impove memory accounting

. the total amount of memory in the system didn't include the memory
	  used by the boot-time modules and some dynamic allocation by the
	  kernel at boot time (to map in VM). especially apparent on our
	  ARM board with 'only' 512MB of memory and a huge ramdisk.
	. also: *add* the VM loaded module to the freelist after it has
	  been allocated for & mapped in instead of cutting it *out* of the
	  freelist! so we get a few more MB free..

Change-Id: If37ac32b21c9d38610830e21421264da4f20bc4f

include/minix/param.h

@@ -42,6 +42,7 @@ typedef struct kinfo {
         char version[6];        /* kernel version number */
 	int vm_allocated_bytes; /* allocated by kernel to load vm */
 	int kernel_allocated_bytes;		/* used by kernel */
+	int kernel_allocated_bytes_dynamic;	/* used by kernel (runtime) */
 } kinfo_t;
 
 #endif

kernel/arch/earm/pg_utils.c

@@ -67,26 +67,6 @@ void cut_memmap(kinfo_t *cbi, phys_bytes start, phys_bytes end)
         }
 }
 
-phys_bytes alloc_lowest(kinfo_t *cbi, phys_bytes len)
-{
-	/* Allocate the lowest physical page we have. */
-	int m;
-#define EMPTY 0xffffffff
-	phys_bytes lowest = EMPTY;
-	assert(len > 0);
-	len = roundup(len, ARM_PAGE_SIZE);
-
-	assert(kernel_may_alloc);
-
-	for(m = 0; m < cbi->mmap_size; m++) {
-		if(cbi->memmap[m].len < len) continue;
-		if(cbi->memmap[m].addr < lowest) lowest = cbi->memmap[m].addr;
-	}
-	assert(lowest != EMPTY);
-	cut_memmap(cbi, lowest, len);
-	return lowest;
-}
-
 void add_memmap(kinfo_t *cbi, u64_t addr, u64_t len)
 {
         int m;
@@ -157,6 +137,8 @@ phys_bytes pg_alloc_page(kinfo_t *cbi)
 		mmap->addr += ARM_PAGE_SIZE;
 		mmap->len  -= ARM_PAGE_SIZE;
 
+		cbi->kernel_allocated_bytes_dynamic += ARM_PAGE_SIZE;
+
 		return addr;
 	}
 

kernel/arch/earm/pre_init.c

@@ -106,8 +106,8 @@ int overlaps(multiboot_module_t *mod, int n, int cmp_mod)
 #define MB_PARAM_MOD  0x96000000
 #define MB_MODS_ALIGN 0x00800000 /*  8 MB */
 #define MB_MODS_SIZE  0x00004000 /* 16 KB */
-#define MB_MMAP_START MB_MODS_BASE
-#define MB_MMAP_SIZE  0x10000000 /* 256 MB */
+#define MB_MMAP_START 0x80000000
+#define MB_MMAP_SIZE  0x20000000 /* 512 MB */
 
 multiboot_module_t mb_modlist[MB_MODS_NR];
 multiboot_memory_map_t mb_memmap;
@@ -204,6 +204,7 @@ void get_parameters(u32_t ebx, kinfo_t *cbi)
 	 * still needed but will be freed after bootstrapping.
 	 */
 	kinfo.kernel_allocated_bytes = (phys_bytes) &_kern_size;
+	kinfo.kernel_allocated_bytes -= cbi->bootstrap_len;
 
 	assert(!(cbi->bootstrap_start % ARM_PAGE_SIZE));
 	cbi->bootstrap_len = rounddown(cbi->bootstrap_len, ARM_PAGE_SIZE);

kernel/arch/earm/protect.c

@@ -151,7 +151,8 @@ void arch_boot_proc(struct boot_image *ip, struct proc *rp)
 		arch_proc_init(rp, execi.pc, kinfo.user_sp - 3*4, ip->proc_name);
 
 		/* Free VM blob that was just copied into existence. */
-		cut_memmap(&kinfo, mod->mod_start, mod->mod_end);
+		add_memmap(&kinfo, mod->mod_start, mod->mod_end-mod->mod_start);
+		mod->mod_end = mod->mod_start = 0;
 
 		/* Remember them */
 		kinfo.vm_allocated_bytes = alloc_for_vm;

kernel/arch/i386/pg_utils.c

@@ -81,6 +81,7 @@ phys_bytes alloc_lowest(kinfo_t *cbi, phys_bytes len)
 	}
 	assert(lowest != EMPTY);
 	cut_memmap(cbi, lowest, len);
+	cbi->kernel_allocated_bytes_dynamic += len;
 	return lowest;
 }
 
