// allocate nbytes from the current slab, aligned to 16-bytes
void* MemoryManager::slabAlloc(size_t nbytes) {
const size_t kAlignMask = 15;
assert((nbytes & 7) == 0);
char* ptr = (char*)(uintptr_t(m_front + kAlignMask) & ~kAlignMask);
if (ptr + nbytes <= m_limit) {
m_front = ptr + nbytes;
return ptr;
}
return newSlab(nbytes);
}
/*
* Allocate `bytes' from the current slab, aligned to kSmartSizeAlign.
*/
void* MemoryManager::slabAlloc(uint32_t bytes, unsigned index) {
FTRACE(3, "slabAlloc({}, {})\n", bytes, index);
size_t nbytes = debugAddExtra(smartSizeClass(bytes));
assert(nbytes <= kSlabSize);
assert((nbytes & kSmartSizeAlignMask) == 0);
assert((uintptr_t(m_front) & kSmartSizeAlignMask) == 0);
if (UNLIKELY(m_bypassSlabAlloc)) {
// Stats correction; smartMallocSizeBig() pulls stats from jemalloc.
m_stats.usage -= bytes;
// smartMallocSizeBig already wraps its allocation in a debug header, but
// the caller will try to do it again, so we need to adjust this pointer
// before returning it.
return ((char*)smartMallocSizeBig<false>(nbytes).ptr) - kDebugExtraSize;
}
void* ptr = m_front;
{
void* next = (void*)(uintptr_t(ptr) + nbytes);
if (uintptr_t(next) <= uintptr_t(m_limit)) {
m_front = next;
} else {
ptr = newSlab(nbytes);
}
}
// Preallocate more of the same in order to amortize entry into this method.
unsigned nPrealloc;
if (nbytes * kSmartPreallocCountLimit <= kSmartPreallocBytesLimit) {
nPrealloc = kSmartPreallocCountLimit;
} else {
nPrealloc = kSmartPreallocBytesLimit / nbytes;
}
{
void* front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
if (uintptr_t(front) > uintptr_t(m_limit)) {
nPrealloc = ((uintptr_t)m_limit - uintptr_t(m_front)) / nbytes;
front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
}
m_front = front;
}
for (void* p = (void*)(uintptr_t(m_front) - nbytes); p != ptr;
p = (void*)(uintptr_t(p) - nbytes)) {
auto usable = debugRemoveExtra(nbytes);
auto ptr = debugPostAllocate(p, usable, usable);
debugPreFree(ptr, usable, usable);
m_freelists[index].push(ptr, usable);
}
return ptr;
}
/*
* Allocate `bytes' from the current slab, aligned to kSmallSizeAlign.
*/
inline void* MemoryManager::slabAlloc(uint32_t bytes, unsigned index) {
FTRACE(3, "slabAlloc({}, {}): m_front={}, m_limit={}\n", bytes, index,
m_front, m_limit);
uint32_t nbytes = smallIndex2Size(index);
assert(bytes <= nbytes);
assert(nbytes <= kSlabSize);
assert((nbytes & kSmallSizeAlignMask) == 0);
assert((uintptr_t(m_front) & kSmallSizeAlignMask) == 0);
if (UNLIKELY(m_bypassSlabAlloc)) {
// Stats correction; mallocBigSize() pulls stats from jemalloc.
m_stats.usage -= bytes;
return mallocBigSize<false>(nbytes).ptr;
}
void* ptr = m_front;
{
void* next = (void*)(uintptr_t(ptr) + nbytes);
if (uintptr_t(next) <= uintptr_t(m_limit)) {
m_front = next;
} else {
ptr = newSlab(nbytes);
}
}
// Preallocate more of the same in order to amortize entry into this method.
unsigned nPrealloc;
if (nbytes * kSmallPreallocCountLimit <= kSmallPreallocBytesLimit) {
nPrealloc = kSmallPreallocCountLimit;
} else {
nPrealloc = kSmallPreallocBytesLimit / nbytes;
}
{
void* front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
if (uintptr_t(front) > uintptr_t(m_limit)) {
nPrealloc = ((uintptr_t)m_limit - uintptr_t(m_front)) / nbytes;
front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
}
m_front = front;
}
for (void* p = (void*)(uintptr_t(m_front) - nbytes); p != ptr;
p = (void*)(uintptr_t(p) - nbytes)) {
m_freelists[index].push(p, nbytes);
}
FTRACE(4, "slabAlloc({}, {}) --> ptr={}, m_front={}, m_limit={}\n", bytes,
index, ptr, m_front, m_limit);
return ptr;
}
/*
* Allocate `bytes' from the current slab, aligned to kSmartSizeAlign.
