mirror of
https://github.com/DragonOS-Community/DragonOS.git
synced 2025-06-08 14:16:47 +00:00
🆕 kmalloc
This commit is contained in:
fslongjin
parent
1ad685f7a3
commit
828621dbbc
@ -68,7 +68,7 @@ void mm_init()
|
||||
memory_management_struct.bmp_len = (((unsigned long)(max_addr >> PAGE_2M_SHIFT) + sizeof(unsigned long) * 8 - 1) / 8) & (~(sizeof(unsigned long) - 1)); // bmp由多少个unsigned long变量组成
|
||||
|
||||
// 初始化bitmap， 先将整个bmp空间全部置位。稍后再将可用物理内存页复位。
|
||||
memset(memory_management_struct.bmp, 0xffffffffffffffff, memory_management_struct.bmp_len);
|
||||
memset(memory_management_struct.bmp, 0xff, memory_management_struct.bmp_len);
|
||||
|
||||
// 初始化内存页结构
|
||||
// 将页结构映射于bmp之后
|
||||
|
||||
193
kernel/mm/slab.c
193
kernel/mm/slab.c
@ -348,19 +348,13 @@ ul slab_init()
|
||||
// bmp后方预留4个unsigned long的空间防止内存越界,且按照8byte进行对齐
|
||||
memory_management_struct.end_of_struct += kmalloc_cache_group[i].cache_pool->bmp_len + ((sizeof(ul) << 2) & (~sizeof(ul) - 1));
|
||||
|
||||
memset(kmalloc_cache_group[i].cache_pool->bmp, 0, kmalloc_cache_group[i].cache_pool->bmp_len);
|
||||
// @todo：此处可优化，直接把所有位设置为0，然后再对部分不存在对应的内存对象的位设置为1
|
||||
memset(kmalloc_cache_group[i].cache_pool->bmp, 0xff, kmalloc_cache_group[i].cache_pool->bmp_len);
|
||||
for (int j = 0; j < kmalloc_cache_group[i].cache_pool->bmp_count; ++j)
|
||||
*(kmalloc_cache_group[i].cache_pool->bmp + (j >> 6)) ^= 1UL << (j % 64);
|
||||
|
||||
kmalloc_cache_group[i].count_total_using = 0;
|
||||
kmalloc_cache_group[i].count_total_free = kmalloc_cache_group[i].cache_pool->count_free;
|
||||
/*
|
||||
memset(kmalloc_cache_size[i].cache_pool->color_map,0xff,kmalloc_cache_size[i].cache_pool->color_length);
|
||||
|
||||
for(j = 0;j < kmalloc_cache_size[i].cache_pool->color_count;j++)
|
||||
*(kmalloc_cache_size[i].cache_pool->color_map + (j >> 6)) ^= 1UL << j % 64;
|
||||
|
||||
kmalloc_cache_size[i].total_free = kmalloc_cache_size[i].cache_pool->color_count;
|
||||
kmalloc_cache_size[i].total_using = 0;
|
||||
*/
|
||||
}
|
||||
|
||||
struct Page *page = NULL;
|
||||
@ -388,10 +382,10 @@ ul slab_init()
|
||||
for (int i = 0; i < 16; ++i)
|
||||
{
|
||||
// 获取一个新的空页并添加到空页表，然后返回其虚拟地址
|
||||
virt = (ul*)(PAGE_2M_ALIGN(memory_management_struct.end_of_struct+PAGE_2M_SIZE*i));
|
||||
virt = (ul *)(PAGE_2M_ALIGN(memory_management_struct.end_of_struct + PAGE_2M_SIZE * i));
|
||||
page = Virt_To_2M_Page(virt);
|
||||
|
||||
page_init(page, PAGE_PGT_MAPPED|PAGE_KERNEL|PAGE_KERNEL_INIT);
|
||||
page_init(page, PAGE_PGT_MAPPED | PAGE_KERNEL | PAGE_KERNEL_INIT);
|
||||
|
||||
kmalloc_cache_group[i].cache_pool->page = page;
|
||||
kmalloc_cache_group[i].cache_pool->vaddr = virt;
|
||||
@ -401,16 +395,187 @@ ul slab_init()
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief 在kmalloc中创建slab_obj的函数（与slab_malloc()中的类似)
|
||||
*
|
||||
* @param size
|
||||
* @return struct slab_obj* 创建好的slab_obj
|
||||
*/
|
||||
|
||||
struct slab_obj *kmalloc_create_slab_obj(ul size)
|
||||
{
|
||||
struct Page *page = alloc_pages(ZONE_NORMAL, 1, 0);
