osfmk/kern/btlog.h

   1 /*
   2  * Copyright (c) 2012 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #ifndef _KERN_BTLOG_H_
  30 #define _KERN_BTLOG_H_
  31
  32 #include <kern/kern_types.h>
  33 #include <kern/debug.h>
  34 #include <sys/cdefs.h>
  35 #include <stdint.h>
  36
  37 #ifdef  XNU_KERNEL_PRIVATE
  38
  39 /*
  40  * The btlog subsystem allows for fast unobtrusive backtraces
  41  * to be recorded and maintained in chronological order.
  42  *
  43  * Each backtrace is associated with an element/object,
  44  * and an operation. For example, memory allocations and
  45  * frees can be tracked with this infrastructure. So
  46  * can refcounts. The "operation" namespace is maintained
  47  * by the caller.
  48  *
  49  * When the event buffer fills, records are reused in FIFO
  50  * order.
  51  *
  52  * When a btlog_t is created, callbacks can be provided
  53  * to ensure proper locking of the datastructures. If these
  54  * are not provided, the caller is responsible for
  55  * preventing simultaneous modification.
  56  */
  57
  58 /*
  59  * BTLOG_MAX_DEPTH configures how deep of a stack trace is stored.  15
  60  * levels is usually enough to get past all the layers of code in
  61  * kalloc and IOKit and see who the actual caller is up above these
  62  * lower levels, when used by the zone allocator logging code.
  63  */
  64
  65 #define BTLOG_MAX_DEPTH 15
  66
  67 struct btlog;
  68 typedef struct btlog btlog_t;
  69
  70 extern btlog_t *btlog_create(size_t numrecords,
  71                              size_t record_btdepth,
  72                              boolean_t caller_will_remove_entries_for_element);
  73
  74 extern void btlog_add_entry(btlog_t *btlog,
  75                             void *element,
  76                             uint8_t operation,
  77                             void *bt[],
  78                             size_t btcount);
  79
  80 extern void btlog_remove_entries_for_element(btlog_t *btlog,
  81                                              void *element);
  82
  83 #if DEBUG || DEVELOPMENT
  84 void btlog_copy_backtraces_for_elements(btlog_t      * btlog,
  85                                         uintptr_t    * instances,
  86                                         uint32_t     * count,
  87                                         uint32_t       zoneSize,
  88                                         leak_site_proc proc,
  89                                         void         * refCon);
  90 #endif  /* DEBUG || DEVELOPMENT */
  91
  92 #endif  /* XNU_KERNEL_PRIVATE */
  93
  94 #endif  /* _KERN_BTLOG_H_ */