from the CAF list (used by GHCi)
- gct->evac_step = 0;
+ gct->evac_gen = 0;
markCAFs(mark_root, gct);
// follow all the roots that the application knows about.
- gct->evac_step = 0;
+ gct->evac_gen = 0;
markSomeCapabilities(mark_root, gct, gct->thread_index, n_gc_threads,
rtsTrue/*prune sparks*/);
// The other threads are now stopped. We might recurse back to
// here, but from now on this is the only thread.
- // if any blackholes are alive, make the threads that wait on
- // them alive too.
- if (traverseBlackholeQueue()) {
- inc_running();
- continue;
- }
-
// must be last... invariant is that everything is fully
// scavenged at this point.
if (traverseWeakPtrList()) { // returns rtsTrue if evaced something
shutdown_gc_threads(n_gc_threads, gct->thread_index);
- // Update pointers from the Task list
- update_task_list();
-
// Now see which stable names are still alive.
gcStablePtrTable();
// NO MORE EVACUATION AFTER THIS POINT!
// Two-space collector: free the old to-space.
- // g0s0->old_blocks is the old nursery
- // g0s0->blocks is to-space from the previous GC
+ // g0->old_blocks is the old nursery
+ // g0->blocks is to-space from the previous GC
if (RtsFlags.GcFlags.generations == 1) {
- if (g0s0->blocks != NULL) {
- freeChain(g0s0->blocks);
- g0s0->blocks = NULL;
+ if (g0->blocks != NULL) {
+ freeChain(g0->blocks);
+ g0->blocks = NULL;
}
}
// For each workspace, in each thread, move the copied blocks to the step
{
gc_thread *thr;
- step_workspace *ws;
+ gen_workspace *ws;
bdescr *prev, *next;
for (t = 0; t < n_gc_threads; t++) {
thr = gc_threads[t];
- // not step 0
- if (RtsFlags.GcFlags.generations == 1) {
- s = 0;
- } else {
- s = 1;
- }
- for (; s < total_steps; s++) {
- ws = &thr->steps[s];
+ for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
+ ws = &thr->gens[g];
// Push the final block
if (ws->todo_bd) {
prev = NULL;
for (bd = ws->scavd_list; bd != NULL; bd = bd->link) {
- ws->step->n_words += bd->free - bd->start;
+ ws->gen->n_words += bd->free - bd->start;
prev = bd;
}
if (prev != NULL) {
- prev->link = ws->step->blocks;
- ws->step->blocks = ws->scavd_list;
+ prev->link = ws->gen->blocks;
+ ws->gen->blocks = ws->scavd_list;
}
- ws->step->n_blocks += ws->n_scavd_blocks;
+ ws->gen->n_blocks += ws->n_scavd_blocks;
}
}
for (t = 0; t < n_gc_threads; t++) {
thr = gc_threads[t];
- // not step 0
- if (RtsFlags.GcFlags.generations == 1) {
- s = 0;
- } else {
- s = 1;
- }
- for (; s < total_steps; s++) {
- ws = &thr->steps[s];
+ for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
+ ws = &thr->gens[g];
prev = NULL;
for (bd = ws->part_list; bd != NULL; bd = next) {
freeGroup(bd);
ws->n_part_blocks--;
} else {
- ws->step->n_words += bd->free - bd->start;
+ ws->gen->n_words += bd->free - bd->start;
prev = bd;
}
}
if (prev != NULL) {
- prev->link = ws->step->blocks;
- ws->step->blocks = ws->part_list;
+ prev->link = ws->gen->blocks;
+ ws->gen->blocks = ws->part_list;
}
- ws->step->n_blocks += ws->n_part_blocks;
+ ws->gen->n_blocks += ws->n_part_blocks;
- ASSERT(countBlocks(ws->step->blocks) == ws->step->n_blocks);
- ASSERT(countOccupied(ws->step->blocks) == ws->step->n_words);
+ ASSERT(countBlocks(ws->gen->blocks) == ws->gen->n_blocks);
+ ASSERT(countOccupied(ws->gen->blocks) == ws->gen->n_words);
}
}
}
// Finally: compact or sweep the oldest generation.
- if (major_gc && oldest_gen->steps[0].mark) {
- if (oldest_gen->steps[0].compact)
+ if (major_gc && oldest_gen->mark) {
+ if (oldest_gen->compact)
compact(gct->scavenged_static_objects);
else
- sweep(&oldest_gen->steps[0]);
+ sweep(oldest_gen);
}
/* run through all the generations/steps and tidy up
nat i;
for (i=0; i < n_gc_threads; i++) {
if (n_gc_threads > 1) {
- trace(TRACE_gc,"thread %d:", i);
- trace(TRACE_gc," copied %ld", gc_threads[i]->copied * sizeof(W_));
- trace(TRACE_gc," scanned %ld", gc_threads[i]->scanned * sizeof(W_));
- trace(TRACE_gc," any_work %ld", gc_threads[i]->any_work);
- trace(TRACE_gc," no_work %ld", gc_threads[i]->no_work);
- trace(TRACE_gc," scav_find_work %ld", gc_threads[i]->scav_find_work);
+ debugTrace(DEBUG_gc,"thread %d:", i);
+ debugTrace(DEBUG_gc," copied %ld", gc_threads[i]->copied * sizeof(W_));
+ debugTrace(DEBUG_gc," scanned %ld", gc_threads[i]->scanned * sizeof(W_));
+ debugTrace(DEBUG_gc," any_work %ld", gc_threads[i]->any_work);
+ debugTrace(DEBUG_gc," no_work %ld", gc_threads[i]->no_work);
+ debugTrace(DEBUG_gc," scav_find_work %ld", gc_threads[i]->scav_find_work);
}
copied += gc_threads[i]->copied;
max_copied = stg_max(gc_threads[i]->copied, max_copied);
mutlist_MUTVARS, mutlist_MUTARRS, mutlist_MVARS, mutlist_OTHERS);
}
- for (s = 0; s < generations[g].n_steps; s++) {
- bdescr *next, *prev;
- stp = &generations[g].steps[s];
+ bdescr *next, *prev;
+ gen = &generations[g];
- // for generations we collected...
