#include <mono/metadata/debug-helpers.h>
#include <mono/metadata/tabledefs.h>
#include <mono/metadata/marshal.h>
+#include <mono/utils/mono-threads.h>
#include <mono/metadata/profiler-private.h>
#include <mono/utils/mono-time.h>
#include <mono/utils/atomic.h>
*
* Bacon's thin locks have a fast path that doesn't need a lock record
* for the common case of locking an unlocked or shallow-nested
- * object, but the technique relies on encoding the thread ID in 15
- * bits (to avoid too much per-object space overhead.) Unfortunately
- * I don't think it's possible to reliably encode a pthread_t into 15
- * bits. (The JVM implementation used seems to have a 15-bit
- * per-thread identifier available.)
- *
- * This implementation then combines Dice's basic lock model with
- * Bacon's simplification of keeping a lock record for the lifetime of
- * an object.
+ * object.
*/
static MonitorArray *monitor_allocated;
static int array_size = 16;
-#ifdef HAVE_KW_THREAD
-static __thread gsize tls_pthread_self MONO_TLS_FAST;
-#endif
+/* MonoThreadsSync status helpers */
-#ifndef HOST_WIN32
-#ifdef HAVE_KW_THREAD
-#define GetCurrentThreadId() tls_pthread_self
-#else
-/*
- * The usual problem: we can't replace GetCurrentThreadId () with a macro because
- * it is in a public header.
- */
-#define GetCurrentThreadId() ((gsize)pthread_self ())
-#endif
-#endif
+static inline guint32
+mon_status_get_owner (guint32 status)
+{
+ return status & OWNER_MASK;
+}
+
+static inline guint32
+mon_status_set_owner (guint32 status, guint32 owner)
+{
+ return (status & ENTRY_COUNT_MASK) | owner;
+}
+
+static inline gint32
+mon_status_get_entry_count (guint32 status)
+{
+ gint32 entry_count = (gint32)((status & ENTRY_COUNT_MASK) >> ENTRY_COUNT_SHIFT);
+ gint32 zero = (gint32)(((guint32)ENTRY_COUNT_ZERO) >> ENTRY_COUNT_SHIFT);
+ return entry_count - zero;
+}
+
+static inline guint32
+mon_status_init_entry_count (guint32 status)
+{
+ return (status & OWNER_MASK) | ENTRY_COUNT_ZERO;
+}
+
+static inline guint32
+mon_status_increment_entry_count (guint32 status)
+{
+ return status + (1 << ENTRY_COUNT_SHIFT);
+}
+
+static inline guint32
+mon_status_decrement_entry_count (guint32 status)
+{
+ return status - (1 << ENTRY_COUNT_SHIFT);
+}
+
+static inline gboolean
+mon_status_have_waiters (guint32 status)
+{
+ return status & ENTRY_COUNT_WAITERS;
+}
+
+/* LockWord helpers */
+
+static inline MonoThreadsSync*
+lock_word_get_inflated_lock (LockWord lw)
+{
+ lw.lock_word &= (~LOCK_WORD_STATUS_MASK);
+ return lw.sync;
+}
+
+static inline gboolean
+lock_word_is_inflated (LockWord lw)
+{
+ return lw.lock_word & LOCK_WORD_INFLATED;
+}
+
+static inline gboolean
+lock_word_has_hash (LockWord lw)
+{
+ return lw.lock_word & LOCK_WORD_HAS_HASH;
+}
+
+static inline LockWord
+lock_word_set_has_hash (LockWord lw)
+{
+ LockWord nlw;
+ nlw.lock_word = lw.lock_word | LOCK_WORD_HAS_HASH;
+ return nlw;
+}
+
+static inline gboolean
+lock_word_is_free (LockWord lw)
+{
+ return !lw.lock_word;
+}
+
+static inline gboolean
+lock_word_is_flat (LockWord lw)
+{
+ /* Return whether the lock is flat or free */
+ return (lw.lock_word & LOCK_WORD_STATUS_MASK) == LOCK_WORD_FLAT;
+}
+
+static inline gint32
+lock_word_get_hash (LockWord lw)
+{
+ return (gint32) (lw.lock_word >> LOCK_WORD_HASH_SHIFT);
+}
+
+static inline gint32
+lock_word_get_nest (LockWord lw)
+{
+ if (lock_word_is_free (lw))
+ return 0;
+ /* Inword nest count starts from 0 */
+ return ((lw.lock_word & LOCK_WORD_NEST_MASK) >> LOCK_WORD_NEST_SHIFT) + 1;
+}
+
+static inline gboolean
+lock_word_is_nested (LockWord lw)
+{
+ return lw.lock_word & LOCK_WORD_NEST_MASK;
+}
+
+static inline gboolean
+lock_word_is_max_nest (LockWord lw)
+{
+ return (lw.lock_word & LOCK_WORD_NEST_MASK) == LOCK_WORD_NEST_MASK;
+}
+
+static inline LockWord
+lock_word_increment_nest (LockWord lw)
+{
+ lw.lock_word += 1 << LOCK_WORD_NEST_SHIFT;
+ return lw;
+}
+
+static inline LockWord
+lock_word_decrement_nest (LockWord lw)
+{
+ lw.lock_word -= 1 << LOCK_WORD_NEST_SHIFT;
+ return lw;
+}
+
+static inline gint32
+lock_word_get_owner (LockWord lw)
+{
+ return lw.lock_word >> LOCK_WORD_OWNER_SHIFT;
+}
+
+static inline LockWord
+lock_word_new_thin_hash (gint32 hash)
+{
+ LockWord lw;
+ lw.lock_word = (guint32)hash;
+ lw.lock_word = (lw.lock_word << LOCK_WORD_HASH_SHIFT) | LOCK_WORD_HAS_HASH;
+ return lw;
+}
+
+static inline LockWord
+lock_word_new_inflated (MonoThreadsSync *mon)
+{
+ LockWord lw;
+ lw.sync = mon;
+ lw.lock_word |= LOCK_WORD_INFLATED;
+ return lw;
+}
+
+static inline LockWord
+lock_word_new_flat (gint32 owner)
+{
+ LockWord lw;
+ lw.lock_word = owner;
+ lw.lock_word <<= LOCK_WORD_OWNER_SHIFT;
+ return lw;
+}
void
mono_monitor_init (void)
for (mon = monitor_freelist; mon; mon = mon->data)
mon->wait_list = (gpointer)-1;
- /* FIXME: This still crashes with sgen (async_read.exe) */
+ /*
+ * FIXME: This still crashes with sgen (async_read.exe)
+ *
+ * In mini_cleanup() we first call mono_runtime_cleanup(), which calls
+ * mono_monitor_cleanup(), which is supposed to free all monitor memory.
+ *
+ * Later in mini_cleanup(), we call mono_domain_free(), which calls
+ * mono_gc_clear_domain(), which frees all weak links associated with objects.
+ * Those weak links reside in the monitor structures, which we've freed earlier.
+ *
+ * Unless we fix this dependency in the shutdown sequence this code has to remain
+ * disabled, or at least the call to g_free().
+ */
/*
for (marray = monitor_allocated; marray; marray = next) {
int i;
*/
}
-/*
- * mono_monitor_init_tls:
- *
- * Setup TLS variables used by the monitor code for the current thread.
