init gnumach copy

1 files changed, 243 insertions, 0 deletions

diff --git a/kern/slab.h b/kern/slab.h
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+/*
+ * Copyright (c) 2011 Free Software Foundation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/*
+ * Copyright (c) 2010, 2011 Richard Braun.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * Object caching memory allocator.
+ */
+
+#ifndef _KERN_SLAB_H
+#define _KERN_SLAB_H
+
+#include <cache.h>
+#include <kern/cpu_number.h>
+#include <kern/lock.h>
+#include <kern/list.h>
+#include <kern/rbtree.h>
+#include <mach/machine/vm_types.h>
+#include <sys/types.h>
+#include <vm/vm_types.h>
+
+struct kmem_cache;
+
+#if SLAB_USE_CPU_POOLS
+
+/*
+ * Per-processor cache of pre-constructed objects.
+ *
+ * The flags member is a read-only CPU-local copy of the parent cache flags.
+ */
+struct kmem_cpu_pool {
+    simple_lock_data_t lock;
+    int flags;
+    int size;
+    int transfer_size;
+    int nr_objs;
+    void **array;
+} __attribute__((aligned(CPU_L1_SIZE)));
+
+/*
+ * When a cache is created, its CPU pool type is determined from the buffer
+ * size. For small buffer sizes, many objects can be cached in a CPU pool.
+ * Conversely, for large buffer sizes, this would incur much overhead, so only
+ * a few objects are stored in a CPU pool.
+ */
+struct kmem_cpu_pool_type {
+    size_t buf_size;
+    int array_size;
+    size_t array_align;
+    struct kmem_cache *array_cache;
+};
+#endif /* SLAB_USE_CPU_POOLS */
+
+/*
+ * Buffer descriptor.
+ *
+ * For normal caches (i.e. without SLAB_CF_VERIFY), bufctls are located at the
+ * end of (but inside) each buffer. If SLAB_CF_VERIFY is set, bufctls are
+ * located after each buffer.
+ *
+ * When an object is allocated to a client, its bufctl isn't used. This memory
+ * is instead used for redzoning if cache debugging is in effect.
+ */
+union kmem_bufctl {
+    union kmem_bufctl *next;
+    unsigned long redzone;
+};
+
+/*
+ * Buffer tag.
+ *
+ * This structure is only used for SLAB_CF_VERIFY caches. It is located after
+ * the bufctl and includes information about the state of the buffer it
+ * describes (allocated or not). It should be thought of as a debugging
+ * extension of the bufctl.
+ */
+struct kmem_buftag {
+    unsigned long state;
+};
+
+/*
+ * Page-aligned collection of unconstructed buffers.
+ */
+struct kmem_slab {
+    struct kmem_cache *cache;
+    struct list list_node;
+    struct rbtree_node tree_node;
+    unsigned long nr_refs;
+    union kmem_bufctl *first_free;
+    void *addr;
+};
+
+/*
+ * Type for constructor functions.
+ *
+ * The pre-constructed state of an object is supposed to include only
+ * elements such as e.g. linked lists, locks, reference counters. Therefore
+ * constructors are expected to 1) never fail and 2) not need any
+ * user-provided data. The first constraint implies that object construction
+ * never performs dynamic resource allocation, which also means there is no
+ * need for destructors.
+ */
+typedef void (*kmem_cache_ctor_t)(void *obj);
+
+/*
+ * Cache name buffer size.  The size is chosen so that struct
+ * kmem_cache fits into two cache lines.  The size of a cache line on
+ * a typical CPU is 64 bytes.
+ */
+#define KMEM_CACHE_NAME_SIZE 24
+
+/*
+ * Cache of objects.
+ *
+ * Locking order : cpu_pool -> cache. CPU pools locking is ordered by CPU ID.
+ *
+ * Currently, SLAB_USE_CPU_POOLS is not defined.  KMEM_CACHE_NAME_SIZE
+ * is chosen so that the struct fits into two cache lines.  The first
+ * cache line contains all hot fields.
+ */
+struct kmem_cache {
+#if SLAB_USE_CPU_POOLS
+    /* CPU pool layer */
+    struct kmem_cpu_pool cpu_pools[NCPUS];
+    struct kmem_cpu_pool_type *cpu_pool_type;
+#endif /* SLAB_USE_CPU_POOLS */
+
+    /* Slab layer */
+    simple_lock_data_t lock;
+    struct list node;   /* Cache list linkage */
+    struct list partial_slabs;
+    struct list free_slabs;
+    struct rbtree active_slabs;
+    int flags;
+    size_t bufctl_dist; /* Distance from buffer to bufctl   */
+    size_t slab_size;
+    long_natural_t bufs_per_slab;
+    long_natural_t nr_objs;  /* Number of allocated objects */
+    long_natural_t nr_free_slabs;
+    kmem_cache_ctor_t ctor;
+    /* All fields below are cold  */
+    size_t obj_size;    /* User-provided size */
+    /* Assuming ! SLAB_USE_CPU_POOLS, here is the cacheline boundary */
+    size_t align;
+    size_t buf_size;    /* Aligned object size  */
+    size_t color;
+    size_t color_max;
+    long_natural_t nr_bufs;  /* Total number of buffers */
+    long_natural_t nr_slabs;
+    char name[KMEM_CACHE_NAME_SIZE];
+    size_t buftag_dist; /* Distance from buffer to buftag */
+    size_t redzone_pad; /* Bytes from end of object to redzone word */
+} __cacheline_aligned;
+
+/*
+ * Mach-style declarations for struct kmem_cache.
+ */
+typedef struct kmem_cache *kmem_cache_t;
+#define KMEM_CACHE_NULL ((kmem_cache_t) 0)
+
+/*
+ * Cache initialization flags.
+ */
+#define KMEM_CACHE_NOOFFSLAB    0x1 /* Don't allocate external slab data */
+#define KMEM_CACHE_PHYSMEM      0x2 /* Allocate from physical memory */
+#define KMEM_CACHE_VERIFY       0x4 /* Use debugging facilities */
+
+/*
+ * Initialize a cache.
+ */
+void kmem_cache_init(struct kmem_cache *cache, const char *name,
+                     size_t obj_size, size_t align,
+                     kmem_cache_ctor_t ctor, int flags);
+
+/*
+ * Allocate an object from a cache.
+ */
+vm_offset_t kmem_cache_alloc(struct kmem_cache *cache);
+
+/*
+ * Release an object to its cache.
+ */
+void kmem_cache_free(struct kmem_cache *cache, vm_offset_t obj);
+
+/*
+ * Initialize the memory allocator module.
+ */
+void slab_bootstrap(void);
+void slab_init(void);
+
+/*
+ * Release free slabs to the VM system.
+ */
+void slab_collect(void);
+
+/*
+ * Display a summary of all kernel caches.
+ */
+void slab_info(void);
+
+#if MACH_KDB
+void db_show_slab_info(void);
+void db_whatis_slab(vm_offset_t addr);
+#endif /* MACH_KDB */
+
+#endif /* _KERN_SLAB_H */