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sgen-gc.c
5373 lines (4566 loc) · 163 KB
/
sgen-gc.c
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/*
* sgen-gc.c: Simple generational GC.
*
* Author:
* Paolo Molaro (lupus@ximian.com)
* Rodrigo Kumpera (kumpera@gmail.com)
*
* Copyright 2005-2011 Novell, Inc (http://www.novell.com)
* Copyright 2011 Xamarin Inc (http://www.xamarin.com)
*
* Thread start/stop adapted from Boehm's GC:
* Copyright (c) 1994 by Xerox Corporation. All rights reserved.
* Copyright (c) 1996 by Silicon Graphics. All rights reserved.
* Copyright (c) 1998 by Fergus Henderson. All rights reserved.
* Copyright (c) 2000-2004 by Hewlett-Packard Company. All rights reserved.
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
*
* Permission is hereby granted to use or copy this program
* for any purpose, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*
*
* Copyright 2001-2003 Ximian, Inc
* Copyright 2003-2010 Novell, Inc.
* Copyright 2011 Xamarin, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*
* Important: allocation provides always zeroed memory, having to do
* a memset after allocation is deadly for performance.
* Memory usage at startup is currently as follows:
* 64 KB pinned space
* 64 KB internal space
* size of nursery
* We should provide a small memory config with half the sizes
*
* We currently try to make as few mono assumptions as possible:
* 1) 2-word header with no GC pointers in it (first vtable, second to store the
* forwarding ptr)
* 2) gc descriptor is the second word in the vtable (first word in the class)
* 3) 8 byte alignment is the minimum and enough (not true for special structures (SIMD), FIXME)
* 4) there is a function to get an object's size and the number of
* elements in an array.
* 5) we know the special way bounds are allocated for complex arrays
* 6) we know about proxies and how to treat them when domains are unloaded
*
* Always try to keep stack usage to a minimum: no recursive behaviour
* and no large stack allocs.
*
* General description.
* Objects are initially allocated in a nursery using a fast bump-pointer technique.
* When the nursery is full we start a nursery collection: this is performed with a
* copying GC.
* When the old generation is full we start a copying GC of the old generation as well:
* this will be changed to mark&sweep with copying when fragmentation becomes to severe
* in the future. Maybe we'll even do both during the same collection like IMMIX.
*
* The things that complicate this description are:
* *) pinned objects: we can't move them so we need to keep track of them
* *) no precise info of the thread stacks and registers: we need to be able to
* quickly find the objects that may be referenced conservatively and pin them
* (this makes the first issues more important)
* *) large objects are too expensive to be dealt with using copying GC: we handle them
* with mark/sweep during major collections
* *) some objects need to not move even if they are small (interned strings, Type handles):
* we use mark/sweep for them, too: they are not allocated in the nursery, but inside
* PinnedChunks regions
*/
/*
* TODO:
*) we could have a function pointer in MonoClass to implement
customized write barriers for value types
*) investigate the stuff needed to advance a thread to a GC-safe
point (single-stepping, read from unmapped memory etc) and implement it.
This would enable us to inline allocations and write barriers, for example,
or at least parts of them, like the write barrier checks.
We may need this also for handling precise info on stacks, even simple things
as having uninitialized data on the stack and having to wait for the prolog
to zero it. Not an issue for the last frame that we scan conservatively.
We could always not trust the value in the slots anyway.
*) modify the jit to save info about references in stack locations:
this can be done just for locals as a start, so that at least
part of the stack is handled precisely.
*) test/fix endianess issues
*) Implement a card table as the write barrier instead of remembered
sets? Card tables are not easy to implement with our current
memory layout. We have several different kinds of major heap
objects: Small objects in regular blocks, small objects in pinned
chunks and LOS objects. If we just have a pointer we have no way
to tell which kind of object it points into, therefore we cannot
know where its card table is. The least we have to do to make
this happen is to get rid of write barriers for indirect stores.
(See next item)
*) Get rid of write barriers for indirect stores. We can do this by
telling the GC to wbarrier-register an object once we do an ldloca
or ldelema on it, and to unregister it once it's not used anymore
(it can only travel downwards on the stack). The problem with
unregistering is that it needs to happen eventually no matter
what, even if exceptions are thrown, the thread aborts, etc.
Rodrigo suggested that we could do only the registering part and
let the collector find out (pessimistically) when it's safe to
unregister, namely when the stack pointer of the thread that
registered the object is higher than it was when the registering
happened. This might make for a good first implementation to get
some data on performance.