- */
-void
-mono_monitor_init_tls (void)
-{
-#if !defined(HOST_WIN32) && defined(HAVE_KW_THREAD)
- tls_pthread_self = (gsize) pthread_self ();
-#endif
-}
-
static int
monitor_is_on_freelist (MonoThreadsSync *mon)
{
to_recycle++;
} else {
if (!monitor_is_on_freelist (mon->data)) {
- MonoObject *holder = mono_gc_weak_link_get (&mon->data);
- if (mon->owner) {
- g_print ("Lock %p in object %p held by thread %p, nest level: %d\n",
- mon, holder, (void*)mon->owner, mon->nest);
+ MonoObject *holder = (MonoObject *)mono_gchandle_get_target ((guint32)mon->data);
+ if (mon_status_get_owner (mon->status)) {
+ g_print ("Lock %p in object %p held by thread %d, nest level: %d\n",
+ mon, holder, mon_status_get_owner (mon->status), mon->nest);
if (mon->entry_sem)
- g_print ("\tWaiting on semaphore %p: %d\n", mon->entry_sem, mon->entry_count);
+ g_print ("\tWaiting on semaphore %p: %d\n", mon->entry_sem, mon_status_get_entry_count (mon->status));
} else if (include_untaken) {
g_print ("Lock %p in object %p untaken\n", mon, holder);
}
*/
g_assert (mon->wait_list == NULL);
- mon->entry_count = 0;
/* owner and nest are set in mon_new, no need to zero them out */
mon->data = monitor_freelist;
new = NULL;
for (marray = monitor_allocated; marray; marray = marray->next) {
for (i = 0; i < marray->num_monitors; ++i) {
- if (marray->monitors [i].data == NULL) {
+ if (mono_gchandle_get_target ((guint32)marray->monitors [i].data) == NULL) {
new = &marray->monitors [i];
if (new->wait_list) {
/* Orphaned events left by aborted threads */
while (new->wait_list) {
- LOCK_DEBUG (g_message (G_GNUC_PRETTY_FUNCTION ": (%d): Closing orphaned event %d", GetCurrentThreadId (), new->wait_list->data));
+ LOCK_DEBUG (g_message (G_GNUC_PRETTY_FUNCTION ": (%d): Closing orphaned event %d", mono_thread_info_get_small_id (), new->wait_list->data));
CloseHandle (new->wait_list->data);
new->wait_list = g_slist_remove (new->wait_list, new->wait_list->data);
}
}
- mono_gc_weak_link_remove (&new->data, TRUE);
+ mono_gchandle_free ((guint32)new->data);
new->data = monitor_freelist;
monitor_freelist = new;
}
new = monitor_freelist;
monitor_freelist = new->data;
- new->owner = id;
+ new->status = mon_status_set_owner (0, id);
+ new->status = mon_status_init_entry_count (new->status);
new->nest = 1;
new->data = NULL;
return new;
}
-/*
- * Format of the lock word:
- * thinhash | fathash | data
- *
- * thinhash is the lower bit: if set data is the shifted hashcode of the object.
- * fathash is another bit: if set the hash code is stored in the MonoThreadsSync
- * struct pointed to by data
- * if neither bit is set and data is non-NULL, data is a MonoThreadsSync
- */
-typedef union {
- gsize lock_word;
- MonoThreadsSync *sync;
-} LockWord;
+static MonoThreadsSync*
+alloc_mon (MonoObject *obj, gint32 id)
+{
+ MonoThreadsSync *mon;
-enum {
- LOCK_WORD_THIN_HASH = 1,
- LOCK_WORD_FAT_HASH = 1 << 1,
- LOCK_WORD_BITS_MASK = 0x3,
- LOCK_WORD_HASH_SHIFT = 2
-};
+ mono_monitor_allocator_lock ();
+ mon = mon_new (id);
+ mon->data = (void *)(size_t)mono_gchandle_new_weakref (obj, TRUE);
+ mono_monitor_allocator_unlock ();
+
+ return mon;
+}
+
+
+static void
+discard_mon (MonoThreadsSync *mon)
+{
+ mono_monitor_allocator_lock ();
+ mono_gchandle_free ((guint32)mon->data);
+ mon_finalize (mon);
+ mono_monitor_allocator_unlock ();
+}
+
+static void
+mono_monitor_inflate_owned (MonoObject *obj, int id)
+{
+ MonoThreadsSync *mon;
+ LockWord nlw, old_lw, tmp_lw;
+ guint32 nest;
+
+ old_lw.sync = obj->synchronisation;
+ LOCK_DEBUG (g_message ("%s: (%d) Inflating owned lock object %p; LW = %p", __func__, id, obj, old_lw.sync));
+
+ if (lock_word_is_inflated (old_lw)) {
+ /* Someone else inflated the lock in the meantime */
+ return;
+ }
+
+ mon = alloc_mon (obj, id);
+
+ nest = lock_word_get_nest (old_lw);
+ mon->nest = nest;
+
+ nlw = lock_word_new_inflated (mon);
+
+ mono_memory_write_barrier ();
+ tmp_lw.sync = InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, nlw.sync, old_lw.sync);
+ if (tmp_lw.sync != old_lw.sync) {
+ /* Someone else inflated the lock in the meantime */
+ discard_mon (mon);
+ }
+}
+
+static void
+mono_monitor_inflate (MonoObject *obj)
+{
+ MonoThreadsSync *mon;
+ LockWord nlw, old_lw;
+
+ LOCK_DEBUG (g_message ("%s: (%d) Inflating lock object %p; LW = %p", __func__, mono_thread_info_get_small_id (), obj, obj->synchronisation));
+
+ mon = alloc_mon (obj, 0);
+
+ nlw = lock_word_new_inflated (mon);
+
+ old_lw.sync = obj->synchronisation;
+
+ for (;;) {
+ LockWord tmp_lw;
+
+ if (lock_word_is_inflated (old_lw)) {
+ break;
+ }
+#ifdef HAVE_MOVING_COLLECTOR
+ else if (lock_word_has_hash (old_lw)) {
+ mon->hash_code = lock_word_get_hash (old_lw);
+ mon->status = mon_status_set_owner (mon->status, 0);
+ nlw = lock_word_set_has_hash (nlw);
+ }
+#endif
+ else if (lock_word_is_free (old_lw)) {
+ mon->status = mon_status_set_owner (mon->status, 0);
+ mon->nest = 1;
+ } else {
+ /* Lock is flat */
+ mon->status = mon_status_set_owner (mon->status, lock_word_get_owner (old_lw));
+ mon->nest = lock_word_get_nest (old_lw);
+ }
+ mono_memory_write_barrier ();
+ tmp_lw.sync = InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, nlw.sync, old_lw.sync);
+ if (tmp_lw.sync == old_lw.sync) {
+ /* Successfully inflated the lock */
+ return;
+ }
+
+ old_lw.sync = tmp_lw.sync;
+ }
+
+ /* Someone else inflated the lock before us */
+ discard_mon (mon);
+}
#define MONO_OBJECT_ALIGNMENT_SHIFT 3
if (!obj)
return 0;
lw.sync = obj->synchronisation;
- if (lw.lock_word & LOCK_WORD_THIN_HASH) {
- /*g_print ("fast thin hash %d for obj %p store\n", (unsigned int)lw.lock_word >> LOCK_WORD_HASH_SHIFT, obj);*/
- return (unsigned int)lw.lock_word >> LOCK_WORD_HASH_SHIFT;
- }
- if (lw.lock_word & LOCK_WORD_FAT_HASH) {
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- /*g_print ("fast fat hash %d for obj %p store\n", lw.sync->hash_code, obj);*/
- return lw.sync->hash_code;
+
+ LOCK_DEBUG (g_message("%s: (%d) Get hash for object %p; LW = %p", __func__, mono_thread_info_get_small_id (), obj, obj->synchronisation));
+
+ if (lock_word_has_hash (lw)) {
+ if (lock_word_is_inflated (lw)) {
+ return lock_word_get_inflated_lock (lw)->hash_code;
+ } else {
+ return lock_word_get_hash (lw);
+ }
}
/*
* while we are inside this function, the GC will keep this object pinned,
* with the same value.
