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Commit 239a0ceb authored by John Hodge's avatar John Hodge
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Kernel/heap - Clean up a little, fix corruption in realloc, add hacky watchpoints

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KernelLand/Kernel/heap.c
+ 146
− 29
View file @ 239a0ceb
......@@ -34,10 +34,13 @@
void Heap_Install(void);
void *Heap_Extend(size_t Bytes);
void *Heap_Merge(tHeapHead *Head);
static const size_t Heap_int_GetBlockSize(size_t AllocSize);
//void *Heap_Allocate(const char *File, int Line, size_t Bytes);
//void *Heap_AllocateZero(const char *File, int Line, size_t Bytes);
//void *Heap_Reallocate(const char *File, int Line, void *Ptr, size_t Bytes);
//void Heap_Deallocate(const char *File, int Line, void *Ptr);
int Heap_int_ApplyWatchpont(void *Addr, bool Enabled);
void Heap_int_WatchBlock(tHeapHead *Head, bool Enabled);
//void Heap_Dump(void);
void Heap_ValidateDump(int bVerbose);
//void Heap_Stats(void);
......@@ -124,20 +127,15 @@ void *Heap_Extend(size_t Bytes)
*/
void *Heap_Merge(tHeapHead *Head)
{
tHeapFoot *foot;
tHeapFoot *thisFoot;
tHeapHead *head;
//Log("Heap_Merge: (Head=%p)", Head);
tHeapFoot *thisFoot = Heap_ThisFoot(Head);
thisFoot = Heap_ThisFoot(Head);
if( (void*)thisFoot > (void*)gHeapEnd )
return NULL;
ASSERT( Heap_NextHead(Head) <= gHeapEnd );
// Merge Left (Down)
foot = Heap_PrevFoot(Head);
if( ((Uint)foot < (Uint)gHeapEnd && (Uint)foot > (Uint)gHeapStart)
&& foot->Head->Magic == MAGIC_FREE) {
tHeapFoot *foot = Heap_PrevFoot(Head);
if( Head > gHeapStart && foot->Head->Magic == MAGIC_FREE)
{
foot->Head->Size += Head->Size; // Increase size
thisFoot->Head = foot->Head; // Change backlink
Head->Magic = 0; // Clear old head
......@@ -148,22 +146,34 @@ void *Heap_Merge(tHeapHead *Head)
}
// Merge Right (Upwards)
head = Heap_NextHead(Head);
if((Uint)head < (Uint)gHeapEnd && head->Magic == MAGIC_FREE)
tHeapHead *nexthead = Heap_NextHead(Head);
if(nexthead < gHeapEnd && nexthead->Magic == MAGIC_FREE)
{
Head->Size += head->Size;
Head->Size += nexthead->Size;
foot = Heap_ThisFoot(Head);
foot->Head = Head; // Update Backlink
thisFoot->Head = NULL; // Clear old footer
thisFoot->Magic = 0;
head->Size = 0; // Clear old header
head->Magic = 0;
nexthead->Size = 0; // Clear old header
nexthead->Magic = 0;
}
// Return new address
return Head;
}
static const size_t Heap_int_GetBlockSize(size_t AllocSize)
{
size_t Bytes;
#if POW2_SIZES
Bytes = AllocSize + sizeof(tHeapHead) + sizeof(tHeapFoot);
Bytes = 1UUL << LOG2(Bytes);
#else
Bytes = (AllocSize + sizeof(tHeapHead) + sizeof(tHeapFoot) + MIN_SIZE-1) & ~(MIN_SIZE-1);
#endif
return Bytes;
}
/**
* \param File Allocating source file
* \param Line Source line
......@@ -187,12 +197,7 @@ void *Heap_Allocate(const char *File, int Line, size_t __Bytes)
#endif
// Get required size
#if POW2_SIZES
Bytes = __Bytes + sizeof(tHeapHead) + sizeof(tHeapFoot);
Bytes = 1UUL << LOG2(__Bytes);
#else
Bytes = (__Bytes + sizeof(tHeapHead) + sizeof(tHeapFoot) + MIN_SIZE-1) & ~(MIN_SIZE-1);
#endif
Bytes = Heap_int_GetBlockSize(__Bytes);
// Lock Heap
Mutex_Acquire(&glHeap);