*) Some sort of blacklist support? Blacklists is a concept from the
Boehm GC: if during a conservative scan we find pointers to an
area which we might use as heap, we mark that area as unusable, so
pointer retention by random pinning pointers is reduced.
*) experiment with max small object size (very small right now - 2kb,
because it's tied to the max freelist size)
*) add an option to mmap the whole heap in one chunk: it makes for many
simplifications in the checks (put the nursery at the top and just use a single
check for inclusion/exclusion): the issue this has is that on 32 bit systems it's
not flexible (too much of the address space may be used by default or we can't
increase the heap as needed) and we'd need a race-free mechanism to return memory
back to the system (mprotect(PROT_NONE) will still keep the memory allocated if it
was written to, munmap is needed, but the following mmap may not find the same segment
free...)
*) memzero the major fragments after restarting the world and optionally a smaller
chunk at a time
*) investigate having fragment zeroing threads
*) separate locks for finalization and other minor stuff to reduce
lock contention
*) try a different copying order to improve memory locality
*) a thread abort after a store but before the write barrier will
prevent the write barrier from executing
*) specialized dynamically generated markers/copiers
*) Dynamically adjust TLAB size to the number of threads. If we have
too many threads that do allocation, we might need smaller TLABs,
and we might get better performance with larger TLABs if we only
have a handful of threads. We could sum up the space left in all
assigned TLABs and if that's more than some percentage of the
nursery size, reduce the TLAB size.
*) Explore placing unreachable objects on unused nursery memory.
Instead of memset'ng a region to zero, place an int[] covering it.
A good place to start is add_nursery_frag. The tricky thing here is
placing those objects atomically outside of a collection.
*) Allocation should use asymmetric Dekker synchronization:
http://blogs.oracle.com/dave/resource/Asymmetric-Dekker-Synchronization.txt
This should help weak consistency archs.
*/
#include "config.h"
#ifdef HAVE_SGEN_GC
#ifdef __MACH__
#undef _XOPEN_SOURCE
#define _XOPEN_SOURCE
#define _DARWIN_C_SOURCE
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_PTHREAD_H
#include <pthread.h>
#endif
#ifdef HAVE_SEMAPHORE_H
#include <semaphore.h>
#endif
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <assert.h>
#include "metadata/sgen-gc.h"
#include "metadata/metadata-internals.h"
#include "metadata/class-internals.h"
#include "metadata/gc-internal.h"
#include "metadata/object-internals.h"
#include "metadata/threads.h"
#include "metadata/sgen-cardtable.h"
#include "metadata/sgen-ssb.h"
#include "metadata/sgen-protocol.h"
#include "metadata/sgen-archdep.h"
#include "metadata/sgen-bridge.h"
#include "metadata/sgen-memory-governor.h"
#include "metadata/sgen-hash-table.h"
#include "metadata/mono-gc.h"
#include "metadata/method-builder.h"
#include "metadata/profiler-private.h"
#include "metadata/monitor.h"
#include "metadata/threadpool-internals.h"
#include "metadata/mempool-internals.h"
#include "metadata/marshal.h"
#include "metadata/runtime.h"
#include "metadata/sgen-cardtable.h"
#include "metadata/sgen-pinning.h"
#include "metadata/sgen-workers.h"
#include "utils/mono-mmap.h"
#include "utils/mono-time.h"
#include "utils/mono-semaphore.h"
#include "utils/mono-counters.h"
#include "utils/mono-proclib.h"
#include "utils/mono-memory-model.h"
#include "utils/mono-logger-internal.h"
#include "utils/dtrace.h"
#include <mono/utils/mono-logger-internal.h>
#include <mono/utils/memcheck.h>
#if defined(__MACH__)
#include "utils/mach-support.h"
#endif
#define OPDEF(a,b,c,d,e,f,g,h,i,j) \
a = i,
enum {
#include "mono/cil/opcode.def"
CEE_LAST
};
#undef OPDEF
#undef pthread_create
#undef pthread_join
#undef pthread_detach
/*
* ######################################################################
* ######## Types and constants used by the GC.