*/
hash = (GPOINTER_TO_UINT (obj) >> MONO_OBJECT_ALIGNMENT_SHIFT) * 2654435761u;
+#if SIZEOF_VOID_P == 4
/* clear the top bits as they can be discarded */
- hash &= ~(LOCK_WORD_BITS_MASK << 30);
- /* no hash flags were set, so it must be a MonoThreadsSync pointer if not NULL */
- if (lw.sync) {
- lw.sync->hash_code = hash;
- /*g_print ("storing hash code %d for obj %p in sync %p\n", hash, obj, lw.sync);*/
- lw.lock_word |= LOCK_WORD_FAT_HASH;
- /* this is safe since we don't deflate locks */
- obj->synchronisation = lw.sync;
- } else {
- /*g_print ("storing thin hash code %d for obj %p\n", hash, obj);*/
- lw.lock_word = LOCK_WORD_THIN_HASH | (hash << LOCK_WORD_HASH_SHIFT);
- if (InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, lw.sync, NULL) == NULL)
+ hash &= ~(LOCK_WORD_STATUS_MASK << (32 - LOCK_WORD_STATUS_BITS));
+#endif
+ if (lock_word_is_free (lw)) {
+ LockWord old_lw;
+ lw = lock_word_new_thin_hash (hash);
+
+ old_lw.sync = InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, lw.sync, NULL);
+ if (old_lw.sync == NULL) {
return hash;
- /*g_print ("failed store\n");*/
- /* someone set the hash flag or someone inflated the object */
- lw.sync = obj->synchronisation;
- if (lw.lock_word & LOCK_WORD_THIN_HASH)
+ }
+
+ if (lock_word_has_hash (old_lw)) {
+ /* Done by somebody else */
return hash;
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- lw.sync->hash_code = hash;
- lw.lock_word |= LOCK_WORD_FAT_HASH;
- /* this is safe since we don't deflate locks */
- obj->synchronisation = lw.sync;
+ }
+
+ mono_monitor_inflate (obj);
+ lw.sync = obj->synchronisation;
+ } else if (lock_word_is_flat (lw)) {
+ int id = mono_thread_info_get_small_id ();
+ if (lock_word_get_owner (lw) == id)
+ mono_monitor_inflate_owned (obj, id);
+ else
+ mono_monitor_inflate (obj);
+ lw.sync = obj->synchronisation;
}
+
+ /* At this point, the lock is inflated */
+ lock_word_get_inflated_lock (lw)->hash_code = hash;
+ lw = lock_word_set_has_hash (lw);
+ mono_memory_write_barrier ();
+ obj->synchronisation = lw.sync;
return hash;
#else
/*
#endif
}
+static void
+mono_monitor_ensure_owned (LockWord lw, guint32 id)
+{
+ if (lock_word_is_flat (lw)) {
+ if (lock_word_get_owner (lw) == id)
+ return;
+ } else if (lock_word_is_inflated (lw)) {
+ if (mon_status_get_owner (lock_word_get_inflated_lock (lw)->status) == id)
+ return;
+ }
+
+ mono_set_pending_exception (mono_get_exception_synchronization_lock ("Object synchronization method was called from an unsynchronized block of code."));
+}
+
+/*
+ * When this function is called it has already been established that the
+ * current thread owns the monitor.
+ */
+static void
+mono_monitor_exit_inflated (MonoObject *obj)
+{
+ LockWord lw;
+ MonoThreadsSync *mon;
+ guint32 nest;
+
+ lw.sync = obj->synchronisation;
+ mon = lock_word_get_inflated_lock (lw);
+
+ nest = mon->nest - 1;
+ if (nest == 0) {
+ guint32 new_status, old_status, tmp_status;
+
+ old_status = mon->status;
+
+ /*
+ * Release lock and do the wakeup stuff. It's possible that
+ * the last blocking thread gave up waiting just before we
+ * release the semaphore resulting in a negative entry count
+ * and a futile wakeup next time there's contention for this
+ * object.
+ */
+ for (;;) {
+ gboolean have_waiters = mon_status_have_waiters (old_status);
+
+ new_status = mon_status_set_owner (old_status, 0);
+ if (have_waiters)
+ new_status = mon_status_decrement_entry_count (new_status);
+ tmp_status = InterlockedCompareExchange ((gint32*)&mon->status, new_status, old_status);
+ if (tmp_status == old_status) {
+ if (have_waiters)
+ ReleaseSemaphore (mon->entry_sem, 1, NULL);
+ break;
+ }
+ old_status = tmp_status;
+ }
+ LOCK_DEBUG (g_message ("%s: (%d) Object %p is now unlocked", __func__, mono_thread_info_get_small_id (), obj));
+
+ /* object is now unlocked, leave nest==1 so we don't
+ * need to set it when the lock is reacquired
+ */
+ } else {
+ LOCK_DEBUG (g_message ("%s: (%d) Object %p is now locked %d times", __func__, mono_thread_info_get_small_id (), obj, nest));
+ mon->nest = nest;
+ }
+}
+
+/*
+ * When this function is called it has already been established that the
+ * current thread owns the monitor.
+ */
+static void
+mono_monitor_exit_flat (MonoObject *obj, LockWord old_lw)
+{
+ LockWord new_lw, tmp_lw;
+ if (G_UNLIKELY (lock_word_is_nested (old_lw)))
+ new_lw = lock_word_decrement_nest (old_lw);
+ else
+ new_lw.lock_word = 0;
+
+ tmp_lw.sync = InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, new_lw.sync, old_lw.sync);
+ if (old_lw.sync != tmp_lw.sync) {
+ /* Someone inflated the lock in the meantime */
+ mono_monitor_exit_inflated (obj);
+ }
+
+ LOCK_DEBUG (g_message ("%s: (%d) Object %p is now locked %d times; LW = %p", __func__, mono_thread_info_get_small_id (), obj, lock_word_get_nest (new_lw), obj->synchronisation));
+}
+
+static void
+mon_decrement_entry_count (MonoThreadsSync *mon)
+{
+ guint32 old_status, tmp_status, new_status;
+
+ /* Decrement entry count */
+ old_status = mon->status;
+ for (;;) {
+ new_status = mon_status_decrement_entry_count (old_status);
+ tmp_status = InterlockedCompareExchange ((gint32*)&mon->status, new_status, old_status);
+ if (tmp_status == old_status) {
+ break;
+ }
+ old_status = tmp_status;
+ }
+}
+
/* If allow_interruption==TRUE, the method will be interrumped if abort or suspend
* is requested. In this case it returns -1.
*/
static inline gint32
-mono_monitor_try_enter_internal (MonoObject *obj, guint32 ms, gboolean allow_interruption)
+mono_monitor_try_enter_inflated (MonoObject *obj, guint32 ms, gboolean allow_interruption, guint32 id)
{
+ LockWord lw;
MonoThreadsSync *mon;
- gsize id = GetCurrentThreadId ();
HANDLE sem;
guint32 then = 0, now, delta;
guint32 waitms;
guint32 ret;
+ guint32 new_status, old_status, tmp_status;
MonoInternalThread *thread;
+ gboolean interrupted = FALSE;
LOCK_DEBUG (g_message("%s: (%d) Trying to lock object %p (%d ms)", __func__, id, obj, ms));
if (G_UNLIKELY (!obj)) {
- mono_raise_exception (mono_get_exception_argument_null ("obj"));
+ mono_set_pending_exception (mono_get_exception_argument_null ("obj"));
return FALSE;
}
+ lw.sync = obj->synchronisation;
+ mon = lock_word_get_inflated_lock (lw);
retry:
- mon = obj->synchronisation;
-
- /* If the object has never been locked... */
- if (G_UNLIKELY (mon == NULL)) {
- mono_monitor_allocator_lock ();
- mon = mon_new (id);
- if (InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, mon, NULL) == NULL) {
- mono_gc_weak_link_add (&mon->data, obj, TRUE);
- mono_monitor_allocator_unlock ();
- /* Successfully locked */
- return 1;
- } else {
-#ifdef HAVE_MOVING_COLLECTOR
- LockWord lw;
- lw.sync = obj->synchronisation;
- if (lw.lock_word & LOCK_WORD_THIN_HASH) {
- MonoThreadsSync *oldlw = lw.sync;
- /* move the already calculated hash */
- mon->hash_code = lw.lock_word >> LOCK_WORD_HASH_SHIFT;
- lw.sync = mon;
- lw.lock_word |= LOCK_WORD_FAT_HASH;
- if (InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, lw.sync, oldlw) == oldlw) {
- mono_gc_weak_link_add (&mon->data, obj, TRUE);
- mono_monitor_allocator_unlock ();
- /* Successfully locked */
- return 1;
- } else {
- mon_finalize (mon);
- mono_monitor_allocator_unlock ();
- goto retry;
- }
- } else if (lw.lock_word & LOCK_WORD_FAT_HASH) {
- mon_finalize (mon);
- mono_monitor_allocator_unlock ();
- /* get the old lock without the fat hash bit */
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- } else {
- mon_finalize (mon);
- mono_monitor_allocator_unlock ();
- mon = obj->synchronisation;
- }
-#else
- mon_finalize (mon);
- mono_monitor_allocator_unlock ();
- mon = obj->synchronisation;
-#endif
- }
- } else {
-#ifdef HAVE_MOVING_COLLECTOR
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH) {
- MonoThreadsSync *oldlw = lw.sync;
- mono_monitor_allocator_lock ();
- mon = mon_new (id);
- /* move the already calculated hash */
- mon->hash_code = lw.lock_word >> LOCK_WORD_HASH_SHIFT;
- lw.sync = mon;
- lw.lock_word |= LOCK_WORD_FAT_HASH;
- if (InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, lw.sync, oldlw) == oldlw) {
- mono_gc_weak_link_add (&mon->data, obj, TRUE);
- mono_monitor_allocator_unlock ();
- /* Successfully locked */
- return 1;
- } else {
- mon_finalize (mon);
- mono_monitor_allocator_unlock ();
- goto retry;
- }
- }
-#endif
- }
-
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
-
- /* If the object has previously been locked but isn't now... */
-
/* This case differs from Dice's case 3 because we don't
* deflate locks or cache unused lock records
*/
- if (G_LIKELY (mon->owner == 0)) {
+ old_status = mon->status;
+ if (G_LIKELY (mon_status_get_owner (old_status) == 0)) {
/* Try to install our ID in the owner field, nest
- * should have been left at 1 by the previous unlock
- * operation
- */
- if (G_LIKELY (InterlockedCompareExchangePointer ((gpointer *)&mon->owner, (gpointer)id, 0) == 0)) {
+ * should have been left at 1 by the previous unlock
+ * operation
+ */
+ new_status = mon_status_set_owner (old_status, id);
+ tmp_status = InterlockedCompareExchange ((gint32*)&mon->status, new_status, old_status);
+ if (G_LIKELY (tmp_status == old_status)) {
/* Success */
g_assert (mon->nest == 1);
return 1;
}
/* If the object is currently locked by this thread... */
- if (mon->owner == id) {
+ if (mon_status_get_owner (old_status) == id) {
mon->nest++;
return 1;
}
/* This case differs from Dice's case 3 because we don't
* deflate locks or cache unused lock records
*/
- if (G_LIKELY (mon->owner == 0)) {
+ old_status = mon->status;
+ if (G_LIKELY (mon_status_get_owner (old_status) == 0)) {
/* Try to install our ID in the owner field, nest
* should have been left at 1 by the previous unlock
* operation
*/
- if (G_LIKELY (InterlockedCompareExchangePointer ((gpointer *)&mon->owner, (gpointer)id, 0) == 0)) {
+ new_status = mon_status_set_owner (old_status, id);
+ tmp_status = InterlockedCompareExchange ((gint32*)&mon->status, new_status, old_status);
+ if (G_LIKELY (tmp_status == old_status)) {
/* Success */
g_assert (mon->nest == 1);
mono_profiler_monitor_event (obj, MONO_PROFILER_MONITOR_DONE);
}
/* If the object is currently locked by this thread... */
- if (mon->owner == id) {
+ if (mon_status_get_owner (old_status) == id) {
mon->nest++;
mono_profiler_monitor_event (obj, MONO_PROFILER_MONITOR_DONE);
return 1;
CloseHandle (sem);
}
}
-
- /* If we need to time out, record a timestamp and adjust ms,
- * because WaitForSingleObject doesn't tell us how long it
- * waited for.
