#include "PosixSource.h"
#include "Rts.h"
+
+#include "Storage.h"
#include "RtsUtils.h"
-#include "RtsFlags.h"
#include "Stats.h"
-#include "Hooks.h"
#include "BlockAlloc.h"
-#include "MBlock.h"
#include "Weak.h"
#include "Sanity.h"
#include "Arena.h"
-#include "OSThreads.h"
#include "Capability.h"
-#include "Storage.h"
#include "Schedule.h"
#include "RetainerProfile.h" // for counting memory blocks (memInventory)
#include "OSMem.h"
#include "GC.h"
#include "Evac.h"
-#include <stdlib.h>
#include <string.h>
+#include "ffi.h"
+
/*
* All these globals require sm_mutex to access in THREADED_RTS mode.
*/
StgClosure *revertible_caf_list = NULL;
rtsBool keepCAFs;
-bdescr *pinned_object_block; /* allocate pinned objects into this block */
-nat alloc_blocks; /* number of allocate()d blocks since GC */
-nat alloc_blocks_lim; /* approximate limit on alloc_blocks */
+nat alloc_blocks_lim; /* GC if n_large_blocks in any nursery
+ * reaches this. */
+
+bdescr *exec_block;
generation *generations = NULL; /* all the generations */
generation *g0 = NULL; /* generation 0, for convenience */
generation *oldest_gen = NULL; /* oldest generation, for convenience */
-step *g0s0 = NULL; /* generation 0, step 0, for convenience */
-nat total_steps = 0;
-step *all_steps = NULL; /* single array of steps */
-
-ullong total_allocated = 0; /* total memory allocated during run */
-
-nat n_nurseries = 0; /* == RtsFlags.ParFlags.nNodes, convenience */
-step *nurseries = NULL; /* array of nurseries, >1 only if THREADED_RTS */
+nursery *nurseries = NULL; /* array of nurseries, size == n_capabilities */
#ifdef THREADED_RTS
/*
* simultaneous access by two STG threads.
*/
Mutex sm_mutex;
-/*
- * This mutex is used by atomicModifyMutVar# only
- */
-Mutex atomic_modify_mutvar_mutex;
#endif
-
-/*
- * Forward references
- */
-static void *stgAllocForGMP (size_t size_in_bytes);
-static void *stgReallocForGMP (void *ptr, size_t old_size, size_t new_size);
-static void stgDeallocForGMP (void *ptr, size_t size);
+static void allocNurseries ( void );
static void
-initStep (step *stp, int g, int s)
+initGeneration (generation *gen, int g)
{
- stp->no = s;
- stp->abs_no = RtsFlags.GcFlags.steps * g + s;
- stp->blocks = NULL;
- stp->n_blocks = 0;
- stp->n_words = 0;
- stp->old_blocks = NULL;
- stp->n_old_blocks = 0;
- stp->gen = &generations[g];
- stp->gen_no = g;
- stp->large_objects = NULL;
- stp->n_large_blocks = 0;
- stp->scavenged_large_objects = NULL;
- stp->n_scavenged_large_blocks = 0;
- stp->is_compacted = 0;
- stp->bitmap = NULL;
+ gen->no = g;
+ gen->collections = 0;
+ gen->par_collections = 0;
+ gen->failed_promotions = 0;
+ gen->max_blocks = 0;
+ gen->blocks = NULL;
+ gen->n_blocks = 0;
+ gen->n_words = 0;
+ gen->live_estimate = 0;
+ gen->old_blocks = NULL;
+ gen->n_old_blocks = 0;
+ gen->large_objects = NULL;
+ gen->n_large_blocks = 0;
+ gen->n_new_large_blocks = 0;
+ gen->mut_list = allocBlock();
+ gen->scavenged_large_objects = NULL;
+ gen->n_scavenged_large_blocks = 0;
+ gen->mark = 0;
+ gen->compact = 0;
+ gen->bitmap = NULL;
#ifdef THREADED_RTS
- initSpinLock(&stp->sync_todo);
- initSpinLock(&stp->sync_large_objects);
+ initSpinLock(&gen->sync_large_objects);
#endif
+ gen->threads = END_TSO_QUEUE;
+ gen->old_threads = END_TSO_QUEUE;
}
void
initStorage( void )
{
- nat g, s;
- generation *gen;
+ nat g, n;
if (generations != NULL) {
// multi-init protection
* doing something reasonable.
*/
/* We use the NOT_NULL variant or gcc warns that the test is always true */
- ASSERT(LOOKS_LIKE_INFO_PTR_NOT_NULL(&stg_BLACKHOLE_info));
+ ASSERT(LOOKS_LIKE_INFO_PTR_NOT_NULL((StgWord)&stg_BLOCKING_QUEUE_CLEAN_info));
ASSERT(LOOKS_LIKE_CLOSURE_PTR(&stg_dummy_ret_closure));
ASSERT(!HEAP_ALLOCED(&stg_dummy_ret_closure));
#if defined(THREADED_RTS)
initMutex(&sm_mutex);
- initMutex(&atomic_modify_mutvar_mutex);
#endif
ACQUIRE_SM_LOCK;
* sizeof(struct generation_),
"initStorage: gens");
- /* allocate all the steps into an array. It is important that we do
- it this way, because we need the invariant that two step pointers
- can be directly compared to see which is the oldest.