- if (g <= N) {
+ // for generations we collected...
+ if (g <= N) {
/* free old memory and shift to-space into from-space for all
* the collected steps (except the allocation area). These
* freed blocks will probaby be quickly recycled.
*/
- if (!(g == 0 && s == 0 && RtsFlags.GcFlags.generations > 1)) {
- if (stp->mark)
- {
- // tack the new blocks on the end of the existing blocks
- if (stp->old_blocks != NULL) {
-
- prev = NULL;
- for (bd = stp->old_blocks; bd != NULL; bd = next) {
-
- next = bd->link;
-
- if (!(bd->flags & BF_MARKED))
- {
- if (prev == NULL) {
- stp->old_blocks = next;
- } else {
- prev->link = next;
- }
- freeGroup(bd);
- stp->n_old_blocks--;
- }
- else
- {
- stp->n_words += bd->free - bd->start;
-
- // NB. this step might not be compacted next
- // time, so reset the BF_MARKED flags.
- // They are set before GC if we're going to
- // compact. (search for BF_MARKED above).
- bd->flags &= ~BF_MARKED;
-
- // between GCs, all blocks in the heap except
- // for the nursery have the BF_EVACUATED flag set.
- bd->flags |= BF_EVACUATED;
-
- prev = bd;
+ if (gen->mark)
+ {
+ // tack the new blocks on the end of the existing blocks
+ if (gen->old_blocks != NULL) {
+
+ prev = NULL;
+ for (bd = gen->old_blocks; bd != NULL; bd = next) {
+
+ next = bd->link;
+
+ if (!(bd->flags & BF_MARKED))
+ {
+ if (prev == NULL) {
+ gen->old_blocks = next;
+ } else {
+ prev->link = next;
}
- }
-
- if (prev != NULL) {
- prev->link = stp->blocks;
- stp->blocks = stp->old_blocks;
+ freeGroup(bd);
+ gen->n_old_blocks--;
}
- }
- // add the new blocks to the block tally
- stp->n_blocks += stp->n_old_blocks;
- ASSERT(countBlocks(stp->blocks) == stp->n_blocks);
- ASSERT(countOccupied(stp->blocks) == stp->n_words);
- }
- else // not copacted
- {
- freeChain(stp->old_blocks);
- }
- stp->old_blocks = NULL;
- stp->n_old_blocks = 0;
- }
-
- /* LARGE OBJECTS. The current live large objects are chained on
- * scavenged_large, having been moved during garbage
- * collection from large_objects. Any objects left on
- * large_objects list are therefore dead, so we free them here.
- */
- for (bd = stp->large_objects; bd != NULL; bd = next) {
- next = bd->link;
- freeGroup(bd);
- bd = next;
- }
+ else
+ {
+ gen->n_words += bd->free - bd->start;
+
+ // NB. this step might not be compacted next
+ // time, so reset the BF_MARKED flags.
+ // They are set before GC if we're going to
+ // compact. (search for BF_MARKED above).
+ bd->flags &= ~BF_MARKED;
+
+ // between GCs, all blocks in the heap except
+ // for the nursery have the BF_EVACUATED flag set.
+ bd->flags |= BF_EVACUATED;
+
+ prev = bd;
+ }
+ }
- stp->large_objects = stp->scavenged_large_objects;
- stp->n_large_blocks = stp->n_scavenged_large_blocks;
+ if (prev != NULL) {
+ prev->link = gen->blocks;
+ gen->blocks = gen->old_blocks;
+ }
+ }
+ // add the new blocks to the block tally
+ gen->n_blocks += gen->n_old_blocks;
+ ASSERT(countBlocks(gen->blocks) == gen->n_blocks);
+ ASSERT(countOccupied(gen->blocks) == gen->n_words);
+ }
+ else // not copacted
+ {
+ freeChain(gen->old_blocks);
+ }
- }
- else // for older generations...
- {
+ gen->old_blocks = NULL;
+ gen->n_old_blocks = 0;
+
+ /* LARGE OBJECTS. The current live large objects are chained on
+ * scavenged_large, having been moved during garbage
+ * collection from large_objects. Any objects left on the
+ * large_objects list are therefore dead, so we free them here.