@@ -152,6 +153,8 @@ phys_bytes pg_alloc_page(kinfo_t *cbi)
 
 		mmap->len -= I386_PAGE_SIZE;
 
+                cbi->kernel_allocated_bytes_dynamic += I386_PAGE_SIZE;
+
 		return mmap->addr + mmap->len;
 	}
 

kernel/arch/i386/pre_init.c

@@ -164,6 +164,7 @@ void get_parameters(u32_t ebx, kinfo_t *cbi)
 	 * still needed but will be freed after bootstrapping.
 	 */
 	kinfo.kernel_allocated_bytes = (phys_bytes) &_kern_size;
+	kinfo.kernel_allocated_bytes -= cbi->bootstrap_len;
 
 	assert(!(cbi->bootstrap_start % I386_PAGE_SIZE));
 	cbi->bootstrap_len = rounddown(cbi->bootstrap_len, I386_PAGE_SIZE);

kernel/arch/i386/protect.c

@@ -428,7 +428,8 @@ void arch_boot_proc(struct boot_image *ip, struct proc *rp)
 		arch_proc_init(rp, execi.pc, kinfo.user_sp - 3*4, ip->proc_name);
 
 		/* Free VM blob that was just copied into existence. */
-		cut_memmap(&kinfo, mod->mod_start, mod->mod_end);
+		add_memmap(&kinfo, mod->mod_start, mod->mod_end-mod->mod_start);
+                mod->mod_end = mod->mod_start = 0;
 
 		/* Remember them */
 		kinfo.vm_allocated_bytes = alloc_for_vm;

servers/vm/alloc.c

@@ -97,6 +97,11 @@ phys_clicks alloc_mem(phys_clicks clicks, u32_t memflags)
   return mem;
 }
 
+void mem_add_total_pages(int pages)
+{
+	total_pages += pages;
+}
+
 /*===========================================================================*
  *				free_mem				     *
  *===========================================================================*/

servers/vm/main.c

@@ -306,6 +306,8 @@ void init_vm(void)
 	static struct memory mem_chunks[NR_MEMS];
 	static struct boot_image *ip;
 	extern void __minix_init(void);
+	multiboot_module_t *mod;
+	vir_bytes kern_dyn, kern_static;
 
 #if SANITYCHECKS
 	incheck = nocheck = 0;
@@ -344,6 +346,21 @@ void init_vm(void)
 	init_proc(VM_PROC_NR);
 	pt_init();
 
+	/* The kernel's freelist does not include boot-time modules; let
+	 * the allocator know that the total memory is bigger.
+	 */
+	for (mod = &kernel_boot_info.module_list[0];
+		mod < &kernel_boot_info.module_list[kernel_boot_info.mods_with_kernel-1]; mod++) {
+		phys_bytes len = mod->mod_end-mod->mod_start+1;
+		len = roundup(len, VM_PAGE_SIZE);
+		mem_add_total_pages(len/VM_PAGE_SIZE);
+	}
+
+	kern_dyn = kernel_boot_info.kernel_allocated_bytes_dynamic;
+	kern_static = kernel_boot_info.kernel_allocated_bytes;
+	kern_static = roundup(kern_static, VM_PAGE_SIZE);
+	mem_add_total_pages((kern_dyn + kern_static)/VM_PAGE_SIZE);
+
 	/* 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++) {

servers/vm/proto.h

@@ -26,6 +26,7 @@ void usedpages_reset(void);
 int usedpages_add_f(phys_bytes phys, phys_bytes len, char *file, int
 	line);
 void free_mem(phys_clicks base, phys_clicks clicks);
+void mem_add_total_pages(int pages);
 #define usedpages_add(a, l) usedpages_add_f(a, l, __FILE__, __LINE__)
 
 void mem_init(struct memory *chunks);

servers/vm/region.c

@@ -1462,7 +1462,8 @@ void get_stats_info(struct vm_stats_info *vsi)
 void get_usage_info_kernel(struct vm_usage_info *vui)
 {
 	memset(vui, 0, sizeof(*vui));
-	vui->vui_total = kernel_boot_info.kernel_allocated_bytes;
+	vui->vui_total = kernel_boot_info.kernel_allocated_bytes +
+		kernel_boot_info.kernel_allocated_bytes_dynamic;
 }
 
 static void get_usage_info_vm(struct vm_usage_info *vui)