- Remember that the last generation has only one step. */
- total_steps = 1 + (RtsFlags.GcFlags.generations - 1) * RtsFlags.GcFlags.steps;
- all_steps = stgMallocBytes(total_steps * sizeof(struct step_),
- "initStorage: steps");
-
/* Initialise all generations */
for(g = 0; g < RtsFlags.GcFlags.generations; g++) {
- gen = &generations[g];
- gen->no = g;
- gen->mut_list = allocBlock();
- gen->collections = 0;
- gen->par_collections = 0;
- gen->failed_promotions = 0;
- gen->max_blocks = 0;
+ initGeneration(&generations[g], g);
}
/* A couple of convenience pointers */
g0 = &generations[0];
oldest_gen = &generations[RtsFlags.GcFlags.generations-1];
- /* Allocate step structures in each generation */
- if (RtsFlags.GcFlags.generations > 1) {
- /* Only for multiple-generations */
-
- /* Oldest generation: one step */
- oldest_gen->n_steps = 1;
- oldest_gen->steps = all_steps + (RtsFlags.GcFlags.generations - 1)
- * RtsFlags.GcFlags.steps;
-
- /* set up all except the oldest generation with 2 steps */
- for(g = 0; g < RtsFlags.GcFlags.generations-1; g++) {
- generations[g].n_steps = RtsFlags.GcFlags.steps;
- generations[g].steps = all_steps + g * RtsFlags.GcFlags.steps;
- }
-
- } else {
- /* single generation, i.e. a two-space collector */
- g0->n_steps = 1;
- g0->steps = all_steps;
- }
-
-#ifdef THREADED_RTS
- n_nurseries = n_capabilities;
-#else
- n_nurseries = 1;
-#endif
- nurseries = stgMallocBytes (n_nurseries * sizeof(struct step_),
- "initStorage: nurseries");
-
- /* Initialise all steps */
- for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- for (s = 0; s < generations[g].n_steps; s++) {
- initStep(&generations[g].steps[s], g, s);
- }
- }
-
- for (s = 0; s < n_nurseries; s++) {
- initStep(&nurseries[s], 0, s);
- }
+ nurseries = stgMallocBytes(n_capabilities * sizeof(struct nursery_),
+ "initStorage: nurseries");
/* Set up the destination pointers in each younger gen. step */
for (g = 0; g < RtsFlags.GcFlags.generations-1; g++) {
- for (s = 0; s < generations[g].n_steps-1; s++) {
- generations[g].steps[s].to = &generations[g].steps[s+1];
- }
- generations[g].steps[s].to = &generations[g+1].steps[0];
- }
- oldest_gen->steps[0].to = &oldest_gen->steps[0];
-
- for (s = 0; s < n_nurseries; s++) {
- nurseries[s].to = generations[0].steps[0].to;
+ generations[g].to = &generations[g+1];
}
+ oldest_gen->to = oldest_gen;
/* The oldest generation has one step. */
- if (RtsFlags.GcFlags.compact) {
+ if (RtsFlags.GcFlags.compact || RtsFlags.GcFlags.sweep) {
if (RtsFlags.GcFlags.generations == 1) {
- errorBelch("WARNING: compaction is incompatible with -G1; disabled");
+ errorBelch("WARNING: compact/sweep is incompatible with -G1; disabled");
} else {
- oldest_gen->steps[0].is_compacted = 1;
+ oldest_gen->mark = 1;
+ if (RtsFlags.GcFlags.compact)
+ oldest_gen->compact = 1;
}
}
generations[0].max_blocks = 0;
- g0s0 = &generations[0].steps[0];
/* The allocation area. Policy: keep the allocation area
* small to begin with, even if we have a large suggested heap
allocNurseries();
weak_ptr_list = NULL;
- caf_list = NULL;
- revertible_caf_list = NULL;
+ caf_list = END_OF_STATIC_LIST;
+ revertible_caf_list = END_OF_STATIC_LIST;
/* initialise the allocate() interface */
- alloc_blocks = 0;
alloc_blocks_lim = RtsFlags.GcFlags.minAllocAreaSize;
- /* Tell GNU multi-precision pkg about our custom alloc functions */
- mp_set_memory_functions(stgAllocForGMP, stgReallocForGMP, stgDeallocForGMP);
+ exec_block = NULL;
#ifdef THREADED_RTS
initSpinLock(&gc_alloc_block_sync);
- initSpinLock(&recordMutableGen_sync);
whitehole_spin = 0;
#endif
+ N = 0;
+
+ // allocate a block for each mut list
+ for (n = 0; n < n_capabilities; n++) {
+ for (g = 1; g < RtsFlags.GcFlags.generations; g++) {
+ capabilities[n].mut_lists[g] = allocBlock();
+ }
+ }
+
+ initGcThreads();
+
IF_DEBUG(gc, statDescribeGens());
RELEASE_SM_LOCK;
}
void
-freeStorage (void)
+freeStorage (rtsBool free_heap)
{
- stgFree(g0s0); // frees all the steps
stgFree(generations);
- freeAllMBlocks();
+ if (free_heap) freeAllMBlocks();
#if defined(THREADED_RTS)
closeMutex(&sm_mutex);
- closeMutex(&atomic_modify_mutvar_mutex);
#endif
stgFree(nurseries);
+ freeGcThreads();
}
/* -----------------------------------------------------------------------------
The entry code for every CAF does the following:
- - builds a CAF_BLACKHOLE in the heap
- - pushes an update frame pointing to the CAF_BLACKHOLE
- - invokes UPD_CAF(), which:
- - calls newCaf, below
- - updates the CAF with a static indirection to the CAF_BLACKHOLE
+ - builds a BLACKHOLE in the heap
+ - pushes an update frame pointing to the BLACKHOLE
+ - calls newCaf, below
+ - updates the CAF with a static indirection to the BLACKHOLE
- Why do we build a BLACKHOLE in the heap rather than just updating
+ Why do we build an BLACKHOLE in the heap rather than just updating
the thunk directly? It's so that we only need one kind of update
frame - otherwise we'd need a static version of the update frame too.
newCaf() does the following:
- - it puts the CAF on the oldest generation's mut-once list.
- This is so that we can treat the CAF as a root when collecting
+ - it puts the CAF on the oldest generation's mutable list.
+ This is so that we treat the CAF as a root when collecting
younger generations.
For GHCI, we have additional requirements when dealing with CAFs:
-------------------------------------------------------------------------- */
void
-newCAF(StgClosure* caf)
+newCAF(StgRegTable *reg, StgClosure* caf)
{
- ACQUIRE_SM_LOCK;
-
if(keepCAFs)
{
// HACK:
// do another hack here and do an address range test on caf to figure
// out whether it is from a dynamic library.