* ######################################################################
*/
/* 0 means not initialized, 1 is initialized, -1 means in progress */
static int gc_initialized = 0;
/* If set, check if we need to do something every X allocations */
gboolean has_per_allocation_action;
/* If set, do a heap check every X allocation */
guint32 verify_before_allocs = 0;
/* If set, do a minor collection before every X allocation */
guint32 collect_before_allocs = 0;
/* If set, do a whole heap check before each collection */
static gboolean whole_heap_check_before_collection = FALSE;
/* If set, do a heap consistency check before each minor collection */
static gboolean consistency_check_at_minor_collection = FALSE;
/* If set, check that there are no references to the domain left at domain unload */
static gboolean xdomain_checks = FALSE;
/* If not null, dump the heap after each collection into this file */
static FILE *heap_dump_file = NULL;
/* If set, mark stacks conservatively, even if precise marking is possible */
static gboolean conservative_stack_mark = FALSE;
/* If set, do a plausibility check on the scan_starts before and after
each collection */
static gboolean do_scan_starts_check = FALSE;
static gboolean nursery_collection_is_parallel = FALSE;
static gboolean disable_minor_collections = FALSE;
static gboolean disable_major_collections = FALSE;
gboolean do_pin_stats = FALSE;
static gboolean do_verify_nursery = FALSE;
static gboolean do_dump_nursery_content = FALSE;
#ifdef HEAVY_STATISTICS
long long stat_objects_alloced_degraded = 0;
long long stat_bytes_alloced_degraded = 0;
long long stat_copy_object_called_nursery = 0;
long long stat_objects_copied_nursery = 0;
long long stat_copy_object_called_major = 0;
long long stat_objects_copied_major = 0;
long long stat_scan_object_called_nursery = 0;
long long stat_scan_object_called_major = 0;
long long stat_slots_allocated_in_vain;
long long stat_nursery_copy_object_failed_from_space = 0;
long long stat_nursery_copy_object_failed_forwarded = 0;
long long stat_nursery_copy_object_failed_pinned = 0;
long long stat_nursery_copy_object_failed_to_space = 0;
static int stat_wbarrier_set_field = 0;
static int stat_wbarrier_set_arrayref = 0;
static int stat_wbarrier_arrayref_copy = 0;
static int stat_wbarrier_generic_store = 0;
static int stat_wbarrier_set_root = 0;
static int stat_wbarrier_value_copy = 0;
static int stat_wbarrier_object_copy = 0;
#endif
int stat_minor_gcs = 0;
int stat_major_gcs = 0;
static long long stat_pinned_objects = 0;
static long long time_minor_pre_collection_fragment_clear = 0;
static long long time_minor_pinning = 0;
static long long time_minor_scan_remsets = 0;
static long long time_minor_scan_pinned = 0;
static long long time_minor_scan_registered_roots = 0;
static long long time_minor_scan_thread_data = 0;
static long long time_minor_finish_gray_stack = 0;
static long long time_minor_fragment_creation = 0;
static long long time_major_pre_collection_fragment_clear = 0;
static long long time_major_pinning = 0;
static long long time_major_scan_pinned = 0;
static long long time_major_scan_registered_roots = 0;
static long long time_major_scan_thread_data = 0;
static long long time_major_scan_alloc_pinned = 0;
static long long time_major_scan_finalized = 0;
static long long time_major_scan_big_objects = 0;
static long long time_major_finish_gray_stack = 0;
static long long time_major_free_bigobjs = 0;
static long long time_major_los_sweep = 0;
static long long time_major_sweep = 0;
static long long time_major_fragment_creation = 0;
int gc_debug_level = 0;
FILE* gc_debug_file;
/*
void
mono_gc_flush_info (void)
{
fflush (gc_debug_file);
}
*/
#define TV_DECLARE SGEN_TV_DECLARE
#define TV_GETTIME SGEN_TV_GETTIME
#define TV_ELAPSED SGEN_TV_ELAPSED
#define TV_ELAPSED_MS SGEN_TV_ELAPSED_MS
#define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
NurseryClearPolicy nursery_clear_policy = CLEAR_AT_TLAB_CREATION;
/* the runtime can register areas of memory as roots: we keep two lists of roots,
* a pinned root set for conservatively scanned roots and a normal one for
* precisely scanned roots (currently implemented as a single list).
*/
typedef struct _RootRecord RootRecord;
struct _RootRecord {
char *end_root;
mword root_desc;
};
#define object_is_forwarded SGEN_OBJECT_IS_FORWARDED
#define object_is_pinned SGEN_OBJECT_IS_PINNED
#define pin_object SGEN_PIN_OBJECT
#define unpin_object SGEN_UNPIN_OBJECT
#define ptr_in_nursery sgen_ptr_in_nursery
#define LOAD_VTABLE SGEN_LOAD_VTABLE
static const char*
safe_name (void* obj)
{
MonoVTable *vt = (MonoVTable*)LOAD_VTABLE (obj);
return vt->klass->name;
}
#define safe_object_get_size sgen_safe_object_get_size
const char*
sgen_safe_name (void* obj)
{
return safe_name (obj);
}
/*
* ######################################################################
* ######## Global data.