+ */
+ freeChain(gen->large_objects);
+ gen->large_objects = gen->scavenged_large_objects;
+ gen->n_large_blocks = gen->n_scavenged_large_blocks;
+ gen->n_new_large_blocks = 0;
+ ASSERT(countBlocks(gen->large_objects) == gen->n_large_blocks);
+ }
+ else // for generations > N
+ {
/* For older generations, we need to append the
* scavenged_large_object list (i.e. large objects that have been
* promoted during this GC) to the large_object list for that step.
*/
- for (bd = stp->scavenged_large_objects; bd; bd = next) {
- next = bd->link;
- dbl_link_onto(bd, &stp->large_objects);
+ for (bd = gen->scavenged_large_objects; bd; bd = next) {
+ next = bd->link;
+ dbl_link_onto(bd, &gen->large_objects);
}
-
+
// add the new blocks we promoted during this GC
- stp->n_large_blocks += stp->n_scavenged_large_blocks;
- }
+ gen->n_large_blocks += gen->n_scavenged_large_blocks;
+ ASSERT(countBlocks(gen->large_objects) == gen->n_large_blocks);
}
- }
+ } // for all generations
// update the max size of older generations after a major GC
resize_generations();
// Free the small objects allocated via allocate(), since this will
// all have been copied into G0S1 now.
- if (RtsFlags.GcFlags.generations > 1) {
- if (g0s0->blocks != NULL) {
- freeChain(g0s0->blocks);
- g0s0->blocks = NULL;
- }
- g0s0->n_blocks = 0;
- g0s0->n_words = 0;
- }
- alloc_blocks = 0;
alloc_blocks_lim = RtsFlags.GcFlags.minAllocAreaSize;
// Start a new pinned_object_block
- pinned_object_block = NULL;
+ for (n = 0; n < n_capabilities; n++) {
+ capabilities[n].pinned_object_block = NULL;
+ }
// Free the mark stack.
- if (mark_stack_bdescr != NULL) {
- freeGroup(mark_stack_bdescr);
+ if (mark_stack_top_bd != NULL) {
+ debugTrace(DEBUG_gc, "mark stack: %d blocks",
+ countBlocks(mark_stack_top_bd));
+ freeChain(mark_stack_top_bd);
}
// Free any bitmaps.
for (g = 0; g <= N; g++) {
- for (s = 0; s < generations[g].n_steps; s++) {
- stp = &generations[g].steps[s];
- if (stp->bitmap != NULL) {
- freeGroup(stp->bitmap);
- stp->bitmap = NULL;
- }
+ gen = &generations[g];
+ if (gen->bitmap != NULL) {
+ freeGroup(gen->bitmap);
+ gen->bitmap = NULL;
}
}
// start any pending finalizers
RELEASE_SM_LOCK;
- scheduleFinalizers(last_free_capability, old_weak_ptr_list);
+ scheduleFinalizers(cap, old_weak_ptr_list);
ACQUIRE_SM_LOCK;
// send exceptions to any threads which were about to die
RELEASE_SM_LOCK;
resurrectThreads(resurrected_threads);
- performPendingThrowTos(exception_threads);
ACQUIRE_SM_LOCK;
// Update the stable pointer hash table.
updateStablePtrTable(major_gc);
- // check sanity after GC
- IF_DEBUG(sanity, checkSanity());
+ // check sanity after GC
+ IF_DEBUG(sanity, checkSanity(rtsTrue));
// extra GC trace info
- if (traceClass(TRACE_gc|DEBUG_gc)) statDescribeGens();
+ IF_DEBUG(gc, statDescribeGens());
#ifdef DEBUG
// symbol-table based profiling
#ifdef DEBUG
// check for memory leaks if DEBUG is on
- memInventory(traceClass(DEBUG_gc));
+ memInventory(DEBUG_gc);
#endif
#ifdef RTS_GTK_FRONTPANEL
slop = calcLiveBlocks() * BLOCK_SIZE_W - live;
stat_endGC(allocated, live, copied, N, max_copied, avg_copied, slop);
+ // unlock the StablePtr table
+ stablePtrPostGC();
+
// Guess which generation we'll collect *next* time
initialise_N(force_major_gc);
RELEASE_SM_LOCK;
- gct = saved_gct;
+ SET_GCT(saved_gct);
}
/* -----------------------------------------------------------------------------
initialise_N (rtsBool force_major_gc)
{
int g;
- nat s, blocks, blocks_total;
+ nat blocks, blocks_total;
blocks = 0;
blocks_total = 0;
}
for (g = RtsFlags.GcFlags.generations - 1; g >= 0; g--) {
- blocks = 0;
- for (s = 0; s < generations[g].n_steps; s++) {
- blocks += generations[g].steps[s].n_words / BLOCK_SIZE_W;
- blocks += generations[g].steps[s].n_large_blocks;
- }
+
+ blocks = generations[g].n_words / BLOCK_SIZE_W
+ + generations[g].n_large_blocks;
+
if (blocks >= generations[g].max_blocks) {
N = stg_max(N,g);
}
#define GC_THREAD_RUNNING 2
#define GC_THREAD_WAITING_TO_CONTINUE 3
-static gc_thread *
-alloc_gc_thread (int n)
+static void
+new_gc_thread (nat n, gc_thread *t)
{
- nat s;
- step_workspace *ws;
- gc_thread *t;
-
- t = stgMallocBytes(sizeof(gc_thread) + total_steps * sizeof(step_workspace),
- "alloc_gc_thread");
+ nat g;
