sandbox: vm: reduce vm_page order field size to 4 bits

This commit is contained in:
2023-02-02 16:54:48 +00:00
parent ab46b7cd13
commit 7331bdefda
2 changed files with 26 additions and 7 deletions

View File

@@ -60,9 +60,15 @@ typedef enum vm_page_order {
VM_PAGE_32M,
VM_PAGE_64M,
VM_PAGE_128M,
#if 0
/* vm_page_t only has 4 bits to store the page order with.
the maximum order that can be stored in 4 bits is 15 (VM_PAGE_128M)
to use any of the page orders listed here, this field
will have to be expanded. */
VM_PAGE_256M,
VM_PAGE_512M,
VM_PAGE_1G,
#endif
VM_PAGE_MIN_ORDER = VM_PAGE_4K,
VM_PAGE_MAX_ORDER = VM_PAGE_8M,
} vm_page_order_t;
@@ -110,18 +116,25 @@ typedef enum vm_page_flags {
} vm_page_flags_t;
typedef struct vm_page {
/* order of the page block that this page belongs too */
uint16_t p_order : 4;
/* the id of the NUMA node that this page belongs to */
uint32_t p_node : 6;
uint16_t p_node : 6;
/* the id of the memory zone that this page belongs to */
uint32_t p_zone : 2;
/* vm_page_flags_t bitfields. */
uint32_t p_flags : 24;
uint16_t p_zone : 3;
/* some unused bits */
uint16_t p_reserved : 3;
/* buddy allocator free page list head (vm_zone_t->z_free_pages[p_order]) */
/* vm_page_flags_t bitfields. */
uint32_t p_flags;
/* multi-purpose list.
the owner of the page can decide what to do with this.
some examples:
- the buddy allocator uses this to maintain its per-zone free-page lists.
*/
queue_entry_t p_free_list;
/* order of the page block that this page belongs too */
unsigned char p_order;
} __attribute__((aligned(2 * sizeof(unsigned long)))) vm_page_t;
extern kern_status_t vm_bootstrap(const vm_zone_descriptor_t *zones, size_t nr_zones);

View File

@@ -28,9 +28,15 @@ static size_t page_order_bytes[] = {
[VM_PAGE_32M] = 0x2000000,
[VM_PAGE_64M] = 0x4000000,
[VM_PAGE_128M] = 0x8000000,
#if 0
/* vm can support pages of this size, but
vm_page_t only has 4 bits with which to store
the page order, which cannot accomodate these
larger order numbers */
[VM_PAGE_256M] = 0x10000000,
[VM_PAGE_512M] = 0x20000000,
[VM_PAGE_1G] = 0x40000000,
#endif
};
void vm_page_init_array()