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VM: static data structure for mem allocation

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. allocate physical memory using a fixed, pre-allocated bitmap so there
   are no call cycles and it's avilable earlier
This commit is contained in:
Ben Gras 2012-09-18 13:17:48 +02:00
parent 2cb560297c
commit 6d7b770761
10 changed files with 110 additions and 228 deletions
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2
servers/vm/Makefile
View file

@ -3,7 +3,7 @@
PROG= vm
SRCS= main.c alloc.c utility.c exit.c fork.c break.c \
mmap.c slaballoc.c region.c pagefaults.c addravl.c \
mmap.c slaballoc.c region.c pagefaults.c \
physravl.c rs.c queryexit.c yieldedavl.c regionavl.c
DPADD+= ${LIBSYS}

8
servers/vm/addravl.c
View file

@ -1,8 +0,0 @@
#include "proto.h"
#include "sanitycheck.h"
#include "pagerange.h"
#include "addravl_defs.h"
#include "cavl_if.h"
#include "cavl_impl.h"

9
servers/vm/addravl.h
View file

@ -1,9 +0,0 @@
#ifndef ADDRAVL
#define ADDRAVL 1
#include "addravl_defs.h"
#include "cavl_if.h"
#include "unavl.h"
#endif

17
servers/vm/addravl_defs.h
View file

@ -1,17 +0,0 @@
#define AVL_UNIQUE(id) addr_ ## id
#define AVL_HANDLE pagerange_t *
#define AVL_KEY phys_bytes
#define AVL_MAX_DEPTH 30 /* good for 2 million nodes */
#define AVL_NULL NULL
#define AVL_GET_LESS(h, a) (h)->less
#define AVL_GET_GREATER(h, a) (h)->greater
#define AVL_SET_LESS(h1, h2) USE((h1), (h1)->less = h2;);
#define AVL_SET_GREATER(h1, h2) USE((h1), (h1)->greater = h2;);
#define AVL_GET_BALANCE_FACTOR(h) (h)->factor
#define AVL_SET_BALANCE_FACTOR(h, f) USE((h), (h)->factor = f;);
#define AVL_SET_ROOT(h, v) (h)->root = v;
#define AVL_COMPARE_KEY_KEY(k1, k2) ((k1) > (k2) ? 1 : ((k1) < (k2) ? -1 : 0))
#define AVL_COMPARE_KEY_NODE(k, h) AVL_COMPARE_KEY_KEY((k), (h)->addr)
#define AVL_COMPARE_NODE_NODE(h1, h2) AVL_COMPARE_KEY_KEY((h1)->addr, (h2)->addr)
#define AVL_INSIDE_STRUCT char pad[4];

