Fix various memory managment errors

A few errors were introduced in the latest changes.

o Add VM_PAGE_WAIT calls around physical allocation attempts in case of
memory exhaustion.
o Fix stack release.
o Fix memory exhaustion report.
o Fix free page accounting.

* kern/slab.c (kmem_pagealloc, kmem_pagefree): New functions
(kmem_slab_create, kmem_slab_destroy, kalloc, kfree): Use kmem_pagealloc
and kmem_pagefree instead of the raw page allocation functions.
(kmem_cache_compute_sizes): Don't store slab order.
* kern/slab.h (struct kmem_cache): Remove `slab_order' member.
* kern/thread.c (stack_alloc): Call VM_PAGE_WAIT in case of memory
exhaustion.
(stack_collect): Call vm_page_free_contig instead of kmem_free to
release pages.
* vm/vm_page.c (vm_page_seg_alloc): Fix memory exhaustion report.
(vm_page_setup): Don't update vm_page_free_count.
(vm_page_free_pa): Check page parameter.
(vm_page_mem_free): New function.
* vm/vm_page.h (vm_page_free_count): Remove extern declaration.
(vm_page_mem_free): New prototype.
* vm/vm_pageout.c: Update comments not to refer to vm_page_free_count.
(vm_pageout_scan, vm_pageout_continue, vm_pageout): Use vm_page_mem_free
instead of vm_page_free_count, update types accordingly.
* vm/vm_resident.c (vm_page_free_count, vm_page_free_count_minimum):
Remove variables.
(vm_page_free_avail): New variable.
(vm_page_bootstrap, vm_page_grab, vm_page_release, vm_page_grab_contig,
vm_page_free_contig, vm_page_wait): Use vm_page_mem_free instead of vm_page_free_count,
update types accordingly, don't set vm_page_free_count_minimum.
* vm/vm_user.c (vm_statistics): Likewise.

1 files changed, 17 insertions, 11 deletions

diff --git a/kern/thread.c b/kern/thread.c
index 91e08697..d8d6af57 100644
--- a/kern/thread.c
+++ b/kern/thread.c
@@ -197,16 +197,19 @@ kern_return_t stack_alloc(
 	if (stack == 0) {
 		struct vm_page *page;
 
-		/*
-		 *	Kernel stacks should be naturally aligned,
-		 *	so that it is easy to find the starting/ending
-		 *	addresses of a stack given an address in the middle.
-		 */
-		page = vm_page_alloc_pa(vm_page_order(KERNEL_STACK_SIZE),
-					VM_PAGE_SEL_DIRECTMAP,
-					VM_PT_STACK);
-		if (page == NULL)
-			return KERN_RESOURCE_SHORTAGE;
+		for (;;) {
+			/*
+			 *	Kernel stacks should be naturally aligned,
+			 *	so that it is easy to find the starting/ending
+			 *	addresses of a stack given an address in the middle.
+			 */
+			page = vm_page_grab_contig(KERNEL_STACK_SIZE,
+						   VM_PAGE_SEL_DIRECTMAP);
+			if (page != NULL)
+				break;
+
+			VM_PAGE_WAIT(NULL);
+		}
 
 		stack = phystokv(vm_page_to_pa(page));
 #if	MACH_DEBUG
@@ -254,6 +257,7 @@ void stack_free(
 
 void stack_collect(void)
 {
+	struct vm_page *page;
 	vm_offset_t stack;
 	spl_t s;
 
@@ -269,7 +273,9 @@ void stack_collect(void)
 #if	MACH_DEBUG
 		stack_finalize(stack);
 #endif	/* MACH_DEBUG */
-		kmem_free(kmem_map, stack, KERNEL_STACK_SIZE);
+		page = vm_page_lookup_pa(kvtophys(stack));
+		assert(page != NULL);
+		vm_page_free_contig(page, KERNEL_STACK_SIZE);
 
 		s = splsched();
 		stack_lock();