((StgIndStatic *)caf)->saved_info = (StgInfoTable *)caf->header.info;
+
+ ACQUIRE_SM_LOCK; // caf_list is global, locked by sm_mutex
((StgIndStatic *)caf)->static_link = caf_list;
caf_list = caf;
+ RELEASE_SM_LOCK;
}
else
{
- /* Put this CAF on the mutable list for the old generation.
- * This is a HACK - the IND_STATIC closure doesn't really have
- * a mut_link field, but we pretend it has - in fact we re-use
- * the STATIC_LINK field for the time being, because when we
- * come to do a major GC we won't need the mut_link field
- * any more and can use it as a STATIC_LINK.
- */
+ // Put this CAF on the mutable list for the old generation.
((StgIndStatic *)caf)->saved_info = NULL;
- recordMutableGen(caf, oldest_gen);
+ if (oldest_gen->no != 0) {
+ recordMutableCap(caf, regTableToCapability(reg), oldest_gen->no);
+ }
}
-
- RELEASE_SM_LOCK;
+}
+
+// External API for setting the keepCAFs flag. see #3900.
+void
+setKeepCAFs (void)
+{
+ keepCAFs = 1;
}
// An alternate version of newCaf which is used for dynamically loaded
// The linker hackily arranges that references to newCaf from dynamic
// code end up pointing to newDynCAF.
void
-newDynCAF(StgClosure *caf)
+newDynCAF (StgRegTable *reg STG_UNUSED, StgClosure *caf)
{
ACQUIRE_SM_LOCK;
-------------------------------------------------------------------------- */
static bdescr *
-allocNursery (step *stp, bdescr *tail, nat blocks)
+allocNursery (bdescr *tail, nat blocks)
{
- bdescr *bd;
- nat i;
+ bdescr *bd = NULL;
+ nat i, n;
+
+ // We allocate the nursery as a single contiguous block and then
+ // divide it into single blocks manually. This way we guarantee
+ // that the nursery blocks are adjacent, so that the processor's
+ // automatic prefetching works across nursery blocks. This is a
+ // tiny optimisation (~0.5%), but it's free.
+
+ while (blocks > 0) {
+ n = stg_min(blocks, BLOCKS_PER_MBLOCK);
+ blocks -= n;
+
+ bd = allocGroup(n);
+ for (i = 0; i < n; i++) {
+ initBdescr(&bd[i], g0, g0);
+
+ bd[i].blocks = 1;
+ bd[i].flags = 0;
+
+ if (i > 0) {
+ bd[i].u.back = &bd[i-1];
+ } else {
+ bd[i].u.back = NULL;
+ }
- // Allocate a nursery: we allocate fresh blocks one at a time and
- // cons them on to the front of the list, not forgetting to update
- // the back pointer on the tail of the list to point to the new block.
- for (i=0; i < blocks; i++) {
- // @LDV profiling
- /*
- processNursery() in LdvProfile.c assumes that every block group in
- the nursery contains only a single block. So, if a block group is
- given multiple blocks, change processNursery() accordingly.
- */
- bd = allocBlock();
- bd->link = tail;
- // double-link the nursery: we might need to insert blocks
- if (tail != NULL) {
- tail->u.back = bd;
- }
- bd->step = stp;
- bd->gen_no = 0;
- bd->flags = 0;
- bd->free = bd->start;
- tail = bd;
+ if (i+1 < n) {
+ bd[i].link = &bd[i+1];
+ } else {
+ bd[i].link = tail;
+ if (tail != NULL) {
+ tail->u.back = &bd[i];
+ }
+ }
+
+ bd[i].free = bd[i].start;
+ }
+
+ tail = &bd[0];
}
- tail->u.back = NULL;
- return tail;
+
+ return &bd[0];
}
static void
assignNurseriesToCapabilities (void)
{
-#ifdef THREADED_RTS
nat i;
- for (i = 0; i < n_nurseries; i++) {
+ for (i = 0; i < n_capabilities; i++) {
capabilities[i].r.rNursery = &nurseries[i];
capabilities[i].r.rCurrentNursery = nurseries[i].blocks;
capabilities[i].r.rCurrentAlloc = NULL;
}
-#else /* THREADED_RTS */
- MainCapability.r.rNursery = &nurseries[0];
- MainCapability.r.rCurrentNursery = nurseries[0].blocks;
- MainCapability.r.rCurrentAlloc = NULL;
-#endif
}
-void
+static void
allocNurseries( void )
{
nat i;
- for (i = 0; i < n_nurseries; i++) {
+ for (i = 0; i < n_capabilities; i++) {
nurseries[i].blocks =
- allocNursery(&nurseries[i], NULL,
- RtsFlags.GcFlags.minAllocAreaSize);
- nurseries[i].n_blocks = RtsFlags.GcFlags.minAllocAreaSize;
- nurseries[i].old_blocks = NULL;
- nurseries[i].n_old_blocks = 0;
+ allocNursery(NULL, RtsFlags.GcFlags.minAllocAreaSize);
+ nurseries[i].n_blocks =
+ RtsFlags.GcFlags.minAllocAreaSize;
}
assignNurseriesToCapabilities();
}
{
nat i;
bdescr *bd;
- step *stp;
- for (i = 0; i < n_nurseries; i++) {
- stp = &nurseries[i];
- for (bd = stp->blocks; bd; bd = bd->link) {
+ for (i = 0; i < n_capabilities; i++) {
+ for (bd = nurseries[i].blocks; bd; bd = bd->link) {
bd->free = bd->start;
ASSERT(bd->gen_no == 0);
- ASSERT(bd->step == stp);
+ ASSERT(bd->gen == g0);
IF_DEBUG(sanity,memset(bd->start, 0xaa, BLOCK_SIZE));
}
}
nat i;
lnat blocks = 0;
- for (i = 0; i < n_nurseries; i++) {
+ for (i = 0; i < n_capabilities; i++) {
blocks += nurseries[i].n_blocks;
}
return blocks;
}
static void
-resizeNursery ( step *stp, nat blocks )
+resizeNursery ( nursery *nursery, nat blocks )
{
bdescr *bd;
nat nursery_blocks;
- nursery_blocks = stp->n_blocks;
+ nursery_blocks = nursery->n_blocks;
if (nursery_blocks == blocks) return;
if (nursery_blocks < blocks) {
debugTrace(DEBUG_gc, "increasing size of nursery to %d blocks",
blocks);
- stp->blocks = allocNursery(stp, stp->blocks, blocks-nursery_blocks);
+ nursery->blocks = allocNursery(nursery->blocks, blocks-nursery_blocks);
}
else {
bdescr *next_bd;
debugTrace(DEBUG_gc, "decreasing size of nursery to %d blocks",
blocks);
- bd = stp->blocks;
+ bd = nursery->blocks;
while (nursery_blocks > blocks) {
next_bd = bd->link;
next_bd->u.back = NULL;
freeGroup(bd);
bd = next_bd;
}
- stp->blocks = bd;
+ nursery->blocks = bd;
// might have gone just under, by freeing a large block, so make
// up the difference.
