/* poolamc.c: AUTOMATIC MOSTLY-COPYING MEMORY POOL CLASS
*
* $Id: //info.ravenbrook.com/project/mps/version/1.109/code/poolamc.c#1 $
* Copyright (c) 2001 Ravenbrook Limited. See end of file for license.
* Portions copyright (C) 2002 Global Graphics Software.
*
* .sources: <design/poolamc/>.
*/
#include "mpscamc.h"
#include "chain.h"
#include "bt.h"
#include "mpm.h"
SRCID(poolamc, "$Id: //info.ravenbrook.com/project/mps/version/1.109/code/poolamc.c#1 $");
/* PType enumeration -- distinguishes AMCGen and AMCNailboard */
enum {AMCPTypeGen = 1, AMCPTypeNailboard};
/* AMC typedef */
typedef struct AMCStruct *AMC;
/* amcGen typedef */
typedef struct amcGenStruct *amcGen;
/* forward declarations */
static Bool amcSegHasNailboard(Seg seg);
static Bool AMCCheck(AMC amc);
static Res AMCFix(Pool pool, ScanState ss, Seg seg, Ref *refIO);
static Res AMCHeaderFix(Pool pool, ScanState ss, Seg seg, Ref *refIO);
static PoolClass AMCPoolClassGet(void);
static BufferClass amcBufClassGet(void);
static SegClass amcSegClassGet(void);
/* amcGenStruct -- pool AMC generation descriptor */
#define amcGenSig ((Sig)0x519A3C9E) /* SIGnature AMC GEn */
typedef struct amcGenStruct {
PoolGenStruct pgen;
int type; /* AMCPTypeGen for a gen */
RingStruct amcRing; /* link in list of gens in pool */
Buffer forward; /* forwarding buffer */
Count segs; /* number of segs in gen */
Sig sig; /* <code/misc.h#sig> */
} amcGenStruct;
#define amcGenAMC(amcgen) Pool2AMC((amcgen)->pgen.pool)
#define amcGenPool(amcgen) ((amcgen)->pgen.pool)
#define amcGenNr(amcgen) ((amcgen)->pgen.nr)
#define RAMP_RELATION(X) \
X(RampOUTSIDE, "outside ramp") \
X(RampBEGIN, "begin ramp") \
X(RampRAMPING, "ramping") \
X(RampFINISH, "finish ramp") \
X(RampCOLLECTING, "collecting ramp")
#define RAMP_ENUM(e, s) e,
enum {
RAMP_RELATION(RAMP_ENUM)
RampLIMIT
};
#undef RAMP_ENUM
/* amcNailboard -- the nailboard */
typedef struct amcNailboardStruct *amcNailboard;
typedef struct amcNailboardStruct {
Sig sig;
int type; /* AMCPTypeNailboard for a nailboard */
amcGen gen; /* generation of this segment */
Count nails; /* no. of ambigFixes, not necessarily distinct */
Count distinctNails; /* number of distinct ambigFixes */
Bool newMarks; /* set to TRUE if a new mark bit is added */
Shift markShift; /* to convert offset into bit index for mark */
BT mark; /* mark table used to record ambiguous fixes */
} amcNailboardStruct;
#define amcNailboardSig ((Sig)0x519A3C4B) /* SIGnature AMC Nailboard */
/* amcSegStruct -- AMC-specific fields appended to GCSegStruct
*
* .segtype: logically, AMC segs should have pointers to:
* - the generation (amcGenStruct);
* - the nailboard (or NULL if not present).
* But in fact (apparently to save space in the amcSegStruct?) these
* pointers are encoded, so as to use only a single-word "segTypeP"
* field in amcSegStruct, as follows:
* The "segTypeP" field is a pointer to (the type field of) either
* a nailboard or a generation. The value stored in the type field
* indicates whether its enclosing struct is a generation or a
* nailboard. The segTypeP field is initialised by passing an
* additional parameter (the address of the segment's generation) to
* SegAlloc. See <design/poolamc/#fix.nail.distinguish>.
*
* .seg-ramp-new: "new" (if true) means this segment was allocated by
* AMCBufferFill while amc->rampMode == RampRAMPING, and therefore
* (I think) the contribution it *should* make to gen->pgen.newSize
* is being deferred until the ramping is over. "new" is set to FALSE
* in all other (ie. normal) circumstances. (The original comment for
* this struct member was "allocated since last GC"). RHSK 2009-04-15.
*/
typedef struct amcSegStruct *amcSeg;
#define amcSegSig ((Sig)0x519A3C59) /* SIGnature AMC SeG */
typedef struct amcSegStruct {
GCSegStruct gcSegStruct; /* superclass fields must come first */
int *segTypeP; /* .segtype */
Bool new; /* .seg-ramp-new */
Sig sig; /* <code/misc.h#sig> */
} amcSegStruct;
#define Seg2amcSeg(seg) ((amcSeg)(seg))
#define amcSeg2Seg(amcseg) ((Seg)(amcseg))
#define amcSegTypeP(seg) (Seg2amcSeg(seg)->segTypeP)
#define amcSegSetTypeP(seg, type) (Seg2amcSeg(seg)->segTypeP = (type))
static Bool amcSegCheck(amcSeg amcseg)
{
CHECKS(amcSeg, amcseg);
CHECKD(GCSeg, &amcseg->gcSegStruct);
CHECKL(*amcseg->segTypeP == AMCPTypeNailboard
|| *amcseg->segTypeP == AMCPTypeGen);
if(*amcseg->segTypeP == AMCPTypeNailboard) {
CHECKL(SegNailed(amcSeg2Seg(amcseg)) != TraceSetEMPTY);
}
CHECKL(BoolCheck(amcseg->new));
return TRUE;
}
/* AMCSegInit -- initialise an AMC segment */
static Res AMCSegInit(Seg seg, Pool pool, Addr base, Size size,
Bool reservoirPermit, va_list args)
{
int *segtype = va_arg(args, int*); /* .segtype */
SegClass super;
amcSeg amcseg;
Res res;
AVERT(Seg, seg);
amcseg = Seg2amcSeg(seg);
/* no useful checks for base and size */
AVERT(Bool, reservoirPermit);
/* Initialize the superclass fields first via next-method call */
super = SEG_SUPERCLASS(amcSegClass);
res = super->init(seg, pool, base, size, reservoirPermit, args);
if(res != ResOK)
return res;
amcseg->segTypeP = segtype; /* .segtype */
amcseg->new = TRUE;
amcseg->sig = amcSegSig;
AVERT(amcSeg, amcseg);
return ResOK;
}
/* AMCSegSketch -- summarise the segment state for a human reader
*
* Write a short human-readable text representation of the segment
* state into storage indicated by pbSketch+cbSketch.
*
* A typical sketch is "bGW_", meaning the seg has a nailboard, has
* some Grey and some White objects, and has no buffer attached.
*/
static void AMCSegSketch(Seg seg, char *pbSketch, size_t cbSketch)
{
amcSeg amcseg;
Buffer buffer;
AVER(pbSketch);
AVER(cbSketch >= 5);
AVERT(Seg, seg);
amcseg = Seg2amcSeg(seg);
AVERT(amcSeg, amcseg);
if(SegNailed(seg) == TraceSetEMPTY) {
pbSketch[0] = 'm'; /* mobile */
} else if (amcSegHasNailboard(seg)) {
pbSketch[0] = 'b'; /* boarded */
} else {
pbSketch[0] = 's'; /* stuck */
}
if(SegGrey(seg) == TraceSetEMPTY) {
pbSketch[1] = '_';
} else {
pbSketch[1] = 'G'; /* Grey */
}
if(SegWhite(seg) == TraceSetEMPTY) {
pbSketch[2] = '_';
} else {
pbSketch[2] = 'W'; /* White */
}
buffer = SegBuffer(seg);
if(buffer == NULL) {
pbSketch[3] = '_';
} else {
Bool mut = BufferIsMutator(buffer);
Bool flipped = ((buffer->mode & BufferModeFLIPPED) != 0);
Bool trapped = BufferIsTrapped(buffer);
Bool limitzeroed = (buffer->apStruct.limit == 0);
pbSketch[3] = 'X'; /* I don't know what's going on! */
if((flipped == trapped) && (trapped == limitzeroed)) {
if(mut) {
if(flipped) {
pbSketch[3] = 's'; /* stalo */
} else {
pbSketch[3] = 'n'; /* neo */
}
} else {
if(!flipped) {
pbSketch[3] = 'f'; /* forwarding */
}
}
} else {
/* I don't know what's going on! */
}
}
pbSketch[4] = '\0';
AVER(4 < cbSketch);
}
/* AMCSegDescribe -- describe the contents of a segment
*
* See <design/poolamc/#seg-describe>.