+ gen_workspace *ws;
#ifdef THREADED_RTS
t->id = 0;
t->papi_events = -1;
#endif
- for (s = 0; s < total_steps; s++)
+ for (g = 0; g < RtsFlags.GcFlags.generations; g++)
{
- ws = &t->steps[s];
- ws->step = &all_steps[s];
- ASSERT(s == ws->step->abs_no);
- ws->gct = t;
+ ws = &t->gens[g];
+ ws->gen = &generations[g];
+ ASSERT(g == ws->gen->no);
+ ws->my_gct = t;
ws->todo_bd = NULL;
ws->todo_q = newWSDeque(128);
ws->scavd_list = NULL;
ws->n_scavd_blocks = 0;
}
-
- return t;
}
"alloc_gc_threads");
for (i = 0; i < RtsFlags.ParFlags.nNodes; i++) {
- gc_threads[i] = alloc_gc_thread(i);
+ gc_threads[i] =
+ stgMallocBytes(sizeof(gc_thread) +
+ RtsFlags.GcFlags.generations * sizeof(gen_workspace),
+ "alloc_gc_threads");
+
+ new_gc_thread(i, gc_threads[i]);
}
#else
- gc_threads = stgMallocBytes (sizeof(gc_thread*),
- "alloc_gc_threads");
+ gc_threads = stgMallocBytes (sizeof(gc_thread*),"alloc_gc_threads");
+ gc_threads[0] = gct;
+ new_gc_thread(0,gc_threads[0]);
+#endif
+ }
+}
- gc_threads[0] = alloc_gc_thread(0);
+void
+freeGcThreads (void)
+{
+ nat g;
+ if (gc_threads != NULL) {
+#if defined(THREADED_RTS)
+ nat i;
+ for (i = 0; i < n_capabilities; i++) {
+ for (g = 0; g < RtsFlags.GcFlags.generations; g++)
+ {
+ freeWSDeque(gc_threads[i]->gens[g].todo_q);
+ }
+ stgFree (gc_threads[i]);
+ }
+ stgFree (gc_threads);
+#else
+ for (g = 0; g < RtsFlags.GcFlags.generations; g++)
+ {
+ freeWSDeque(gc_threads[0]->gens[g].todo_q);
+ }
+ stgFree (gc_threads);
#endif
+ gc_threads = NULL;
}
}
Start GC threads
------------------------------------------------------------------------- */
-static nat gc_running_threads;
-
-#if defined(THREADED_RTS)
-static Mutex gc_running_mutex;
-#endif
+static volatile StgWord gc_running_threads;
-static nat
+static StgWord
inc_running (void)
{
- nat n_running;
- ACQUIRE_LOCK(&gc_running_mutex);
- n_running = ++gc_running_threads;
- RELEASE_LOCK(&gc_running_mutex);
- ASSERT(n_running <= n_gc_threads);
- return n_running;
+ StgWord new;
+ new = atomic_inc(&gc_running_threads);
+ ASSERT(new <= n_gc_threads);
+ return new;
}
-static nat
+static StgWord
dec_running (void)
{
- nat n_running;
- ACQUIRE_LOCK(&gc_running_mutex);
- ASSERT(n_gc_threads != 0);
- n_running = --gc_running_threads;
- RELEASE_LOCK(&gc_running_mutex);
- return n_running;
+ ASSERT(gc_running_threads != 0);
+ return atomic_dec(&gc_running_threads);
}
static rtsBool
any_work (void)
{
- int s;
- step_workspace *ws;
+ int g;
+ gen_workspace *ws;
gct->any_work++;
write_barrier();
// scavenge objects in compacted generation
- if (mark_stack_overflowed || oldgen_scan_bd != NULL ||
- (mark_stack_bdescr != NULL && !mark_stack_empty())) {
+ if (mark_stack_bd != NULL && !mark_stack_empty()) {
return rtsTrue;
}
// Check for global work in any step. We don't need to check for
// local work, because we have already exited scavenge_loop(),
// which means there is no local work for this thread.
- for (s = total_steps-1; s >= 0; s--) {
- if (s == 0 && RtsFlags.GcFlags.generations > 1) {
- continue;
- }
- ws = &gct->steps[s];
+ for (g = 0; g < (int)RtsFlags.GcFlags.generations; g++) {
+ ws = &gct->gens[g];
if (ws->todo_large_objects) return rtsTrue;
if (!looksEmptyWSDeque(ws->todo_q)) return rtsTrue;
if (ws->todo_overflow) return rtsTrue;
// look for work to steal
for (n = 0; n < n_gc_threads; n++) {
if (n == gct->thread_index) continue;
- for (s = total_steps-1; s >= 0; s--) {
- ws = &gc_threads[n]->steps[s];
+ for (g = RtsFlags.GcFlags.generations-1; g >= 0; g--) {
+ ws = &gc_threads[n]->gens[g];
if (!looksEmptyWSDeque(ws->todo_q)) return rtsTrue;
}
}
#endif
gct->no_work++;
+#if defined(THREADED_RTS)
+ yieldThread();
+#endif
return rtsFalse;
}
{
nat r;
- debugTrace(DEBUG_gc, "GC thread %d working", gct->thread_index);
loop:
+ traceEventGcWork(&capabilities[gct->thread_index]);
+
#if defined(THREADED_RTS)
if (n_gc_threads > 1) {
scavenge_loop();
// scavenge_loop() only exits when there's no work to do
r = dec_running();
- debugTrace(DEBUG_gc, "GC thread %d idle (%d still running)",
- gct->thread_index, r);
+ traceEventGcIdle(&capabilities[gct->thread_index]);
+
+ debugTrace(DEBUG_gc, "%d GC threads still running", r);
while (gc_running_threads != 0) {
// usleep(1);
// scavenge_loop() to perform any pending work.