* ######################################################################
*/
LOCK_DECLARE (gc_mutex);
static int gc_disabled = 0;
static gboolean use_cardtable;
#define SCAN_START_SIZE SGEN_SCAN_START_SIZE
static mword pagesize = 4096;
int degraded_mode = 0;
static mword bytes_pinned_from_failed_allocation = 0;
GCMemSection *nursery_section = NULL;
static mword lowest_heap_address = ~(mword)0;
static mword highest_heap_address = 0;
static LOCK_DECLARE (interruption_mutex);
static LOCK_DECLARE (pin_queue_mutex);
#define LOCK_PIN_QUEUE mono_mutex_lock (&pin_queue_mutex)
#define UNLOCK_PIN_QUEUE mono_mutex_unlock (&pin_queue_mutex)
typedef struct _FinalizeReadyEntry FinalizeReadyEntry;
struct _FinalizeReadyEntry {
FinalizeReadyEntry *next;
void *object;
};
typedef struct _EphemeronLinkNode EphemeronLinkNode;
struct _EphemeronLinkNode {
EphemeronLinkNode *next;
char *array;
};
typedef struct {
void *key;
void *value;
} Ephemeron;
int current_collection_generation = -1;
/*
* The link pointer is hidden by negating each bit. We use the lowest
* bit of the link (before negation) to store whether it needs
* resurrection tracking.
*/
#define HIDE_POINTER(p,t) ((gpointer)(~((gulong)(p)|((t)?1:0))))
#define REVEAL_POINTER(p) ((gpointer)((~(gulong)(p))&~3L))
/* objects that are ready to be finalized */
static FinalizeReadyEntry *fin_ready_list = NULL;
static FinalizeReadyEntry *critical_fin_list = NULL;
static EphemeronLinkNode *ephemeron_list;
static int num_ready_finalizers = 0;
static int no_finalize = 0;
enum {
ROOT_TYPE_NORMAL = 0, /* "normal" roots */
ROOT_TYPE_PINNED = 1, /* roots without a GC descriptor */
ROOT_TYPE_WBARRIER = 2, /* roots with a write barrier */
ROOT_TYPE_NUM
};
/* registered roots: the key to the hash is the root start address */
/*
* Different kinds of roots are kept separate to speed up pin_from_roots () for example.
*/
static SgenHashTable roots_hash [ROOT_TYPE_NUM] = {
SGEN_HASH_TABLE_INIT (INTERNAL_MEM_ROOTS_TABLE, INTERNAL_MEM_ROOT_RECORD, sizeof (RootRecord), mono_aligned_addr_hash, NULL),
SGEN_HASH_TABLE_INIT (INTERNAL_MEM_ROOTS_TABLE, INTERNAL_MEM_ROOT_RECORD, sizeof (RootRecord), mono_aligned_addr_hash, NULL),
SGEN_HASH_TABLE_INIT (INTERNAL_MEM_ROOTS_TABLE, INTERNAL_MEM_ROOT_RECORD, sizeof (RootRecord), mono_aligned_addr_hash, NULL)
};
static mword roots_size = 0; /* amount of memory in the root set */
#define GC_ROOT_NUM 32
typedef struct {
int count;
void *objects [GC_ROOT_NUM];
int root_types [GC_ROOT_NUM];
uintptr_t extra_info [GC_ROOT_NUM];
} GCRootReport;
static void
notify_gc_roots (GCRootReport *report)
{
if (!report->count)
return;
mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
report->count = 0;
}
static void
add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
{
if (report->count == GC_ROOT_NUM)
notify_gc_roots (report);
report->objects [report->count] = object;
report->root_types [report->count] = rtype;
report->extra_info [report->count++] = (uintptr_t)((MonoVTable*)LOAD_VTABLE (object))->klass;
}
MonoNativeTlsKey thread_info_key;
#ifdef HAVE_KW_THREAD
__thread SgenThreadInfo *thread_info;
__thread gpointer *store_remset_buffer;
__thread long store_remset_buffer_index;
__thread char *stack_end;
__thread long *store_remset_buffer_index_addr;
#endif
/* The size of a TLAB */
/* The bigger the value, the less often we have to go to the slow path to allocate a new
* one, but the more space is wasted by threads not allocating much memory.
* FIXME: Tune this.