*/
static Res AMCSegDescribe(Seg seg, mps_lib_FILE *stream)
{
Res res;
Pool pool;
amcSeg amcseg;
SegClass super;
Addr i, p, base, limit, init;
Align step;
Size row;
char abzSketch[5];
if(!CHECKT(Seg, seg))
return ResFAIL;
if(stream == NULL)
return ResFAIL;
amcseg = Seg2amcSeg(seg);
if(!CHECKT(amcSeg, amcseg))
return ResFAIL;
/* Describe the superclass fields first via next-method call */
super = SEG_SUPERCLASS(amcSegClass);
res = super->describe(seg, stream);
if(res != ResOK)
return res;
pool = SegPool(seg);
step = PoolAlignment(pool);
row = step * 64;
base = SegBase(seg);
p = AddrAdd(base, pool->format->headerSize);
limit = SegLimit(seg);
res = WriteF(stream,
"AMC seg $P [$A,$A){\n",
(WriteFP)seg, (WriteFA)base, (WriteFA)limit,
NULL);
if(res != ResOK)
return res;
if(amcSegHasNailboard(seg)) {
res = WriteF(stream, " Boarded\n", NULL);
/* @@@@ should have AMCNailboardDescribe() */
} else {
if(SegNailed(seg) == TraceSetEMPTY) {
res = WriteF(stream, " Mobile\n", NULL);
} else {
res = WriteF(stream, " Stuck\n", NULL);
}
}
if(res != ResOK)
return res;
res = WriteF(stream, " Map: *===:object bbbb:buffer\n", NULL);
if(res != ResOK)
return res;
if(SegBuffer(seg) != NULL)
init = BufferGetInit(SegBuffer(seg));
else
init = limit;
for(i = base; i < limit; i = AddrAdd(i, row)) {
Addr j;
char c;
res = WriteF(stream, " $A ", i, NULL);
if(res != ResOK)
return res;
/* @@@@ This needs to describe nailboards as well */
/* @@@@ This misses a header-sized pad at the end. */
for(j = i; j < AddrAdd(i, row); j = AddrAdd(j, step)) {
if(j >= limit)
c = ' '; /* if seg is not a whole number of print rows */
else if(j >= init)
c = 'b';
else if(j == p) {
c = '*';
p = (pool->format->skip)(p);
} else {
c = '=';
}
res = WriteF(stream, "$C", c, NULL);
if(res != ResOK)
return res;
}
res = WriteF(stream, "\n", NULL);
if(res != ResOK)
return res;
}
AMCSegSketch(seg, abzSketch, NELEMS(abzSketch));
res = WriteF(stream, " Sketch: $S\n", (WriteFS)abzSketch, NULL);
if(res != ResOK)
return res;
res = WriteF(stream, "} AMC Seg $P\n", (WriteFP)seg, NULL);
if(res != ResOK)
return res;
return ResOK;
}
/* amcSegClass -- Class definition for AMC segments */
DEFINE_SEG_CLASS(amcSegClass, class)
{
INHERIT_CLASS(class, GCSegClass);
SegClassMixInNoSplitMerge(class); /* no support for this (yet) */
class->name = "AMCSEG";
class->size = sizeof(amcSegStruct);
class->init = AMCSegInit;
class->describe = AMCSegDescribe;
}
/* amcSegHasNailboard -- test whether the segment has a nailboard
*
* See <design/poolamc/#fix.nail.distinguish>.
*/
static Bool amcSegHasNailboard(Seg seg)
{
int type;
type = *amcSegTypeP(seg);
AVER(type == AMCPTypeNailboard || type == AMCPTypeGen);
return type == AMCPTypeNailboard;
}
/* amcSegNailboard -- get the nailboard for this segment */
static amcNailboard amcSegNailboard(Seg seg)
{
int *p;
p = amcSegTypeP(seg);
AVER(amcSegHasNailboard(seg));
return PARENT(amcNailboardStruct, type, p);
}
/* amcSegGen -- get the generation structure for this segment */
static amcGen amcSegGen(Seg seg)
{
if(amcSegHasNailboard(seg)) {
amcNailboard Nailboard = amcSegNailboard(seg);
return Nailboard->gen;
} else {
int *p;
p = amcSegTypeP(seg);
return PARENT(amcGenStruct, type, p);
}
}
/* AMCStruct -- pool AMC descriptor
*
* See <design/poolamc/#struct>.
*/
#define AMCSig ((Sig)0x519A3C99) /* SIGnature AMC */
typedef struct PageRetStruct {
Count pCond; /* pages Condemned */
Count pRet; /* pages Retained (in place) */
/* Small */
Count pCS; /* pages Condemned in Small segments */
Count pRS; /* pages Retained in Small segments */
/* Medium */
Count sCM; /* segments Condemned: Medium */
/* ...= upper bound of how many extra pages it */
/* would have cost, had we chosen to LSP-pad */
/* all these segments. */
Count pCM; /* pages Condemned in Medium segments */
Count sRM; /* segments Retained: Medium */
Count pRM; /* pages Retained in Medium segments: */
Count pRM1; /* ...because obj 1 was preserved in place */
/* ...because a rest obj was pip, causing: */
Count pRMrr; /* ...retained rest pages (page where rest obj is) */
Count pRMr1; /* ...retained obj 1 pages (purely NMR pad) */
/* Large */
Count sCL; /* segments Condemned: Large */
/* ...= upper bound of how many extra pages it */
/* has cost to LSP-pad all these segments. */
Count pCL; /* pages Condemned in Large segments */
Count sRL; /* segments Retained: Large */
Count pRL; /* pages Retained in Large segments */
Count pRLr; /* ...because a rest obj (actually LSP) was pip */
/* The interesting things about this report are:
* - How many pages are actually being retained? (pRet)
* - Percentage? (pRet/pCond)
* - Is the major contribution from Small, Medium, or Large segs?
*
* Generally, pages retained because obj 1 needed to be preserved in
* place are ok (because no alternative placement could have retained
* fewer pages), but pages retained by a rest obj are unfortunate
* (better placement, putting the small rest objs in their own seg,
* would have retained fewer pages). In particular:
*
* The LSP threshold is a payoff between the wasted space from
* LSP-padding, versus the risk of increased page-retention (due to
* rest objs) from not LSP-padding.
*
* For Medium segs, where we do not do LSP-padding:
* - LSP would have required at most sCM extra pages;
* - the extra retention incurred by not LSP-padding is pRMr1.
* A high pRMr1 => lots of Medium segs getting retained by the rest
* objs tacked on after obj 1. Consider lowering LSP-threshold.
*
* For Large segs we do LSP padding. This has a cost; upper bound is
* sCL extra pages. But the benefit should be greatly reduced ambig
* refs to rest objs. With LSP, the only rest obj is the LSP pad
* itself. We expect that ambig refs to this are rare, so currently
* we do not implement .large.lsp-no-retain. But we do record the
* occurrence of pages retained by a ref to an LSP pad: pPLr. A high
* pRLr => perhaps .large.lsp-no-retain should be implemented?
*
* If the mutator is causing a lot of page retention, then sRM/pRM
* and sRL/pRL should give some picture of the number of retained
* objects and their average size.
*/
} PageRetStruct;
/* static => init'd to zero */
static struct PageRetStruct pageretstruct_Zero;
typedef struct AMCStruct { /* <design/poolamc/#struct> */
PoolStruct poolStruct; /* generic pool structure */
RankSet rankSet; /* rankSet for entire pool */
RingStruct genRing; /* ring of generations */
Bool gensBooted; /* used during boot (init) */
Chain chain; /* chain used by this pool */
size_t gens; /* number of generations */
amcGen *gen; /* (pointer to) array of generations */
amcGen nursery; /* the default mutator generation */
amcGen rampGen; /* the ramp generation */
amcGen afterRampGen; /* the generation after rampGen */
unsigned rampCount; /* <design/poolamc/#ramp.count> */
int rampMode; /* <design/poolamc/#ramp.mode> */
/* page retention in an in-progress trace */
STATISTIC_DECL(PageRetStruct pageretstruct[TraceLIMIT]);
Sig sig; /* <design/pool/#outer-structure.sig> */
} AMCStruct;
#define Pool2AMC(pool) PARENT(AMCStruct, poolStruct, (pool))
#define AMC2Pool(amc) (&(amc)->poolStruct)
/* amcGenCheck -- check consistency of a generation structure */
static Bool amcGenCheck(amcGen gen)
{
Arena arena;
AMC amc;
CHECKS(amcGen, gen);
CHECKD(PoolGen, &gen->pgen);
amc = amcGenAMC(gen);
CHECKU(AMC, amc);
CHECKL(gen->type == AMCPTypeGen);
CHECKD(Buffer, gen->forward);
CHECKL(RingCheck(&gen->amcRing));
CHECKL((gen->pgen.totalSize == 0) == (gen->segs == 0));
arena = amc->poolStruct.arena;
CHECKL(gen->pgen.totalSize >= gen->segs * ArenaAlign(arena));
return TRUE;
}
/* amcNailboardCheck -- check the nailboard */
static Bool amcNailboardCheck(amcNailboard board)
{
CHECKS(amcNailboard, board);
CHECKL(board->type == AMCPTypeNailboard);
CHECKD(amcGen, board->gen);
/* nails is >= number of set bits in mark, but we can't check this */
/* We know that shift corresponds to pool->align. */
CHECKL(BoolCheck(board->newMarks));
CHECKL(board->distinctNails <= board->nails);
CHECKL(1uL << board->markShift
== PoolAlignment(amcGenPool(board->gen)));
/* weak check for BTs @@@@ */
CHECKL(board->mark != NULL);
return TRUE;
}
/* amcBufStruct -- AMC Buffer subclass
*
* This subclass of SegBuf records a link to a generation.