|
||||
|
||||
// BUG
|
||||
if (page == NULL)
|
||||
{
|
||||
kBUG("kmalloc_create()->alloc_pages()=>page == NULL");
|
||||
return NULL;
|
||||
}
|
||||
|
||||
page_init(page, PAGE_KERNEL);
|
||||
|
||||
ul *vaddr = NULL;
|
||||
ul struct_size = 0;
|
||||
struct slab_obj *slab_obj_ptr;
|
||||
|
||||
// 根据size大小，选择不同的分支来处理
|
||||
// 之所以选择512byte为分界点，是因为，此时bmp大小刚好为512byte。显而易见，选择过小的话会导致kmalloc函数与当前函数反复互相调用，最终导致栈溢出
|
||||
switch (size)
|
||||
{
|
||||
// ============ 对于size<=512byte的内存池对象，将slab_obj结构体和bmp放置在物理页的内部 ========
|
||||
// 由于这些对象的特征是，bmp占的空间大，而内存块的空间小，这样做的目的是避免再去申请一块内存来存储bmp，减少浪费。
|
||||
case 32:
|
||||
case 64:
|
||||
case 128:
|
||||
case 256:
|
||||
case 512:
|
||||
vaddr = phys_2_virt(page->addr_phys);
|
||||
// slab_obj结构体的大小 （本身的大小+bmp的大小）
|
||||
struct_size = sizeof(struct slab_obj) + PAGE_2M_SIZE / size / 8;
|
||||
// 将slab_obj放置到物理页的末尾
|
||||
slab_obj_ptr = (struct slab_obj *)((unsigned char *)vaddr + PAGE_2M_SIZE - struct_size);
|
||||
slab_obj_ptr->bmp = (ul *)slab_obj_ptr + sizeof(struct slab_obj);
|
||||
|
||||
slab_obj_ptr->count_free = (PAGE_2M_SIZE - struct_size) / size;
|
||||
slab_obj_ptr->count_using = 0;
|
||||
slab_obj_ptr->bmp_count = slab_obj_ptr->count_free;
|
||||
slab_obj_ptr->vaddr = vaddr;
|
||||
slab_obj_ptr->page = page;
|
||||
|
||||
list_init(&slab_obj_ptr->list);
|
||||
|
||||
slab_obj_ptr->bmp_len = ((slab_obj_ptr->bmp_count + sizeof(ul) * 8 - 1) >> 6) << 3;
|
||||
|
||||
// @todo：此处可优化，直接把所有位设置为0，然后再对部分不存在对应的内存对象的位设置为1
|
||||
memset(slab_obj_ptr->bmp, 0xff, slab_obj_ptr->bmp_len);
|
||||
|
||||
for (int i = 0; i < slab_obj_ptr->bmp_count; ++i)
|
||||
*(slab_obj_ptr->bmp + (i >> 6)) ^= 1UL << (i % 64);
|
||||
|
||||
break;
|
||||
// ================= 较大的size时，slab_obj和bmp不再放置于当前物理页内部 ============
|
||||
// 因为在这种情况下，bmp很短，继续放置在当前物理页内部则会造成可分配的对象少，加剧了内存空间的浪费
|
||||
case 1024: // 1KB
|
||||
case 2048:
|
||||
case 4096: // 4KB
|
||||
case 8192:
|
||||
case 16384:
|
||||
case 32768:
|
||||
case 65536:
|
||||
case 131072: // 128KB
|
||||
case 262144:
|
||||
case 524288:
|
||||
case 1048576: // 1MB
|
||||
slab_obj_ptr = (struct Slab *)kmalloc(sizeof(struct slab_obj), 0);
|
||||
|
||||
slab_obj_ptr->count_free = PAGE_2M_SIZE / size;
|
||||
slab_obj_ptr->count_using = 0;
|
||||
slab_obj_ptr->bmp_count = slab_obj_ptr->count_free;
|
||||
|
||||
slab_obj_ptr->bmp_len = ((slab_obj_ptr->bmp_count + sizeof(ul) * 8 - 1) >> 6) << 3;
|
||||
|
||||
slab_obj_ptr->bmp = (ul *)kmalloc(slab_obj_ptr->bmp_len, 0);
|
||||
|
||||
// @todo：此处可优化，直接把所有位设置为0，然后再对部分不存在对应的内存对象的位设置为1
|
||||
memset(slab_obj_ptr->bmp, 0xff, slab_obj_ptr->bmp_len);
|
||||
for (int i = 0; i < slab_obj_ptr->bmp_count; ++i)
|
||||
*(slab_obj_ptr->bmp + (i >> 6)) ^= 1UL << (i % 64);
|
||||
|
||||
slab_obj_ptr->vaddr = phys_2_virt(page->addr_phys);
|
||||
slab_obj_ptr->page = page;
|
||||
list_init(&slab_obj_ptr->list);
|
||||
break;
|
||||
// size 错误
|
||||
default:
|
||||
kerror("kamlloc_create(): Wrong size%d\n", size);
|
||||
free_pages(page, 1);
|
||||