if (nursery_blocks < blocks) {
- stp->blocks = allocNursery(stp, stp->blocks, blocks-nursery_blocks);
+ nursery->blocks = allocNursery(nursery->blocks, blocks-nursery_blocks);
}
}
- stp->n_blocks = blocks;
- ASSERT(countBlocks(stp->blocks) == stp->n_blocks);
+ nursery->n_blocks = blocks;
+ ASSERT(countBlocks(nursery->blocks) == nursery->n_blocks);
}
//
resizeNurseriesFixed (nat blocks)
{
nat i;
- for (i = 0; i < n_nurseries; i++) {
+ for (i = 0; i < n_capabilities; i++) {
resizeNursery(&nurseries[i], blocks);
}
}
{
// If there are multiple nurseries, then we just divide the number
// of available blocks between them.
- resizeNurseriesFixed(blocks / n_nurseries);
+ resizeNurseriesFixed(blocks / n_capabilities);
}
-/* -----------------------------------------------------------------------------
- The allocate() interface
- allocateInGen() function allocates memory directly into a specific
- generation. It always succeeds, and returns a chunk of memory n
- words long. n can be larger than the size of a block if necessary,
- in which case a contiguous block group will be allocated.
-
- allocate(n) is equivalent to allocateInGen(g0).
+/* -----------------------------------------------------------------------------
+ move_TSO is called to update the TSO structure after it has been
+ moved from one place to another.
-------------------------------------------------------------------------- */
-StgPtr
-allocateInGen (generation *g, nat n)
+void
+move_TSO (StgTSO *src, StgTSO *dest)
{
- step *stp;
- bdescr *bd;
- StgPtr ret;
-
- ACQUIRE_SM_LOCK;
-
- TICK_ALLOC_HEAP_NOCTR(n);
- CCS_ALLOC(CCCS,n);
-
- stp = &g->steps[0];
-
- if (n >= LARGE_OBJECT_THRESHOLD/sizeof(W_))
- {
- nat req_blocks = (lnat)BLOCK_ROUND_UP(n*sizeof(W_)) / BLOCK_SIZE;
-
- // Attempting to allocate an object larger than maxHeapSize
- // should definitely be disallowed. (bug #1791)
- if (RtsFlags.GcFlags.maxHeapSize > 0 &&
- req_blocks >= RtsFlags.GcFlags.maxHeapSize) {
- heapOverflow();
- }
-
- bd = allocGroup(req_blocks);
- dbl_link_onto(bd, &stp->large_objects);
- stp->n_large_blocks += bd->blocks; // might be larger than req_blocks
- bd->gen_no = g->no;
- bd->step = stp;
- bd->flags = BF_LARGE;
- bd->free = bd->start + n;
- ret = bd->start;
- }
- else
- {
- // small allocation (<LARGE_OBJECT_THRESHOLD) */
- bd = stp->blocks;
- if (bd == NULL || bd->free + n > bd->start + BLOCK_SIZE_W) {
- bd = allocBlock();
- bd->gen_no = g->no;
- bd->step = stp;
- bd->flags = 0;
- bd->link = stp->blocks;
- stp->blocks = bd;
- stp->n_blocks++;
- alloc_blocks++;
- }
- ret = bd->free;
- bd->free += n;
- }
+ ptrdiff_t diff;
- RELEASE_SM_LOCK;
-
- return ret;
+ // relocate the stack pointer...
+ diff = (StgPtr)dest - (StgPtr)src; // In *words*
+ dest->sp = (StgPtr)dest->sp + diff;
}
-StgPtr
-allocate (nat n)
-{
- return allocateInGen(g0,n);
-}
-
-lnat
-allocatedBytes( void )
-{
- lnat allocated;
-
- allocated = alloc_blocks * BLOCK_SIZE_W;
- if (pinned_object_block != NULL) {
- allocated -= (pinned_object_block->start + BLOCK_SIZE_W) -
- pinned_object_block->free;
- }
-
- return allocated;
-}
+/* -----------------------------------------------------------------------------
+ split N blocks off the front of the given bdescr, returning the
+ new block group. We add the remainder to the large_blocks list
+ in the same step as the original block.
+ -------------------------------------------------------------------------- */
-// split N blocks off the start of the given bdescr, returning the
-// remainder as a new block group. We treat the remainder as if it
-// had been freshly allocated in generation 0.
bdescr *
splitLargeBlock (bdescr *bd, nat blocks)
{
bdescr *new_bd;
+ ACQUIRE_SM_LOCK;
+
+ ASSERT(countBlocks(bd->gen->large_objects) == bd->gen->n_large_blocks);
+
// subtract the original number of blocks from the counter first
- bd->step->n_large_blocks -= bd->blocks;
+ bd->gen->n_large_blocks -= bd->blocks;
new_bd = splitBlockGroup (bd, blocks);
-
- dbl_link_onto(new_bd, &g0s0->large_objects);
- g0s0->n_large_blocks += new_bd->blocks;
- new_bd->gen_no = g0s0->no;
- new_bd->step = g0s0;
- new_bd->flags = BF_LARGE;
+ initBdescr(new_bd, bd->gen, bd->gen->to);
+ new_bd->flags = BF_LARGE | (bd->flags & BF_EVACUATED);
+ // if new_bd is in an old generation, we have to set BF_EVACUATED
new_bd->free = bd->free;
+ dbl_link_onto(new_bd, &bd->gen->large_objects);
+
+ ASSERT(new_bd->free <= new_bd->start + new_bd->blocks * BLOCK_SIZE_W);
// add the new number of blocks to the counter. Due to the gaps
- // for block descriptor, new_bd->blocks + bd->blocks might not be
+ // for block descriptors, new_bd->blocks + bd->blocks might not be
// equal to the original bd->blocks, which is why we do it this way.
