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RegionAllocTracking: Add parameter to specify a maxmimum dynamic (non-fixed) memory address. Above this address, only fixed allocations are allowed

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This commit is contained in:
Jonathan Campbell
2021-10-17 14:13:38 -07:00
parent 932018299e
commit 68660a3fce
2 changed files with 64 additions and 91 deletions
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2
include/regionalloctracking.h
View File

@@ -17,6 +17,7 @@ public:
public:
RegionAllocTracking();
public:
void setMaxDynamicAllocationAddress(Bitu _new_max);
Bitu getMemory(Bitu bytes,const char *who,Bitu alignment,Bitu must_be_at);
void initSetRange(Bitu start,Bitu end);
Bitu freeUnusedMinToLoc(Bitu phys);
@@ -29,6 +30,7 @@ public:
std::string name;
std::vector<Block> alist;
Bitu _min,_max;
Bitu _max_nonfixed; /* above this address, only permit fixed memory allocation */
bool topDownAlloc;
public:
static const Bitu alloc_failed = ~((Bitu)0);

107
src/misc/regionalloctracking.cpp
View File

@@ -37,7 +37,14 @@ typedef SSIZE_T ssize_t;
RegionAllocTracking::Block::Block() : start(0), end(0), free(true) {
}
RegionAllocTracking::RegionAllocTracking() : _min(0), _max(~((Bitu)0)), topDownAlloc(false) {
RegionAllocTracking::RegionAllocTracking() : _min(0), _max(~((Bitu)0)), _max_nonfixed(~((Bitu)0)), topDownAlloc(false) {
}
void RegionAllocTracking::setMaxDynamicAllocationAddress(Bitu _new_max) {
if (_new_max != 0) /* nonzero to set */
_max_nonfixed = _new_max;
else /* zero to clear */
_max_nonfixed = ~((Bitu)0);
}
Bitu RegionAllocTracking::getMemory(Bitu bytes,const char *who,Bitu alignment,Bitu must_be_at) {
@@ -67,15 +74,41 @@ Bitu RegionAllocTracking::getMemory(Bitu bytes,const char *who,Bitu alignment,Bi
/* if must_be_at != 0 the caller wants a block at a very specific location */
if (must_be_at != 0) {
/* well, is there room to fit the forced block? if it starts before
* this block or the forced block would end past the block then, no. */
if (must_be_at < blk.start || (must_be_at+bytes-1u) > blk.end) {
base = must_be_at;
assert(alignment == 1u);
}
else {
if (topDownAlloc) {
base = blk.end + 1u - bytes; /* allocate downward from the top */
assert(base >= blk.start);
if (_max_nonfixed < _max) {
/* if instructed to by caller, disallow any dynamic allocation above a certain memory limit */
if ((_max_nonfixed + 1u) >= bytes) {
const Bitu nbase = _max_nonfixed + 1u - bytes;
if (base > nbase) base = nbase;
}
else {
base = 0;
}
}
}
else {
base = blk.start; /* allocate upward from the bottom */
assert(base <= blk.end);
base += alignment - 1u; /* alignment round up */
/* TODO: max_nonfixed... */
}
}
base &= ~(alignment - 1u); /* NTS: alignment == 16 means ~0xF or 0xFFFF0 */
if (base < blk.start || (base+bytes-1u) > blk.end) {
if (topDownAlloc) si--;
else si++;
continue;
}
base = must_be_at;
if (base == blk.start && (base+bytes-1u) == blk.end) { /* easy case: perfect match */
blk.free = false;
blk.who = who;
@@ -109,69 +142,6 @@ Bitu RegionAllocTracking::getMemory(Bitu bytes,const char *who,Bitu alignment,Bi
newblk2.who = who;
alist.insert(alist.begin()+(std::vector<RegionAllocTracking::Block>::difference_type)si+1u,newblk2);
}
}
else {
if (topDownAlloc) {
base = blk.end + 1u - bytes; /* allocate downward from the top */
assert(base >= blk.start);
}
else {
base = blk.start; /* allocate upward from the bottom */
assert(base <= blk.end);
base += alignment - 1u; /* alignment round up */
}
base &= ~(alignment - 1u); /* NTS: alignment == 16 means ~0xF or 0xFFFF0 */
if (base < blk.start || (base+bytes-1u) > blk.end) { /* if not possible after alignment, then skip */
if (topDownAlloc) si--;
else si++;
continue;
}
if (topDownAlloc) {
/* easy case: base matches start, just take the block! */
if (base == blk.start) {
blk.free = false;
blk.who = who;
return blk.start;
}
/* not-so-easy: need to split the block and claim the upper half */
RegionAllocTracking::Block newblk = blk; /* this becomes the new block we insert */
newblk.start = base;
newblk.free = false;
newblk.who = who;
blk.end = base - 1u;
if (blk.start > blk.end) {
sanityCheck();
abort();
}
alist.insert(alist.begin()+(std::vector<RegionAllocTracking::Block>::difference_type)si+1,newblk);
}
else {
if ((base+bytes-1u) == blk.end) {
blk.free = false;
blk.who = who;
return blk.start;
}
/* not-so-easy: need to split the block and claim the lower half */
RegionAllocTracking::Block newblk = blk; /* this becomes the new block we insert */
newblk.start = base+bytes;
blk.free = false;
blk.who = who;
blk.end = base+bytes-1u;
if (blk.start > blk.end) {
sanityCheck();
abort();
}
alist.insert(alist.begin()+(std::vector<RegionAllocTracking::Block>::difference_type)si+1u,newblk);
}
}
LOG(LOG_BIOS,LOG_DEBUG)("getMemory in '%s' (0x%05x bytes,\"%s\",align=%u,mustbe=0x%05x) = 0x%05x",name.c_str(),(int)bytes,who,(int)alignment,(int)must_be_at,(int)base);
sanityCheck();
@@ -210,6 +180,7 @@ void RegionAllocTracking::initSetRange(Bitu start,Bitu end) {
alist.clear();
_min = start;
_max = end;
_max_nonfixed = end;
x.end = _max;
x.free = true;