}
- // All threads are now stopped
- debugTrace(DEBUG_gc, "GC thread %d finished.", gct->thread_index);
+ traceEventGcDone(&capabilities[gct->thread_index]);
}
#if defined(THREADED_RTS)
void
gcWorkerThread (Capability *cap)
{
- cap->in_gc = rtsTrue;
+ gc_thread *saved_gct;
+
+ // necessary if we stole a callee-saves register for gct:
+ saved_gct = gct;
gct = gc_threads[cap->no];
gct->id = osThreadId();
#endif
// Every thread evacuates some roots.
- gct->evac_step = 0;
+ gct->evac_gen = 0;
markSomeCapabilities(mark_root, gct, gct->thread_index, n_gc_threads,
rtsTrue/*prune sparks*/);
scavenge_capability_mut_lists(&capabilities[gct->thread_index]);
gct->thread_index);
ACQUIRE_SPIN_LOCK(&gct->mut_spin);
debugTrace(DEBUG_gc, "GC thread %d on my way...", gct->thread_index);
+
+ SET_GCT(saved_gct);
}
#endif
+#if defined(THREADED_RTS)
+
void
waitForGcThreads (Capability *cap USED_IF_THREADS)
{
-#if defined(THREADED_RTS)
nat n_threads = RtsFlags.ParFlags.nNodes;
nat me = cap->no;
nat i, j;
prodCapability(&capabilities[i], cap->running_task);
}
}
- for (j=0; j < 10000000; j++) {
+ for (j=0; j < 10; j++) {
retry = rtsFalse;
for (i=0; i < n_threads; i++) {
if (i == me) continue;
}
}
if (!retry) break;
+ yieldThread();
}
}
-#endif
}
+#endif // THREADED_RTS
+
static void
start_gc_threads (void)
{
#if defined(THREADED_RTS)
gc_running_threads = 0;
- initMutex(&gc_running_mutex);
#endif
}
#endif
}
+#if defined(THREADED_RTS)
void
releaseGCThreads (Capability *cap USED_IF_THREADS)
{
-#if defined(THREADED_RTS)
nat n_threads = RtsFlags.ParFlags.nNodes;
nat me = cap->no;
nat i;
ACQUIRE_SPIN_LOCK(&gc_threads[i]->gc_spin);
RELEASE_SPIN_LOCK(&gc_threads[i]->mut_spin);
}
-#endif
}
+#endif
/* ----------------------------------------------------------------------------
Initialise a generation that is to be collected
static void
init_collected_gen (nat g, nat n_threads)
{
- nat s, t, i;
- step_workspace *ws;
- step *stp;
+ nat t, i;
+ gen_workspace *ws;
+ generation *gen;
bdescr *bd;
// Throw away the current mutable list. Invariant: the mutable
}
}
- for (s = 0; s < generations[g].n_steps; s++) {
-
- stp = &generations[g].steps[s];
- ASSERT(stp->gen_no == g);
-
- // we'll construct a new list of threads in this step
- // during GC, throw away the current list.
- stp->old_threads = stp->threads;
- stp->threads = END_TSO_QUEUE;
+ gen = &generations[g];
+ ASSERT(gen->no == g);
+
+ // we'll construct a new list of threads in this step
+ // during GC, throw away the current list.
+ gen->old_threads = gen->threads;
+ gen->threads = END_TSO_QUEUE;
+
+ // deprecate the existing blocks
+ gen->old_blocks = gen->blocks;
+ gen->n_old_blocks = gen->n_blocks;
+ gen->blocks = NULL;
+ gen->n_blocks = 0;
+ gen->n_words = 0;
+ gen->live_estimate = 0;
+
+ // initialise the large object queues.
+ gen->scavenged_large_objects = NULL;
+ gen->n_scavenged_large_blocks = 0;
+
+ // mark the small objects as from-space
+ for (bd = gen->old_blocks; bd; bd = bd->link) {
+ bd->flags &= ~BF_EVACUATED;
+ }
+
+ // mark the large objects as from-space
+ for (bd = gen->large_objects; bd; bd = bd->link) {
+ bd->flags &= ~BF_EVACUATED;
+ }
- // generation 0, step 0 doesn't need to-space
- if (g == 0 && s == 0 && RtsFlags.GcFlags.generations > 1) {
- continue;
- }
+ // for a compacted generation, we need to allocate the bitmap
+ if (gen->mark) {
+ nat bitmap_size; // in bytes
+ bdescr *bitmap_bdescr;
+ StgWord *bitmap;
- // deprecate the existing blocks
- stp->old_blocks = stp->blocks;
- stp->n_old_blocks = stp->n_blocks;
- stp->blocks = NULL;
- stp->n_blocks = 0;
- stp->n_words = 0;
- stp->live_estimate = 0;
-
- // initialise the large object queues.
