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Memory allocator ok

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This commit is contained in:
ridethepig 2023-02-02 14:36:27 +00:00
parent ad57ec8cb9
commit 8728adbd0b
1 changed files with 35 additions and 14 deletions
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49
kernel/kalloc.c
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@ -19,14 +19,19 @@ struct run {
}; };
struct { struct {
struct spinlock lock; struct spinlock lock[NCPU];
struct run *freelist; struct run *freelist[NCPU];
} kmem; } kmem;
static char kmem_lock_names [NCPU][10]; // ugly but have-to impl
void void
kinit() kinit()
{ {
initlock(&kmem.lock, "kmem"); for (int i = 0; i < NCPU; ++ i) {
snprintf(kmem_lock_names[i], NELEM(kmem_lock_names[0]), "kmem%d", i);
initlock(&kmem.lock[i], kmem_lock_names[i]);
}
freerange(end, (void*)PHYSTOP); freerange(end, (void*)PHYSTOP);
} }
@ -55,11 +60,13 @@ kfree(void *pa)
memset(pa, 1, PGSIZE); memset(pa, 1, PGSIZE);
r = (struct run*)pa; r = (struct run*)pa;
push_off();
acquire(&kmem.lock); int _cpu = cpuid();
r->next = kmem.freelist; acquire(&kmem.lock[_cpu]);
kmem.freelist = r; r->next = kmem.freelist[_cpu];
release(&kmem.lock); kmem.freelist[_cpu] = r;
release(&kmem.lock[_cpu]);
pop_off();
} }
// Allocate one 4096-byte page of physical memory. // Allocate one 4096-byte page of physical memory.
@ -69,13 +76,27 @@ void *
kalloc(void) kalloc(void)
{ {
struct run *r; struct run *r;
push_off();
acquire(&kmem.lock); int _cpu = cpuid();
r = kmem.freelist; acquire(&kmem.lock[_cpu]);
r = kmem.freelist[_cpu];
if(r) if(r)
kmem.freelist = r->next; kmem.freelist[_cpu] = r->next;
release(&kmem.lock); else {
for (int i = 0, found = 0; i < NCPU && !found; ++ i) {
if (i != _cpu) {
acquire(&kmem.lock[i]);
if (kmem.freelist[i]) {
r = kmem.freelist[i];
kmem.freelist[i] = r->next;
found = 1;
}
release(&kmem.lock[i]);
}
}
}
release(&kmem.lock[_cpu]);
pop_off();
if(r) if(r)
memset((char*)r, 5, PGSIZE); // fill with junk memset((char*)r, 5, PGSIZE); // fill with junk
return (void*)r; return (void*)r;