*/
#define amcBufSig ((Sig)0x519A3CBF) /* SIGnature AMC BuFfer */
typedef struct amcBufStruct *amcBuf;
typedef struct amcBufStruct {
SegBufStruct segbufStruct; /* superclass fields must come first */
amcGen gen; /* The AMC generation */
Sig sig; /* <design/sig/> */
} amcBufStruct;
/* Buffer2amcBuf -- convert generic Buffer to an amcBuf */
#define Buffer2amcBuf(buffer) ((amcBuf)(buffer))
/* amcBufCheck -- check consistency of an amcBuf */
static Bool amcBufCheck(amcBuf amcbuf)
{
SegBuf segbuf;
CHECKS(amcBuf, amcbuf);
segbuf = &amcbuf->segbufStruct;
CHECKL(SegBufCheck(segbuf));
if(amcbuf->gen != NULL)
CHECKD(amcGen, amcbuf->gen);
return TRUE;
}
/* amcBufGen -- Return the AMC generation of an amcBuf */
static amcGen amcBufGen(Buffer buffer)
{
return Buffer2amcBuf(buffer)->gen;
}
/* amcBufSetGen -- Set the AMC generation of an amcBuf */
static void amcBufSetGen(Buffer buffer, amcGen gen)
{
amcBuf amcbuf;
if(gen != NULL)
AVERT(amcGen, gen);
amcbuf = Buffer2amcBuf(buffer);
amcbuf->gen = gen;
}
/* AMCBufInit -- Initialize an amcBuf */
static Res AMCBufInit(Buffer buffer, Pool pool, va_list args)
{
AMC amc;
amcBuf amcbuf;
BufferClass superclass;
Res res;
AVERT(Buffer, buffer);
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
/* call next method */
superclass = BUFFER_SUPERCLASS(amcBufClass);
res = (*superclass->init)(buffer, pool, args);
if(res != ResOK)
return res;
amcbuf = Buffer2amcBuf(buffer);
if(BufferIsMutator(buffer)) {
/* Set up the buffer to be allocating in the nursery. */
amcbuf->gen = amc->nursery;
} else {
/* No gen yet -- see <design/poolamc/#gen.forward>. */
amcbuf->gen = NULL;
}
amcbuf->sig = amcBufSig;
AVERT(amcBuf, amcbuf);
BufferSetRankSet(buffer, amc->rankSet);
return ResOK;
}
/* AMCBufFinish -- Finish an amcBuf */
static void AMCBufFinish(Buffer buffer)
{
BufferClass super;
amcBuf amcbuf;
AVERT(Buffer, buffer);
amcbuf = Buffer2amcBuf(buffer);
AVERT(amcBuf, amcbuf);
amcbuf->sig = SigInvalid;
/* Finish the superclass fields last. */
super = BUFFER_SUPERCLASS(amcBufClass);
super->finish(buffer);
}
/* amcBufClass -- The class definition */
DEFINE_BUFFER_CLASS(amcBufClass, class)
{
INHERIT_CLASS(class, SegBufClass);
class->name = "AMCBUF";
class->size = sizeof(amcBufStruct);
class->init = AMCBufInit;
class->finish = AMCBufFinish;
}
/* amcGenCreate -- create a generation */
static Res amcGenCreate(amcGen *genReturn, AMC amc, Serial genNr)
{
Arena arena;
Buffer buffer;
Pool pool;
amcGen gen;
Res res;
void *p;
pool = AMC2Pool(amc);
arena = pool->arena;
res = ControlAlloc(&p, arena, sizeof(amcGenStruct), FALSE);
if(res != ResOK)
goto failControlAlloc;
gen = (amcGen)p;
res = BufferCreate(&buffer, EnsureamcBufClass(), pool, FALSE);
if(res != ResOK)
goto failBufferCreate;
res = PoolGenInit(&gen->pgen, amc->chain, genNr, pool);
if(res != ResOK)
goto failGenInit;
gen->type = AMCPTypeGen;
RingInit(&gen->amcRing);
gen->segs = 0;
gen->forward = buffer;
gen->sig = amcGenSig;
AVERT(amcGen, gen);
RingAppend(&amc->genRing, &gen->amcRing);
EVENT_PP(AMCGenCreate, amc, gen);
*genReturn = gen;
return ResOK;
failGenInit:
BufferDestroy(buffer);
failBufferCreate:
ControlFree(arena, p, sizeof(amcGenStruct));
failControlAlloc:
return res;
}
/* amcGenDestroy -- destroy a generation */
static void amcGenDestroy(amcGen gen)
{
Arena arena;
AVERT(amcGen, gen);
AVER(gen->segs == 0);
AVER(gen->pgen.totalSize == 0);
EVENT_P(AMCGenDestroy, gen);
arena = PoolArena(amcGenPool(gen));
gen->sig = SigInvalid;
RingRemove(&gen->amcRing);
RingFinish(&gen->amcRing);
PoolGenFinish(&gen->pgen);
BufferDestroy(gen->forward);
ControlFree(arena, gen, sizeof(amcGenStruct));
}
/* amcGenDescribe -- describe an AMC generation */
static Res amcGenDescribe(amcGen gen, mps_lib_FILE *stream)
{
Res res;
if(!CHECKT(amcGen, gen))
return ResFAIL;
res = WriteF(stream,
" amcGen $P ($U) {\n",
(WriteFP)gen, (WriteFU)amcGenNr(gen),
" buffer $P\n", gen->forward,
" segs $U, totalSize $U, newSize $U\n",
(WriteFU)gen->segs,
(WriteFU)gen->pgen.totalSize,
(WriteFU)gen->pgen.newSize,
" } amcGen\n", NULL);
return res;
}
/* amcSegCreateNailboard -- create nailboard for segment */
static Res amcSegCreateNailboard(Seg seg, Pool pool)
{
amcNailboard board;
Arena arena;
Count bits;
Res res;
void *p;
AVER(!amcSegHasNailboard(seg));
arena = PoolArena(pool);
res = ControlAlloc(&p, arena, sizeof(amcNailboardStruct), FALSE);
if(res != ResOK)
goto failAllocNailboard;
board = p;
board->type = AMCPTypeNailboard;
board->gen = amcSegGen(seg);
board->nails = (Count)0;
board->distinctNails = (Count)0;
board->newMarks = FALSE;
board->markShift = SizeLog2((Size)pool->alignment);
/* [I wonder what this comment is referring to? 2007-07-11 DRJ] */
/* See d.m.p.Nailboard.size. */
bits = (SegSize(seg) + pool->format->headerSize) >> board->markShift;
res = ControlAlloc(&p, arena, BTSize(bits), FALSE);
if(res != ResOK)
goto failMarkTable;
board->mark = p;
BTResRange(board->mark, 0, bits);
board->sig = amcNailboardSig;
AVERT(amcNailboard, board);
amcSegSetTypeP(seg, &board->type); /* .segtype */
return ResOK;
failMarkTable:
ControlFree(arena, board, sizeof(amcNailboardStruct));
failAllocNailboard:
return res;
}
/* amcSegDestroyNailboard -- destroy the nailboard of a segment */
static void amcSegDestroyNailboard(Seg seg, Pool pool)
{
amcNailboard board;
amcGen gen;
Arena arena;
Count bits;
gen = amcSegGen(seg);
board = amcSegNailboard(seg);
AVERT(amcNailboard, board);
arena = PoolArena(pool);
/* See d.m.p.Nailboard.size. */
bits = (SegSize(seg) + pool->format->headerSize) >> board->markShift;
ControlFree(arena, board->mark, BTSize(bits));
board->sig = SigInvalid;
ControlFree(arena, board, sizeof(amcNailboardStruct));
amcSegSetTypeP(seg, &gen->type); /* .segtype */
}
/* amcNailGetMark -- get the mark bit for ref from the nailboard */
static Bool amcNailGetMark(Seg seg, Ref ref)
{
amcNailboard board;
Index i;
board = amcSegNailboard(seg);
AVERT(amcNailboard, board);
i = AddrOffset(SegBase(seg), ref) >> board->markShift;
return BTGet(board->mark, i);
}
/* amcNailGetAndSetMark -- set the mark bit for ref in the nailboard
*
* Returns the old value.
*/
static Bool amcNailGetAndSetMark(Seg seg, Ref ref)
{
amcNailboard board;
Index i;
board = amcSegNailboard(seg);
AVERT(amcNailboard, board);
++board->nails;
i = AddrOffset(SegBase(seg), ref) >> board->markShift;
if(!BTGet(board->mark, i)) {
BTSet(board->mark, i);
board->newMarks = TRUE;
++board->distinctNails;
return FALSE;
}
return TRUE;
}
/* amcNailMarkRange -- nail a range in the board
*
* We nail the objects laying between base and limit, i.e., mark the
* bits that correspond to client pointers for them. We may assume
* that the range is unmarked.
*/
static void amcNailMarkRange(Seg seg, Addr base, Addr limit)
{
amcNailboard board;
Index ibase, ilimit;
Size headerSize;
AVER(SegBase(seg) <= base);
AVER(base < SegLimit(seg));
AVER(SegBase(seg) <= limit);
AVER(limit <= SegLimit(seg));
AVER(base < limit);
board = amcSegNailboard(seg);
AVERT(amcNailboard, board);
headerSize = SegPool(seg)->format->headerSize;
ibase = (AddrOffset(SegBase(seg), base) + headerSize)
>> board->markShift;
ilimit = (AddrOffset(SegBase(seg), limit) + headerSize)
>> board->markShift;
AVER(BTIsResRange(board->mark, ibase, ilimit));
BTSetRange(board->mark, ibase, ilimit);
board->nails += ilimit - ibase;
board->distinctNails += ilimit - ibase;
}
/* amcNailRangeIsMarked -- check that a range in the board is marked
*
* Like amcNailMarkRange, we take the arguments as referring to base
* pointers and look at the bits of the corresponding client pointers.
*/
static Bool amcNailRangeIsMarked(Seg seg, Addr base, Addr limit)
{
amcNailboard board;
Index ibase, ilimit;
Size headerSize;
AVER(SegBase(seg) <= base);
AVER(base < SegLimit(seg));
AVER(SegBase(seg) <= limit);
AVER(limit <= SegLimit(seg));
AVER(base < limit);
board = amcSegNailboard(seg);
AVERT(amcNailboard, board);
headerSize = SegPool(seg)->format->headerSize;
ibase = (AddrOffset(SegBase(seg), base) + headerSize)
>> board->markShift;
ilimit = (AddrOffset(SegBase(seg), limit) + headerSize)
>> board->markShift;
return BTIsSetRange(board->mark, ibase, ilimit);
}
/* amcInitComm -- initialize AMC/Z pool
*
* See <design/poolamc/#init>.
* Shared by AMCInit and AMCZinit.