* FIXME: Make this self-tuning for each thread.
*/
guint32 tlab_size = (1024 * 4);
#define MAX_SMALL_OBJ_SIZE SGEN_MAX_SMALL_OBJ_SIZE
/* Functions supplied by the runtime to be called by the GC */
static MonoGCCallbacks gc_callbacks;
#define ALLOC_ALIGN SGEN_ALLOC_ALIGN
#define ALLOC_ALIGN_BITS SGEN_ALLOC_ALIGN_BITS
#define ALIGN_UP SGEN_ALIGN_UP
#define MOVED_OBJECTS_NUM 64
static void *moved_objects [MOVED_OBJECTS_NUM];
static int moved_objects_idx = 0;
/* Vtable of the objects used to fill out nursery fragments before a collection */
static MonoVTable *array_fill_vtable;
#ifdef SGEN_DEBUG_INTERNAL_ALLOC
MonoNativeThreadId main_gc_thread = NULL;
#endif
/*Object was pinned during the current collection*/
static mword objects_pinned;
/*
* ######################################################################
* ######## Macros and function declarations.
* ######################################################################
*/
inline static void*
align_pointer (void *ptr)
{
mword p = (mword)ptr;
p += sizeof (gpointer) - 1;
p &= ~ (sizeof (gpointer) - 1);
return (void*)p;
}
typedef SgenGrayQueue GrayQueue;
/* forward declarations */
static int stop_world (int generation);
static int restart_world (int generation, GGTimingInfo *timing);
static void scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, GrayQueue *queue);
static void scan_from_registered_roots (CopyOrMarkObjectFunc copy_func, char *addr_start, char *addr_end, int root_type, GrayQueue *queue);
static void scan_finalizer_entries (CopyOrMarkObjectFunc copy_func, FinalizeReadyEntry *list, GrayQueue *queue);
static void report_finalizer_roots (void);
static void report_registered_roots (void);
static void find_pinning_ref_from_thread (char *obj, size_t size);
static void update_current_thread_stack (void *start);
static void collect_bridge_objects (CopyOrMarkObjectFunc copy_func, char *start, char *end, int generation, GrayQueue *queue);
static void finalize_in_range (CopyOrMarkObjectFunc copy_func, char *start, char *end, int generation, GrayQueue *queue);
static void process_fin_stage_entries (void);
static void null_link_in_range (CopyOrMarkObjectFunc copy_func, char *start, char *end, int generation, gboolean before_finalization, GrayQueue *queue);
static void null_links_for_domain (MonoDomain *domain, int generation);
static void remove_finalizers_for_domain (MonoDomain *domain, int generation);
static void process_dislink_stage_entries (void);
static void pin_from_roots (void *start_nursery, void *end_nursery, GrayQueue *queue);
static int pin_objects_from_addresses (GCMemSection *section, void **start, void **end, void *start_nursery, void *end_nursery, GrayQueue *queue);
static void finish_gray_stack (char *start_addr, char *end_addr, int generation, GrayQueue *queue);
static void mono_gc_register_disappearing_link (MonoObject *obj, void **link, gboolean track, gboolean in_gc);
static gboolean mono_gc_is_critical_method (MonoMethod *method);
void mono_gc_scan_for_specific_ref (MonoObject *key, gboolean precise);
static void init_stats (void);
static int mark_ephemerons_in_range (CopyOrMarkObjectFunc copy_func, char *start, char *end, GrayQueue *queue);
static void clear_unreachable_ephemerons (CopyOrMarkObjectFunc copy_func, char *start, char *end, GrayQueue *queue);
static void null_ephemerons_for_domain (MonoDomain *domain);
SgenObjectOperations current_object_ops;
SgenMajorCollector major_collector;
SgenMinorCollector sgen_minor_collector;
static GrayQueue gray_queue;
static SgenRemeberedSet remset;
#define WORKERS_DISTRIBUTE_GRAY_QUEUE (sgen_collection_is_parallel () ? sgen_workers_get_distribute_gray_queue () : &gray_queue)
static SgenGrayQueue*
sgen_workers_get_job_gray_queue (WorkerData *worker_data)
{