- *
- * Don't block forever here, because theres a chance the owner
- * thread released the lock while we were creating the
- * semaphore: we would not get the wakeup. Using the event
- * handle technique from pulse/wait would involve locking the
- * lock struct and therefore slowing down the fast path.
+
+ /*
+ * We need to register ourselves as waiting if it is the first time we are waiting,
+ * of if we were signaled and failed to acquire the lock.
*/
+ if (!interrupted) {
+ old_status = mon->status;
+ for (;;) {
+ if (mon_status_get_owner (old_status) == 0)
+ goto retry_contended;
+ new_status = mon_status_increment_entry_count (old_status);
+ tmp_status = InterlockedCompareExchange ((gint32*)&mon->status, new_status, old_status);
+ if (tmp_status == old_status) {
+ break;
+ }
+ old_status = tmp_status;
+ }
+ }
+
if (ms != INFINITE) {
then = mono_msec_ticks ();
- if (ms < 100) {
- waitms = ms;
- } else {
- waitms = 100;
- }
- } else {
- waitms = 100;
}
+ waitms = ms;
- InterlockedIncrement (&mon->entry_count);
-
#ifndef DISABLE_PERFCOUNTERS
mono_perfcounters->thread_queue_len++;
mono_perfcounters->thread_queue_max++;
* We pass TRUE instead of allow_interruption since we have to check for the
* StopRequested case below.
*/
+ MONO_PREPARE_BLOCKING;
ret = WaitForSingleObjectEx (mon->entry_sem, waitms, TRUE);
+ MONO_FINISH_BLOCKING;
mono_thread_clr_state (thread, ThreadState_WaitSleepJoin);
- InterlockedDecrement (&mon->entry_count);
#ifndef DISABLE_PERFCOUNTERS
mono_perfcounters->thread_queue_len--;
#endif
- if (ms != INFINITE) {
- now = mono_msec_ticks ();
-
- if (now < then) {
- /* The counter must have wrapped around */
- LOCK_DEBUG (g_message ("%s: wrapped around! now=0x%x then=0x%x", __func__, now, then));
-
- now += (0xffffffff - then);
- then = 0;
+ if (ret == WAIT_IO_COMPLETION && !allow_interruption) {
+ interrupted = TRUE;
+ /*
+ * We have to obey a stop/suspend request even if
+ * allow_interruption is FALSE to avoid hangs at shutdown.
+ */
+ if (!mono_thread_test_state (mono_thread_internal_current (), (ThreadState_StopRequested|ThreadState_SuspendRequested))) {
+ if (ms != INFINITE) {
+ now = mono_msec_ticks ();
+ if (now < then) {
+ LOCK_DEBUG (g_message ("%s: wrapped around! now=0x%x then=0x%x", __func__, now, then));
- LOCK_DEBUG (g_message ("%s: wrap rejig: now=0x%x then=0x%x delta=0x%x", __func__, now, then, now-then));
- }
-
- delta = now - then;
- if (delta >= ms) {
- ms = 0;
- } else {
- ms -= delta;
- }
+ now += (0xffffffff - then);
+ then = 0;
- if ((ret == WAIT_TIMEOUT || (ret == WAIT_IO_COMPLETION && !allow_interruption)) && ms > 0) {
- /* More time left */
- goto retry_contended;
- }
- } else {
- if (ret == WAIT_TIMEOUT || (ret == WAIT_IO_COMPLETION && !allow_interruption)) {
- if (ret == WAIT_IO_COMPLETION && (mono_thread_test_state (mono_thread_internal_current (), (ThreadState_StopRequested|ThreadState_SuspendRequested)))) {
- /*
- * We have to obey a stop/suspend request even if
- * allow_interruption is FALSE to avoid hangs at shutdown.
- */
- mono_profiler_monitor_event (obj, MONO_PROFILER_MONITOR_FAIL);
- return -1;
+ LOCK_DEBUG (g_message ("%s: wrap rejig: now=0x%x then=0x%x delta=0x%x", __func__, now, then, now-then));
+ }
+
+ delta = now - then;
+ if (delta >= ms) {
+ ms = 0;
+ } else {
+ ms -= delta;
+ }
}
- /* Infinite wait, so just try again */
+ /* retry from the top */
goto retry_contended;
}
- }
-
- if (ret == WAIT_OBJECT_0) {
+ } else if (ret == WAIT_OBJECT_0) {
+ interrupted = FALSE;
/* retry from the top */
goto retry_contended;
+ } else if (ret == WAIT_TIMEOUT) {
+ /* we're done */
}
- /* We must have timed out */
- LOCK_DEBUG (g_message ("%s: (%d) timed out waiting, returning FALSE", __func__, id));
+ /* Timed out or interrupted */
+ mon_decrement_entry_count (mon);
mono_profiler_monitor_event (obj, MONO_PROFILER_MONITOR_FAIL);
- if (ret == WAIT_IO_COMPLETION)
+ if (ret == WAIT_IO_COMPLETION) {
+ LOCK_DEBUG (g_message ("%s: (%d) interrupted waiting, returning -1", __func__, id));
return -1;
- else
+ } else if (ret == WAIT_TIMEOUT) {
+ LOCK_DEBUG (g_message ("%s: (%d) timed out waiting, returning FALSE", __func__, id));
return 0;
-}
-
-gboolean
-mono_monitor_enter (MonoObject *obj)
-{
- return mono_monitor_try_enter_internal (obj, INFINITE, FALSE) == 1;
-}
-
-gboolean
-mono_monitor_try_enter (MonoObject *obj, guint32 ms)
-{
- return mono_monitor_try_enter_internal (obj, ms, FALSE) == 1;
-}
-
-void
-mono_monitor_exit (MonoObject *obj)
-{
- MonoThreadsSync *mon;
- guint32 nest;
-
- LOCK_DEBUG (g_message ("%s: (%d) Unlocking %p", __func__, GetCurrentThreadId (), obj));
-
- if (G_UNLIKELY (!obj)) {
- mono_raise_exception (mono_get_exception_argument_null ("obj"));
- return;
- }
-
- mon = obj->synchronisation;
-
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH)
- return;
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
- if (G_UNLIKELY (mon == NULL)) {
- /* No one ever used Enter. Just ignore the Exit request as MS does */
- return;
- }
- if (G_UNLIKELY (mon->owner != GetCurrentThreadId ())) {
- return;
- }
-
- nest = mon->nest - 1;
- if (nest == 0) {
- LOCK_DEBUG (g_message ("%s: (%d) Object %p is now unlocked", __func__, GetCurrentThreadId (), obj));
-
- /* object is now unlocked, leave nest==1 so we don't
- * need to set it when the lock is reacquired
- */
- mon->owner = 0;
-
- /* Do the wakeup stuff. It's possible that the last
- * blocking thread gave up waiting just before we
- * release the semaphore resulting in a futile wakeup
- * next time there's contention for this object, but
- * it means we don't have to waste time locking the
- * struct.
