uGFX/ugfx
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Update the Raw32 heap allocator to remove a memory merging bug.

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The new code has less allocation overhead but memory blocks are now not tracked while allocated.
This commit is contained in:
inmarket 2016-12-12 20:01:27 +10:00
parent bc7a2b05c1
commit f495b49f53
2 changed files with 52 additions and 62 deletions
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2
docs/changelog.txt
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@ -29,6 +29,8 @@ FEATURE: Added the ability to display the detected compiler
FIX: Fixed an illegal instruction in the Cortex M0 task switcher
FEATURE: Added RAW32 task switching functions which work with ARMCC (the compiler used by Keil) for Cortex M0,M1,M3,M4 and M7
FEATURE: Added gdispGDrawThickArc()
FIX: Fix a memory merging issue with the RAW32 memory allocator
FIX: Update RAW32 CLIB threads support for more recent versions of the MINGW compiler
*** Release 2.6 ***

112
src/gos/gos_x_heap.c
View File

@ -34,7 +34,6 @@
// Slot structure - user memory follows
typedef struct memslot {
struct memslot *next; // The next memslot
size_t sz; // Includes the size of this memslot.
} memslot;
@ -48,13 +47,10 @@
#define Ptr2Slot(p) ((memslot *)(p) - 1)
#define Slot2Ptr(pslot) ((pslot)+1)
static memslot * firstSlot;
static memslot * lastSlot;
static memslot * freeSlots;
static char heap[GFX_OS_HEAP_SIZE];
void _gosHeapInit(void) {
lastSlot = 0;
gfxAddHeapBlock(heap, GFX_OS_HEAP_SIZE);
}
@ -62,18 +58,12 @@
if (sz < sizeof(memslot)+sizeof(freeslot))
return;
if (lastSlot)
lastSlot->next = (memslot *)ptr;
else
firstSlot = lastSlot = freeSlots = (memslot *)ptr;
lastSlot->next = 0;
lastSlot->sz = sz;
NextFree(lastSlot) = 0;
((memslot *)ptr)->sz = sz;
gfxFree(Slot2Ptr((memslot *)ptr));
}
void *gfxAlloc(size_t sz) {
register memslot *prev, *p, *new;
register memslot *prev, *p, *pnew;
if (!sz) return 0;
sz = GetSlotSize(sz);
@ -81,23 +71,22 @@
// Loop till we have a block big enough
if (p->sz < sz)
continue;
// Can we save some memory by splitting this block?
if (p->sz >= sz + sizeof(memslot)+sizeof(freeslot)) {
new = (memslot *)((char *)p + sz);
new->next = p->next;
p->next = new;
new->sz = p->sz - sz;
pnew = (memslot *)((char *)p + sz);
pnew->sz = p->sz - sz;
p->sz = sz;
if (lastSlot == p)
lastSlot = new;
NextFree(new) = NextFree(p);
NextFree(p) = new;
NextFree(pnew) = NextFree(p);
NextFree(p) = pnew;
}
// Remove it from the free list
if (prev)
NextFree(prev) = NextFree(p);
else
freeSlots = NextFree(p);
// Return the result found
return Slot2Ptr(p);
}
@ -106,7 +95,7 @@
}
void *gfxRealloc(void *ptr, size_t oldsz, size_t sz) {
register memslot *prev, *p, *new;
register memslot *prev, *p, *pfree;
(void) oldsz;
if (!ptr)
@ -120,19 +109,14 @@
sz = GetSlotSize(sz);
// If the next slot is free (and contiguous) merge it into this one
if ((char *)p + p->sz == (char *)p->next) {
for (prev = 0, new = freeSlots; new != 0; prev = new, new = NextFree(new)) {
if (new == p->next) {
p->next = new->next;
p->sz += new->sz;
if (prev)
NextFree(prev) = NextFree(new);
else
freeSlots = NextFree(new);
if (lastSlot == new)
lastSlot = p;
break;
}
for (prev = 0, pfree = freeSlots; pfree != 0; prev = pfree, pfree = NextFree(pfree)) {
if (pfree == (memslot *)((char *)p + p->sz)) {
p->sz += pfree->sz;
if (prev)
NextFree(prev) = NextFree(pfree);
else
freeSlots = NextFree(pfree);
break;
}
}
@ -140,50 +124,54 @@
if (sz < p->sz) {
// Can we save some memory by splitting this block?
if (p->sz >= sz + sizeof(memslot)+sizeof(freeslot)) {
new = (memslot *)((char *)p + sz);
new->next = p->next;
p->next = new;
new->sz = p->sz - sz;
pfree = (memslot *)((char *)p + sz);
pfree->sz = p->sz - sz;
p->sz = sz;
if (lastSlot == p)
lastSlot = new;
NextFree(new) = freeSlots;
freeSlots = new;
NextFree(pfree) = freeSlots;
freeSlots = pfree;
}
return Slot2Ptr(p);
}
// We need to do this the hard way
new = gfxAlloc(sz);
if (new)
pfree = gfxAlloc(sz);
if (pfree)
return 0;
memcpy(new, ptr, p->sz - sizeof(memslot));
memcpy(pfree, ptr, p->sz - sizeof(memslot));
gfxFree(ptr);
return new;
return pfree;
}
void gfxFree(void *ptr) {
register memslot *prev, *p, *new;
register memslot *prev, *p, *pfree;
if (!ptr)
return;
p = Ptr2Slot(ptr);
// If the next slot is free (and contiguous) merge it into this one
if ((char *)p + p->sz == (char *)p->next) {
for (prev = 0, new = freeSlots; new != 0; prev = new, new = NextFree(new)) {
if (new == p->next) {
p->next = new->next;
p->sz += new->sz;
if (prev)
NextFree(prev) = NextFree(new);
else
freeSlots = NextFree(new);
if (lastSlot == new)
lastSlot = p;
break;
}
// Find a free slot that is contiguous precceding and merge it into us
for (prev = 0, pfree = freeSlots; pfree != 0; prev = pfree, pfree = NextFree(pfree)) {
if (p == (memslot *)((char *)pfree + pfree->sz)) {
pfree->sz += p->sz;
if (prev)
NextFree(prev) = NextFree(pfree);
else
freeSlots = NextFree(pfree);
p = pfree;
break;
}
}
// Find a free slot that is contiguous after and merge it into this one
for (prev = 0, pfree = freeSlots; pfree != 0; prev = pfree, pfree = NextFree(pfree)) {
if (pfree == (memslot *)((char *)p + p->sz)) {
p->sz += pfree->sz;
if (prev)
NextFree(prev) = NextFree(pfree);
else
freeSlots = NextFree(pfree);
break;
}
}