*/
static Res amcInitComm(Pool pool, RankSet rankSet, va_list arg)
{
AMC amc;
Res res;
Arena arena;
TraceId ti;
Trace trace;
Index i;
size_t genArraySize;
size_t genCount;
AVER(pool != NULL);
amc = Pool2AMC(pool);
arena = PoolArena(pool);
pool->format = va_arg(arg, Format);
AVERT(Format, pool->format);
pool->alignment = pool->format->alignment;
amc->chain = va_arg(arg, Chain);
AVERT(Chain, amc->chain);
amc->rankSet = rankSet;
RingInit(&amc->genRing);
/* amc gets checked before the generations get created, but they */
/* do get created later in this function. */
amc->gen = NULL;
amc->nursery = NULL;
amc->rampGen = NULL;
amc->afterRampGen = NULL;
amc->gensBooted = FALSE;
amc->rampCount = 0;
amc->rampMode = RampOUTSIDE;
TRACE_SET_ITER(ti, trace, TraceSetUNIV, arena)
STATISTIC(amc->pageretstruct[ti] = pageretstruct_Zero);
TRACE_SET_ITER_END(ti, trace, TraceSetUNIV, arena);
if(pool->format->headerSize == 0) {
pool->fix = AMCFix;
} else {
pool->fix = AMCHeaderFix;
}
amc->sig = AMCSig;
AVERT(AMC, amc);
/* Init generations. */
genCount = ChainGens(amc->chain);
{
void *p;
/* One gen for each one in the chain plus dynamic gen. */
genArraySize = sizeof(amcGen) * (genCount + 1);
res = ControlAlloc(&p, arena, genArraySize, FALSE);
if(res != ResOK)
goto failGensAlloc;
amc->gen = p;
for(i = 0; i < genCount + 1; ++i) {
res = amcGenCreate(&amc->gen[i], amc, (Serial)i);
if(res != ResOK) {
goto failGenAlloc;
}
}
/* Set up forwarding buffers. */
for(i = 0; i < genCount; ++i) {
amcBufSetGen(amc->gen[i]->forward, amc->gen[i+1]);
}
/* Dynamic gen forwards to itself. */
amcBufSetGen(amc->gen[genCount]->forward, amc->gen[genCount]);
}
amc->nursery = amc->gen[0];
amc->rampGen = amc->gen[genCount-1]; /* last ephemeral gen */
amc->afterRampGen = amc->gen[genCount];
amc->gensBooted = TRUE;
AVERT(AMC, amc);
EVENT_PP(AMCInit, pool, amc);
if(rankSet == RankSetEMPTY)
EVENT_PP(PoolInitAMCZ, pool, pool->format);
else
EVENT_PP(PoolInitAMC, pool, pool->format);
return ResOK;
failGenAlloc:
while(i > 0) {
--i;
amcGenDestroy(amc->gen[i]);
}
ControlFree(arena, amc->gen, genArraySize);
failGensAlloc:
return res;
}
static Res AMCInit(Pool pool, va_list arg)
{
return amcInitComm(pool, RankSetSingle(RankEXACT), arg);
}
static Res AMCZInit(Pool pool, va_list arg)
{
return amcInitComm(pool, RankSetEMPTY, arg);
}
/* AMCFinish -- finish AMC pool
*
* See <design/poolamc/#finish>.
*/
static void AMCFinish(Pool pool)
{
AMC amc;
Ring ring;
Ring node, nextNode;
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
EVENT_P(AMCFinish, amc);
/* @@@@ Make sure that segments aren't buffered by forwarding */
/* buffers. This is a hack which allows the pool to be destroyed */
/* while it is collecting. Note that there aren't any mutator */
/* buffers by this time. */
RING_FOR(node, &amc->genRing, nextNode) {
amcGen gen = RING_ELT(amcGen, amcRing, node);
BufferDetach(gen->forward, pool);
/* Maintain invariant < totalSize. */
gen->pgen.newSize = (Size)0;
}
ring = PoolSegRing(pool);
RING_FOR(node, ring, nextNode) {
Seg seg = SegOfPoolRing(node);
Size size;
amcGen gen = amcSegGen(seg);
--gen->segs;
size = SegSize(seg);
gen->pgen.totalSize -= size;
SegFree(seg);
}
/* Disassociate forwarding buffers from gens before they are */
/* destroyed. */
ring = &amc->genRing;
RING_FOR(node, ring, nextNode) {
amcGen gen = RING_ELT(amcGen, amcRing, node);
amcBufSetGen(gen->forward, NULL);
}
RING_FOR(node, ring, nextNode) {
amcGen gen = RING_ELT(amcGen, amcRing, node);
amcGenDestroy(gen);
}
amc->sig = SigInvalid;
}
/* AMCBufferFill -- refill an allocation buffer
*
* See <design/poolamc/#fill>.
*/
static Res AMCBufferFill(Addr *baseReturn, Addr *limitReturn,
Pool pool, Buffer buffer, Size size,
Bool withReservoirPermit)
{
Seg seg;
AMC amc;
Res res;
Addr base, limit;
Arena arena;
Size alignedSize;
amcGen gen;
Serial genNr;
SegPrefStruct segPrefStruct;
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
AVER(baseReturn != NULL);
AVER(limitReturn != NULL);
AVERT(Buffer, buffer);
AVER(BufferIsReset(buffer));
AVER(size > 0);
AVER(SizeIsAligned(size, PoolAlignment(pool)));
AVERT(Bool, withReservoirPermit);
gen = amcBufGen(buffer);
AVERT(amcGen, gen);
/* Create and attach segment. The location of this segment is */
/* expressed as a generation number. We rely on the arena to */
/* organize locations appropriately. */
arena = PoolArena(pool);
alignedSize = SizeAlignUp(size, ArenaAlign(arena));
segPrefStruct = *SegPrefDefault();
SegPrefExpress(&segPrefStruct, SegPrefCollected, NULL);
genNr = PoolGenNr(&gen->pgen);
SegPrefExpress(&segPrefStruct, SegPrefGen, &genNr);
res = SegAlloc(&seg, amcSegClassGet(), &segPrefStruct,
alignedSize, pool, withReservoirPermit,
&gen->type); /* .segtype */
if(res != ResOK)
return res;
AVER(alignedSize == SegSize(seg));
/* <design/seg/#field.rankSet.start> */
if(BufferRankSet(buffer) == RankSetEMPTY)
SegSetRankAndSummary(seg, BufferRankSet(buffer), RefSetEMPTY);
else
SegSetRankAndSummary(seg, BufferRankSet(buffer), RefSetUNIV);
/* Put the segment in the generation indicated by the buffer. */
++gen->segs;
gen->pgen.totalSize += alignedSize;
/* If ramping, don't count survivors in newSize. */
if(amc->rampMode != RampRAMPING
|| buffer != amc->rampGen->forward
|| gen != amc->rampGen)
{
gen->pgen.newSize += alignedSize;
} else {
Seg2amcSeg(seg)->new = FALSE;
}
PoolGenUpdateZones(&gen->pgen, seg);
base = SegBase(seg);
*baseReturn = base;
if(alignedSize < AMCLargeSegPAGES * ArenaAlign(arena)) {
/* Small or Medium segment: give the buffer the entire seg. */
limit = AddrAdd(base, alignedSize);
AVER(limit == SegLimit(seg));
} else {
/* Large segment: ONLY give the buffer the size requested, and */
/* pad the remainder of the segment: see job001811. */
Size padSize;
limit = AddrAdd(base, size);
AVER(limit <= SegLimit(seg));
padSize = alignedSize - size;
AVER(SizeIsAligned(padSize, PoolAlignment(pool)));
AVER(AddrAdd(limit, padSize) == SegLimit(seg));
if(padSize > 0) {
ShieldExpose(arena, seg);
(*pool->format->pad)(limit, padSize);
ShieldCover(arena, seg);
}
}
*limitReturn = limit;
return ResOK;
}
/* amcBufferEmpty -- detach a buffer from a segment
*
* See <design/poolamc/#flush>.
*/
static void AMCBufferEmpty(Pool pool, Buffer buffer,
Addr init, Addr limit)
{
AMC amc;
Size size;
Arena arena;
Seg seg;
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
AVERT(Buffer, buffer);
AVER(BufferIsReady(buffer));
seg = BufferSeg(buffer);
AVERT(Seg, seg);
AVER(init <= limit);
arena = BufferArena(buffer);
if(SegSize(seg) < AMCLargeSegPAGES * ArenaAlign(arena)) {
/* Small or Medium segment: buffer had the entire seg. */
AVER(limit == SegLimit(seg));
} else {
/* Large segment: buffer had only the size requested; job001811. */
AVER(limit <= SegLimit(seg));
}
/* <design/poolamc/#flush.pad> */
size = AddrOffset(init, limit);
if(size > 0) {
ShieldExpose(arena, seg);
(*pool->format->pad)(init, size);
ShieldCover(arena, seg);
}
}
/* AMCRampBegin -- note an entry into a ramp pattern */
static void AMCRampBegin(Pool pool, Buffer buf, Bool collectAll)
{
AMC amc;
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
AVERT(Buffer, buf);
AVERT(Bool, collectAll);
UNUSED(collectAll); /* obsolete */
AVER(amc->rampCount < UINT_MAX);
++amc->rampCount;
if(amc->rampCount == 1) {
if(amc->rampMode != RampFINISH)
amc->rampMode = RampBEGIN;
}
}
/* AMCRampEnd -- note an exit from a ramp pattern */
static void AMCRampEnd(Pool pool, Buffer buf)
{
AMC amc;
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
AVERT(Buffer, buf);
AVER(amc->rampCount > 0);
--amc->rampCount;
if(amc->rampCount == 0) {
PoolGen pgen = &amc->rampGen->pgen;
Ring node, nextNode;
if(amc->rampMode == RampRAMPING) {
/* We were ramping, so clean up. */
amc->rampMode = RampFINISH;
} else {
amc->rampMode = RampOUTSIDE;
}
/* Adjust amc->rampGen->pgen.newSize: Now count all the segments */
/* in the ramp generation as new (except if they're white). */
RING_FOR(node, PoolSegRing(pool), nextNode) {
Seg seg = SegOfPoolRing(node);
if(amcSegGen(seg) == amc->rampGen && !Seg2amcSeg(seg)->new
&& SegWhite(seg) == TraceSetEMPTY)
{
pgen->newSize += SegSize(seg);
Seg2amcSeg(seg)->new = TRUE;
}
}
}
}
/* AMCWhiten -- condemn the segment for the trace
*
* If the segment has a mutator buffer on it, we nail the buffer,
* because we can't scan or reclaim uncommitted buffers.