- bd->step->n_large_blocks += bd->blocks;
+ bd->gen->n_large_blocks += bd->blocks + new_bd->blocks;
+
+ ASSERT(countBlocks(bd->gen->large_objects) == bd->gen->n_large_blocks);
+
+ RELEASE_SM_LOCK;
return new_bd;
-}
+}
/* -----------------------------------------------------------------------------
- allocateLocal()
+ allocate()
This allocates memory in the current thread - it is intended for
use primarily from STG-land where we have a Capability. It is
-------------------------------------------------------------------------- */
StgPtr
-allocateLocal (Capability *cap, nat n)
+allocate (Capability *cap, lnat n)
{
bdescr *bd;
StgPtr p;
if (n >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) {
- return allocateInGen(g0,n);
+ lnat req_blocks = (lnat)BLOCK_ROUND_UP(n*sizeof(W_)) / BLOCK_SIZE;
+
+ // Attempting to allocate an object larger than maxHeapSize
+ // should definitely be disallowed. (bug #1791)
+ if (RtsFlags.GcFlags.maxHeapSize > 0 &&
+ req_blocks >= RtsFlags.GcFlags.maxHeapSize) {
+ heapOverflow();
+ // heapOverflow() doesn't exit (see #2592), but we aren't
+ // in a position to do a clean shutdown here: we
+ // either have to allocate the memory or exit now.
+ // Allocating the memory would be bad, because the user
+ // has requested that we not exceed maxHeapSize, so we
+ // just exit.
+ stg_exit(EXIT_HEAPOVERFLOW);
+ }
+
+ ACQUIRE_SM_LOCK
+ bd = allocGroup(req_blocks);
+ dbl_link_onto(bd, &g0->large_objects);
+ g0->n_large_blocks += bd->blocks; // might be larger than req_blocks
+ g0->n_new_large_blocks += bd->blocks;
+ RELEASE_SM_LOCK;
+ initBdescr(bd, g0, g0);
+ bd->flags = BF_LARGE;
+ bd->free = bd->start + n;
+ return bd->start;
}
/* small allocation (<LARGE_OBJECT_THRESHOLD) */
bd = allocBlock();
cap->r.rNursery->n_blocks++;
RELEASE_SM_LOCK;
- bd->gen_no = 0;
- bd->step = cap->r.rNursery;
+ initBdescr(bd, g0, g0);
bd->flags = 0;
- // NO: alloc_blocks++;
- // calcAllocated() uses the size of the nursery, and we've
- // already bumpted nursery->n_blocks above.
+ // If we had to allocate a new block, then we'll GC
+ // pretty quickly now, because MAYBE_GC() will
+ // notice that CurrentNursery->link is NULL.
} else {
// we have a block in the nursery: take it and put
// it at the *front* of the nursery list, and use it
}
p = bd->free;
bd->free += n;
+
+ IF_DEBUG(sanity, ASSERT(*((StgWord8*)p) == 0xaa));
return p;
}
We allocate small pinned objects into a single block, allocating a
new block when the current one overflows. The block is chained
- onto the large_object_list of generation 0 step 0.
+ onto the large_object_list of generation 0.
NOTE: The GC can't in general handle pinned objects. This
interface is only safe to use for ByteArrays, which have no
------------------------------------------------------------------------- */
StgPtr
-allocatePinned( nat n )
+allocatePinned (Capability *cap, lnat n)
{
StgPtr p;
- bdescr *bd = pinned_object_block;
+ bdescr *bd;
// If the request is for a large object, then allocate()
// will give us a pinned object anyway.
if (n >= LARGE_OBJECT_THRESHOLD/sizeof(W_)) {
- return allocate(n);
+ p = allocate(cap, n);
+ Bdescr(p)->flags |= BF_PINNED;
+ return p;
}
- ACQUIRE_SM_LOCK;
-
TICK_ALLOC_HEAP_NOCTR(n);
CCS_ALLOC(CCCS,n);
- // we always return 8-byte aligned memory. bd->free must be
- // 8-byte aligned to begin with, so we just round up n to
- // the nearest multiple of 8 bytes.
- if (sizeof(StgWord) == 4) {
- n = (n+1) & ~1;
- }
-
+ bd = cap->pinned_object_block;
+
// If we don't have a block of pinned objects yet, or the current
// one isn't large enough to hold the new object, allocate a new one.
