rt-thread/components/lwp/page.c

425 lines
8.9 KiB
C

/*
* Copyright (c) 2006-2019, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2019-11-01 Jesven The first version
*/
#include <stdint.h>
#include <rthw.h>
#include <rtthread.h>
#ifdef ARCH_MM_MMU
#include <page.h>
#include <mmu.h>
#define ARCH_PAGE_LIST_SIZE (ARCH_ADDRESS_WIDTH_BITS - ARCH_PAGE_SHIFT)
#define DBG_TAG "PAGE"
#define DBG_LVL DBG_WARNING
#include <rtdbg.h>
struct page
{
struct page *next; /* same level next */
struct page *pre; /* same level pre */
uint32_t size_bits; /* if is ARCH_ADDRESS_WIDTH_BITS, means not free */
int ref_cnt; /* page group ref count */
};
static struct page* page_start;
static void* page_addr;
static size_t page_nr;
static struct page *page_list[ARCH_PAGE_LIST_SIZE];
rt_weak int rt_hw_clz(size_t n)
{
int bits = sizeof(size_t) * 8;
n |= (n >> 1);
n |= (n >> 2);
n |= (n >> 4);
n |= (n >> 8);
n |= (n >> 16);
#ifdef ARCH_CPU_64BIT
n |= (n >> 32);
n = (n & 0x5555555555555555UL) + ((n >> 1) & 0x5555555555555555UL);
n = (n & 0x3333333333333333UL) + ((n >> 2) & 0x3333333333333333UL);
n = (n & 0x0707070707070707UL) + ((n >> 4) & 0x0707070707070707UL);
n = (n & 0x000f000f000f000fUL) + ((n >> 8) & 0x000f000f000f000fUL);
n = (n & 0x0000001f0000001fUL) + ((n >> 16) & 0x0000001f0000001fUL);
n = (n & 0x000000000000003fUL) + ((n >> 32) & 0x000000000000003fUL);
#else
n = (n & 0x55555555UL) + ((n >> 1) & 0x55555555UL);
n = (n & 0x33333333UL) + ((n >> 2) & 0x33333333UL);
n = (n & 0x07070707UL) + ((n >> 4) & 0x07070707UL);
n = (n & 0x000f000fUL) + ((n >> 8) & 0x000f000fUL);
n = (n & 0x0000001fUL) + ((n >> 16) & 0x0000001fUL);
#endif
return bits - n;
}
rt_weak int rt_hw_ctz(size_t n)
{
int ret = sizeof(size_t) * 8;
if (n)
{
ret -= (rt_hw_clz(n ^ (n - 1)) + 1);
}
return ret;
}
size_t rt_page_bits(size_t size)
{
int bit = sizeof(size_t) * 8 - rt_hw_clz(size) - 1;
if ((size ^ (1UL << bit)) != 0)
{
bit++;
}
bit -= ARCH_PAGE_SHIFT;
if (bit < 0)
{
bit = 0;
}
return bit;
}
static struct page * addr_to_page(void *addr)
{
size_t off;
if (addr < page_addr)
{
return 0;
}
off = (size_t)((char*)addr - (char*)page_addr);
off >>= ARCH_PAGE_SHIFT;
if (off >= page_nr)
{
return 0;
}
return &page_start[off];
}
static void* page_to_addr(struct page* p)
{
if (!p)
{
return 0;
}
return (void*)((char*)page_addr + ((p - page_start) << ARCH_PAGE_SHIFT));
}
static inline struct page *buddy_get(struct page *p, uint32_t size_bits)
{
size_t addr;
addr = (size_t)page_to_addr(p);
addr ^= (1UL << (size_bits + ARCH_PAGE_SHIFT));
return addr_to_page((void*)addr);
}
static void page_remove(struct page *p, uint32_t size_bits)
{
if (p->pre)
{
p->pre->next = p->next;
}
else
{
page_list[size_bits] = p->next;
}
if (p->next)
{
p->next->pre = p->pre;
}
p->size_bits = ARCH_ADDRESS_WIDTH_BITS;
}
static void page_insert(struct page *p, uint32_t size_bits)
{
p->next = page_list[size_bits];
if (p->next)
{
p->next->pre = p;
}
p->pre = 0;
page_list[size_bits] = p;
p->size_bits = size_bits;
}
static void _pages_ref_inc(struct page *p, uint32_t size_bits)
{
struct page *page_head;
int idx;
/* find page group head */
idx = p - page_start;
if (idx < 0 || idx >= page_nr)
{
return;
}
idx = idx & ~((1UL << size_bits) - 1);
page_head = page_start + idx;
page_head->ref_cnt++;
}
static int _pages_ref_get(struct page *p, uint32_t size_bits)
{
struct page *page_head;
int idx;
/* find page group head */
idx = p - page_start;
if (idx < 0 || idx >= page_nr)
{
return 0;
}
idx = idx & ~((1UL << size_bits) - 1);
page_head = page_start + idx;
return page_head->ref_cnt;
}
static int _pages_free(struct page *p, uint32_t size_bits)
{
uint32_t level = size_bits;
struct page *buddy;
RT_ASSERT(p->ref_cnt > 0);
RT_ASSERT(p->size_bits == ARCH_ADDRESS_WIDTH_BITS);