return worker_data ? &worker_data->private_gray_queue : WORKERS_DISTRIBUTE_GRAY_QUEUE;
}
static gboolean
is_xdomain_ref_allowed (gpointer *ptr, char *obj, MonoDomain *domain)
{
MonoObject *o = (MonoObject*)(obj);
MonoObject *ref = (MonoObject*)*(ptr);
int offset = (char*)(ptr) - (char*)o;
if (o->vtable->klass == mono_defaults.thread_class && offset == G_STRUCT_OFFSET (MonoThread, internal_thread))
return TRUE;
if (o->vtable->klass == mono_defaults.internal_thread_class && offset == G_STRUCT_OFFSET (MonoInternalThread, current_appcontext))
return TRUE;
if (mono_class_has_parent_fast (o->vtable->klass, mono_defaults.real_proxy_class) &&
offset == G_STRUCT_OFFSET (MonoRealProxy, unwrapped_server))
return TRUE;
/* Thread.cached_culture_info */
if (!strcmp (ref->vtable->klass->name_space, "System.Globalization") &&
!strcmp (ref->vtable->klass->name, "CultureInfo") &&
!strcmp(o->vtable->klass->name_space, "System") &&
!strcmp(o->vtable->klass->name, "Object[]"))
return TRUE;
/*
* at System.IO.MemoryStream.InternalConstructor (byte[],int,int,bool,bool) [0x0004d] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.IO/MemoryStream.cs:121
* at System.IO.MemoryStream..ctor (byte[]) [0x00017] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.IO/MemoryStream.cs:81
* at (wrapper remoting-invoke-with-check) System.IO.MemoryStream..ctor (byte[]) <IL 0x00020, 0xffffffff>
* at System.Runtime.Remoting.Messaging.CADMethodCallMessage.GetArguments () [0x0000d] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.Runtime.Remoting.Messaging/CADMessages.cs:327
* at System.Runtime.Remoting.Messaging.MethodCall..ctor (System.Runtime.Remoting.Messaging.CADMethodCallMessage) [0x00017] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.Runtime.Remoting.Messaging/MethodCall.cs:87
* at System.AppDomain.ProcessMessageInDomain (byte[],System.Runtime.Remoting.Messaging.CADMethodCallMessage,byte[]&,System.Runtime.Remoting.Messaging.CADMethodReturnMessage&) [0x00018] in /home/schani/Work/novell/trunk/mcs/class/corlib/System/AppDomain.cs:1213
* at (wrapper remoting-invoke-with-check) System.AppDomain.ProcessMessageInDomain (byte[],System.Runtime.Remoting.Messaging.CADMethodCallMessage,byte[]&,System.Runtime.Remoting.Messaging.CADMethodReturnMessage&) <IL 0x0003d, 0xffffffff>
* at System.Runtime.Remoting.Channels.CrossAppDomainSink.ProcessMessageInDomain (byte[],System.Runtime.Remoting.Messaging.CADMethodCallMessage) [0x00008] in /home/schani/Work/novell/trunk/mcs/class/corlib/System.Runtime.Remoting.Channels/CrossAppDomainChannel.cs:198
* at (wrapper runtime-invoke) object.runtime_invoke_CrossAppDomainSink/ProcessMessageRes_object_object (object,intptr,intptr,intptr) <IL 0x0004c, 0xffffffff>
*/
if (!strcmp (ref->vtable->klass->name_space, "System") &&
!strcmp (ref->vtable->klass->name, "Byte[]") &&
!strcmp (o->vtable->klass->name_space, "System.IO") &&
!strcmp (o->vtable->klass->name, "MemoryStream"))
return TRUE;
/* append_job() in threadpool.c */
if (!strcmp (ref->vtable->klass->name_space, "System.Runtime.Remoting.Messaging") &&
!strcmp (ref->vtable->klass->name, "AsyncResult") &&
!strcmp (o->vtable->klass->name_space, "System") &&
!strcmp (o->vtable->klass->name, "Object[]") &&
mono_thread_pool_is_queue_array ((MonoArray*) o))
return TRUE;
return FALSE;
}
static void
check_reference_for_xdomain (gpointer *ptr, char *obj, MonoDomain *domain)
{
MonoObject *o = (MonoObject*)(obj);
MonoObject *ref = (MonoObject*)*(ptr);
int offset = (char*)(ptr) - (char*)o;
MonoClass *class;
MonoClassField *field;
char *str;
if (!ref || ref->vtable->domain == domain)
return;
if (is_xdomain_ref_allowed (ptr, obj, domain))
return;
field = NULL;
for (class = o->vtable->klass; class; class = class->parent) {
int i;
for (i = 0; i < class->field.count; ++i) {
if (class->fields[i].offset == offset) {