if (bd == NULL || (bd->free + n) > (bd->start + BLOCK_SIZE_W)) {
- pinned_object_block = bd = allocBlock();
- dbl_link_onto(bd, &g0s0->large_objects);
- g0s0->n_large_blocks++;
- bd->gen_no = 0;
- bd->step = g0s0;
+ ACQUIRE_SM_LOCK;
+ cap->pinned_object_block = bd = allocBlock();
+ dbl_link_onto(bd, &g0->large_objects);
+ g0->n_large_blocks++;
+ g0->n_new_large_blocks++;
+ RELEASE_SM_LOCK;
+ initBdescr(bd, g0, g0);
bd->flags = BF_PINNED | BF_LARGE;
bd->free = bd->start;
- alloc_blocks++;
}
p = bd->free;
bd->free += n;
- RELEASE_SM_LOCK;
return p;
}
dirty_MUT_VAR(StgRegTable *reg, StgClosure *p)
{
Capability *cap = regTableToCapability(reg);
- bdescr *bd;
if (p->header.info == &stg_MUT_VAR_CLEAN_info) {
p->header.info = &stg_MUT_VAR_DIRTY_info;
- bd = Bdescr((StgPtr)p);
- if (bd->gen_no > 0) recordMutableCap(p,cap,bd->gen_no);
+ recordClosureMutated(cap,p);
}
}
void
setTSOLink (Capability *cap, StgTSO *tso, StgTSO *target)
{
- bdescr *bd;
- if ((tso->flags & (TSO_DIRTY|TSO_LINK_DIRTY)) == 0) {
+ if (tso->dirty == 0 && (tso->flags & TSO_LINK_DIRTY) == 0) {
tso->flags |= TSO_LINK_DIRTY;
- bd = Bdescr((StgPtr)tso);
- if (bd->gen_no > 0) recordMutableCap((StgClosure*)tso,cap,bd->gen_no);
+ recordClosureMutated(cap,(StgClosure*)tso);
}
tso->_link = target;
}
void
+setTSOPrev (Capability *cap, StgTSO *tso, StgTSO *target)
+{
+ if (tso->dirty == 0 && (tso->flags & TSO_LINK_DIRTY) == 0) {
+ tso->flags |= TSO_LINK_DIRTY;
+ recordClosureMutated(cap,(StgClosure*)tso);
+ }
+ tso->block_info.prev = target;
+}
+
+void
dirty_TSO (Capability *cap, StgTSO *tso)
{
- bdescr *bd;
- if ((tso->flags & TSO_DIRTY) == 0) {
- tso->flags |= TSO_DIRTY;
- bd = Bdescr((StgPtr)tso);
- if (bd->gen_no > 0) recordMutableCap((StgClosure*)tso,cap,bd->gen_no);
+ if (tso->dirty == 0 && (tso->flags & TSO_LINK_DIRTY) == 0) {
+ recordClosureMutated(cap,(StgClosure*)tso);
}
+ tso->dirty = 1;
}
/*
void
dirty_MVAR(StgRegTable *reg, StgClosure *p)
{
- Capability *cap = regTableToCapability(reg);
- bdescr *bd;
- bd = Bdescr((StgPtr)p);
- if (bd->gen_no > 0) recordMutableCap(p,cap,bd->gen_no);
-}
-
-/* -----------------------------------------------------------------------------
- Allocation functions for GMP.
-
- These all use the allocate() interface - we can't have any garbage
- collection going on during a gmp operation, so we use allocate()
- which always succeeds. The gmp operations which might need to
- allocate will ask the storage manager (via doYouWantToGC()) whether
- a garbage collection is required, in case we get into a loop doing
- only allocate() style allocation.
- -------------------------------------------------------------------------- */
-
-static void *
-stgAllocForGMP (size_t size_in_bytes)
-{
- StgArrWords* arr;
- nat data_size_in_words, total_size_in_words;
-
- /* round up to a whole number of words */
- data_size_in_words = (size_in_bytes + sizeof(W_) + 1) / sizeof(W_);
- total_size_in_words = sizeofW(StgArrWords) + data_size_in_words;
-
- /* allocate and fill it in. */
-#if defined(THREADED_RTS)
- arr = (StgArrWords *)allocateLocal(myTask()->cap, total_size_in_words);
-#else
- arr = (StgArrWords *)allocateLocal(&MainCapability, total_size_in_words);
-#endif
- SET_ARR_HDR(arr, &stg_ARR_WORDS_info, CCCS, data_size_in_words);
-
- /* and return a ptr to the goods inside the array */
- return arr->payload;
-}
-
-static void *
-stgReallocForGMP (void *ptr, size_t old_size, size_t new_size)
-{
- void *new_stuff_ptr = stgAllocForGMP(new_size);
- nat i = 0;
- char *p = (char *) ptr;
- char *q = (char *) new_stuff_ptr;
-
- for (; i < old_size; i++, p++, q++) {
- *q = *p;
- }
-
- return(new_stuff_ptr);
-}
-
-static void
-stgDeallocForGMP (void *ptr STG_UNUSED,
- size_t size STG_UNUSED)
-{
- /* easy for us: the garbage collector does the dealloc'n */
+ recordClosureMutated(regTableToCapability(reg),p);
}
/* -----------------------------------------------------------------------------
*
* Approximate how much we've allocated: number of blocks in the
* nursery + blocks allocated via allocate() - unused nusery blocks.
- * This leaves a little slop at the end of each block, and doesn't
- * take into account large objects (ToDo).
+ * This leaves a little slop at the end of each block.
* -------------------------------------------------------------------------- */
lnat
{
nat allocated;
bdescr *bd;
+ nat i;
- allocated = allocatedBytes();
- allocated += countNurseryBlocks() * BLOCK_SIZE_W;
+ allocated = countNurseryBlocks() * BLOCK_SIZE_W;
- {
-#ifdef THREADED_RTS
- nat i;
- for (i = 0; i < n_nurseries; i++) {
+ for (i = 0; i < n_capabilities; i++) {
Capability *cap;
for ( bd = capabilities[i].r.rCurrentNursery->link;
bd != NULL; bd = bd->link ) {
allocated -= (cap->r.rCurrentNursery->start + BLOCK_SIZE_W)
- cap->r.rCurrentNursery->free;
}
+ if (cap->pinned_object_block != NULL) {
+ allocated -= (cap->pinned_object_block->start + BLOCK_SIZE_W) -
+ cap->pinned_object_block->free;
+ }
}
-#else
- bdescr *current_nursery = MainCapability.r.rCurrentNursery;
- for ( bd = current_nursery->link; bd != NULL; bd = bd->link ) {
- allocated -= BLOCK_SIZE_W;
- }
- if (current_nursery->free < current_nursery->start + BLOCK_SIZE_W) {
- allocated -= (current_nursery->start + BLOCK_SIZE_W)
- - current_nursery->free;
- }
-#endif
- }
+ allocated += g0->n_new_large_blocks * BLOCK_SIZE_W;
- total_allocated += allocated;
return allocated;
}
/* Approximate the amount of live data in the heap. To be called just
* after garbage collection (see GarbageCollect()).