- stp->scavenged_large_objects = NULL;
- stp->n_scavenged_large_blocks = 0;
-
- // mark the small objects as from-space
- for (bd = stp->old_blocks; bd; bd = bd->link) {
- bd->flags &= ~BF_EVACUATED;
- }
-
- // mark the large objects as from-space
- for (bd = stp->large_objects; bd; bd = bd->link) {
- bd->flags &= ~BF_EVACUATED;
- }
-
- // for a compacted step, we need to allocate the bitmap
- if (stp->mark) {
- nat bitmap_size; // in bytes
- bdescr *bitmap_bdescr;
- StgWord *bitmap;
-
- bitmap_size = stp->n_old_blocks * BLOCK_SIZE / (sizeof(W_)*BITS_PER_BYTE);
-
- if (bitmap_size > 0) {
- bitmap_bdescr = allocGroup((lnat)BLOCK_ROUND_UP(bitmap_size)
- / BLOCK_SIZE);
- stp->bitmap = bitmap_bdescr;
- bitmap = bitmap_bdescr->start;
-
- debugTrace(DEBUG_gc, "bitmap_size: %d, bitmap: %p",
- bitmap_size, bitmap);
-
- // don't forget to fill it with zeros!
- memset(bitmap, 0, bitmap_size);
+ bitmap_size = gen->n_old_blocks * BLOCK_SIZE / (sizeof(W_)*BITS_PER_BYTE);
+
+ if (bitmap_size > 0) {
+ bitmap_bdescr = allocGroup((lnat)BLOCK_ROUND_UP(bitmap_size)
+ / BLOCK_SIZE);
+ gen->bitmap = bitmap_bdescr;
+ bitmap = bitmap_bdescr->start;
+
+ debugTrace(DEBUG_gc, "bitmap_size: %d, bitmap: %p",
+ bitmap_size, bitmap);
+
+ // don't forget to fill it with zeros!
+ memset(bitmap, 0, bitmap_size);
+
+ // For each block in this step, point to its bitmap from the
+ // block descriptor.
+ for (bd=gen->old_blocks; bd != NULL; bd = bd->link) {
+ bd->u.bitmap = bitmap;
+ bitmap += BLOCK_SIZE_W / (sizeof(W_)*BITS_PER_BYTE);
- // For each block in this step, point to its bitmap from the
- // block descriptor.
- for (bd=stp->old_blocks; bd != NULL; bd = bd->link) {
- bd->u.bitmap = bitmap;
- bitmap += BLOCK_SIZE_W / (sizeof(W_)*BITS_PER_BYTE);
-
- // Also at this point we set the BF_MARKED flag
- // for this block. The invariant is that
- // BF_MARKED is always unset, except during GC
- // when it is set on those blocks which will be
- // compacted.
- if (!(bd->flags & BF_FRAGMENTED)) {
- bd->flags |= BF_MARKED;
- }
- }
- }
- }
+ // Also at this point we set the BF_MARKED flag
+ // for this block. The invariant is that
+ // BF_MARKED is always unset, except during GC
+ // when it is set on those blocks which will be
+ // compacted.
+ if (!(bd->flags & BF_FRAGMENTED)) {
+ bd->flags |= BF_MARKED;
+ }
+ }
+ }
}
// For each GC thread, for each step, allocate a "todo" block to
// store evacuated objects to be scavenged, and a block to store
// evacuated objects that do not need to be scavenged.
for (t = 0; t < n_threads; t++) {
- for (s = 0; s < generations[g].n_steps; s++) {
-
- // we don't copy objects into g0s0, unless -G0
- if (g==0 && s==0 && RtsFlags.GcFlags.generations > 1) continue;
-
- ws = &gc_threads[t]->steps[g * RtsFlags.GcFlags.steps + s];
-
- ws->todo_large_objects = NULL;
-
- ws->part_list = NULL;
- ws->n_part_blocks = 0;
-
- // allocate the first to-space block; extra blocks will be
- // chained on as necessary.
- ws->todo_bd = NULL;
- ASSERT(looksEmptyWSDeque(ws->todo_q));
- alloc_todo_block(ws,0);
-
- ws->todo_overflow = NULL;
- ws->n_todo_overflow = 0;
-
- ws->scavd_list = NULL;
- ws->n_scavd_blocks = 0;
- }
+ ws = &gc_threads[t]->gens[g];
+
+ ws->todo_large_objects = NULL;
+
+ ws->part_list = NULL;
+ ws->n_part_blocks = 0;
+
+ // allocate the first to-space block; extra blocks will be
+ // chained on as necessary.