- */
- if (mon->entry_count > 0) {
- ReleaseSemaphore (mon->entry_sem, 1, NULL);
- }
} else {
- LOCK_DEBUG (g_message ("%s: (%d) Object %p is now locked %d times", __func__, GetCurrentThreadId (), obj, nest));
- mon->nest = nest;
+ g_assert_not_reached ();
+ return 0;
}
}
-void**
-mono_monitor_get_object_monitor_weak_link (MonoObject *object)
+/*
+ * If allow_interruption == TRUE, the method will be interrupted if abort or suspend
+ * is requested. In this case it returns -1.
+ */
+static inline gint32
+mono_monitor_try_enter_internal (MonoObject *obj, guint32 ms, gboolean allow_interruption)
{
LockWord lw;
- MonoThreadsSync *sync = NULL;
-
- lw.sync = object->synchronisation;
- if (lw.lock_word & LOCK_WORD_FAT_HASH) {
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- sync = lw.sync;
- } else if (!(lw.lock_word & LOCK_WORD_THIN_HASH)) {
- sync = lw.sync;
- }
+ int id = mono_thread_info_get_small_id ();
- if (sync && sync->data)
- return &sync->data;
- return NULL;
-}
-
-#ifndef DISABLE_JIT
-
-static void
-emit_obj_syncp_check (MonoMethodBuilder *mb, int syncp_loc, int *obj_null_branch, int *true_locktaken_branch, int *syncp_true_false_branch,
- int *thin_hash_branch, gboolean branch_on_true)
-{
- /*
- ldarg 0 obj
- brfalse.s obj_null
- */
-
- mono_mb_emit_byte (mb, CEE_LDARG_0);
- *obj_null_branch = mono_mb_emit_short_branch (mb, CEE_BRFALSE_S);
+ LOCK_DEBUG (g_message("%s: (%d) Trying to lock object %p (%d ms)", __func__, id, obj, ms));
- /*
- ldarg.1
- ldind.i1
- brtrue.s true_locktaken
- */
- if (true_locktaken_branch) {
- mono_mb_emit_byte (mb, CEE_LDARG_1);
- mono_mb_emit_byte (mb, CEE_LDIND_I1);
- *true_locktaken_branch = mono_mb_emit_short_branch (mb, CEE_BRTRUE_S);
+ if (G_UNLIKELY (!obj)) {
+ mono_set_pending_exception (mono_get_exception_argument_null ("obj"));
+ return FALSE;
}
- /*
- ldarg 0 obj
- conv.i objp
- ldc.i4 MONO_STRUCT_OFFSET(MonoObject, synchronisation) objp off
- add &syncp
- ldind.i syncp
- stloc syncp
- ldloc syncp syncp
- brtrue/false.s syncp_true_false
- */
-
- mono_mb_emit_byte (mb, CEE_LDARG_0);
- mono_mb_emit_byte (mb, CEE_CONV_I);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoObject, synchronisation));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDIND_I);
- mono_mb_emit_stloc (mb, syncp_loc);
+ lw.sync = obj->synchronisation;
-
- if (mono_gc_is_moving ()) {
- /*check for a thin hash*/
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, 0x01);
- mono_mb_emit_byte (mb, CEE_CONV_I);
- mono_mb_emit_byte (mb, CEE_AND);
- *thin_hash_branch = mono_mb_emit_short_branch (mb, CEE_BRTRUE_S);
-
- /*clear gc bits*/
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, ~0x3);
- mono_mb_emit_byte (mb, CEE_CONV_I);
- mono_mb_emit_byte (mb, CEE_AND);
- mono_mb_emit_stloc (mb, syncp_loc);
- } else {
- *thin_hash_branch = 0;
+ if (G_LIKELY (lock_word_is_free (lw))) {
+ LockWord nlw = lock_word_new_flat (id);
+ if (InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, nlw.sync, NULL) == NULL) {
+ return 1;
+ } else {
+ /* Someone acquired it in the meantime or put a hash */
+ mono_monitor_inflate (obj);
+ return mono_monitor_try_enter_inflated (obj, ms, allow_interruption, id);
+ }
+ } else if (lock_word_is_inflated (lw)) {
+ return mono_monitor_try_enter_inflated (obj, ms, allow_interruption, id);
+ } else if (lock_word_is_flat (lw)) {
+ if (lock_word_get_owner (lw) == id) {
+ if (lock_word_is_max_nest (lw)) {
+ mono_monitor_inflate_owned (obj, id);
+ return mono_monitor_try_enter_inflated (obj, ms, allow_interruption, id);
+ } else {
+ LockWord nlw, old_lw;
+ nlw = lock_word_increment_nest (lw);
+ old_lw.sync = InterlockedCompareExchangePointer ((gpointer*)&obj->synchronisation, nlw.sync, lw.sync);
+ if (old_lw.sync != lw.sync) {
+ /* Someone else inflated it in the meantime */
+ g_assert (lock_word_is_inflated (old_lw));
+ return mono_monitor_try_enter_inflated (obj, ms, allow_interruption, id);
+ }
+ return 1;
+ }
+ } else {
+ mono_monitor_inflate (obj);
+ return mono_monitor_try_enter_inflated (obj, ms, allow_interruption, id);
+ }
+ } else if (lock_word_has_hash (lw)) {
+ mono_monitor_inflate (obj);
+ return mono_monitor_try_enter_inflated (obj, ms, allow_interruption, id);
}
- mono_mb_emit_ldloc (mb, syncp_loc);
- *syncp_true_false_branch = mono_mb_emit_short_branch (mb, branch_on_true ? CEE_BRTRUE_S : CEE_BRFALSE_S);
+ g_assert_not_reached ();
+ return -1;
}
-#endif
-
-static MonoMethod* monitor_il_fastpaths[3];
-
-gboolean
-mono_monitor_is_il_fastpath_wrapper (MonoMethod *method)
+gboolean
+mono_monitor_enter (MonoObject *obj)
{
- int i;
- for (i = 0; i < 3; ++i) {
- if (monitor_il_fastpaths [i] == method)
- return TRUE;
- }
- return FALSE;
+ return mono_monitor_try_enter_internal (obj, INFINITE, FALSE) == 1;
}
-enum {
- FASTPATH_ENTER,
- FASTPATH_ENTERV4,
- FASTPATH_EXIT
-};
-
-
-static MonoMethod*
-register_fastpath (MonoMethod *method, int idx)
+gboolean
+mono_monitor_try_enter (MonoObject *obj, guint32 ms)
{
- mono_memory_barrier ();
- monitor_il_fastpaths [idx] = method;
- return method;
+ return mono_monitor_try_enter_internal (obj, ms, FALSE) == 1;
}
-static MonoMethod*
-mono_monitor_get_fast_enter_method (MonoMethod *monitor_enter_method)
+void
+mono_monitor_exit (MonoObject *obj)
{
- MonoMethodBuilder *mb;
- MonoMethod *res;
- static MonoMethod *compare_exchange_method;
- int obj_null_branch, true_locktaken_branch = 0, syncp_null_branch, has_owner_branch, other_owner_branch, tid_branch, thin_hash_branch;
- int tid_loc, syncp_loc, owner_loc;
- gboolean is_v4 = mono_method_signature (monitor_enter_method)->param_count == 2;
- int fast_path_idx = is_v4 ? FASTPATH_ENTERV4 : FASTPATH_ENTER;
- WrapperInfo *info;
-
- /* The !is_v4 version is not used/tested */
- g_assert (is_v4);
-
- if (monitor_il_fastpaths [fast_path_idx])
- return monitor_il_fastpaths [fast_path_idx];
-
- if (!mono_get_runtime_callbacks ()->tls_key_supported (TLS_KEY_THREAD))
- return NULL;
-
- if (!compare_exchange_method) {
- MonoMethodDesc *desc;
- MonoClass *class;
-
- desc = mono_method_desc_new ("Interlocked:CompareExchange(intptr&,intptr,intptr)", FALSE);
- class = mono_class_from_name (mono_defaults.corlib, "System.Threading", "Interlocked");
- compare_exchange_method = mono_method_desc_search_in_class (desc, class);
- mono_method_desc_free (desc);
-
- if (!compare_exchange_method)
- return NULL;
- }
-
- mb = mono_mb_new (mono_defaults.monitor_class, is_v4 ? "FastMonitorEnterV4" : "FastMonitorEnter", MONO_WRAPPER_UNKNOWN);
-
- mb->method->slot = -1;
- mb->method->flags = METHOD_ATTRIBUTE_PUBLIC | METHOD_ATTRIBUTE_STATIC |
- METHOD_ATTRIBUTE_HIDE_BY_SIG | METHOD_ATTRIBUTE_FINAL;
-
-#ifndef DISABLE_JIT
- tid_loc = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
