Stack the slab allocator directly on top of the physical allocator

In order to increase the amount of memory available for kernel objects,
without reducing the amount of memory available for user processes,
a new allocation strategy is introduced in this change.

Instead of allocating kernel objects out of kernel virtual memory,
the slab allocator directly uses the direct mapping of physical
memory as its backend. This largely increases the kernel heap, and
removes the need for address translation updates.

In order to allow this strategy, an assumption made by the interrupt
code had to be removed. In addition, kernel stacks are now also
allocated directly from the physical allocator.

* i386/i386/db_trace.c: Include i386at/model_dep.h
(db_i386_reg_value): Update stack check.
* i386/i386/locore.S (trap_from_kernel, all_intrs,
int_from_intstack): Update interrupt handling.
* i386/i386at/model_dep.c: Include kern/macros.h.
(int_stack, int_stack_base): New variables.
(int_stack_high): Remove variable.
(i386at_init): Update interrupt stack initialization.
* i386/i386at/model_dep.h: Include i386/vm_param.h.
(int_stack_top, int_stack_base): New extern declarations.
(ON_INT_STACK): New macro.
* kern/slab.c: Include vm/vm_page.h
(KMEM_CF_NO_CPU_POOL, KMEM_CF_NO_RECLAIM): Remove macros.
(kmem_pagealloc, kmem_pagefree, kalloc_pagealloc, kalloc_pagefree): Remove
functions.
(kmem_slab_create): Allocate slab pages directly from the physical allocator.
(kmem_slab_destroy): Release slab pages directly to the physical allocator.
(kmem_cache_compute_sizes): Update the slab size computation algorithm to
return a power-of-two suitable for the physical allocator.
(kmem_cache_init): Remove custom allocation function pointers.
(kmem_cache_reap): Remove check on KMEM_CF_NO_RECLAIM.
(slab_init, kalloc_init): Update calls to kmem_cache_init.
(kalloc, kfree): Directly fall back on the physical allocator for big
allocation sizes.
(host_slab_info): Remove checks on defunct flags.
* kern/slab.h (kmem_slab_alloc_fn_t, kmem_slab_free_fn_t): Remove types.
(struct kmem_cache): Add `slab_order' member, remove `slab_alloc_fn' and
`slab_free_fn' members.
(KMEM_CACHE_NOCPUPOOL, KMEM_CACHE_NORECLAIM): Remove macros.
(kmem_cache_init): Update prototype, remove custom allocation functions.
* kern/thread.c (stack_alloc): Allocate stacks from the physical allocator.
* vm/vm_map.c (vm_map_kentry_cache, kentry_data, kentry_data_size): Remove
variables.
(kentry_pagealloc): Remove function.
(vm_map_init): Update calls to kmem_cache_init, remove initialization of
vm_map_kentry_cache.
(vm_map_create, _vm_map_entry_dispose, vm_map_copyout): Unconditionnally
use vm_map_entry_cache.
* vm/vm_map.h (kentry_data, kentry_data_size, kentry_count): Remove extern
declarations.
* vm/vm_page.h (VM_PT_STACK): New page type.
* device/dev_lookup.c (dev_lookup_init): Update calls to kmem_cache_init.
* device/dev_pager.c (dev_pager_hash_init, device_pager_init): Likewise.
* device/ds_routines.c (mach_device_init, mach_device_trap_init): Likewise.
* device/net_io.c (net_io_init): Likewise.
* i386/i386/fpu.c (fpu_module_init): Likewise.
* i386/i386/machine_task.c (machine_task_module_init): Likewise.
* i386/i386/pcb.c (pcb_module_init): Likewise.
* i386/intel/pmap.c (pmap_init): Likewise.
* ipc/ipc_init.c (ipc_bootstrap): Likewise.
* ipc/ipc_marequest.c (ipc_marequest_init): Likewise.
* kern/act.c (global_act_init): Likewise.
* kern/processor.c (pset_sys_init): Likewise.
* kern/rdxtree.c (rdxtree_cache_init): Likewise.
* kern/task.c (task_init): Likewise.
* vm/memory_object_proxy.c (memory_object_proxy_init): Likewise.
* vm/vm_external.c (vm_external_module_initialize): Likewise.
* vm/vm_fault.c (vm_fault_init): Likewise.
* vm/vm_object.c (vm_object_bootstrap): Likewise.
* vm/vm_resident.c (vm_page_module_init): Likewise.
(vm_page_bootstrap): Remove initialization of kentry_data.

1 files changed, 6 insertions, 11 deletions

diff --git a/i386/i386at/model_dep.c b/i386/i386at/model_dep.c
index 7638b832..62763ae1 100644
--- a/i386/i386at/model_dep.c
+++ b/i386/i386at/model_dep.c
@@ -47,6 +47,7 @@
 #include <kern/cpu_number.h>
 #include <kern/debug.h>
 #include <kern/mach_clock.h>
+#include <kern/macros.h>
 #include <kern/printf.h>
 #include <kern/startup.h>
 #include <sys/time.h>
@@ -133,8 +134,9 @@ extern char	version[];
 /* If set, reboot the system on ctrl-alt-delete.  */
 boolean_t	rebootflag = FALSE;	/* exported to kdintr */
 
-/* XX interrupt stack pointer and highwater mark, for locore.S.  */
-vm_offset_t int_stack_top, int_stack_high;
+/* Interrupt stack.  */
+static char int_stack[KERNEL_STACK_SIZE] __aligned(KERNEL_STACK_SIZE);
+vm_offset_t int_stack_top, int_stack_base;
 
 #ifdef LINUX_DEV
 extern void linux_init(void);
@@ -398,11 +400,6 @@ i386at_init(void)
 	pmap_clear_bootstrap_pagetable((void *)boot_info.pt_base);
 #endif	/* MACH_PV_PAGETABLES */
 
-	/* Interrupt stacks are allocated in physical memory,
-	   while kernel stacks are allocated in kernel virtual memory,
-	   so phys_last_addr serves as a convenient dividing point.  */
-	int_stack_high = phystokv(phys_last_addr);
-
 	/*
 	 * Initialize and activate the real i386 protected-mode structures.
 	 */
@@ -448,10 +445,8 @@ i386at_init(void)
 	hyp_p2m_init();
 #endif	/* MACH_XEN */
 
-	/* XXX We'll just use the initialization stack we're already running on
-	   as the interrupt stack for now.  Later this will have to change,
-	   because the init stack will get freed after bootup.  */
-	asm("movl %%esp,%0" : "=m" (int_stack_top));
+	int_stack_base = (vm_offset_t)&int_stack;
+	int_stack_top = int_stack_base + KERNEL_STACK_SIZE - 4;
 }
 
 /*