*/
void* MemoryManager::slabAlloc(uint32_t bytes, unsigned index) {
size_t nbytes = debugAddExtra(smartSizeClass(bytes));
assert(nbytes <= kSlabSize);
assert((nbytes & kSmartSizeAlignMask) == 0);
assert((uintptr_t(m_front) & kSmartSizeAlignMask) == 0);
if (UNLIKELY(m_profctx.flag)) {
// Stats correction; smartMallocSizeBig() pulls stats from jemalloc.
m_stats.usage -= bytes;
return smartMallocSizeBig<false>(nbytes).first;
}
void* ptr = m_front;
{
void* next = (void*)(uintptr_t(ptr) + nbytes);
if (uintptr_t(next) <= uintptr_t(m_limit)) {
m_front = next;
} else {
ptr = newSlab(nbytes);
}
}
// Preallocate more of the same in order to amortize entry into this method.
unsigned nPrealloc;
if (nbytes * kSmartPreallocCountLimit <= kSmartPreallocBytesLimit) {
nPrealloc = kSmartPreallocCountLimit;
} else {
nPrealloc = kSmartPreallocBytesLimit / nbytes;
}
{
void* front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
if (uintptr_t(front) > uintptr_t(m_limit)) {
nPrealloc = ((uintptr_t)m_limit - uintptr_t(m_front)) / nbytes;
front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
}
m_front = front;
}
for (void* p = (void*)(uintptr_t(m_front) - nbytes); p != ptr;
p = (void*)(uintptr_t(p) - nbytes)) {
m_freelists[index].push(
debugPreFree(debugPostAllocate(p, debugRemoveExtra(nbytes),
debugRemoveExtra(nbytes)),
debugRemoveExtra(nbytes), debugRemoveExtra(nbytes)));
}
return ptr;
}
/*
* Allocate `bytes' from the current slab, aligned to kSmallSizeAlign.
*/
inline void* MemoryManager::slabAlloc(uint32_t bytes, unsigned index) {
FTRACE(3, "slabAlloc({}, {}): m_front={}, m_limit={}\n", bytes, index,
m_front, m_limit);
uint32_t nbytes = smallIndex2Size(index);
assert(bytes <= nbytes);
assert(nbytes <= kSlabSize);
assert((nbytes & kSmallSizeAlignMask) == 0);
assert((uintptr_t(m_front) & kSmallSizeAlignMask) == 0);
if (UNLIKELY(m_bypassSlabAlloc)) {
// Stats correction; mallocBigSize() pulls stats from jemalloc.
m_stats.usage -= bytes;
return mallocBigSize<false>(nbytes).ptr;
}
void* ptr = m_front;
{
void* next = (void*)(uintptr_t(ptr) + nbytes);
if (uintptr_t(next) <= uintptr_t(m_limit)) {
m_front = next;
} else {
ptr = newSlab(nbytes);
}
}
// Preallocate more of the same in order to amortize entry into this method.
unsigned nSplit = kNContigTab[index] - 1;
uintptr_t avail = uintptr_t(m_limit) - uintptr_t(m_front);
if (UNLIKELY(nSplit * nbytes > avail)) {
nSplit = avail / nbytes; // Expensive division.
}
if (nSplit > 0) {
void* tail = m_front;
uint32_t tailBytes = nSplit * nbytes;
m_front = (void*)(uintptr_t(m_front) + tailBytes);
splitTail(tail, tailBytes, nSplit, nbytes, index);
}
FTRACE(4, "slabAlloc({}, {}) --> ptr={}, m_front={}, m_limit={}\n", bytes,
index, ptr, m_front, m_limit);
return ptr;
}
// allocate nbytes from the current slab, aligned to kSmartSizeAlign
void* MemoryManager::slabAlloc(size_t nbytes, unsigned index) {
assert(nbytes <= kSlabSize);
assert((nbytes & kSmartSizeAlignMask) == 0);
assert((uintptr_t(m_front) & kSmartSizeAlignMask) == 0);
void* ptr = m_front;
{
void* next = (void*)(uintptr_t(ptr) + nbytes);
if (uintptr_t(next) <= uintptr_t(m_limit)) {
m_front = next;
} else {
ptr = newSlab(nbytes);
}
}
// Preallocate more of the same in order to amortize entry into this method.
unsigned nPrealloc;
if (nbytes * kSmartPreallocCountLimit <= kSmartPreallocBytesLimit) {
nPrealloc = kSmartPreallocCountLimit;
} else {
nPrealloc = kSmartPreallocBytesLimit / nbytes;
}
{
void* front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
if (uintptr_t(front) > uintptr_t(m_limit)) {
nPrealloc = ((uintptr_t)m_limit - uintptr_t(m_front)) / nbytes;
front = (void*)(uintptr_t(m_front) + nPrealloc*nbytes);
}
m_front = front;
}
for (void* p = (void*)(uintptr_t(m_front) - nbytes); p != ptr;
p = (void*)(uintptr_t(p) - nbytes)) {
m_freelists[index].push(
debugPreFree(debugPostAllocate(p, debugRemoveExtra(nbytes),
debugRemoveExtra(nbytes)),
debugRemoveExtra(nbytes), debugRemoveExtra(nbytes)));
}
return ptr;
}