- syncp_loc = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
- owner_loc = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
-
- emit_obj_syncp_check (mb, syncp_loc, &obj_null_branch, is_v4 ? &true_locktaken_branch : NULL, &syncp_null_branch, &thin_hash_branch, FALSE);
-
- /*
- mono. tls thread_tls_offset threadp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThread, tid) threadp off
- add &tid
- ldind.i tid
- stloc tid
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, owner) syncp off
- add &owner
- ldind.i owner
- stloc owner
- ldloc owner owner
- brtrue.s tid
- */
-
- mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
- mono_mb_emit_byte (mb, CEE_MONO_TLS);
- mono_mb_emit_i4 (mb, TLS_KEY_THREAD);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoInternalThread, tid));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDIND_I);
- mono_mb_emit_stloc (mb, tid_loc);
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, owner));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDIND_I);
- mono_mb_emit_stloc (mb, owner_loc);
- mono_mb_emit_ldloc (mb, owner_loc);
- tid_branch = mono_mb_emit_short_branch (mb, CEE_BRTRUE_S);
-
- /*
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, owner) syncp off
- add &owner
- ldloc tid &owner tid
- ldc.i4 0 &owner tid 0
- call System.Threading.Interlocked.CompareExchange oldowner
- brtrue.s has_owner
- ret
- */
-
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, owner));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_ldloc (mb, tid_loc);
- mono_mb_emit_byte (mb, CEE_LDC_I4_0);
- mono_mb_emit_managed_call (mb, compare_exchange_method, NULL);
- has_owner_branch = mono_mb_emit_short_branch (mb, CEE_BRTRUE_S);
-
- if (is_v4) {
- mono_mb_emit_byte (mb, CEE_LDARG_1);
- mono_mb_emit_byte (mb, CEE_LDC_I4_1);
- mono_mb_emit_byte (mb, CEE_STIND_I1);
- }
- mono_mb_emit_byte (mb, CEE_RET);
-
- /*
- tid:
- ldloc owner owner
- ldloc tid owner tid
- brne.s other_owner
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, nest) syncp off
- add &nest
- dup &nest &nest
- ldind.i4 &nest nest
- ldc.i4 1 &nest nest 1
- add &nest nest+
- stind.i4
- ret
- */
+ LockWord lw;
+
+ LOCK_DEBUG (g_message ("%s: (%d) Unlocking %p", __func__, mono_thread_info_get_small_id (), obj));
- mono_mb_patch_short_branch (mb, tid_branch);
- mono_mb_emit_ldloc (mb, owner_loc);
- mono_mb_emit_ldloc (mb, tid_loc);
- other_owner_branch = mono_mb_emit_short_branch (mb, CEE_BNE_UN_S);
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, nest));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_DUP);
- mono_mb_emit_byte (mb, CEE_LDIND_I4);
- mono_mb_emit_byte (mb, CEE_LDC_I4_1);
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_STIND_I4);
-
- if (is_v4) {
- mono_mb_emit_byte (mb, CEE_LDARG_1);
- mono_mb_emit_byte (mb, CEE_LDC_I4_1);
- mono_mb_emit_byte (mb, CEE_STIND_I1);
+ if (G_UNLIKELY (!obj)) {
+ mono_set_pending_exception (mono_get_exception_argument_null ("obj"));
+ return;
}
- mono_mb_emit_byte (mb, CEE_RET);
-
- /*
- obj_null, syncp_null, has_owner, other_owner:
- ldarg 0 obj
- call System.Threading.Monitor.Enter
- ret
- */
-
- if (thin_hash_branch)
- mono_mb_patch_short_branch (mb, thin_hash_branch);
- mono_mb_patch_short_branch (mb, obj_null_branch);
- mono_mb_patch_short_branch (mb, syncp_null_branch);
- mono_mb_patch_short_branch (mb, has_owner_branch);
- mono_mb_patch_short_branch (mb, other_owner_branch);
- if (true_locktaken_branch)
- mono_mb_patch_short_branch (mb, true_locktaken_branch);
- mono_mb_emit_byte (mb, CEE_LDARG_0);
- if (is_v4)
- mono_mb_emit_byte (mb, CEE_LDARG_1);
- mono_mb_emit_managed_call (mb, monitor_enter_method, NULL);
- mono_mb_emit_byte (mb, CEE_RET);
-#endif
-
- res = register_fastpath (mono_mb_create_method (mb, mono_signature_no_pinvoke (monitor_enter_method), 5), fast_path_idx);
+ lw.sync = obj->synchronisation;
- info = mono_image_alloc0 (mono_defaults.corlib, sizeof (WrapperInfo));
- info->subtype = is_v4 ? WRAPPER_SUBTYPE_FAST_MONITOR_ENTER_V4 : WRAPPER_SUBTYPE_FAST_MONITOR_ENTER;
- mono_marshal_set_wrapper_info (res, info);
+ mono_monitor_ensure_owned (lw, mono_thread_info_get_small_id ());
- mono_mb_free (mb);
- return res;
+ if (G_UNLIKELY (lock_word_is_inflated (lw)))
+ mono_monitor_exit_inflated (obj);
+ else
+ mono_monitor_exit_flat (obj, lw);
}
-static MonoMethod*
-mono_monitor_get_fast_exit_method (MonoMethod *monitor_exit_method)
+guint32
+mono_monitor_get_object_monitor_gchandle (MonoObject *object)
{
- MonoMethodBuilder *mb;
- MonoMethod *res;
- int obj_null_branch, has_waiting_branch, has_syncp_branch, owned_branch, nested_branch, thin_hash_branch;
- int syncp_loc;
- WrapperInfo *info;
-
- if (monitor_il_fastpaths [FASTPATH_EXIT])
- return monitor_il_fastpaths [FASTPATH_EXIT];
-
- if (!mono_get_runtime_callbacks ()->tls_key_supported (TLS_KEY_THREAD))
- return NULL;
-
- mb = mono_mb_new (mono_defaults.monitor_class, "FastMonitorExit", MONO_WRAPPER_UNKNOWN);
-
- mb->method->slot = -1;
- mb->method->flags = METHOD_ATTRIBUTE_PUBLIC | METHOD_ATTRIBUTE_STATIC |
- METHOD_ATTRIBUTE_HIDE_BY_SIG | METHOD_ATTRIBUTE_FINAL;
-
-#ifndef DISABLE_JIT
- syncp_loc = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
-
- emit_obj_syncp_check (mb, syncp_loc, &obj_null_branch, NULL, &has_syncp_branch, &thin_hash_branch, TRUE);
-
- /*
- ret
- */
-
- mono_mb_emit_byte (mb, CEE_RET);
-
- /*
- has_syncp:
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, owner) syncp off
- add &owner
- ldind.i owner
- mono. tls thread_tls_offset owner threadp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThread, tid) owner threadp off
- add owner &tid
- ldind.i owner tid
- beq.s owned
- */
-
- mono_mb_patch_short_branch (mb, has_syncp_branch);
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, owner));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDIND_I);
- mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
- mono_mb_emit_byte (mb, CEE_MONO_TLS);
- mono_mb_emit_i4 (mb, TLS_KEY_THREAD);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoInternalThread, tid));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDIND_I);
- owned_branch = mono_mb_emit_short_branch (mb, CEE_BEQ_S);
-
- /*
- ret
- */
-
- mono_mb_emit_byte (mb, CEE_RET);
-
- /*
- owned:
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, nest) syncp off
- add &nest
- dup &nest &nest
- ldind.i4 &nest nest
- dup &nest nest nest
- ldc.i4 1 &nest nest nest 1
- bgt.un.s nested &nest nest
- */
-
- mono_mb_patch_short_branch (mb, owned_branch);
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, nest));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_DUP);
- mono_mb_emit_byte (mb, CEE_LDIND_I4);
- mono_mb_emit_byte (mb, CEE_DUP);
- mono_mb_emit_byte (mb, CEE_LDC_I4_1);