*/
static Res AMCWhiten(Pool pool, Trace trace, Seg seg)
{
amcGen gen;
AMC amc;
Buffer buffer;
Res res;
AVERT(Pool, pool);
AVERT(Trace, trace);
AVERT(Seg, seg);
buffer = SegBuffer(seg);
if(buffer != NULL) {
AVERT(Buffer, buffer);
if(!BufferIsMutator(buffer)) { /* forwarding buffer */
AVER(BufferIsReady(buffer));
BufferDetach(buffer, pool);
} else { /* mutator buffer */
if(BufferScanLimit(buffer) == SegBase(seg)) {
/* There's nothing but the buffer, don't condemn. */
return ResOK;
}
/* [The following else-if section is just a comment added in */
/* 1998-10-08. It has never worked. RHSK 2007-01-16] */
/* else if (BufferScanLimit(buffer) == BufferLimit(buffer)) { */
/* The buffer is full, so it won't be used by the mutator. */
/* @@@@ We should detach it, but can't for technical */
/* reasons. */
/* BufferDetach(buffer, pool); */
/* } */
else {
/* There is an active buffer, make sure it's nailed. */
if(!amcSegHasNailboard(seg)) {
if(SegNailed(seg) == TraceSetEMPTY) {
res = amcSegCreateNailboard(seg, pool);
if(res != ResOK) {
/* Can't create nailboard, don't condemn. */
return ResOK;
}
if(BufferScanLimit(buffer) != BufferLimit(buffer)) {
amcNailMarkRange(seg, BufferScanLimit(buffer),
BufferLimit(buffer));
}
++trace->nailCount;
SegSetNailed(seg, TraceSetSingle(trace));
} else {
/* Segment is nailed already, cannot create a nailboard */
/* (see .nail.new), just give up condemning. */
return ResOK;
}
} else {
/* We have a nailboard, the buffer must be nailed already. */
AVER((BufferScanLimit(buffer) == BufferLimit(buffer))
|| amcNailRangeIsMarked(seg, BufferScanLimit(buffer),
BufferLimit(buffer)));
/* Nail it for this trace as well. */
SegSetNailed(seg, TraceSetAdd(SegNailed(seg), trace));
}
/* We didn't condemn the buffer, subtract it from the count. */
/* @@@@ We could subtract all the nailed grains. */
/* Relies on unsigned arithmetic wrapping round */
/* on under- and overflow (which it does). */
trace->condemned -= AddrOffset(BufferScanLimit(buffer),
BufferLimit(buffer));
}
}
}
SegSetWhite(seg, TraceSetAdd(SegWhite(seg), trace));
trace->condemned += SegSize(seg);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
STATISTIC_STAT( {
Count pages;
AVER(SizeIsAligned(SegSize(seg), ArenaAlign(pool->arena)));
pages = SegSize(seg) / ArenaAlign(pool->arena);
AVER(pages != 0);
amc->pageretstruct[trace->ti].pCond += pages;
if(pages == 1) {
amc->pageretstruct[trace->ti].pCS += pages;
} else if(pages < AMCLargeSegPAGES) {
amc->pageretstruct[trace->ti].sCM += 1;
amc->pageretstruct[trace->ti].pCM += pages;
} else {
amc->pageretstruct[trace->ti].sCL += 1;
amc->pageretstruct[trace->ti].pCL += pages;
}
} );
gen = amcSegGen(seg);
AVERT(amcGen, gen);
if(Seg2amcSeg(seg)->new) {
gen->pgen.newSize -= SegSize(seg);
Seg2amcSeg(seg)->new = FALSE;
}
/* Ensure we are forwarding into the right generation. */
/* see <design/poolamc/#gen.ramp> */
/* This switching needs to be more complex for multiple traces. */
AVER(TraceSetIsSingle(PoolArena(pool)->busyTraces));
if(amc->rampMode == RampBEGIN && gen == amc->rampGen) {
BufferDetach(gen->forward, pool);
amcBufSetGen(gen->forward, gen);
amc->rampMode = RampRAMPING;
} else if(amc->rampMode == RampFINISH && gen == amc->rampGen) {
BufferDetach(gen->forward, pool);
amcBufSetGen(gen->forward, amc->afterRampGen);
amc->rampMode = RampCOLLECTING;
}
return ResOK;
}
/* amcScanNailedOnce -- make one scanning pass over a nailed segment
*
* *totalReturn set to TRUE iff all objects in segment scanned.
* *moreReturn set to FALSE only if there are no more objects
* on the segment that need scanning (which is normally the case).
* It is set to TRUE if scanning had to be abandoned early on, and
* also if during emergency fixing any new marks got added to the
* nailboard.
*/
static Res amcScanNailedOnce(Bool *totalReturn, Bool *moreReturn,
ScanState ss, Pool pool, Seg seg, AMC amc)
{
Addr p, limit;
Format format;
Res res;
Bool total = TRUE;
Size bytesScanned = 0;
UNUSED(amc); /* Actually only unused when telemetry is off. @@@@ */
EVENT_PPP(AMCScanBegin, amc, seg, ss); /* @@@@ use own event */
format = pool->format;
amcSegNailboard(seg)->newMarks = FALSE;
p = AddrAdd(SegBase(seg), format->headerSize);
while(SegBuffer(seg) != NULL) {
limit = AddrAdd(BufferScanLimit(SegBuffer(seg)),
format->headerSize);
if(p >= limit) {
AVER(p == limit);
goto returnGood;
}
while(p < limit) {
Addr q;
q = (*format->skip)(p);
if(amcNailGetMark(seg, p)) {
res = (*format->scan)(ss, p, q);
if(res != ResOK) {
*totalReturn = FALSE;
*moreReturn = TRUE;
return res;
}
bytesScanned += AddrOffset(p, q);
} else {
total = FALSE;
}
p = q;
}
AVER(p == limit);
}
/* Should have a ScanMarkedRange or something like that @@@@ */
/* to abstract common code. */
limit = AddrAdd(SegLimit(seg), format->headerSize);
/* @@@@ Shouldn't p be set to BufferLimit here?! */
while(p < limit) {
Addr q;
q = (*format->skip)(p);
if(amcNailGetMark(seg, p)) {
res = (*format->scan)(ss, p, q);
if(res != ResOK) {
*totalReturn = FALSE;
*moreReturn = TRUE;
return res;
}
bytesScanned += AddrOffset(p, q);
} else {
total = FALSE;
}
p = q;
}
AVER(p == limit);
returnGood:
EVENT_PPP(AMCScanEnd, amc, seg, ss); /* @@@@ use own event */
AVER(bytesScanned <= SegSize(seg));
ss->scannedSize += bytesScanned;
*totalReturn = total;
*moreReturn = amcSegNailboard(seg)->newMarks;
return ResOK;
}
/* amcScanNailed -- scan a nailed segment */
static Res amcScanNailed(Bool *totalReturn, ScanState ss, Pool pool,
Seg seg, AMC amc)
{
Bool total, moreScanning;
size_t loops = 0;
do {
Res res;
res = amcScanNailedOnce(&total, &moreScanning, ss, pool, seg, amc);
if(res != ResOK) {
*totalReturn = FALSE;
return res;
}
loops += 1;
} while(moreScanning);
if(loops > 1) {
{
/* Looped: should only happen under emergency tracing. */
TraceId ti;
Trace trace;
Bool emerg = FALSE;
TraceSet ts = ss->traces;
Arena arena = pool->arena;
TRACE_SET_ITER(ti, trace, ts, arena)
if(trace->emergency) {
emerg = TRUE;
}
TRACE_SET_ITER_END(ti, trace, ts, arena);
AVER(emerg);
}
{
/* Looped: fixed refs (from 1st pass) were seen by MPS_FIX1
* (in later passes), so the "ss.unfixedSummary" is _not_
* purely unfixed. In this one case, unfixedSummary is not
* accurate, and cannot be used to verify the SegSummary (see
* impl/trace/#verify.segsummary). Use ScanStateSetSummary to
* store ScanStateSummary in ss.fixedSummary and reset
* ss.unfixedSummary. See job001548.
*/
RefSet refset;
refset = ScanStateSummary(ss);
#if 1
/* A rare event, which might prompt a rare defect to appear. */
DIAG_SINGLEF(( "amcScanNailed_loop",
"scan completed, but had to loop $U times:\n", (WriteFU)loops,
" SegSummary: $B\n", (WriteFB)SegSummary(seg),
" ss.white: $B\n", (WriteFB)ss->white,
" ss.unfixedSummary: $B", (WriteFB)ss->unfixedSummary,
"$S\n", (WriteFS)(
(RefSetSub(ss->unfixedSummary, SegSummary(seg)))
? ""
: " <=== This would have failed .verify.segsummary!"
),
" ss.fixedSummary: $B\n", (WriteFB)ss->fixedSummary,
"ScanStateSummary: $B\n", (WriteFB)refset,
"MOVING ScanStateSummary TO fixedSummary, "
"RESETTING unfixedSummary.\n", NULL
));
#endif
ScanStateSetSummary(ss, refset);
}
}
*totalReturn = total;
return ResOK;
}
/* AMCScan -- scan a single seg, turning it black
*
* See <design/poolamc/#seg-scan>.
*/
static Res AMCScan(Bool *totalReturn, ScanState ss, Pool pool, Seg seg)
{
Addr base, limit;
Arena arena;
Format format;
AMC amc;
Res res;
AVER(totalReturn != NULL);
AVERT(ScanState, ss);
AVERT(Seg, seg);
AVERT(Pool, pool);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
format = pool->format;
arena = pool->arena;
if(amcSegHasNailboard(seg)) {
return amcScanNailed(totalReturn, ss, pool, seg, amc);
}
EVENT_PPP(AMCScanBegin, amc, seg, ss);
base = AddrAdd(SegBase(seg), format->headerSize);
/* <design/poolamc/#seg-scan.loop> */
while(SegBuffer(seg) != NULL) {
limit = AddrAdd(BufferScanLimit(SegBuffer(seg)),
format->headerSize);
if(base >= limit) {
/* @@@@ Are we sure we don't need scan the rest of the */
/* segment? */
AVER(base == limit);
*totalReturn = TRUE;
return ResOK;
}
res = (*format->scan)(ss, base, limit);
if(res != ResOK) {
*totalReturn = FALSE;
return res;
}
ss->scannedSize += AddrOffset(base, limit);
base = limit;
}
/* <design/poolamc/#seg-scan.finish> @@@@ base? */
limit = AddrAdd(SegLimit(seg), format->headerSize);
AVER(SegBase(seg) <= base);
AVER(base <= AddrAdd(SegLimit(seg), format->headerSize));
if(base < limit) {
res = (*format->scan)(ss, base, limit);
if(res != ResOK) {
*totalReturn = FALSE;
return res;
}
}
ss->scannedSize += AddrOffset(base, limit);
EVENT_PPP(AMCScanEnd, amc, seg, ss);
*totalReturn = TRUE;
return ResOK;
}
/* amcFixInPlace -- fix an reference without moving the object
*
* Usually this function is used for ambiguous references, but during
* emergency tracing may be used for references of any rank.