260
servers/vm/alloc.c
View file

@ -26,13 +26,16 @@
#include "proto.h"
#include "util.h"
#include "glo.h"
#include "pagerange.h"
#include "addravl.h"
#include "sanitycheck.h"
#include "memlist.h"
/* AVL tree of free pages. */
addr_avl addravl;
/* Number of physical pages in a 32-bit address space */
#define NUMBER_PHYSICAL_PAGES (0x100000000ULL/VM_PAGE_SIZE)
#define PAGE_BITMAP_CHUNKS BITMAP_CHUNKS(NUMBER_PHYSICAL_PAGES)
static bitchunk_t free_pages_bitmap[PAGE_BITMAP_CHUNKS];
#define PAGE_CACHE_MAX 10000
static int free_page_cache[PAGE_CACHE_MAX];
static int free_page_cache_size = 0;
/* Used for sanity check. */
static phys_bytes mem_low, mem_high;
@ -47,6 +50,8 @@ static phys_bytes alloc_pages(int pages, int flags, phys_bytes *ret);
static bitchunk_t pagemap[CHUNKS];
#endif
#define page_isfree(i) GET_BIT(free_pages_bitmap, i)
/*===========================================================================*
* alloc_mem *
*===========================================================================*/
@ -125,10 +130,10 @@ struct memory *chunks; /* list of free memory chunks */
*/
int i, first = 0;
addr_init(&addravl);
total_pages = 0;
memset(free_pages_bitmap, 0, sizeof(free_pages_bitmap));
/* Use the chunks of physical memory to allocate holes. */
for (i=NR_MEMS-1; i>=0; i--) {
if (chunks[i].size > 0) {
@ -146,40 +151,64 @@ struct memory *chunks; /* list of free memory chunks */
#if SANITYCHECKS
void mem_sanitycheck(char *file, int line)
{
pagerange_t *p, *prevp = NULL;
addr_iter iter;
addr_start_iter_least(&addravl, &iter);
while((p=addr_get_iter(&iter))) {
SLABSANE(p);
assert(p->size > 0);
if(prevp) {
assert(prevp->addr < p->addr);
assert(prevp->addr + prevp->size < p->addr);
}
usedpages_add(p->addr * VM_PAGE_SIZE, p->size * VM_PAGE_SIZE);
prevp = p;
addr_incr_iter(&iter);
int i;
for(i = 0; i < NUMBER_PHYSICAL_PAGES; i++) {
if(!page_isfree(i)) continue;
usedpages_add(i * VM_PAGE_SIZE, VM_PAGE_SIZE);
}
}
#endif
void memstats(int *nodes, int *pages, int *largest)
{
pagerange_t *p;
addr_iter iter;
addr_start_iter_least(&addravl, &iter);
int i;
*nodes = 0;
*pages = 0;
*largest = 0;
while((p=addr_get_iter(&iter))) {
SLABSANE(p);
(*nodes)++;
(*pages)+= p->size;
if(p->size > *largest)
*largest = p->size;
addr_incr_iter(&iter);
for(i = 0; i < NUMBER_PHYSICAL_PAGES; i++) {
int size = 0;
while(i < NUMBER_PHYSICAL_PAGES && page_isfree(i)) {
size++;
i++;
}
if(size == 0) continue;
(*nodes)++;
(*pages)+= size;
if(size > *largest)
*largest = size;
}
}
static int findbit(int low, int startscan, int pages, int memflags, int *len)
{
int run_length = 0, i, freerange_start;
for(i = startscan; i >= low; i--) {
if(!page_isfree(i)) {
int pi;
int chunk = i/BITCHUNK_BITS, moved = 0;
run_length = 0;
pi = i;
while(chunk > 0 &&
!MAP_CHUNK(free_pages_bitmap, chunk*BITCHUNK_BITS)) {
chunk--;
moved = 1;
}
if(moved) { i = chunk * BITCHUNK_BITS + BITCHUNK_BITS; }
continue;
}
if(!run_length) { freerange_start = i; run_length = 1; }
else { freerange_start--; run_length++; }
assert(run_length <= pages);
if(run_length == pages || (memflags & PAF_FIRSTBLOCK)) {
/* good block found! */
*len = run_length;
return freerange_start;
}
}
return NO_MEM;
}
/*===========================================================================*
@ -187,16 +216,12 @@ void memstats(int *nodes, int *pages, int *largest)
*===========================================================================*/
static phys_bytes alloc_pages(int pages, int memflags, phys_bytes *len)
{
addr_iter iter;
pagerange_t *pr;
int incr;
phys_bytes boundary16 = 16 * 1024 * 1024 / VM_PAGE_SIZE;
phys_bytes boundary1 = 1 * 1024 * 1024 / VM_PAGE_SIZE;
phys_bytes mem;
#if SANITYCHECKS
int firstnodes, firstpages, wantnodes, wantpages;
int finalnodes, finalpages;
int largest;
phys_bytes mem = NO_MEM;
int maxpage = NUMBER_PHYSICAL_PAGES - 1, i;
static int lastscan = -1;
int startscan, run_length;
#if NONCONTIGUOUS
/* If NONCONTIGUOUS is on, allocate physical pages single
@ -209,84 +234,60 @@ static phys_bytes alloc_pages(int pages, int memflags, phys_bytes *len)
}
#endif
memstats(&firstnodes, &firstpages, &largest);
wantnodes = firstnodes;
wantpages = firstpages - pages;
#endif
if(memflags & (PAF_LOWER16MB|PAF_LOWER1MB)) {