field = &class->fields[i];
break;
}
}
if (field)
break;
}
if (ref->vtable->klass == mono_defaults.string_class)
str = mono_string_to_utf8 ((MonoString*)ref);
else
str = NULL;
g_print ("xdomain reference in %p (%s.%s) at offset %d (%s) to %p (%s.%s) (%s) - pointed to by:\n",
o, o->vtable->klass->name_space, o->vtable->klass->name,
offset, field ? field->name : "",
ref, ref->vtable->klass->name_space, ref->vtable->klass->name, str ? str : "");
mono_gc_scan_for_specific_ref (o, TRUE);
if (str)
g_free (str);
}
#undef HANDLE_PTR
#define HANDLE_PTR(ptr,obj) check_reference_for_xdomain ((ptr), (obj), domain)
static void
scan_object_for_xdomain_refs (char *start, mword size, void *data)
{
MonoDomain *domain = ((MonoObject*)start)->vtable->domain;
#include "sgen-scan-object.h"
}
static gboolean scan_object_for_specific_ref_precise = TRUE;
#undef HANDLE_PTR
#define HANDLE_PTR(ptr,obj) do { \
if ((MonoObject*)*(ptr) == key) { \
g_print ("found ref to %p in object %p (%s) at offset %td\n", \
key, (obj), safe_name ((obj)), ((char*)(ptr) - (char*)(obj))); \
} \
} while (0)
static void
scan_object_for_specific_ref (char *start, MonoObject *key)
{
char *forwarded;
if ((forwarded = SGEN_OBJECT_IS_FORWARDED (start)))
start = forwarded;
if (scan_object_for_specific_ref_precise) {
#include "sgen-scan-object.h"
} else {
mword *words = (mword*)start;
size_t size = safe_object_get_size ((MonoObject*)start);
int i;
for (i = 0; i < size / sizeof (mword); ++i) {
if (words [i] == (mword)key) {
g_print ("found possible ref to %p in object %p (%s) at offset %td\n",
key, start, safe_name (start), i * sizeof (mword));
}
}
}
}
void
sgen_scan_area_with_callback (char *start, char *end, IterateObjectCallbackFunc callback, void *data, gboolean allow_flags)
{
while (start < end) {
size_t size;
char *obj;
if (!*(void**)start) {
start += sizeof (void*); /* should be ALLOC_ALIGN, really */
continue;
}
if (allow_flags) {
if (!(obj = SGEN_OBJECT_IS_FORWARDED (start)))
obj = start;
} else {
obj = start;
}
size = ALIGN_UP (safe_object_get_size ((MonoObject*)obj));
if ((MonoVTable*)SGEN_LOAD_VTABLE (obj) != array_fill_vtable)
callback (obj, size, data);
start += size;
}
}
static void
scan_object_for_specific_ref_callback (char *obj, size_t size, MonoObject *key)
{
scan_object_for_specific_ref (obj, key);
}
static void
check_root_obj_specific_ref (RootRecord *root, MonoObject *key, MonoObject *obj)
{
if (key != obj)
return;
g_print ("found ref to %p in root record %p\n", key, root);
}
static MonoObject *check_key = NULL;
static RootRecord *check_root = NULL;
static void
check_root_obj_specific_ref_from_marker (void **obj)
{
check_root_obj_specific_ref (check_root, check_key, *obj);
}
static void
scan_roots_for_specific_ref (MonoObject *key, int root_type)
{
void **start_root;
RootRecord *root;
check_key = key;
SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], start_root, root) {
mword desc = root->root_desc;
check_root = root;
switch (desc & ROOT_DESC_TYPE_MASK) {
case ROOT_DESC_BITMAP:
desc >>= ROOT_DESC_TYPE_SHIFT;
while (desc) {
if (desc & 1)
check_root_obj_specific_ref (root, key, *start_root);
desc >>= 1;
start_root++;
}
return;
case ROOT_DESC_COMPLEX: {
gsize *bitmap_data = sgen_get_complex_descriptor_bitmap (desc);
int bwords = (*bitmap_data) - 1;
void **start_run = start_root;
bitmap_data++;
while (bwords-- > 0) {
gsize bmap = *bitmap_data++;
void **objptr = start_run;
while (bmap) {
if (bmap & 1)
check_root_obj_specific_ref (root, key, *objptr);
bmap >>= 1;
++objptr;
}
start_run += GC_BITS_PER_WORD;
}
break;
}
case ROOT_DESC_USER: {
MonoGCRootMarkFunc marker = sgen_get_user_descriptor_func (desc);
marker (start_root, check_root_obj_specific_ref_from_marker);
break;
}
case ROOT_DESC_RUN_LEN:
g_assert_not_reached ();
default:
g_assert_not_reached ();