*
* If the segment has a nailboard then we use that to record the fix.
* Otherwise we simply grey and nail the entire segment.
*/
static void amcFixInPlace(Pool pool, Seg seg, ScanState ss, Ref *refIO)
{
Addr ref;
UNUSED(pool);
ref = (Addr)*refIO;
/* An ambiguous reference can point before the header. */
AVER(SegBase(seg) <= ref);
/* .ref-limit: A reference passed to Fix can't be beyond the */
/* segment, because then TraceFix would not have picked this */
/* segment. */
AVER(ref < SegLimit(seg));
EVENT_0(AMCFixInPlace);
if(amcSegHasNailboard(seg)) {
Bool wasMarked = amcNailGetAndSetMark(seg, ref);
/* If there are no new marks (i.e., no new traces for which we */
/* are marking, and no new mark bits set) then we can return */
/* immediately, without changing colour. */
if(TraceSetSub(ss->traces, SegNailed(seg)) && wasMarked)
return;
} else if(TraceSetSub(ss->traces, SegNailed(seg))) {
return;
}
SegSetNailed(seg, TraceSetUnion(SegNailed(seg), ss->traces));
if(SegRankSet(seg) != RankSetEMPTY)
SegSetGrey(seg, TraceSetUnion(SegGrey(seg), ss->traces));
}
/* AMCFixEmergency -- fix a reference, without allocating
*
* See <design/poolamc/#emergency.fix>.
*/
static Res AMCFixEmergency(Pool pool, ScanState ss, Seg seg,
Ref *refIO)
{
Arena arena;
AMC amc;
Addr newRef;
AVERT(Pool, pool);
AVERT(ScanState, ss);
AVERT(Seg, seg);
AVER(refIO != NULL);
arena = PoolArena(pool);
AVERT(Arena, arena);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
ss->wasMarked = TRUE;
if(ss->rank == RankAMBIG)
goto fixInPlace;
ShieldExpose(arena, seg);
newRef = (*pool->format->isMoved)(*refIO);
ShieldCover(arena, seg);
if(newRef != (Addr)0) {
/* Object has been forwarded already, so snap-out pointer. */
/* Useful weak pointer semantics not implemented. @@@@ */
*refIO = newRef;
return ResOK;
}
fixInPlace: /* see <design/poolamc/>.Nailboard.emergency */
amcFixInPlace(pool, seg, ss, refIO);
return ResOK;
}
/* AMCFix -- fix a reference to the pool
*
* See <design/poolamc/#fix>.
*/
Res AMCFix(Pool pool, ScanState ss, Seg seg, Ref *refIO)
{
Arena arena;
AMC amc;
Res res;
Format format; /* cache of pool->format */
Ref ref; /* reference to be fixed */
Ref newRef; /* new location, if moved */
Size length; /* length of object to be relocated */
Buffer buffer; /* buffer to allocate new copy into */
amcGen gen; /* generation of old copy of object */
TraceSet grey; /* greyness of object being relocated */
TraceSet toGrey; /* greyness of object's destination */
RefSet summary; /* summary of object being relocated */
RefSet toSummary; /* summary of object's destination */
Seg toSeg; /* segment to which object is being relocated */
/* <design/trace/#fix.noaver> */
AVERT_CRITICAL(Pool, pool);
AVERT_CRITICAL(ScanState, ss);
AVERT_CRITICAL(Seg, seg);
AVER_CRITICAL(refIO != NULL);
EVENT_0(AMCFix);
/* For the moment, assume that the object was already marked. */
/* (See <design/fix/#protocol.was-marked>.) */
ss->wasMarked = TRUE;
/* If the reference is ambiguous, set up the datastructures for */
/* managing a nailed segment. This involves marking the segment */
/* as nailed, and setting up a per-word mark table */
if(ss->rank == RankAMBIG) {
/* .nail.new: Check to see whether we need a Nailboard for */
/* this seg. We use "SegNailed(seg) == TraceSetEMPTY" */
/* rather than "!amcSegHasNailboard(seg)" because this avoids */
/* setting up a new nailboard when the segment was nailed, but */
/* had no nailboard. This must be avoided because otherwise */
/* assumptions in AMCFixEmergency will be wrong (essentially */
/* we will lose some pointer fixes because we introduced a */
/* nailboard). */
if(SegNailed(seg) == TraceSetEMPTY) {
res = amcSegCreateNailboard(seg, pool);
if(res != ResOK)
return res;
++ss->nailCount;
SegSetNailed(seg, TraceSetUnion(SegNailed(seg), ss->traces));
}
amcFixInPlace(pool, seg, ss, refIO);
return ResOK;
}
amc = Pool2AMC(pool);
AVERT_CRITICAL(AMC, amc);
format = pool->format;
ref = *refIO;
AVER_CRITICAL(SegBase(seg) <= ref);
AVER_CRITICAL(ref < SegLimit(seg));
arena = pool->arena;
/* .exposed.seg: Statements tagged ".exposed.seg" below require */
/* that "seg" (that is: the 'from' seg) has been ShieldExposed. */
ShieldExpose(arena, seg);
newRef = (*format->isMoved)(ref); /* .exposed.seg */
if(newRef == (Addr)0) {
/* If object is nailed already then we mustn't copy it: */
if(SegNailed(seg) != TraceSetEMPTY
&& (!amcSegHasNailboard(seg) || amcNailGetMark(seg, ref))) {
/* Segment only needs greying if there are new traces for */
/* which we are nailing. */
if(!TraceSetSub(ss->traces, SegNailed(seg))) {
if(SegRankSet(seg) != RankSetEMPTY) {
SegSetGrey(seg, TraceSetUnion(SegGrey(seg), ss->traces));
}
SegSetNailed(seg, TraceSetUnion(SegNailed(seg), ss->traces));
}
res = ResOK;
goto returnRes;
} else if(ss->rank == RankWEAK) {
/* Object is not preserved (neither moved, nor nailed) */
/* hence, reference should be splatted. */
goto updateReference;
}
/* Object is not preserved yet (neither moved, nor nailed) */
/* so should be preserved by forwarding. */
EVENT_A(AMCFixForward, newRef);
/* <design/fix/#protocol.was-marked> */
ss->wasMarked = FALSE;
/* Get the forwarding buffer from the object's generation. */
gen = amcSegGen(seg);
buffer = gen->forward;
AVER_CRITICAL(buffer != NULL);
length = AddrOffset(ref, (*format->skip)(ref)); /* .exposed.seg */
STATISTIC_STAT(++ss->forwardedCount);
ss->forwardedSize += length;
do {
res = BUFFER_RESERVE(&newRef, buffer, length, FALSE);
if(res != ResOK)
goto returnRes;
toSeg = BufferSeg(buffer);
ShieldExpose(arena, toSeg);
/* Since we're moving an object from one segment to another, */
/* union the greyness and the summaries together. */
grey = TraceSetUnion(ss->traces, SegGrey(seg));
toGrey = SegGrey(toSeg);
if(TraceSetDiff(grey, toGrey) != TraceSetEMPTY
&& SegRankSet(seg) != RankSetEMPTY) {
SegSetGrey(toSeg, TraceSetUnion(toGrey, grey));
}
summary = SegSummary(seg);
toSummary = SegSummary(toSeg);
if(RefSetDiff(summary, toSummary) != RefSetEMPTY) {
SegSetSummary(toSeg, RefSetUnion(toSummary, summary));
}
/* <design/trace/#fix.copy> */
(void)AddrCopy(newRef, ref, length); /* .exposed.seg */
ShieldCover(arena, toSeg);
} while(!BUFFER_COMMIT(buffer, newRef, length));
ss->copiedSize += length;
(*format->move)(ref, newRef); /* .exposed.seg */
} else {
/* reference to broken heart (which should be snapped out -- */
/* consider adding to (non-existant) snap-out cache here) */
STATISTIC_STAT(++ss->snapCount);
}
/* .fix.update: update the reference to whatever the above code */
/* decided it should be */
updateReference:
*refIO = newRef;
res = ResOK;
returnRes:
ShieldCover(arena, seg); /* .exposed.seg */
return res;
}
/* AMCHeaderFix -- fix a reference to the pool, with headers
*
* See <design/poolamc/#header.fix>.
