Fix allocate and free
This commit is contained in:
parent
f278777c0e
commit
f49a98ab54
198
GL/alloc/alloc.c
198
GL/alloc/alloc.c
|
@ -1,4 +1,6 @@
|
|||
#include <stdint.h>
|
||||
#include <string.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#include "alloc.h"
|
||||
|
||||
|
@ -35,6 +37,10 @@
|
|||
*
|
||||
* We could go down to 128 bytes if wastage is an issue, but then we have
|
||||
* to store double the number of usage markers.
|
||||
*
|
||||
* FIXME:
|
||||
*
|
||||
* - Allocations < 2048 can still cross boundaries
|
||||
*/
|
||||
|
||||
#include <assert.h>
|
||||
|
@ -69,7 +75,12 @@ typedef struct {
|
|||
size_t block_count; // Number of 2k blocks in the pool
|
||||
|
||||
/* It's frustrating that we need to do this dynamically
|
||||
* but we need to know the size allocated when we free() */
|
||||
* but we need to know the size allocated when we free()...
|
||||
* we could store it statically but it would take 64k if we had
|
||||
* an array of block_index -> block size where there would be 2 ** 32
|
||||
* entries of 16 bit block sizes. The drawback (aside the memory usage)
|
||||
* would be that we won't be able to order by size, so defragging will
|
||||
* take much more time.*/
|
||||
struct AllocEntry* allocations;
|
||||
} PoolHeader;
|
||||
|
||||
|
@ -79,10 +90,12 @@ static PoolHeader pool_header = {
|
|||
};
|
||||
|
||||
void* alloc_base_address(void* pool) {
|
||||
(void) pool;
|
||||
return pool_header.base_address;
|
||||
}
|
||||
|
||||
size_t alloc_block_count(void* pool) {
|
||||
(void) pool;
|
||||
return pool_header.block_count;
|
||||
}
|
||||
|
||||
|
@ -91,7 +104,9 @@ void* alloc_next_available(void* pool, size_t required_size) {
|
|||
uint32_t required_subblocks = (required_size / 256);
|
||||
if(required_size % 256) required_subblocks += 1;
|
||||
|
||||
while(true) {
|
||||
uint8_t* end = pool_header.block_usage + pool_header.block_count;
|
||||
|
||||
while(it < end) {
|
||||
// Skip full blocks
|
||||
while((*it) == 255) {
|
||||
++it;
|
||||
|
@ -102,6 +117,8 @@ void* alloc_next_available(void* pool, size_t required_size) {
|
|||
}
|
||||
|
||||
uint32_t found_subblocks = 0;
|
||||
|
||||
/* Anything gte to 2048 must be aligned to a 2048 boundary */
|
||||
bool requires_alignment = required_size >= 2048;
|
||||
|
||||
/* We just need to find enough consecutive blocks */
|
||||
|
@ -112,6 +129,11 @@ void* alloc_next_available(void* pool, size_t required_size) {
|
|||
if(t == 255) {
|
||||
++it;
|
||||
found_subblocks = 0;
|
||||
|
||||
if(it >= end) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
continue;
|
||||
}
|
||||
|
||||
|
@ -140,20 +162,19 @@ void* alloc_next_available(void* pool, size_t required_size) {
|
|||
}
|
||||
|
||||
++it;
|
||||
if(it >= pool_header.block_usage + sizeof(pool_header.block_usage)) {
|
||||
if(it >= end) {
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
uint32_t alloc_block_from_address(void* p) {
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
int alloc_init(void* pool, size_t size) {
|
||||
(void) pool;
|
||||
|
||||
if(pool_header.pool) {
|
||||
return -1;
|
||||
}
|
||||
|
@ -167,48 +188,169 @@ int alloc_init(void* pool, size_t size) {
|
|||
memset(pool_header.block_usage, 0, sizeof(pool_header.block_usage));
|
||||
pool_header.pool = pool;
|
||||
pool_header.pool_size = size;
|
||||
pool_header.base_address = round_up(pool_header.pool, 2048);
|
||||
pool_header.base_address = (uint8_t*) round_up((uintptr_t) pool_header.pool, 2048);
|
||||
pool_header.block_count = ((p + size) - pool_header.base_address) / 2048;
|
||||
pool_header.allocations = NULL;
|
||||
|
||||
assert(((uintptr_t) pool_header.base_address) % 2048 == 0);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void alloc_shutdown(void* pool) {
|
||||
pool_header.pool = NULL;
|
||||
(void) pool;
|
||||
|
||||
struct AllocEntry* it = pool_header.allocations;
|
||||
while(it) {
|
||||
struct AllocEntry* next = it->next;
|
||||
free(it);
|
||||
it = next;
|
||||
}
|
||||
|
||||
memset(&pool_header, 0, sizeof(pool_header));
|
||||
}
|
||||
|
||||
static inline uint32_t size_to_subblock_count(size_t size) {
|
||||
uint32_t required_subblocks = (size / 256);
|
||||
if(size % 256) required_subblocks += 1;
|
||||
return required_subblocks;
|
||||
}
|
||||
|
||||
static inline uint32_t subblock_from_pointer(void* p) {
|
||||
uint8_t* ptr = (uint8_t*) p;
|
||||