}
} SGEN_HASH_TABLE_FOREACH_END;
check_key = NULL;
check_root = NULL;
}
void
mono_gc_scan_for_specific_ref (MonoObject *key, gboolean precise)
{
void **ptr;
RootRecord *root;
scan_object_for_specific_ref_precise = precise;
sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
(IterateObjectCallbackFunc)scan_object_for_specific_ref_callback, key, TRUE);
major_collector.iterate_objects (TRUE, TRUE, (IterateObjectCallbackFunc)scan_object_for_specific_ref_callback, key);
sgen_los_iterate_objects ((IterateObjectCallbackFunc)scan_object_for_specific_ref_callback, key);
scan_roots_for_specific_ref (key, ROOT_TYPE_NORMAL);
scan_roots_for_specific_ref (key, ROOT_TYPE_WBARRIER);
SGEN_HASH_TABLE_FOREACH (&roots_hash [ROOT_TYPE_PINNED], ptr, root) {
while (ptr < (void**)root->end_root) {
check_root_obj_specific_ref (root, *ptr, key);
++ptr;
}
} SGEN_HASH_TABLE_FOREACH_END;
}
static gboolean
need_remove_object_for_domain (char *start, MonoDomain *domain)
{
if (mono_object_domain (start) == domain) {
DEBUG (4, fprintf (gc_debug_file, "Need to cleanup object %p\n", start));
binary_protocol_cleanup (start, (gpointer)LOAD_VTABLE (start), safe_object_get_size ((MonoObject*)start));
return TRUE;
}
return FALSE;
}
static void
process_object_for_domain_clearing (char *start, MonoDomain *domain)
{
GCVTable *vt = (GCVTable*)LOAD_VTABLE (start);
if (vt->klass == mono_defaults.internal_thread_class)
g_assert (mono_object_domain (start) == mono_get_root_domain ());
/* The object could be a proxy for an object in the domain
we're deleting. */
if (mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
/* The server could already have been zeroed out, so
we need to check for that, too. */
if (server && (!LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
DEBUG (4, fprintf (gc_debug_file, "Cleaning up remote pointer in %p to object %p\n",
start, server));
((MonoRealProxy*)start)->unwrapped_server = NULL;
}
}
}
static MonoDomain *check_domain = NULL;
static void
check_obj_not_in_domain (void **o)
{
g_assert (((MonoObject*)(*o))->vtable->domain != check_domain);
}
static void
scan_for_registered_roots_in_domain (MonoDomain *domain, int root_type)
{
void **start_root;
RootRecord *root;
check_domain = domain;
SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], start_root, root) {
mword desc = root->root_desc;
/* The MonoDomain struct is allowed to hold
references to objects in its own domain. */
if (start_root == (void**)domain)
continue;
switch (desc & ROOT_DESC_TYPE_MASK) {
case ROOT_DESC_BITMAP:
desc >>= ROOT_DESC_TYPE_SHIFT;
while (desc) {
if ((desc & 1) && *start_root)
check_obj_not_in_domain (*start_root);
desc >>= 1;
start_root++;
}
break;
case ROOT_DESC_COMPLEX: {
gsize *bitmap_data = sgen_get_complex_descriptor_bitmap (desc);
int bwords = (*bitmap_data) - 1;
void **start_run = start_root;
bitmap_data++;
while (bwords-- > 0) {
gsize bmap = *bitmap_data++;
void **objptr = start_run;
while (bmap) {
if ((bmap & 1) && *objptr)
check_obj_not_in_domain (*objptr);
bmap >>= 1;
++objptr;
}
start_run += GC_BITS_PER_WORD;
}
break;
}
case ROOT_DESC_USER: {
MonoGCRootMarkFunc marker = sgen_get_user_descriptor_func (desc);
marker (start_root, check_obj_not_in_domain);
break;
}
case ROOT_DESC_RUN_LEN:
g_assert_not_reached ();
default:
g_assert_not_reached ();
}
} SGEN_HASH_TABLE_FOREACH_END;
check_domain = NULL;
}
static void
check_for_xdomain_refs (void)
{
LOSObject *bigobj;
sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
(IterateObjectCallbackFunc)scan_object_for_xdomain_refs, NULL, FALSE);
major_collector.iterate_objects (TRUE, TRUE, (IterateObjectCallbackFunc)scan_object_for_xdomain_refs, NULL);
for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
scan_object_for_xdomain_refs (bigobj->data, bigobj->size, NULL);
}
static gboolean