*/
static Res AMCHeaderFix(Pool pool, ScanState ss, Seg seg, Ref *refIO)
{
Arena arena;
AMC amc;
Res res;
Format format; /* cache of pool->format */
Ref ref; /* reference to be fixed */
Ref newRef; /* new location, if moved */
Addr newBase; /* base address of new copy */
Size length; /* length of object to be relocated */
Buffer buffer; /* buffer to allocate new copy into */
amcGen gen; /* generation of old copy of object */
TraceSet grey; /* greyness of object being relocated */
TraceSet toGrey; /* greyness of object's destination */
RefSet summary; /* summary of object being relocated */
RefSet toSummary; /* summary of object's destination */
Seg toSeg; /* segment to which object is being relocated */
/* <design/trace/#fix.noaver> */
AVERT_CRITICAL(Pool, pool);
AVERT_CRITICAL(ScanState, ss);
AVERT_CRITICAL(Seg, seg);
AVER_CRITICAL(refIO != NULL);
EVENT_0(AMCFix);
/* For the moment, assume that the object was already marked. */
/* (See <design/fix/#protocol.was-marked>.) */
ss->wasMarked = TRUE;
/* If the reference is ambiguous, set up the datastructures for */
/* managing a nailed segment. This involves marking the segment */
/* as nailed, and setting up a per-word mark table */
if(ss->rank == RankAMBIG) {
/* .nail.new: Check to see whether we need a Nailboard for */
/* this seg. We use "SegNailed(seg) == TraceSetEMPTY" */
/* rather than "!amcSegHasNailboard(seg)" because this avoids */
/* setting up a new nailboard when the segment was nailed, but */
/* had no nailboard. This must be avoided because otherwise */
/* assumptions in AMCFixEmergency will be wrong (essentially */
/* we will lose some pointer fixes because we introduced a */
/* nailboard). */
if(SegNailed(seg) == TraceSetEMPTY) {
res = amcSegCreateNailboard(seg, pool);
if(res != ResOK)
return res;
++ss->nailCount;
SegSetNailed(seg, TraceSetUnion(SegNailed(seg), ss->traces));
}
amcFixInPlace(pool, seg, ss, refIO);
return ResOK;
}
amc = Pool2AMC(pool);
AVERT_CRITICAL(AMC, amc);
format = pool->format;
ref = *refIO;
AVER_CRITICAL(AddrAdd(SegBase(seg), pool->format->headerSize)
<= ref);
AVER_CRITICAL(ref < SegLimit(seg)); /* see .ref-limit */
arena = pool->arena;
/* .exposed.seg: Statements tagged ".exposed.seg" below require */
/* that "seg" (that is: the 'from' seg) has been ShieldExposed. */
ShieldExpose(arena, seg);
newRef = (*format->isMoved)(ref); /* .exposed.seg */
if(newRef == (Addr)0) {
/* If object is nailed already then we mustn't copy it: */
if(SegNailed(seg) != TraceSetEMPTY
&& (!amcSegHasNailboard(seg) || amcNailGetMark(seg, ref))) {
/* Segment only needs greying if there are new traces for */
/* which we are nailing. */
if(!TraceSetSub(ss->traces, SegNailed(seg))) {
if(SegRankSet(seg) != RankSetEMPTY)
SegSetGrey(seg, TraceSetUnion(SegGrey(seg), ss->traces));
SegSetNailed(seg, TraceSetUnion(SegNailed(seg), ss->traces));
}
res = ResOK;
goto returnRes;
} else if(ss->rank == RankWEAK) {
/* object is not preserved (neither moved, nor nailed) */
/* hence, reference should be splatted */
goto updateReference;
}
/* object is not preserved yet (neither moved, nor nailed) */
/* so should be preserved by forwarding */
EVENT_A(AMCFixForward, newRef);
/* <design/fix/#protocol.was-marked> */
ss->wasMarked = FALSE;
/* Get the forwarding buffer from the object's generation. */
gen = amcSegGen(seg);
buffer = gen->forward;
AVER_CRITICAL(buffer != NULL);
length = AddrOffset(ref, (*format->skip)(ref)); /* .exposed.seg */
STATISTIC_STAT(++ss->forwardedCount);
ss->forwardedSize += length;
do {
Size headerSize = format->headerSize;
res = BUFFER_RESERVE(&newBase, buffer, length, FALSE);
if (res != ResOK)
goto returnRes;
newRef = AddrAdd(newBase, headerSize);
toSeg = BufferSeg(buffer);
ShieldExpose(arena, toSeg);
/* Since we're moving an object from one segment to another, */
/* union the greyness and the summaries together. */
grey = TraceSetUnion(ss->traces, SegGrey(seg));
toGrey = SegGrey(toSeg);
if(TraceSetDiff(grey, toGrey) != TraceSetEMPTY
&& SegRankSet(seg) != RankSetEMPTY)
SegSetGrey(toSeg, TraceSetUnion(toGrey, grey));
summary = SegSummary(seg);
toSummary = SegSummary(toSeg);
if(RefSetDiff(summary, toSummary) != RefSetEMPTY)
SegSetSummary(toSeg, RefSetUnion(toSummary, summary));
/* <design/trace/#fix.copy> */
(void)AddrCopy(newBase, AddrSub(ref, headerSize), length); /* .exposed.seg */
ShieldCover(arena, toSeg);
} while (!BUFFER_COMMIT(buffer, newBase, length));
ss->copiedSize += length;
(*format->move)(ref, newRef); /* .exposed.seg */
} else {
/* reference to broken heart (which should be snapped out -- */
/* consider adding to (non-existent) snap-out cache here) */
STATISTIC_STAT(++ss->snapCount);
}
/* .fix.update: update the reference to whatever the above code */
/* decided it should be */
updateReference:
*refIO = newRef;
res = ResOK;
returnRes:
ShieldCover(arena, seg); /* .exposed.seg */
return res;
}
/* amcReclaimNailed -- reclaim what you can from a nailed segment */
static void amcReclaimNailed(Pool pool, Trace trace, Seg seg)
{
Addr p, limit;
Arena arena;
Format format;
Size bytesReclaimed = (Size)0;
Count preservedInPlaceCount = (Count)0;
Size preservedInPlaceSize = (Size)0;
AMC amc;
Size headerSize;
Addr p1; /* first obj in seg */
Bool obj1pip = FALSE; /* first obj was preserved in place */
/* All arguments AVERed by AMCReclaim */
amc = Pool2AMC(pool);
AVERT(AMC, amc);
format = pool->format;
arena = PoolArena(pool);
AVERT(Arena, arena);
/* see <design/poolamc/#nailboard.limitations> for improvements */
headerSize = format->headerSize;
ShieldExpose(arena, seg);
p = AddrAdd(SegBase(seg), headerSize);
if(SegBuffer(seg) != NULL) {
limit = BufferScanLimit(SegBuffer(seg));
} else {
limit = SegLimit(seg);
}
limit = AddrAdd(limit, headerSize);
p1 = p;
while(p < limit) {
Addr q;
Size length;
q = (*format->skip)(p);
length = AddrOffset(p, q);
if(amcSegHasNailboard(seg)
? !amcNailGetMark(seg, p)
/* If there's no mark table, retain all that hasn't been */
/* forwarded. In this case, preservedInPlace* become */
/* somewhat overstated. */
: (*format->isMoved)(p) != NULL)
{
/* Replace forwarding pointer / unreachable object with pad */
(*format->pad)(AddrSub(p, headerSize), length);
bytesReclaimed += length;
} else {
++preservedInPlaceCount;
preservedInPlaceSize += length;
if(p == p1)
obj1pip = TRUE;
}
AVER(p < q);
p = q;
}
AVER(p == limit);
ShieldCover(arena, seg);
SegSetNailed(seg, TraceSetDel(SegNailed(seg), trace));
SegSetWhite(seg, TraceSetDel(SegWhite(seg), trace));
if(SegNailed(seg) == TraceSetEMPTY && amcSegHasNailboard(seg)) {
amcSegDestroyNailboard(seg, pool);
}
AVER(bytesReclaimed <= SegSize(seg));
trace->reclaimSize += bytesReclaimed;
trace->preservedInPlaceCount += preservedInPlaceCount;
trace->preservedInPlaceSize += preservedInPlaceSize;
/* Free the seg if we can; fixes .nailboard.limitations.middle. */
if(preservedInPlaceCount == 0
&& (SegBuffer(seg) == NULL)
&& (SegNailed(seg) == TraceSetEMPTY)) {
amcGen gen = amcSegGen(seg);
/* We may not free a buffered seg. */
AVER(SegBuffer(seg) == NULL);
--gen->segs;
gen->pgen.totalSize -= SegSize(seg);
SegFree(seg);
} else {
/* Seg retained */
STATISTIC_STAT( {
Count pages;
AVER(SizeIsAligned(SegSize(seg), ArenaAlign(pool->arena)));
pages = SegSize(seg) / ArenaAlign(pool->arena);
AVER(pages != 0);
amc->pageretstruct[trace->ti].pRet += pages;
if(pages == 1) {
amc->pageretstruct[trace->ti].pRS += pages;
} else if(pages < AMCLargeSegPAGES) {
amc->pageretstruct[trace->ti].sRM += 1;
amc->pageretstruct[trace->ti].pRM += pages;
if(obj1pip) {
amc->pageretstruct[trace->ti].pRM1 += pages;
} else {
/* Seg retained by a rest obj. Cost: one rest page, */
/* plus pages-1 pages of pure padding. */
amc->pageretstruct[trace->ti].pRMrr += 1;
amc->pageretstruct[trace->ti].pRMr1 += pages - 1;
}
} else {
amc->pageretstruct[trace->ti].sRL += 1;
amc->pageretstruct[trace->ti].pRL += pages;
if(!obj1pip) {
/* Seg retained by a rest obj */
amc->pageretstruct[trace->ti].pRLr += pages;
}
}
} );
}
}
/* AMCReclaim -- recycle a segment if it is still white
*
* See <design/poolamc/#reclaim>.