+ ws->todo_bd = NULL;
+ ASSERT(looksEmptyWSDeque(ws->todo_q));
+ alloc_todo_block(ws,0);
+
+ ws->todo_overflow = NULL;
+ ws->n_todo_overflow = 0;
+
+ ws->scavd_list = NULL;
+ ws->n_scavd_blocks = 0;
}
}
static void
init_uncollected_gen (nat g, nat threads)
{
- nat s, t, n;
- step_workspace *ws;
- step *stp;
+ nat t, n;
+ gen_workspace *ws;
+ generation *gen;
bdescr *bd;
// save the current mutable lists for this generation, and
capabilities[n].mut_lists[g] = allocBlock();
}
- for (s = 0; s < generations[g].n_steps; s++) {
- stp = &generations[g].steps[s];
- stp->scavenged_large_objects = NULL;
- stp->n_scavenged_large_blocks = 0;
- }
-
- for (s = 0; s < generations[g].n_steps; s++) {
-
- stp = &generations[g].steps[s];
-
- for (t = 0; t < threads; t++) {
- ws = &gc_threads[t]->steps[g * RtsFlags.GcFlags.steps + s];
-
- ASSERT(looksEmptyWSDeque(ws->todo_q));
- ws->todo_large_objects = NULL;
-
- ws->part_list = NULL;
- ws->n_part_blocks = 0;
+ gen = &generations[g];
- ws->scavd_list = NULL;
- ws->n_scavd_blocks = 0;
+ gen->scavenged_large_objects = NULL;
+ gen->n_scavenged_large_blocks = 0;
- // 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 (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;
- stp->n_words -= ws->todo_bd->free - ws->todo_bd->start;
- ws->todo_bd->link = NULL;
- // we must scan from the current end point.
- ws->todo_bd->u.scan = ws->todo_bd->free;
- }
- else
- {
- ws->todo_bd = NULL;
- alloc_todo_block(ws,0);
- }
- }
-
- // deal out any more partial blocks to the threads' part_lists
- t = 0;
- while (stp->blocks && isPartiallyFull(stp->blocks))
+ for (t = 0; t < threads; t++) {
+ ws = &gc_threads[t]->gens[g];
+
+ ASSERT(looksEmptyWSDeque(ws->todo_q));
+ ws->todo_large_objects = NULL;
+
+ ws->part_list = NULL;
+ ws->n_part_blocks = 0;
+
+ ws->scavd_list = NULL;
+ ws->n_scavd_blocks = 0;
+
+ // 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 (gen->blocks && isPartiallyFull(gen->blocks))
+ {
+ ws->todo_bd = gen->blocks;
+ ws->todo_free = ws->todo_bd->free;
+ ws->todo_lim = ws->todo_bd->start + BLOCK_SIZE_W;
+ gen->blocks = gen->blocks->link;
+ gen->n_blocks -= 1;
+ gen->n_words -= ws->todo_bd->free - ws->todo_bd->start;
+ ws->todo_bd->link = NULL;
+ // we must scan from the current end point.
+ ws->todo_bd->u.scan = ws->todo_bd->free;
+ }
+ else
{
- bd = stp->blocks;
- stp->blocks = bd->link;
- ws = &gc_threads[t]->steps[g * RtsFlags.GcFlags.steps + s];
- bd->link = ws->part_list;
- ws->part_list = bd;
- ws->n_part_blocks += 1;
- bd->u.scan = bd->free;
- stp->n_blocks -= 1;
- stp->n_words -= bd->free - bd->start;
- t++;
- if (t == n_gc_threads) t = 0;
+ ws->todo_bd = NULL;
+ alloc_todo_block(ws,0);
}
}
+
+ // deal out any more partial blocks to the threads' part_lists
+ t = 0;
+ while (gen->blocks && isPartiallyFull(gen->blocks))
+ {
+ bd = gen->blocks;
+ gen->blocks = bd->link;
+ ws = &gc_threads[t]->gens[g];
+ bd->link = ws->part_list;
+ ws->part_list = bd;
+ ws->n_part_blocks += 1;
+ bd->u.scan = bd->free;
+ gen->n_blocks -= 1;
+ gen->n_words -= bd->free - bd->start;
+ t++;
+ if (t == n_gc_threads) t = 0;
+ }
}
/* -----------------------------------------------------------------------------
t->scavenged_static_objects = END_OF_STATIC_LIST;
t->scan_bd = NULL;
t->mut_lists = capabilities[t->thread_index].mut_lists;
- t->evac_step = 0;
+ t->evac_gen = 0;
t->failed_to_evac = rtsFalse;
t->eager_promotion = rtsTrue;
t->thunk_selector_depth = 0;
-------------------------------------------------------------------------- */
static void
-mark_root(void *user, StgClosure **root)
+mark_root(void *user USED_IF_THREADS, StgClosure **root)
{
// we stole a register for gct, but this function is called from
// *outside* the GC where the register variable is not in effect,
// incorrect.
gc_thread *saved_gct;
saved_gct = gct;
- gct = user;
+ SET_GCT(user);
evacuate(root);
- gct = saved_gct;
+ SET_GCT(saved_gct);
}
/* -----------------------------------------------------------------------------
}
/* ----------------------------------------------------------------------------
- Update the pointers from the task list
-
- These are treated as weak pointers because we want to allow a main
- thread to get a BlockedOnDeadMVar exception in the same way as any
- other thread. Note that the threads should all have been retained
- by GC by virtue of being on the all_threads list, we're just
- updating pointers here.