addr_start_iter_least(&addravl, &iter);
incr = 1;
} else {
addr_start_iter_greatest(&addravl, &iter);
incr = 0;
}
while((pr = addr_get_iter(&iter))) {
SLABSANE(pr);
assert(pr->size > 0);
if(pr->size >= pages || (memflags & PAF_FIRSTBLOCK)) {
if(memflags & PAF_LOWER16MB) {
if(pr->addr + pages > boundary16)
return NO_MEM;
}
if(memflags & PAF_LOWER1MB) {
if(pr->addr + pages > boundary1)
return NO_MEM;
}
/* good block found! */
if(memflags & PAF_LOWER16MB)
maxpage = boundary16 - 1;
else if(memflags & PAF_LOWER1MB)
maxpage = boundary1 - 1;
else {
/* no position restrictions: check page cache */
if((pages == 1 || (memflags & PAF_FIRSTBLOCK))) {
while(free_page_cache_size > 0) {
i = free_page_cache[free_page_cache_size-1];
if(page_isfree(i)) {
free_page_cache_size--;
mem = i;
assert(mem != NO_MEM);
run_length = 1;
break;
}
if(incr)
addr_incr_iter(&iter);
else
addr_decr_iter(&iter);
free_page_cache_size--;
}
}
}
if(!pr) {
if(lastscan < maxpage && lastscan >= 0)
startscan = lastscan;
else startscan = maxpage;
if(mem == NO_MEM)
mem = findbit(0, startscan, pages, memflags, &run_length);
if(mem == NO_MEM)
mem = findbit(0, maxpage, pages, memflags, &run_length);
if(mem == NO_MEM) {
if(len)
*len = 0;
#if SANITYCHECKS
assert(largest < pages);
#endif
return NO_MEM;
}
SLABSANE(pr);
/* remember for next time */
lastscan = mem;
if(memflags & PAF_FIRSTBLOCK) {
assert(len);
/* block doesn't have to as big as requested;
* return its size though.
*/
if(pr->size < pages) {
pages = pr->size;
#if SANITYCHECKS
wantpages = firstpages - pages;
#endif
if(run_length < pages) {
pages = run_length;
}
}
if(len)
*len = pages;
/* Allocated chunk is off the end. */
mem = pr->addr + pr->size - pages;
assert(pr->size >= pages);
if(pr->size == pages) {
pagerange_t *prr;
prr = addr_remove(&addravl, pr->addr);
assert(prr);
assert(prr == pr);
SLABFREE(pr);
#if SANITYCHECKS
wantnodes--;
#endif
} else {
USE(pr, pr->size -= pages;);
for(i = mem; i < mem + pages; i++) {
UNSET_BIT(free_pages_bitmap, i);
}
if(memflags & PAF_CLEAR) {
@ -296,13 +297,6 @@ static phys_bytes alloc_pages(int pages, int memflags, phys_bytes *len)
panic("alloc_mem: sys_memset failed: %d", s);
}
#if SANITYCHECKS
memstats(&finalnodes, &finalpages, &largest);
assert(finalnodes == wantnodes);
assert(finalpages == wantpages);
#endif
return mem;
}
@ -311,19 +305,7 @@ static phys_bytes alloc_pages(int pages, int memflags, phys_bytes *len)
*===========================================================================*/
static void free_pages(phys_bytes pageno, int npages)
{
pagerange_t *pr, *p;
addr_iter iter;
#if SANITYCHECKS
int firstnodes, firstpages, wantnodes, wantpages;
int finalnodes, finalpages, largest;
memstats(&firstnodes, &firstpages, &largest);
wantnodes = firstnodes;
wantpages = firstpages + npages;
#endif
assert(!addr_search(&addravl, pageno, AVL_EQUAL));
int i, lim = pageno + npages - 1;
#if JUNKFREE
if(sys_memset(NONE, 0xa5a5a5a5, VM_PAGE_SIZE * pageno,
@ -331,54 +313,12 @@ static void free_pages(phys_bytes pageno, int npages)
panic("free_pages: sys_memset failed");
#endif
/* try to merge with higher neighbour */
if((pr=addr_search(&addravl, pageno+npages, AVL_EQUAL))) {
USE(pr, pr->addr -= npages;
pr->size += npages;);
} else {
if(!SLABALLOC(pr))
panic("alloc_pages: can't alloc");
#if SANITYCHECKS
memstats(&firstnodes, &firstpages, &largest);
wantnodes = firstnodes;
wantpages = firstpages + npages;
#endif
assert(npages > 0);
USE(pr, pr->addr = pageno;
pr->size = npages;);
addr_insert(&addravl, pr);
#if SANITYCHECKS
wantnodes++;
#endif
}
addr_start_iter(&addravl, &iter, pr->addr, AVL_EQUAL);
p = addr_get_iter(&iter);
assert(p);
assert(p == pr);
addr_decr_iter(&iter);
if((p = addr_get_iter(&iter))) {
SLABSANE(p);
if(p->addr + p->size == pr->addr) {
USE(p, p->size += pr->size;);
addr_remove(&addravl, pr->addr);
SLABFREE(pr);
#if SANITYCHECKS
wantnodes--;
#endif
for(i = pageno; i <= lim; i++) {
SET_BIT(free_pages_bitmap, i);
if(free_page_cache_size < PAGE_CACHE_MAX) {
free_page_cache[free_page_cache_size++] = i;
}
}
#if SANITYCHECKS
memstats(&finalnodes, &finalpages, &largest);
assert(finalnodes == wantnodes);
assert(finalpages == wantpages);
#endif
}
/*===========================================================================*