*/
static void AMCReclaim(Pool pool, Trace trace, Seg seg)
{
AMC amc;
amcGen gen;
Size size;
AVERT_CRITICAL(Pool, pool);
amc = Pool2AMC(pool);
AVERT_CRITICAL(AMC, amc);
AVERT_CRITICAL(Trace, trace);
AVERT_CRITICAL(Seg, seg);
gen = amcSegGen(seg);
AVERT_CRITICAL(amcGen, gen);
EVENT_PPP(AMCReclaim, gen, trace, seg);
/* This switching needs to be more complex for multiple traces. */
AVER_CRITICAL(TraceSetIsSingle(PoolArena(pool)->busyTraces));
if(amc->rampMode == RampCOLLECTING) {
if(amc->rampCount > 0) {
/* Entered ramp mode before previous one was cleaned up */
amc->rampMode = RampBEGIN;
} else {
amc->rampMode = RampOUTSIDE;
}
}
if(SegNailed(seg) != TraceSetEMPTY) {
amcReclaimNailed(pool, trace, seg);
return;
}
/* We may not free a buffered seg. (But all buffered + condemned */
/* segs should have been nailed anyway). */
AVER(SegBuffer(seg) == NULL);
--gen->segs;
size = SegSize(seg);
gen->pgen.totalSize -= size;
trace->reclaimSize += size;
SegFree(seg);
}
/* AMCTraceEnd -- emit end-of-trace diagnostics
*
*/
static void AMCTraceEnd(Pool pool, Trace trace)
{
AMC amc;
TraceId ti;
Count pRetMin = 100;
AVERT(Pool, pool);
AVERT(Trace, trace);
amc = Pool2AMC(pool);
AVERT(AMC, amc);
ti = trace->ti;
AVER(TraceIdCheck(ti));
if(amc->pageretstruct[ti].pRet >= pRetMin) {
DIAG_SINGLEF(( "AMCTraceEnd_pageret",
" $U", ArenaEpoch(pool->arena),
" $U", trace->why,
" $S", trace->emergency ? "Emergency" : "-",
" $U", amc->pageretstruct[ti].pCond,
" $U", amc->pageretstruct[ti].pRet, ",",
" $U", amc->pageretstruct[ti].pCS,
" $U", amc->pageretstruct[ti].pRS, ",",
" $U", amc->pageretstruct[ti].sCM,
" $U", amc->pageretstruct[ti].pCM,
" $U", amc->pageretstruct[ti].sRM,
" $U", amc->pageretstruct[ti].pRM,
" $U", amc->pageretstruct[ti].pRM1,
" $U", amc->pageretstruct[ti].pRMrr,
" $U", amc->pageretstruct[ti].pRMr1, ",",
" $U", amc->pageretstruct[ti].sCL,
" $U", amc->pageretstruct[ti].pCL,
" $U", amc->pageretstruct[ti].sRL,
" $U", amc->pageretstruct[ti].pRL,
" $U", amc->pageretstruct[ti].pRLr,
" (page = $Ub,", ArenaAlign(pool->arena),
" Large >= $Up,", AMCLargeSegPAGES,
" pRetMin $U)", pRetMin,
NULL ));
}
STATISTIC(amc->pageretstruct[ti] = pageretstruct_Zero);
}
/* AMCWalk -- Apply function to (black) objects in segment */
static void AMCWalk(Pool pool, Seg seg, FormattedObjectsStepMethod f,
void *p, unsigned long s)
{
Addr object, nextObject, limit;
AMC amc;
Format format;
AVERT(Pool, pool);
AVERT(Seg, seg);
AVER(FUNCHECK(f));
/* p and s are arbitrary closures so can't be checked */
/* Avoid applying the function to grey or white objects. */
/* White objects might not be alive, and grey objects */
/* may have pointers to old-space. */
/* NB, segments containing a mix of colours (i.e., nailed segs) */
/* are not handled properly: No objects are walked. See */
/* job001682. */
if(SegWhite(seg) == TraceSetEMPTY && SegGrey(seg) == TraceSetEMPTY
&& SegNailed(seg) == TraceSetEMPTY)
{
amc = Pool2AMC(pool);
AVERT(AMC, amc);
format = pool->format;
/* If the segment is buffered, only walk as far as the end */
/* of the initialized objects. cf. AMCScan */
if(SegBuffer(seg) != NULL)
limit = BufferScanLimit(SegBuffer(seg));
else
limit = SegLimit(seg);
limit = AddrAdd(limit, format->headerSize);
object = AddrAdd(SegBase(seg), format->headerSize);
while(object < limit) {
/* Check not a broken heart. */
AVER((*format->isMoved)(object) == NULL);
(*f)(object, pool->format, pool, p, s);
nextObject = (*pool->format->skip)(object);
AVER(nextObject > object);
object = nextObject;
}
AVER(object == limit);
}
}
/* amcWalkAll -- Apply a function to all (black) objects in a pool */
static void amcWalkAll(Pool pool, FormattedObjectsStepMethod f,
void *p, unsigned long s)
{
Arena arena;
Ring ring, next, node;
AVER(IsSubclassPoly(pool->class, AMCPoolClassGet()));
arena = PoolArena(pool);
ring = PoolSegRing(pool);
node = RingNext(ring);
RING_FOR(node, ring, next) {
Seg seg = SegOfPoolRing(node);
ShieldExpose(arena, seg);
AMCWalk(pool, seg, f, p, s);
ShieldCover(arena, seg);
}
}
/* AMCDescribe -- describe the contents of the AMC pool
*
* See <design/poolamc/#describe>.
*/
static Res AMCDescribe(Pool pool, mps_lib_FILE *stream)
{
Res res;
AMC amc;
Ring node, nextNode;
char *rampmode;
if(!CHECKT(Pool, pool))
return ResFAIL;
amc = Pool2AMC(pool);
if(!CHECKT(AMC, amc))
return ResFAIL;
if(stream == NULL)
return ResFAIL;
res = WriteF(stream,
(amc->rankSet == RankSetEMPTY) ? "AMCZ" : "AMC",
" $P {\n", (WriteFP)amc, " pool $P ($U)\n",
(WriteFP)AMC2Pool(amc), (WriteFU)AMC2Pool(amc)->serial,
NULL);
if(res != ResOK)
return res;
switch(amc->rampMode) {
#define RAMP_DESCRIBE(e, s) \
case e: \
rampmode = s; \
break;
RAMP_RELATION(RAMP_DESCRIBE)
#undef RAMP_DESCRIBE
default:
rampmode = "unknown ramp mode";
break;
}
res = WriteF(stream,
" ", rampmode, " ($U)\n", (WriteFU)amc->rampCount,
NULL);
if(res != ResOK)
return res;
RING_FOR(node, &amc->genRing, nextNode) {
amcGen gen = RING_ELT(amcGen, amcRing, node);
res = amcGenDescribe(gen, stream);
if(res != ResOK)
return res;
}
if(0) {
/* SegDescribes */
RING_FOR(node, &AMC2Pool(amc)->segRing, nextNode) {
Seg seg = RING_ELT(Seg, poolRing, node);
res = AMCSegDescribe(seg, stream);
if(res != ResOK)
return res;
}
}
res = WriteF(stream, "} AMC $P\n", (WriteFP)amc, NULL);
if(res != ResOK)
return res;
return ResOK;
}
/* AMCPoolClass -- the class definition */
DEFINE_POOL_CLASS(AMCPoolClass, this)
{
INHERIT_CLASS(this, AbstractCollectPoolClass);
PoolClassMixInFormat(this);
this->name = "AMC";
this->size = sizeof(AMCStruct);
this->offset = offsetof(AMCStruct, poolStruct);
this->attr |= AttrMOVINGGC;
this->init = AMCInit;
this->finish = AMCFinish;
this->bufferFill = AMCBufferFill;
this->bufferEmpty = AMCBufferEmpty;
this->whiten = AMCWhiten;
this->scan = AMCScan;
this->fix = AMCFix;
this->fixEmergency = AMCFixEmergency;
this->reclaim = AMCReclaim;
this->traceEnd = AMCTraceEnd;
this->rampBegin = AMCRampBegin;
this->rampEnd = AMCRampEnd;
this->walk = AMCWalk;
this->bufferClass = amcBufClassGet;
this->describe = AMCDescribe;
}
/* AMCZPoolClass -- the class definition */
DEFINE_POOL_CLASS(AMCZPoolClass, this)
{
INHERIT_CLASS(this, AMCPoolClass);
this->name = "AMCZ";
this->attr &= ~(AttrSCAN | AttrINCR_RB);
this->init = AMCZInit;
this->grey = PoolNoGrey;
this->scan = PoolNoScan;
}
/* mps_class_amc -- return the pool class descriptor to the client */
mps_class_t mps_class_amc(void)
{
return (mps_class_t)AMCPoolClassGet();
}
/* mps_class_amcz -- return the pool class descriptor to the client */
mps_class_t mps_class_amcz(void)
{
return (mps_class_t)AMCZPoolClassGet();
}
/* mps_amc_apply -- apply function to all objects in pool
*
* The iterator that is passed by the client is stored in a closure
* structure which is passed to a local iterator in order to ensure
* that any type conversion necessary between Addr and mps_addr_t
* happen. They are almost certainly the same on all platforms, but
* this is the correct way to do it.
*/
typedef struct mps_amc_apply_closure_s {
void (*f)(mps_addr_t object, void *p, size_t s);
void *p;
size_t s;
} mps_amc_apply_closure_s;
static void mps_amc_apply_iter(Addr addr, Format format, Pool pool,
void *p, unsigned long s)
{
mps_amc_apply_closure_s *closure = p;
/* Can't check addr */
AVERT(Format, format);
AVERT(Pool, pool);
/* We could check that s is the sizeof *p, but it would be slow */
UNUSED(format);
UNUSED(pool);
UNUSED(s);
(*closure->f)(addr, closure->p, closure->s);
}
void mps_amc_apply(mps_pool_t mps_pool,
void (*f)(mps_addr_t object, void *p, size_t s),
void *p, size_t s)
{
Pool pool = (Pool)mps_pool;
mps_amc_apply_closure_s closure_s;
Arena arena;
AVER(CHECKT(Pool, pool));
arena = PoolArena(pool);
ArenaEnter(arena);
AVERT(Pool, pool);
closure_s.f = f;
closure_s.p = p;
closure_s.s = s;
amcWalkAll(pool, mps_amc_apply_iter, &closure_s, sizeof(closure_s));
ArenaLeave(arena);
}
/* AMCCheck -- check consistency of the AMC pool
*
* See <design/poolamc/#check>.
*/
static Bool AMCCheck(AMC amc)
{
CHECKS(AMC, amc);
CHECKD(Pool, &amc->poolStruct);
CHECKL(IsSubclassPoly(amc->poolStruct.class, EnsureAMCPoolClass()));
CHECKL(RankSetCheck(amc->rankSet));
CHECKL(RingCheck(&amc->genRing));
CHECKL(BoolCheck(amc->gensBooted));
if(amc->gensBooted) {
CHECKD(amcGen, amc->nursery);
CHECKL(amc->gen != NULL);
CHECKD(amcGen, amc->rampGen);
CHECKD(amcGen, amc->afterRampGen);
}
/* nothing to check for rampCount */
CHECKL(amc->rampMode >= RampOUTSIDE);
CHECKL(amc->rampMode <= RampCOLLECTING);
/* pageretstruct[ti] is statistics only, currently unchecked */
return TRUE;
}
/* C. COPYRIGHT AND LICENSE
*
* Copyright (C) 2001-2002, 2008 Ravenbrook Limited <http://www.ravenbrook.com/>.
* All rights reserved. This is an open source license. Contact
* Ravenbrook for commercial licensing options.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Redistributions in any form must be accompanied by information on how
* to obtain complete source code for this software and any accompanying
* software that uses this software. The source code must either be
* included in the distribution or be available for no more than the cost
* of distribution plus a nominal fee, and must be freely redistributable
* under reasonable conditions. For an executable file, complete source
* code means the source code for all modules it contains. It does not
* include source code for modules or files that typically accompany the
* major components of the operating system on which the executable file
* runs.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
* PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/