- ------------------------------------------------------------------------- */
-
-static void
-update_task_list (void)
-{
- Task *task;
- StgTSO *tso;
- for (task = all_tasks; task != NULL; task = task->all_link) {
- if (!task->stopped && task->tso) {
- ASSERT(task->tso->bound == task);
- tso = (StgTSO *) isAlive((StgClosure *)task->tso);
- if (tso == NULL) {
- barf("task %p: main thread %d has been GC'd",
-#ifdef THREADED_RTS
- (void *)task->id,
-#else
- (void *)task,
-#endif
- task->tso->id);
- }
- task->tso = tso;
- }
- }
-}
-
-/* ----------------------------------------------------------------------------
Reset the sizes of the older generations when we do a major
collection.
nat gens = RtsFlags.GcFlags.generations;
// live in the oldest generations
- if (oldest_gen->steps[0].live_estimate != 0) {
- words = oldest_gen->steps[0].live_estimate;
+ if (oldest_gen->live_estimate != 0) {
+ words = oldest_gen->live_estimate;
} else {
- words = oldest_gen->steps[0].n_words;
+ words = oldest_gen->n_words;
}
live = (words + BLOCK_SIZE_W - 1) / BLOCK_SIZE_W +
- oldest_gen->steps[0].n_large_blocks;
+ oldest_gen->n_large_blocks;
// default max size for all generations except zero
size = stg_max(live * RtsFlags.GcFlags.oldGenFactor,
RtsFlags.GcFlags.minOldGenSize);
+ if (RtsFlags.GcFlags.heapSizeSuggestionAuto) {
+ RtsFlags.GcFlags.heapSizeSuggestion = size;
+ }
+
// minimum size for generation zero
min_alloc = stg_max((RtsFlags.GcFlags.pcFreeHeap * max) / 200,
RtsFlags.GcFlags.minAllocAreaSize);
if (RtsFlags.GcFlags.generations > 1 &&
(RtsFlags.GcFlags.compact ||
(max > 0 &&
- oldest_gen->steps[0].n_blocks >
+ oldest_gen->n_blocks >
(RtsFlags.GcFlags.compactThreshold * max) / 100))) {
- oldest_gen->steps[0].mark = 1;
- oldest_gen->steps[0].compact = 1;
+ oldest_gen->mark = 1;
+ oldest_gen->compact = 1;
// debugBelch("compaction: on\n", live);
} else {
- oldest_gen->steps[0].mark = 0;
- oldest_gen->steps[0].compact = 0;
+ oldest_gen->mark = 0;
+ oldest_gen->compact = 0;
// debugBelch("compaction: off\n", live);
}
if (RtsFlags.GcFlags.sweep) {
- oldest_gen->steps[0].mark = 1;
+ oldest_gen->mark = 1;
}
// if we're going to go over the maximum heap size, reduce the
heapOverflow();
}
- if (oldest_gen->steps[0].compact) {
+ if (oldest_gen->compact) {
if ( (size + (size - 1) * (gens - 2) * 2) + min_alloc > max ) {
size = (max - min_alloc) / ((gens - 1) * 2 - 1);
}
static void
resize_nursery (void)
{
+ lnat min_nursery = RtsFlags.GcFlags.minAllocAreaSize * n_capabilities;
+
if (RtsFlags.GcFlags.generations == 1)
{ // Two-space collector:
nat blocks;
* performance we get from 3L bytes, reducing to the same
* performance at 2L bytes.
*/
- blocks = g0s0->n_blocks;
+ blocks = generations[0].n_blocks;
if ( RtsFlags.GcFlags.maxHeapSize != 0 &&
blocks * RtsFlags.GcFlags.oldGenFactor * 2 >
else
{
blocks *= RtsFlags.GcFlags.oldGenFactor;
- if (blocks < RtsFlags.GcFlags.minAllocAreaSize)
+ if (blocks < min_nursery)
{
- blocks = RtsFlags.GcFlags.minAllocAreaSize;
+ blocks = min_nursery;
}
}
resizeNurseries(blocks);
/* Guess how much will be live in generation 0 step 0 next time.
* A good approximation is obtained by finding the
- * percentage of g0s0 that was live at the last minor GC.
+ * percentage of g0 that was live at the last minor GC.
*
* We have an accurate figure for the amount of copied data in
* 'copied', but we must convert this to a number of blocks, with
*/
if (N == 0)
{
- g0s0_pcnt_kept = ((copied / (BLOCK_SIZE_W - 10)) * 100)
+ g0_pcnt_kept = ((copied / (BLOCK_SIZE_W - 10)) * 100)
/ countNurseryBlocks();
}
*
* Formula: suggested - needed
* ----------------------------
- * 1 + g0s0_pcnt_kept/100
+ * 1 + g0_pcnt_kept/100
*
* where 'needed' is the amount of memory needed at the next
- * collection for collecting all steps except g0s0.
+ * collection for collecting all gens except g0.
*/
blocks =
(((long)RtsFlags.GcFlags.heapSizeSuggestion - (long)needed) * 100) /
- (100 + (long)g0s0_pcnt_kept);
+ (100 + (long)g0_pcnt_kept);
- if (blocks < (long)RtsFlags.GcFlags.minAllocAreaSize) {
- blocks = RtsFlags.GcFlags.minAllocAreaSize;
+ if (blocks < (long)min_nursery) {
+ blocks = min_nursery;
}
resizeNurseries((nat)blocks);
projects / ghc-hetmet.git / blobdiff