Merge branch 'scale-amd64' of ssh://amsterdam.csail.mit.edu/home/am0/6.828/xv6 into scale-amd64

Conflicts: main.c

Merge branch 'scale-amd64' of ssh://amsterdam.csail.mit.edu/home/am0/6.828/xv6 into scale-amd64
f56e01e3 · Frans Kaashoek · 0b085451 · b3922680 · f56e01e3 · f56e01e3
--- a/boot.S
+++ b/boot.S
@@ -86,7 +86,7 @@ start32:
 	call initpagetables
        call init32e

-        movl $PADDR(start64), %edi
+	movl $PADDR(start64), %eax
 	# Enter 64-bit mode.
 	ljmp $KCSEG, $PADDR(tramp64)  // code64 segment selector

@@ -107,7 +107,7 @@ apstart:

 apstart32:
        call init32e
-        movl $PADDR(apstart64), %edi
+	movl $PADDR(apstart64), %eax
 	ljmp $KCSEG, $PADDR(tramp64)  // code64 segment selector

 .code64       
@@ -124,11 +124,11 @@ apstart64:
 tramp64:
 	# The linker thinks we are running at tramp64, but we're actually
 	# running at PADDR(tramp64), so use an explicit calculation to
-	# load and jump to the correct address.  %rdi should hold the
+	# load and jump to the correct address.  %rax should hold the
 	# physical address of the jmp target.
 	movq $KBASE, %r11
-	addq %r11, %rdi
-	jmp *%rdi
+	addq %r11, %rax
+	jmp *%rax

 # Initial stack
 .comm stack, STACK

--- a/e820.h
+++ b/e820.h
--- a/kalloc.c
+++ b/kalloc.c
@@ -9,6 +9,11 @@
 #include "kalloc.h"
 #include "mtrace.h"
 #include "cpu.h"
+#include "multiboot.h"
+
+static struct Mbmem mem[128];
+static u64 nmem;
+static u64 membytes;

 struct kmem kmems[NCPU];
 struct kmem kstacks[NCPU];
@@ -19,6 +24,77 @@ enum { kalloc_memset = 0 };

 static int kinited __mpalign__;

+static struct Mbmem *
+memsearch(paddr pa)
+{
+  struct Mbmem *e;
+  struct Mbmem *q;
+
+  q = mem+nmem;
+  for (e = &mem[0]; e < q; e++)
+    if ((e->base <= pa) && ((e->base+e->length) > pa))
+      return e;
+  return NULL;
+}
+
+static u64
+memsize(void *va)
+{
+  struct Mbmem *e;
+  paddr pa = v2p(va);
+
+  e = memsearch(pa);
+  if (e == NULL)
+    return -1;
+  return (e->base+e->length) - pa;
+}
+
+static void *
+memnext(void *va, u64 inc)
+{
+  struct Mbmem *e, *q;
+  paddr pa = v2p(va);
+
+  e = memsearch(pa);
+  if (e == NULL)
+    return (void *)-1;
+
+  pa += inc;
+  if (pa < (e->base+e->length))
+    return p2v(pa);
+
+  q = mem+nmem;
+  for (e = e + 1; e < q; e++)
+      return p2v(e->base);
+
+  return (void *)-1;
+}
+
+static void
+initmem(u64 mbaddr)
+{
+  struct Mbdata *mb;
+  struct Mbmem *mbmem;
+  u8 *p, *ep;
+
+  mb = p2v(mbaddr);
+  if(!(mb->flags & (1<<6)))
+    panic("multiboot header has no memory map");
+
+  p = p2v(mb->mmap_addr);
+  ep = p + mb->mmap_length;
+
+  while (p < ep) {
+    mbmem = (Mbmem *)(p+4);
+    p += 4 + *(u32*)p;
+    if (mbmem->type == 1) {
+      membytes += mbmem->length;
+      mem[nmem] = *mbmem;
+      nmem++;
+    }
+  }
+}
+
 // simple page allocator to get off the ground during boot
 static char *
 pgalloc(void)
@@ -41,7 +117,7 @@ kfree_pool(struct kmem *m, char *v)
 {
  struct run *r;

-  if((uptr)v % PGSIZE || v < end || v2p(v) >= PHYSTOP)
+  if((uptr)v % PGSIZE || v < end || memsize(v) == -1ull)
    panic("kfree_pool");

  // Fill with junk to catch dangling refs.
@@ -147,10 +223,13 @@ kminit(void)

 // Initialize free list of physical pages.
 void
-initkalloc(void)
+initkalloc(u64 mbaddr)
 {
  char *p;
-  char *e;
+  u64 n;
+  u64 k;
+
+  initmem(mbaddr);

  for (int c = 0; c < NCPU; c++) {
    kmems[c].name[0] = (char) c + '0';
@@ -166,18 +245,35 @@ initkalloc(void)
    kstacks[c].size = KSTACKSIZE;
  }

+  cprintf("%lu mbytes\n", membytes / (1<<20));
+  n = membytes / NCPU;
+  if (n & (PGSIZE-1)) {
+    cprintf("bytes/CPU isn't aligned\n");
+    n = PGROUNDDOWN(n);
+  }
+
  p = (char*)PGROUNDUP((uptr)newend);
-  e = (char*)KBASE;
+  k = (((uptr)p) - KBASE);
  for (int c = 0; c < NCPU; c++) {
-    char *sp = p + CPUKSTACKS*KSTACKSIZE;
-    char *ep = e + (PHYSTOP/NCPU);
-    if (sp >= ep)
-      panic("Too many stacks");
-    for (; p < sp; p += KSTACKSIZE)
+    // Fill the stack allocator
+    for (int i = 0; i < CPUKSTACKS; i++, k += KSTACKSIZE) {
+      if (p == (void *)-1)
+        panic("initkalloc: e820next");
+      // XXX(sbw) handle this condition
+      if (memsize(p) < KSTACKSIZE)
+        panic("initkalloc: e820size");
      kfree_pool(&kstacks[c], p);
-    for (; p < ep; p += PGSIZE)
+      p = memnext(p, KSTACKSIZE);
+    }
+   
+    // The rest goes to the page allocator
+    for (; k != n; k += PGSIZE, p = memnext(p, PGSIZE)) {
+      if (p == (void *)-1)
+        panic("initkalloc: e820next");
      kfree_pool(&kmems[c], p);
-    e = p;
+    }
+
+    k = 0;
  }

  kminit();

--- a/main.c
+++ b/main.c
@@ -2,6 +2,7 @@
 #include "multiboot.h"
 #include "kernel.h"
 #include "cpu.h"
+#include "e820.h"

 extern void initpic(void);
 extern void initioapic(void);
@@ -14,7 +15,7 @@ extern void initlapic(void);
 extern void inittls(void);
 extern void inittrap(void);
 extern void initseg(void);
-extern void initkalloc(void);
+extern void initkalloc(u64 mbaddr);
 extern void initrcu(void);
 extern void initproc(void);
 extern void initbio(void);
@@ -74,7 +75,7 @@ bootothers(void)
 }

 void
-cmain(void)
+cmain(u64 mbmagic, u64 mbaddr)
 {
  extern pml4e_t kpml4[];
  extern u64 cpuhz;
@@ -91,9 +92,8 @@ cmain(void)
  inittrap();
  initmp();
  initlapic();
-
-  initkalloc();
-  initgc();       // initialize rcu module
+  initkalloc(mbaddr);
+  initgc();        // gc epochs
  initproc();      // process table
  initbio();       // buffer cache
  initinode();     // inode cache