return NULL;
|
||||
break;
|
||||
}
|
||||
|
||||
return slab_obj_ptr;
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief 通用内存分配函数
|
||||
*
|
||||
* @param size 要分配的内存大小
|
||||
* @param flags 内存的flag
|
||||
* @return void*
|
||||
* @return void* 内核内存虚拟地址
|
||||
*/
|
||||
void *kmalloc(unsigned long size, unsigned long flags)
|
||||
{
|
||||
// @todo: 内存分配函数
|
||||
if (size > 1048576)
|
||||
{
|
||||
kwarn("kmalloc(): Can't alloc such memory: %ld bytes, because it is too large.", size);
|
||||
return NULL;
|
||||
}
|
||||
int index;
|
||||
for (int i = 0; i < 16; ++i)
|
||||
if (kmalloc_cache_group[i].size >= size)
|
||||
{
|
||||
index = i;
|
||||
break;
|
||||
}
|
||||
|
||||
struct slab_obj *slab_obj_ptr = kmalloc_cache_group[index].cache_pool;
|
||||
|
||||
// 内存池没有可用的内存对象，需要进行扩容
|
||||
if (kmalloc_cache_group[index].count_total_free == 0)
|
||||
{
|
||||
// 创建slab_obj
|
||||
slab_obj_ptr = kmalloc_create_slab_obj(kmalloc_cache_group[index].size);
|
||||
|
||||
// BUG
|
||||
if (slab_obj_ptr == NULL)
|
||||
{
|
||||
kBUG("kmalloc()->kmalloc_create_slab_obj()=>slab == NULL");
|
||||
return NULL;
|
||||
}
|
||||
|
||||
kmalloc_cache_group[index].count_total_free += slab_obj_ptr->count_free;
|
||||
list_add(&kmalloc_cache_group[index].cache_pool->list, &slab_obj_ptr->list);
|
||||
}
|
||||
else // 内存对象充足
|
||||
{
|
||||
do
|
||||
{
|
||||
// 跳转到下一个内存池对象
|
||||
if (slab_obj_ptr->count_free == 0)
|
||||
slab_obj_ptr = container_of(list_next(&slab_obj_ptr->list), struct slab_obj, list);
|
||||
else
|
||||
break;
|
||||
} while (slab_obj_ptr != kmalloc_cache_group[index].cache_pool);
|
||||
}
|
||||
|
||||
// 寻找一块可用的内存对象
|
||||
int md;
|
||||
for (int i = 0; i < slab_obj_ptr->count_free; ++i)
|
||||
{
|
||||
// 当前bmp全部被使用
|
||||
if (*slab_obj_ptr->bmp + (i >> 6) == 0xffffffffffffffffUL)
|
||||
{
|
||||
i += 63;
|
||||
continue;
|
||||
}
|
||||
md = i % 64;
|
||||
// 找到相应的内存对象
|
||||
if (*(slab_obj_ptr->bmp + (i >> 6)) & (1UL << md) == 0)
|
||||
{
|
||||
*(slab_obj_ptr->bmp + (i >> 6)) |= (1UL << md);
|
||||
++(slab_obj_ptr->count_using);
|
||||
--(slab_obj_ptr->count_free);
|
||||
|
||||
--kmalloc_cache_group[index].count_total_free;
|
||||
++kmalloc_cache_group[index].count_total_using;
|
||||
|
||||
return (void*)((char*)slab_obj_ptr->vaddr+kmalloc_cache_group[index].size*i);
|
||||
}
|
||||
}
|
||||
|
||||
kerror("kmalloc(): Cannot alloc more memory: %d bytes", size);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
|
||||
@ -102,6 +102,15 @@ void *slab_malloc(struct slab *slab_pool, ul arg);
|
||||
*/
|
||||
ul slab_free(struct slab *slab_pool, void *addr, ul arg);
|
||||
|
||||
/**
|
||||
* @brief 在kmalloc中创建slab_obj的函数（与slab_malloc()类似)
|
||||
*
|
||||
* @param size
|
||||
* @return struct slab_obj* 创建好的slab_obj
|
||||
*/
|
||||
struct slab_obj * kmalloc_create_slab_obj(ul size);
|
||||
|
||||
|
||||
/**
|
||||
* @brief 初始化内存池组
|
||||
* 在初始化通用内存管理单元期间，尚无内存空间分配函数，需要我们手动为SLAB内存池指定存储空间
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user