......@@ -217,18 +222,22 @@ void *Heap_Allocate(const char *File, int Line, size_t __Bytes)
}
if( head->Size < MIN_SIZE ) {
Mutex_Release(&glHeap);
#if WARNINGS
Log_Warning("Heap", "Size of heap address %p is invalid"
" - Too small (0x%x) [at paddr 0x%x]",
head, head->Size, MM_GetPhysAddr(&head->Size));
Heap_ValidateDump(VERBOSE_DUMP);
#endif
return NULL;
}
if( head->Size > (2<<30) ) {
Mutex_Release(&glHeap);
#if WARNINGS
Log_Warning("Heap", "Size of heap address %p is invalid"
" - Over 2GiB (0x%x) [at paddr 0x%x]",
head, head->Size, MM_GetPhysAddr(&head->Size));
Heap_ValidateDump(VERBOSE_DUMP);
#endif
return NULL;
}
......@@ -360,7 +369,7 @@ void Heap_Deallocate(const char *File, int Line, void *Ptr)
}
// Check memory block - Header
tHeapHead *head = (void*)( (Uint)Ptr - sizeof(tHeapHead) );
tHeapHead *head = (tHeapHead*)Ptr - 1;
if(head->Magic == MAGIC_FREE) {
Log_Warning("Heap", "free - Passed a freed block (%p) by %s:%i (was freed by %s:%i)",
head, File, Line,
......@@ -395,7 +404,9 @@ void Heap_Deallocate(const char *File, int Line, void *Ptr)
// Lock
Mutex_Acquire( &glHeap );
Heap_int_WatchBlock(head, false);
// Mark as free
head->Magic = MAGIC_FREE;
head->File = File;
......@@ -417,16 +428,36 @@ void Heap_Deallocate(const char *File, int Line, void *Ptr)
*/
void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
{
tHeapHead *head = (void*)( (Uint)__ptr-sizeof(tHeapHead) );
tHeapHead *head = (tHeapHead*)__ptr - 1;
tHeapHead *nextHead;
tHeapFoot *foot;
Uint newSize = (__size + sizeof(tHeapFoot)+sizeof(tHeapHead)+MIN_SIZE-1)&~(MIN_SIZE-1);
Uint newSize = Heap_int_GetBlockSize(__size);
// Check for reallocating NULL
if(__ptr == NULL) return Heap_Allocate(File, Line, __size);
if(__ptr == NULL)
return Heap_Allocate(File, Line, __size);
if( !Heap_IsHeapAddr(__ptr)) {
Log_Error("Heap", "%s:%i passed non-heap address %p when reallocating to %zi",
File, Line, __ptr, __size);
return NULL;
}
// Check if resize is needed
if(newSize <= head->Size) return __ptr;
// TODO: Reduce size of block if needed
if(newSize <= head->Size) {
#if DEBUG_TRACE
Log_Debug("Heap", "realloc maintain %p (0x%x >= 0x%x), returning to %s:%i",
head->Data, head->Size, newSize, File, Line);
#endif
return __ptr;
}
#if VALIDATE_ON_ALLOC
Heap_Validate();
#endif
Heap_int_WatchBlock(head, false);
// Check if next block is free
nextHead = Heap_NextHead(head);
......@@ -434,6 +465,10 @@ void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
// Extend into next block
if(nextHead->Magic == MAGIC_FREE && nextHead->Size+head->Size >= newSize)
{
#if DEBUG_TRACE
Log_Debug("Heap", "realloc expand %p (0x%x to 0x%x), returning to %s:%i",
head->Data, head->Size, newSize, File, Line);
#endif
Uint size = nextHead->Size + head->Size;
foot = Heap_ThisFoot(nextHead);
// Exact Fit
......@@ -462,7 +497,7 @@ void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
nextHead->Size = size - newSize;
nextHead->Magic = MAGIC_FREE;
// - Update old footer
foot->Head = nextHead;
Heap_ThisFoot(nextHead)->Head = nextHead;
return __ptr;
}
......@@ -479,6 +514,11 @@ void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