- nested_branch = mono_mb_emit_short_branch (mb, CEE_BGT_UN_S);
-
- /*
- pop &nest
- pop
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, entry_count) syncp off
- add &count
- ldind.i4 count
- brtrue.s has_waiting
- */
-
- mono_mb_emit_byte (mb, CEE_POP);
- mono_mb_emit_byte (mb, CEE_POP);
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, entry_count));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDIND_I4);
- has_waiting_branch = mono_mb_emit_short_branch (mb, CEE_BRTRUE_S);
-
- /*
- ldloc syncp syncp
- ldc.i4 MONO_STRUCT_OFFSET(MonoThreadsSync, owner) syncp off
- add &owner
- ldnull &owner 0
- stind.i
- ret
- */
-
- mono_mb_emit_ldloc (mb, syncp_loc);
- mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoThreadsSync, owner));
- mono_mb_emit_byte (mb, CEE_ADD);
- mono_mb_emit_byte (mb, CEE_LDNULL);
- mono_mb_emit_byte (mb, CEE_STIND_I);
- mono_mb_emit_byte (mb, CEE_RET);
-
- /*
- nested:
- ldc.i4 1 &nest nest 1
- sub &nest nest-
- stind.i4
- ret
- */
-
- mono_mb_patch_short_branch (mb, nested_branch);
- mono_mb_emit_byte (mb, CEE_LDC_I4_1);
- mono_mb_emit_byte (mb, CEE_SUB);
- mono_mb_emit_byte (mb, CEE_STIND_I4);
- mono_mb_emit_byte (mb, CEE_RET);
-
- /*
- obj_null, has_waiting:
- ldarg 0 obj
- call System.Threading.Monitor.Exit
- ret
- */
-
- if (thin_hash_branch)
- mono_mb_patch_short_branch (mb, thin_hash_branch);
- mono_mb_patch_short_branch (mb, obj_null_branch);
- mono_mb_patch_short_branch (mb, has_waiting_branch);
- mono_mb_emit_byte (mb, CEE_LDARG_0);
- mono_mb_emit_managed_call (mb, monitor_exit_method, NULL);
- mono_mb_emit_byte (mb, CEE_RET);
-#endif
-
- res = register_fastpath (mono_mb_create_method (mb, mono_signature_no_pinvoke (monitor_exit_method), 5), FASTPATH_EXIT);
- mono_mb_free (mb);
-
- info = mono_image_alloc0 (mono_defaults.corlib, sizeof (WrapperInfo));
- info->subtype = WRAPPER_SUBTYPE_FAST_MONITOR_EXIT;
- mono_marshal_set_wrapper_info (res, info);
+ LockWord lw;
- return res;
-}
+ lw.sync = object->synchronisation;
-MonoMethod*
-mono_monitor_get_fast_path (MonoMethod *enter_or_exit)
-{
- if (strcmp (enter_or_exit->name, "Enter") == 0)
- return mono_monitor_get_fast_enter_method (enter_or_exit);
- if (strcmp (enter_or_exit->name, "Exit") == 0)
- return mono_monitor_get_fast_exit_method (enter_or_exit);
- g_assert_not_reached ();
- return NULL;
+ if (lock_word_is_inflated (lw)) {
+ MonoThreadsSync *mon = lock_word_get_inflated_lock (lw);
+ return (guint32)mon->data;
+ }
+ return 0;
}
/*
* mono_monitor_threads_sync_member_offset:
- * @owner_offset: returns size and offset of the "owner" member
+ * @status_offset: returns size and offset of the "status" member
* @nest_offset: returns size and offset of the "nest" member
- * @entry_count_offset: returns size and offset of the "entry_count" member
*
- * Returns the offsets and sizes of three members of the
+ * Returns the offsets and sizes of two members of the
* MonoThreadsSync struct. The Monitor ASM fastpaths need this.
*/
void
-mono_monitor_threads_sync_members_offset (int *owner_offset, int *nest_offset, int *entry_count_offset)
+mono_monitor_threads_sync_members_offset (int *status_offset, int *nest_offset)
{
MonoThreadsSync ts;
#define ENCODE_OFF_SIZE(o,s) (((o) << 8) | ((s) & 0xff))
- *owner_offset = ENCODE_OFF_SIZE (MONO_STRUCT_OFFSET (MonoThreadsSync, owner), sizeof (ts.owner));
+ *status_offset = ENCODE_OFF_SIZE (MONO_STRUCT_OFFSET (MonoThreadsSync, status), sizeof (ts.status));
*nest_offset = ENCODE_OFF_SIZE (MONO_STRUCT_OFFSET (MonoThreadsSync, nest), sizeof (ts.nest));
- *entry_count_offset = ENCODE_OFF_SIZE (MONO_STRUCT_OFFSET (MonoThreadsSync, entry_count), sizeof (ts.entry_count));
}
gboolean
*lockTaken = res == 1;
}
+void
+mono_monitor_enter_v4 (MonoObject *obj, char *lock_taken)
+{
+
+ if (*lock_taken == 1) {
+ mono_set_pending_exception (mono_get_exception_argument ("lockTaken", "lockTaken is already true"));
+ return;
+ }
+
+ ves_icall_System_Threading_Monitor_Monitor_try_enter_with_atomic_var (obj, INFINITE, lock_taken);
+}
+
gboolean
ves_icall_System_Threading_Monitor_Monitor_test_owner (MonoObject *obj)
{
- MonoThreadsSync *mon;
-
- LOCK_DEBUG (g_message ("%s: Testing if %p is owned by thread %d", __func__, obj, GetCurrentThreadId()));
+ LockWord lw;
- mon = obj->synchronisation;
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH)
- return FALSE;
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
- if (mon == NULL) {
- return FALSE;
- }
-
- if(mon->owner==GetCurrentThreadId ()) {
- return(TRUE);
+ LOCK_DEBUG (g_message ("%s: Testing if %p is owned by thread %d", __func__, obj, mono_thread_info_get_small_id()));
+
+ lw.sync = obj->synchronisation;
+
+ if (lock_word_is_flat (lw)) {
+ return lock_word_get_owner (lw) == mono_thread_info_get_small_id ();
+ } else if (lock_word_is_inflated (lw)) {
+ return mon_status_get_owner (lock_word_get_inflated_lock (lw)->status) == mono_thread_info_get_small_id ();
}
return(FALSE);
gboolean
ves_icall_System_Threading_Monitor_Monitor_test_synchronised (MonoObject *obj)
{
- MonoThreadsSync *mon;
+ LockWord lw;
- LOCK_DEBUG (g_message("%s: (%d) Testing if %p is owned by any thread", __func__, GetCurrentThreadId (), obj));
-
- mon = obj->synchronisation;
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH)
- return FALSE;
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
- if (mon == NULL) {
- return FALSE;
- }
-
- if (mon->owner != 0) {
- return TRUE;
+ LOCK_DEBUG (g_message("%s: (%d) Testing if %p is owned by any thread", __func__, mono_thread_info_get_small_id (), obj));
+
+ lw.sync = obj->synchronisation;
+
+ if (lock_word_is_flat (lw)) {
+ return !lock_word_is_free (lw);
+ } else if (lock_word_is_inflated (lw)) {
+ return mon_status_get_owner (lock_word_get_inflated_lock (lw)->status) != 0;
}
-
+
return FALSE;
}
void
ves_icall_System_Threading_Monitor_Monitor_pulse (MonoObject *obj)
{
+ int id;
+ LockWord lw;
MonoThreadsSync *mon;
+
+ LOCK_DEBUG (g_message ("%s: (%d) Pulsing %p", __func__, mono_thread_info_get_small_id (), obj));
- LOCK_DEBUG (g_message ("%s: (%d) Pulsing %p", __func__, GetCurrentThreadId (), obj));
-
- mon = obj->synchronisation;
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked"));
- return;
- }
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
- if (mon == NULL) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked"));
- return;
- }
- if (mon->owner != GetCurrentThreadId ()) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked by this thread"));
+ id = mono_thread_info_get_small_id ();
+ lw.sync = obj->synchronisation;
+
+ mono_monitor_ensure_owned (lw, id);
+
+ if (!lock_word_is_inflated (lw)) {
+ /* No threads waiting. A wait would have inflated the lock */
return;
}