return (ptr - pool_header.base_address) / 256;
|
||||
}
|
||||
|
||||
void* alloc_malloc(void* pool, size_t size) {
|
||||
void* ret = alloc_next_available(pool, size);
|
||||
if(size >= 2048) {
|
||||
assert(((uintptr_t) ret) % 2048 == 0);
|
||||
}
|
||||
|
||||
if(ret) {
|
||||
uintptr_t start_subblock = (uint8_t*) ret - pool_header.base_address;
|
||||
|
||||
uint32_t required_subblocks = (size / 256);
|
||||
if(size % 256) required_subblocks += 1;
|
||||
|
||||
uintptr_t start_block = start_subblock / 8;
|
||||
uintptr_t filled_blocks = required_subblocks / 8;
|
||||
uintptr_t trailing_subblocks = required_subblocks % 8;
|
||||
|
||||
for(size_t i = start_block; i < start_block + filled_blocks; ++i) {
|
||||
pool_header.block_usage[i] = 255;
|
||||
}
|
||||
|
||||
uint8_t* trailing = &pool_header.block_usage[start_block + filled_blocks];
|
||||
uintptr_t start_subblock = subblock_from_pointer(ret);
|
||||
uint32_t required_subblocks = size_to_subblock_count(size);
|
||||
size_t offset = start_subblock % 8;
|
||||
size_t block = start_subblock / 8;
|
||||
uint8_t mask = 0;
|
||||
for(size_t i = 0; i < trailing_subblocks; ++i) {
|
||||
mask |= 1;
|
||||
mask <<= 1;
|
||||
|
||||
/* Toggle any bits for the first block */
|
||||
for(int i = offset - 1; i >= 0; --i) {
|
||||
mask |= (1 << i);
|
||||
required_subblocks--;
|
||||
}
|
||||
|
||||
mask <<= 8 - trailing_subblocks - 1;
|
||||
*trailing |= mask;
|
||||
if(mask) {
|
||||
pool_header.block_usage[block++] |= mask;
|
||||
}
|
||||
|
||||
/* Fill any full blocks in the middle of the allocation */
|
||||
while(required_subblocks > 8) {
|
||||
pool_header.block_usage[block++] = 255;
|
||||
required_subblocks -= 8;
|
||||
}
|
||||
|
||||
/* Fill out any trailing subblocks */
|
||||
mask = 0;
|
||||
for(size_t i = 0; i < required_subblocks; ++i) {
|
||||
mask |= (1 << (7 - i));
|
||||
}
|
||||
|
||||
if(mask) {
|
||||
pool_header.block_usage[block++] |= mask;
|
||||
}
|
||||
|
||||
|
||||
/* Insert allocations in the list by size descending so that when we
|
||||
* defrag we can move the larger blocks before the smaller ones without
|
||||
* much effort */
|
||||
struct AllocEntry* new_entry = (struct AllocEntry*) malloc(sizeof(struct AllocEntry));
|
||||
new_entry->pointer = ret;
|
||||
new_entry->size = size;
|
||||
new_entry->next = NULL;
|
||||
|
||||
struct AllocEntry* it = pool_header.allocations;
|
||||
struct AllocEntry* last = NULL;
|
||||
|
||||
if(!it) {
|
||||
pool_header.allocations = new_entry;
|
||||
} else {
|
||||
while(it) {
|
||||
if(it->size < size) {
|
||||
if(last) {
|
||||
last->next = new_entry;
|
||||
} else {
|
||||
pool_header.allocations = new_entry;
|
||||
}
|
||||
|
||||
new_entry->next = it;
|
||||
break;
|
||||
} else if(!it->next) {
|
||||
it->next = new_entry;
|
||||
new_entry->next = NULL;
|
||||
break;
|
||||
}
|
||||
|
||||
last = it;
|
||||
it = it->next;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
void alloc_free(void* pool, void* p) {
|
||||
struct AllocEntry* it = pool_header.allocations;
|
||||
struct AllocEntry* last = NULL;
|
||||
while(it) {
|
||||
if(it->pointer == p) {
|
||||
size_t used_subblocks = size_to_subblock_count(it->size);
|
||||
size_t subblock = subblock_from_pointer(p);
|
||||
size_t block = subblock / 8;
|
||||
size_t offset = subblock % 8;
|
||||
uint8_t mask = 0;
|
||||
|
||||
/* Wipe out any leading subblocks */
|
||||
for(int i = offset; i > 0; --i) {
|
||||
mask |= (1 << i);
|
||||
used_subblocks--;
|
||||
}
|
||||
|
||||
if(mask) {
|
||||
pool_header.block_usage[block++] &= ~mask;
|
||||
}
|
||||
|
||||
/* Clear any full blocks in the middle of the allocation */
|
||||
while(used_subblocks > 8) {
|
||||
pool_header.block_usage[block++] = 0;
|
||||
used_subblocks -= 8;
|
||||
}
|
||||
|
||||
/* Wipe out any trailing subblocks */
|
||||
mask = 0;
|
||||
for(size_t i = 0; i < used_subblocks; ++i) {
|
||||
mask |= (1 << (7 - i));
|
||||
}
|
||||
|
||||
if(mask) {
|
||||
pool_header.block_usage[block++] &= ~mask;
|
||||
}
|
||||
|
||||
if(last) {
|
||||
last->next = it->next;
|
||||
} else {
|
||||
assert(it == pool_header.allocations);
|
||||
pool_header.allocations = it->next;
|
||||
}
|
||||
|
||||
free(it);
|
||||
break;
|
||||
}
|
||||
|
||||
last = it;
|
||||
it = it->next;
|
||||
}
|
||||
}
|
||||
|
||||
void alloc_defrag_start(void* pool) {
|
||||
|
|
Loading…
Reference in New Issue
Block a user