Warning("[Heap ] TODO: Space efficient realloc when new size is smaller");
}
#if DEBUG_TRACE
Log_Debug("Heap", "realloc expand down %p (0x%x to 0x%x), returning to %s:%i",
head->Data, head->Size, newSize, File, Line);
#endif
// Exact fit
Uint oldDataSize;
// Set 1st (new/lower) header
......@@ -509,6 +549,8 @@ void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
nextHead->Line = Line;
nextHead->ValidSize = __size;
ASSERTC(head->Size, <, nextHead->Size);
ASSERTC(__ptr, ==, head->Data);
memcpy(
nextHead->Data,
__ptr,
......@@ -516,7 +558,8 @@ void *Heap_Reallocate(const char *File, int Line, void *__ptr, size_t __size)
);
free(__ptr);
Heap_Validate();
return nextHead->Data;
}
......@@ -555,6 +598,80 @@ int Heap_IsHeapAddr(void *Ptr)
return 1;
}
int Heap_int_ApplyWatchpont(void *Word, bool enabled)
{
#if ARCHDIR_IS_x86
static void *active_wps[4];
unsigned int dr;
for( dr = 2; dr < 4; dr ++ )
{
if( (enabled && active_wps[dr] == NULL) || active_wps[dr] == Word)
break;
}
if(dr == 4) {
return 1;
}
if( enabled )
{
active_wps[dr] = Word;
switch(dr)
{
//case 0: ASM("mov %0, %%dr0" : : "r" (Word)); break;
//case 1: ASM("mov %0, %%dr1" : : "r" (Word)); break;
case 2: ASM("mov %0, %%dr2" : : "r" (Word)); break;
case 3: ASM("mov %0, %%dr3" : : "r" (Word)); break;
default: ASSERTC(dr,<,4); return 1;
}
}
else
{
active_wps[dr] = NULL;
}
Uint32 dr7flag;
ASM("MOV %%dr7, %0" : "=r" (dr7flag));
dr7flag &= ~(0x2 << (dr*2));
dr7flag &= ~(0xF000 << (dr*4));
if( enabled ) {
dr7flag |= 0x2 << (dr*2);
dr7flag |= 0xD000 << (dr*4); // 4 bytes, write
Debug("Heap_int_ApplyWatchpont: Watchpoint #%i %p ENABLED", dr, Word);
}
else {
Debug("Heap_int_ApplyWatchpont: Watchpoint #%i %p disabled", dr, Word);
}
ASM("MOV %0, %%dr7" : : "r" (dr7flag));
return 0;
#else
return 1;
#endif
}
void Heap_int_WatchBlock(tHeapHead *Head, bool Enabled)
{
int rv;
rv = Heap_int_ApplyWatchpont( &Head->Size, Enabled );
//rv = Heap_int_ApplyWatchpont( &Head->Magic, Enabled );
rv = rv + Heap_int_ApplyWatchpont( &Heap_ThisFoot(Head)->Head, Enabled );
if(rv && Enabled) {
Warning("Can't apply watch on %p", Head);
}
}
int Heap_WatchBlock(void *Ptr)
{
//Heap_int_ApplyWatchpont();
tHeapHead *head;
if((Uint)Ptr < (Uint)gHeapStart) return 0;
if((Uint)Ptr > (Uint)gHeapEnd) return 0;
if((Uint)Ptr & (sizeof(Uint)-1)) return 0;
head = (tHeapHead*)Ptr - 1;
Heap_int_WatchBlock( head, true );
return 0;
}
/**
*/
void Heap_Validate(void)
......
KernelLand/Kernel/include/heap.h
+ 6
− 0
View file @ 239a0ceb
......@@ -13,6 +13,12 @@ extern void *Heap_Reallocate(const char *File, int Line, void *Ptr, size_t Bytes
extern void Heap_Deallocate(const char *File, int Line, void *Ptr);
extern int Heap_IsHeapAddr(void *Ptr);
extern void Heap_Validate(void);
/**
* \brief Hint to the heap code to put a watchpoint on this block's memory
*
* Use sparingly, watchpoints are limited and/or very expensive (or not even implemented)
*/
extern int Heap_WatchBlock(void *Ptr);
#define malloc(size) Heap_Allocate(_MODULE_NAME_"/"__FILE__, __LINE__, (size))
#define calloc(num,size) Heap_AllocateZero(_MODULE_NAME_"/"__FILE__, __LINE__, (num)*(size))
......
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