p->ref_cnt--;
if (p->ref_cnt != 0)
{
return 0;
}
while (level < ARCH_PAGE_LIST_SIZE)
{
buddy = buddy_get(p, level);
if (buddy && buddy->size_bits == level)
{
page_remove(buddy, level);
p = (p < buddy) ? p : buddy;
level++;
}
else
{
break;
}
}
page_insert(p, level);
return 1;
}
static struct page *_pages_alloc(uint32_t size_bits)
{
struct page *p;
if (page_list[size_bits])
{
p = page_list[size_bits];
page_remove(p, size_bits);
}
else
{
uint32_t level;
for (level = size_bits + 1; level < ARCH_PAGE_LIST_SIZE; level++)
{
if (page_list[level])
{
break;
}
}
if (level == ARCH_PAGE_LIST_SIZE)
{
return 0;
}
p = page_list[level];
page_remove(p, level);
while (level > size_bits)
{
page_insert(p, level - 1);
p = buddy_get(p, level - 1);
level--;
}
}
p->size_bits = ARCH_ADDRESS_WIDTH_BITS;
p->ref_cnt = 1;
return p;
}
int rt_page_ref_get(void *addr, uint32_t size_bits)
{
struct page *p;
rt_base_t level;
int ref;
p = addr_to_page(addr);
level = rt_hw_interrupt_disable();
ref = _pages_ref_get(p, size_bits);
rt_hw_interrupt_enable(level);
return ref;
}
void rt_page_ref_inc(void *addr, uint32_t size_bits)
{
struct page *p;
rt_base_t level;
p = addr_to_page(addr);
level = rt_hw_interrupt_disable();
_pages_ref_inc(p, size_bits);
rt_hw_interrupt_enable(level);
}
void *rt_pages_alloc(uint32_t size_bits)
{
struct page *p;
rt_base_t level;
level = rt_hw_interrupt_disable();
p = _pages_alloc(size_bits);
rt_hw_interrupt_enable(level);
return page_to_addr(p);
}
int rt_pages_free(void *addr, uint32_t size_bits)
{
struct page *p;
int real_free = 0;
p = addr_to_page(addr);
if (p)
{
rt_base_t level;
level = rt_hw_interrupt_disable();
real_free = _pages_free(p, size_bits);
rt_hw_interrupt_enable(level);
}
return real_free;
}
void list_page(void)
{
int i;
size_t total = 0;
rt_base_t level;
level = rt_hw_interrupt_disable();
for (i = 0; i < ARCH_PAGE_LIST_SIZE; i++)
{
struct page *p = page_list[i];
rt_kprintf("level %d ", i);
while (p)
{
total += (1UL << i);
rt_kprintf("[0x%08p]", page_to_addr(p));
p = p->next;
}
rt_kprintf("\n");
}
rt_hw_interrupt_enable(level);
rt_kprintf("free pages is %08x\n", total);
rt_kprintf("-------------------------------\n");
}
MSH_CMD_EXPORT(list_page, show page info);
void rt_page_get_info(size_t *total_nr, size_t *free_nr)
{
int i;
size_t total_free = 0;
rt_base_t level;
level = rt_hw_interrupt_disable();
for (i = 0; i < ARCH_PAGE_LIST_SIZE; i++)
{
struct page *p = page_list[i];
while (p)
{
total_free += (1UL << i);
p = p->next;
}
}
rt_hw_interrupt_enable(level);
*total_nr = page_nr;
*free_nr = total_free;
}
void rt_page_init(rt_region_t reg)
{
int i;
LOG_D("split 0x%08x 0x%08x\n", reg.start, reg.end);
reg.start += ARCH_PAGE_MASK;
reg.start &= ~ARCH_PAGE_MASK;
reg.end &= ~ARCH_PAGE_MASK;
{
int nr = ARCH_PAGE_SIZE / sizeof(struct page);
int total = (reg.end - reg.start) >> ARCH_PAGE_SHIFT;
int mnr = (total + nr) / (nr + 1);
LOG_D("nr = 0x%08x\n", nr);
LOG_D("total = 0x%08x\n", total);
LOG_D("mnr = 0x%08x\n", mnr);
RT_ASSERT(mnr < total);
page_start = (struct page*)reg.start;
reg.start += (mnr << ARCH_PAGE_SHIFT);
page_addr = (void*)reg.start;
page_nr = (reg.end - reg.start) >> ARCH_PAGE_SHIFT;
}
LOG_D("align 0x%08x 0x%08x\n", reg.start, reg.end);
/* init free list */
for (i = 0; i < ARCH_PAGE_LIST_SIZE; i++)
{
page_list[i] = 0;
}
/* add pages to free list */
while (reg.start != reg.end)
{
struct page *p;
int align_bits;
int size_bits;
size_bits = ARCH_ADDRESS_WIDTH_BITS - 1 - rt_hw_clz(reg.end - reg.start);
align_bits = rt_hw_ctz(reg.start);
if (align_bits < size_bits)
{
size_bits = align_bits;
}
p = addr_to_page((void*)reg.start);
p->size_bits = ARCH_ADDRESS_WIDTH_BITS;
p->ref_cnt = 1;
_pages_free(p, size_bits - ARCH_PAGE_SHIFT);
reg.start += (1UL << size_bits);
}
}
#endif