*/
-lnat
-calcLiveBlocks(void)
+lnat calcLiveBlocks (void)
{
- nat g, s;
+ nat g;
lnat live = 0;
- step *stp;
-
- if (RtsFlags.GcFlags.generations == 1) {
- return g0s0->n_large_blocks + g0s0->n_blocks;
- }
+ generation *gen;
for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- for (s = 0; s < generations[g].n_steps; s++) {
/* approximate amount of live data (doesn't take into account slop
* at end of each block).
*/
- if (g == 0 && s == 0) {
- continue;
- }
- stp = &generations[g].steps[s];
- live += stp->n_large_blocks + stp->n_blocks;
- }
+ gen = &generations[g];
+ live += gen->n_large_blocks + gen->n_blocks;
}
return live;
}
-lnat
-countOccupied(bdescr *bd)
+lnat countOccupied (bdescr *bd)
{
lnat words;
words = 0;
for (; bd != NULL; bd = bd->link) {
+ ASSERT(bd->free <= bd->start + bd->blocks * BLOCK_SIZE_W);
words += bd->free - bd->start;
}
return words;
// Return an accurate count of the live data in the heap, excluding
// generation 0.
-lnat
-calcLiveWords(void)
+lnat calcLiveWords (void)
{
- nat g, s;
+ nat g;
lnat live;
- step *stp;
-
- if (RtsFlags.GcFlags.generations == 1) {
- return g0s0->n_words + countOccupied(g0s0->large_objects);
- }
+ generation *gen;
live = 0;
for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- for (s = 0; s < generations[g].n_steps; s++) {
- if (g == 0 && s == 0) continue;
- stp = &generations[g].steps[s];
- live += stp->n_words + countOccupied(stp->large_objects);
- }
+ gen = &generations[g];
+ live += gen->n_words + countOccupied(gen->large_objects);
}
return live;
}
/* Approximate the number of blocks that will be needed at the next
* garbage collection.
*
- * Assume: all data currently live will remain live. Steps that will
- * be collected next time will therefore need twice as many blocks
- * since all the data will be copied.
+ * Assume: all data currently live will remain live. Generationss
+ * that will be collected next time will therefore need twice as many
+ * blocks since all the data will be copied.
*/
extern lnat
calcNeeded(void)
{
lnat needed = 0;
- nat g, s;
- step *stp;
+ nat g;
+ generation *gen;
for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- for (s = 0; s < generations[g].n_steps; s++) {
- if (g == 0 && s == 0) { continue; }
- stp = &generations[g].steps[s];
- if (g == 0 || // always collect gen 0
- (generations[g].steps[0].n_blocks +
- generations[g].steps[0].n_large_blocks
- > generations[g].max_blocks
- && stp->is_compacted == 0)) {
- needed += 2 * stp->n_blocks + stp->n_large_blocks;
- } else {
- needed += stp->n_blocks + stp->n_large_blocks;
- }
- }
+ gen = &generations[g];
+
+ // we need at least this much space
+ needed += gen->n_blocks + gen->n_large_blocks;
+
+ // any additional space needed to collect this gen next time?
+ if (g == 0 || // always collect gen 0
+ (gen->n_blocks + gen->n_large_blocks > gen->max_blocks)) {
+ // we will collect this gen next time
+ if (gen->mark) {
+ // bitmap:
+ needed += gen->n_blocks / BITS_IN(W_);
+ // mark stack:
+ needed += gen->n_blocks / 100;
+ }
+ if (gen->compact) {
+ continue; // no additional space needed for compaction
+ } else {
+ needed += gen->n_blocks;
+ }
+ }
}
return needed;
}
should be modified to use allocateExec instead of VirtualAlloc.
------------------------------------------------------------------------- */
-static bdescr *exec_block;
+#if defined(linux_HOST_OS)
+
+// On Linux we need to use libffi for allocating executable memory,
+// because it knows how to work around the restrictions put in place
+// by SELinux.
+
+void *allocateExec (nat bytes, void **exec_ret)
+{
+ void **ret, **exec;
+ ACQUIRE_SM_LOCK;
+ ret = ffi_closure_alloc (sizeof(void *) + (size_t)bytes, (void**)&exec);
+ RELEASE_SM_LOCK;
+ if (ret == NULL) return ret;
+ *ret = ret; // save the address of the writable mapping, for freeExec().
+ *exec_ret = exec + 1;
+ return (ret + 1);
+}
+
+// freeExec gets passed the executable address, not the writable address.
+void freeExec (void *addr)
+{
+ void *writable;
+ writable = *((void**)addr - 1);
+ ACQUIRE_SM_LOCK;
+ ffi_closure_free (writable);
+ RELEASE_SM_LOCK
+}
+
+#else
-void *allocateExec (nat bytes)
+void *allocateExec (nat bytes, void **exec_ret)
{
void *ret;
nat n;
exec_block->free += n + 1;
RELEASE_SM_LOCK
+ *exec_ret = ret;
return ret;
}
RELEASE_SM_LOCK
}
-/* -----------------------------------------------------------------------------
- Debugging
-
- memInventory() checks for memory leaks by counting up all the
- blocks we know about and comparing that to the number of blocks
- allegedly floating around in the system.
- -------------------------------------------------------------------------- */
+#endif /* mingw32_HOST_OS */
#ifdef DEBUG
-// Useful for finding partially full blocks in gdb
-void findSlop(bdescr *bd);
-void findSlop(bdescr *bd)
-{
- lnat slop;
-
- for (; bd != NULL; bd = bd->link) {
- slop = (bd->blocks * BLOCK_SIZE_W) - (bd->free - bd->start);
- if (slop > (1024/sizeof(W_))) {
- debugBelch("block at %p (bdescr %p) has %ldKB slop\n",
- bd->start, bd, slop / (1024/sizeof(W_)));
- }
- }
-}
-
-nat
-countBlocks(bdescr *bd)
-{
- nat n;
- for (n=0; bd != NULL; bd=bd->link) {
- n += bd->blocks;
- }
- return n;
-}
-
-// (*1) Just like countBlocks, except that we adjust the count for a
-// megablock group so that it doesn't include the extra few blocks
-// that would be taken up by block descriptors in the second and
-// subsequent megablock. This is so we can tally the count with the
-// number of blocks allocated in the system, for memInventory().