- LOCK_DEBUG (g_message ("%s: (%d) %d threads waiting", __func__, GetCurrentThreadId (), g_slist_length (mon->wait_list)));
-
+ mon = lock_word_get_inflated_lock (lw);
+
+ LOCK_DEBUG (g_message ("%s: (%d) %d threads waiting", __func__, mono_thread_info_get_small_id (), g_slist_length (mon->wait_list)));
+
if (mon->wait_list != NULL) {
- LOCK_DEBUG (g_message ("%s: (%d) signalling and dequeuing handle %p", __func__, GetCurrentThreadId (), mon->wait_list->data));
+ LOCK_DEBUG (g_message ("%s: (%d) signalling and dequeuing handle %p", __func__, mono_thread_info_get_small_id (), mon->wait_list->data));
SetEvent (mon->wait_list->data);
mon->wait_list = g_slist_remove (mon->wait_list, mon->wait_list->data);
void
ves_icall_System_Threading_Monitor_Monitor_pulse_all (MonoObject *obj)
{
+ int id;
+ LockWord lw;
MonoThreadsSync *mon;
- LOCK_DEBUG (g_message("%s: (%d) Pulsing all %p", __func__, GetCurrentThreadId (), obj));
+ LOCK_DEBUG (g_message("%s: (%d) Pulsing all %p", __func__, mono_thread_info_get_small_id (), obj));
- mon = obj->synchronisation;
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked"));
- return;
- }
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
- if (mon == NULL) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked"));
- return;
- }
- if (mon->owner != GetCurrentThreadId ()) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked by this thread"));
+ id = mono_thread_info_get_small_id ();
+ lw.sync = obj->synchronisation;
+
+ mono_monitor_ensure_owned (lw, id);
+
+ if (!lock_word_is_inflated (lw)) {
+ /* No threads waiting. A wait would have inflated the lock */
return;
}
- LOCK_DEBUG (g_message ("%s: (%d) %d threads waiting", __func__, GetCurrentThreadId (), g_slist_length (mon->wait_list)));
+ mon = lock_word_get_inflated_lock (lw);
+
+ LOCK_DEBUG (g_message ("%s: (%d) %d threads waiting", __func__, mono_thread_info_get_small_id (), g_slist_length (mon->wait_list)));
while (mon->wait_list != NULL) {
- LOCK_DEBUG (g_message ("%s: (%d) signalling and dequeuing handle %p", __func__, GetCurrentThreadId (), mon->wait_list->data));
+ LOCK_DEBUG (g_message ("%s: (%d) signalling and dequeuing handle %p", __func__, mono_thread_info_get_small_id (), mon->wait_list->data));
SetEvent (mon->wait_list->data);
mon->wait_list = g_slist_remove (mon->wait_list, mon->wait_list->data);
gboolean
ves_icall_System_Threading_Monitor_Monitor_wait (MonoObject *obj, guint32 ms)
{
+ LockWord lw;
MonoThreadsSync *mon;
HANDLE event;
guint32 nest;
gboolean success = FALSE;
gint32 regain;
MonoInternalThread *thread = mono_thread_internal_current ();
+ int id = mono_thread_info_get_small_id ();
- LOCK_DEBUG (g_message ("%s: (%d) Trying to wait for %p with timeout %dms", __func__, GetCurrentThreadId (), obj, ms));
-
- mon = obj->synchronisation;
-#ifdef HAVE_MOVING_COLLECTOR
- {
- LockWord lw;
- lw.sync = mon;
- if (lw.lock_word & LOCK_WORD_THIN_HASH) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked"));
- return FALSE;
- }
- lw.lock_word &= ~LOCK_WORD_BITS_MASK;
- mon = lw.sync;
- }
-#endif
- if (mon == NULL) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked"));
- return FALSE;
- }
- if (mon->owner != GetCurrentThreadId ()) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Not locked by this thread"));
- return FALSE;
+ LOCK_DEBUG (g_message ("%s: (%d) Trying to wait for %p with timeout %dms", __func__, mono_thread_info_get_small_id (), obj, ms));
+
+ lw.sync = obj->synchronisation;
+
+ mono_monitor_ensure_owned (lw, id);
+
+ if (!lock_word_is_inflated (lw)) {
+ mono_monitor_inflate_owned (obj, id);
+ lw.sync = obj->synchronisation;
}
+ mon = lock_word_get_inflated_lock (lw);
+
/* Do this WaitSleepJoin check before creating the event handle */
mono_thread_current_check_pending_interrupt ();
event = CreateEvent (NULL, FALSE, FALSE, NULL);
if (event == NULL) {
- mono_raise_exception (mono_get_exception_synchronization_lock ("Failed to set up wait event"));
+ mono_set_pending_exception (mono_get_exception_synchronization_lock ("Failed to set up wait event"));
return FALSE;
}
- LOCK_DEBUG (g_message ("%s: (%d) queuing handle %p", __func__, GetCurrentThreadId (), event));
+ LOCK_DEBUG (g_message ("%s: (%d) queuing handle %p", __func__, mono_thread_info_get_small_id (), event));
mono_thread_current_check_pending_interrupt ();
/* Save the nest count, and release the lock */
nest = mon->nest;
mon->nest = 1;
- mono_monitor_exit (obj);
+ mono_memory_write_barrier ();
+ mono_monitor_exit_inflated (obj);
- LOCK_DEBUG (g_message ("%s: (%d) Unlocked %p lock %p", __func__, GetCurrentThreadId (), obj, mon));
+ LOCK_DEBUG (g_message ("%s: (%d) Unlocked %p lock %p", __func__, mono_thread_info_get_small_id (), obj, mon));
/* There's no race between unlocking mon and waiting for the
* event, because auto reset events are sticky, and this event
* is private to this thread. Therefore even if the event was
* signalled before we wait, we still succeed.
*/
+ MONO_PREPARE_BLOCKING;
ret = WaitForSingleObjectEx (event, ms, TRUE);
+ MONO_FINISH_BLOCKING;
/* Reset the thread state fairly early, so we don't have to worry
* about the monitor error checking
/* Regain the lock with the previous nest count */
do {
- regain = mono_monitor_try_enter_internal (obj, INFINITE, TRUE);
+ regain = mono_monitor_try_enter_inflated (obj, INFINITE, TRUE, id);
if (regain == -1)
mono_thread_interruption_checkpoint ();
} while (regain == -1);
* SynchronizationLockException
*/
CloseHandle (event);
- mono_raise_exception (mono_get_exception_synchronization_lock ("Failed to regain lock"));
+ mono_set_pending_exception (mono_get_exception_synchronization_lock ("Failed to regain lock"));
return FALSE;
}
mon->nest = nest;
- LOCK_DEBUG (g_message ("%s: (%d) Regained %p lock %p", __func__, GetCurrentThreadId (), obj, mon));
+ LOCK_DEBUG (g_message ("%s: (%d) Regained %p lock %p", __func__, mono_thread_info_get_small_id (), obj, mon));
if (ret == WAIT_TIMEOUT) {
/* Poll the event again, just in case it was signalled
* while we were trying to regain the monitor lock
*/
+ MONO_PREPARE_BLOCKING;
ret = WaitForSingleObjectEx (event, 0, FALSE);
+ MONO_FINISH_BLOCKING;
}
/* Pulse will have popped our event from the queue if it signalled
*/
if (ret == WAIT_OBJECT_0) {
- LOCK_DEBUG (g_message ("%s: (%d) Success", __func__, GetCurrentThreadId ()));
+ LOCK_DEBUG (g_message ("%s: (%d) Success", __func__, mono_thread_info_get_small_id ()));
success = TRUE;
} else {
- LOCK_DEBUG (g_message ("%s: (%d) Wait failed, dequeuing handle %p", __func__, GetCurrentThreadId (), event));
+ LOCK_DEBUG (g_message ("%s: (%d) Wait failed, dequeuing handle %p", __func__, mono_thread_info_get_small_id (), event));
/* No pulse, so we have to remove ourself from the
* wait queue
*/
projects / mono.git / blobdiff