6
servers/vm/arch/i386/pagetable.c
View file

@ -259,6 +259,8 @@ static void *vm_checkspares(void)
return NULL;
}
static int pt_init_done;
/*===========================================================================*
* vm_allocpage *
*===========================================================================*/
@ -280,7 +282,7 @@ void *vm_allocpage(phys_bytes *phys, int reason)
assert(level >= 1);
assert(level <= 2);
if(level > 1 || !meminit_done) {
if((level > 1) || !pt_init_done) {
void *s;
s=vm_getsparepage(phys);
level--;
@ -1021,6 +1023,8 @@ void pt_init(void)
assert(vmproc[VM_PROC_NR].vm_endpoint == VM_PROC_NR);
pt_bind(newpt, &vmproc[VM_PROC_NR]);
pt_init_done = 1;
/* All OK. */
return;
}

2
servers/vm/glo.h
View file

@ -29,5 +29,3 @@ EXTERN long vm_sanitychecklevel;
/* total number of memory pages */
EXTERN int total_pages;
EXTERN int meminit_done;

7
servers/vm/main.c
View file

@ -332,14 +332,13 @@ void init_vm(void)
/* region management initialization. */
map_region_init();
/* Initialize tables to all physical memory. */
mem_init(mem_chunks);
/* Architecture-dependent initialization. */
init_proc(VM_PROC_NR);
pt_init();
/* Initialize tables to all physical memory. */
mem_init(mem_chunks);
meminit_done = 1;
/* Give these processes their own page table. */
for (ip = &kernel_boot_info.boot_procs[0];
ip < &kernel_boot_info.boot_procs[NR_BOOT_PROCS]; ip++) {

24
servers/vm/pagerange.h
View file

@ -1,24 +0,0 @@
#include <minix/callnr.h>
#include <minix/com.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/ds.h>
#include <minix/endpoint.h>
#include <minix/keymap.h>
#include <minix/minlib.h>
#include <minix/type.h>
#include <minix/ipc.h>
#include <minix/sysutil.h>
#include <minix/syslib.h>
#include <minix/const.h>
typedef struct pagerange {
phys_bytes addr; /* in pages */
phys_bytes size; /* in pages */
/* AVL fields */
struct pagerange *less, *greater; /* children */
int factor; /* AVL balance factor */
} pagerange_t;

3
servers/vm/slaballoc.c
View file

@ -18,7 +18,6 @@
#include <assert.h>
#include <errno.h>
#include <assert.h>
#include <string.h>
#include <env.h>
@ -387,7 +386,7 @@ void *slaballoc(int bytes)
/*===========================================================================*
* int objstats *
*===========================================================================*/
static int objstats(void *mem, int bytes,
static inline int objstats(void *mem, int bytes,
struct slabheader **sp, struct slabdata **fp, int *ip)
{
#if SANITYCHECKS