-static nat
-countAllocdBlocks(bdescr *bd)
-{
- nat n;
- for (n=0; bd != NULL; bd=bd->link) {
- n += bd->blocks;
- // hack for megablock groups: see (*1) above
- if (bd->blocks > BLOCKS_PER_MBLOCK) {
- n -= (MBLOCK_SIZE / BLOCK_SIZE - BLOCKS_PER_MBLOCK)
- * (bd->blocks/(MBLOCK_SIZE/BLOCK_SIZE));
- }
- }
- return n;
-}
-
-static lnat
-stepBlocks (step *stp)
-{
- ASSERT(countBlocks(stp->blocks) == stp->n_blocks);
- ASSERT(countBlocks(stp->large_objects) == stp->n_large_blocks);
- return stp->n_blocks + stp->n_old_blocks +
- countAllocdBlocks(stp->large_objects);
-}
-
-void
-memInventory (rtsBool show)
-{
- nat g, s, i;
- step *stp;
- lnat gen_blocks[RtsFlags.GcFlags.generations];
- lnat nursery_blocks, retainer_blocks,
- arena_blocks, exec_blocks;
- lnat live_blocks = 0, free_blocks = 0;
- rtsBool leak;
-
- // count the blocks we current have
-
- for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- gen_blocks[g] = 0;
- for (i = 0; i < n_capabilities; i++) {
- gen_blocks[g] += countBlocks(capabilities[i].mut_lists[g]);
- }
- gen_blocks[g] += countAllocdBlocks(generations[g].mut_list);
- for (s = 0; s < generations[g].n_steps; s++) {
- stp = &generations[g].steps[s];
- gen_blocks[g] += stepBlocks(stp);
- }
- }
-
- nursery_blocks = 0;
- for (i = 0; i < n_nurseries; i++) {
- nursery_blocks += stepBlocks(&nurseries[i]);
- }
-
- retainer_blocks = 0;
-#ifdef PROFILING
- if (RtsFlags.ProfFlags.doHeapProfile == HEAP_BY_RETAINER) {
- retainer_blocks = retainerStackBlocks();
- }
-#endif
-
- // count the blocks allocated by the arena allocator
- arena_blocks = arenaBlocks();
-
- // count the blocks containing executable memory
- exec_blocks = countAllocdBlocks(exec_block);
-
- /* count the blocks on the free list */
- free_blocks = countFreeList();
-
- live_blocks = 0;
- for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- live_blocks += gen_blocks[g];
- }
- live_blocks += nursery_blocks +
- + retainer_blocks + arena_blocks + exec_blocks;
-
-#define MB(n) (((n) * BLOCK_SIZE_W) / ((1024*1024)/sizeof(W_)))
-
- leak = live_blocks + free_blocks != mblocks_allocated * BLOCKS_PER_MBLOCK;
- if (show || leak)
- {
- if (leak) {
- debugBelch("Memory leak detected:\n");
- } else {
- debugBelch("Memory inventory:\n");
- }
- for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- debugBelch(" gen %d blocks : %5lu blocks (%lu MB)\n", g,
- gen_blocks[g], MB(gen_blocks[g]));
- }
- debugBelch(" nursery : %5lu blocks (%lu MB)\n",
- nursery_blocks, MB(nursery_blocks));
- debugBelch(" retainer : %5lu blocks (%lu MB)\n",
- retainer_blocks, MB(retainer_blocks));
- debugBelch(" arena blocks : %5lu blocks (%lu MB)\n",
- arena_blocks, MB(arena_blocks));
- debugBelch(" exec : %5lu blocks (%lu MB)\n",
- exec_blocks, MB(exec_blocks));
- debugBelch(" free : %5lu blocks (%lu MB)\n",
- free_blocks, MB(free_blocks));
- debugBelch(" total : %5lu blocks (%lu MB)\n",
- live_blocks + free_blocks, MB(live_blocks+free_blocks));
- if (leak) {
- debugBelch("\n in system : %5lu blocks (%lu MB)\n",
- mblocks_allocated * BLOCKS_PER_MBLOCK, mblocks_allocated);
- }
- }
-}
-
-
-/* Full heap sanity check. */
-void
-checkSanity( void )
-{
- nat g, s;
-
- if (RtsFlags.GcFlags.generations == 1) {
- checkHeap(g0s0->blocks);
- checkChain(g0s0->large_objects);
- } else {
-
- for (g = 0; g < RtsFlags.GcFlags.generations; g++) {
- for (s = 0; s < generations[g].n_steps; s++) {
- if (g == 0 && s == 0) { continue; }
- ASSERT(countBlocks(generations[g].steps[s].blocks)
- == generations[g].steps[s].n_blocks);
- ASSERT(countBlocks(generations[g].steps[s].large_objects)
- == generations[g].steps[s].n_large_blocks);
- checkHeap(generations[g].steps[s].blocks);
- checkChain(generations[g].steps[s].large_objects);
- if (g > 0) {
- checkMutableList(generations[g].mut_list, g);
- }
- }
- }
-
- for (s = 0; s < n_nurseries; s++) {
- ASSERT(countBlocks(nurseries[s].blocks)
- == nurseries[s].n_blocks);
- ASSERT(countBlocks(nurseries[s].large_objects)
- == nurseries[s].n_large_blocks);
- }
-
- checkFreeListSanity();
- }
-}
-
-/* Nursery sanity check */
-void
-checkNurserySanity( step *stp )
-{
- bdescr *bd, *prev;
- nat blocks = 0;
-
- prev = NULL;
- for (bd = stp->blocks; bd != NULL; bd = bd->link) {
- ASSERT(bd->u.back == prev);
- prev = bd;
- blocks += bd->blocks;
- }
- ASSERT(blocks == stp->n_blocks);
-}
-
// handy function for use in gdb, because Bdescr() is inlined.
extern bdescr *_bdescr( StgPtr p );