[runtime] Introduce the icall lock to be used when looking up icall related information.

4 files changed, 54 insertions, 26 deletions

diff --git a/data/lock-decoder/LockTracerDecoder.cs b/data/lock-decoder/LockTracerDecoder.cs
index b5a3f755ea5..f786e6b81dc 100644
--- a/data/lock-decoder/LockTracerDecoder.cs
+++ b/data/lock-decoder/LockTracerDecoder.cs
@@ -102,14 +102,15 @@ Global locks:
 	Adding global locks is not to be taken lightly.
 
 The current lock hierarchy:
-loader lock
-	domain lock
-		domain jit lock
+loader lock (global)
+	domain lock (complex)
+		domain jit lock (complex)
 			simple locks
 
 Examples:
 	You can take the loader lock without holding a domain lock.
-	You cannot take a domain lock if the loader lock is held.
+	You can take the domain load while holding the loader lock
+	You cannot take the loader lock if only the domain lock is held.
 	You cannot take a domain lock while holding the lock to another domain.
 */
 
@@ -120,6 +121,7 @@ public enum Lock {
 	DomainLock,
 	DomainAssembliesLock,
 	DomainJitCodeHashLock,
+	IcallLock,
 }
 
 public class SimLock
diff --git a/mono/metadata/icall.c b/mono/metadata/icall.c
index 26871d5311a..450d7cd21e6 100644
--- a/mono/metadata/icall.c
+++ b/mono/metadata/icall.c
@@ -85,6 +85,7 @@
 #include <mono/utils/mono-io-portability.h>
 #include <mono/utils/mono-digest.h>
 #include <mono/utils/bsearch.h>
+#include <mono/utils/mono-mutex.h>
 
 #if defined (HOST_WIN32)
 #include <windows.h>
@@ -7857,6 +7858,7 @@ icall_symbols [] = {
 
 #endif /* DISABLE_ICALL_TABLES */
 
+static mono_mutex_t icall_mutex;
 static GHashTable *icall_hash = NULL;
 static GHashTable *jit_icall_hash_name = NULL;
 static GHashTable *jit_icall_hash_addr = NULL;
@@ -7894,6 +7896,19 @@ mono_icall_init (void)
 #endif
 
 	icall_hash = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+	mono_mutex_init (&icall_mutex);
+}
+
+static void
+mono_icall_lock (void)
+{
+	mono_locks_mutex_acquire (&icall_mutex, IcallLock);
+}
+
+static void
+mono_icall_unlock (void)
+{
+	mono_locks_mutex_release (&icall_mutex, IcallLock);
 }
 
 void
@@ -7902,16 +7917,17 @@ mono_icall_cleanup (void)
 	g_hash_table_destroy (icall_hash);
 	g_hash_table_destroy (jit_icall_hash_name);
 	g_hash_table_destroy (jit_icall_hash_addr);
+	mono_mutex_destroy (&icall_mutex);
 }
 
 void
 mono_add_internal_call (const char *name, gconstpointer method)
 {
-	mono_loader_lock ();
+	mono_icall_lock ();
 
 	g_hash_table_insert (icall_hash, g_strdup (name), (gpointer) method);
 
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 }
 
 #ifndef DISABLE_ICALL_TABLES
@@ -8074,23 +8090,23 @@ mono_lookup_internal_call (MonoMethod *method)
 	sigstart [siglen + 2] = 0;
 	g_free (tmpsig);
 	
-	mono_loader_lock ();
+	mono_icall_lock ();
 
 	res = g_hash_table_lookup (icall_hash, mname);
 	if (res) {
-		mono_loader_unlock ();
+		mono_icall_unlock ();;
 		return res;
 	}
 	/* try without signature */
 	*sigstart = 0;
 	res = g_hash_table_lookup (icall_hash, mname);
 	if (res) {
-		mono_loader_unlock ();
+		mono_icall_unlock ();
 		return res;
 	}
 
 #ifdef DISABLE_ICALL_TABLES
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 	/* Fail only when the result is actually used */
 	/* mono_marshal_get_native_wrapper () depends on this */
 	if (method->klass == mono_defaults.string_class && !strcmp (method->name, ".ctor"))
@@ -8100,19 +8116,19 @@ mono_lookup_internal_call (MonoMethod *method)
 #else
 	/* it wasn't found in the static call tables */
 	if (!imap) {
-		mono_loader_unlock ();
+		mono_icall_unlock ();
 		return NULL;
 	}
 	res = find_method_icall (imap, sigstart - mlen);
 	if (res) {
-		mono_loader_unlock ();
+		mono_icall_unlock ();
 		return res;
 	}
 	/* try _with_ signature */
 	*sigstart = '(';
 	res = find_method_icall (imap, sigstart - mlen);
 	if (res) {
-		mono_loader_unlock ();
+		mono_icall_unlock ();
 		return res;
 	}
 
@@ -8124,7 +8140,7 @@ mono_lookup_internal_call (MonoMethod *method)
 	g_print ("If you see other errors or faults after this message they are probably related\n");
 	g_print ("and you need to fix your mono install first.\n");
 
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 
 	return NULL;
 #endif
@@ -8304,9 +8320,9 @@ mono_find_jit_icall_by_name (const char *name)
 	MonoJitICallInfo *info;
 	g_assert (jit_icall_hash_name);
 
-	mono_loader_lock ();
+	mono_icall_lock ();
 	info = g_hash_table_lookup (jit_icall_hash_name, name);
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 	return info;
 }
 
@@ -8316,9 +8332,9 @@ mono_find_jit_icall_by_addr (gconstpointer addr)
 	MonoJitICallInfo *info;
 	g_assert (jit_icall_hash_addr);
 
-	mono_loader_lock ();
+	mono_icall_lock ();
 	info = g_hash_table_lookup (jit_icall_hash_addr, (gpointer)addr);
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 
 	return info;
 }
@@ -8327,7 +8343,7 @@ mono_find_jit_icall_by_addr (gconstpointer addr)
  * mono_get_jit_icall_info:
  *
  *   Return the hashtable mapping JIT icall names to MonoJitICallInfo structures. The
- * caller should access it while holding the loader lock.
+ * caller should access it while holding the icall lock.
  */
 GHashTable*
 mono_get_jit_icall_info (void)
@@ -8346,20 +8362,20 @@ mono_lookup_jit_icall_symbol (const char *name)
 	MonoJitICallInfo *info;
 	const char *res = NULL;
 
-	mono_loader_lock ();
+	mono_icall_lock ();
 	info = g_hash_table_lookup (jit_icall_hash_name, name);
 	if (info)
 		res = info->c_symbol;
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 	return res;
 }
 
 void
 mono_register_jit_icall_wrapper (MonoJitICallInfo *info, gconstpointer wrapper)
 {
-	mono_loader_lock ();
+	mono_icall_lock ();
 	g_hash_table_insert (jit_icall_hash_addr, (gpointer)wrapper, info);
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 }
 
 MonoJitICallInfo *
@@ -8370,7 +8386,7 @@ mono_register_jit_icall_full (gconstpointer func, const char *name, MonoMethodSi
 	g_assert (func);
 	g_assert (name);
 
-	mono_loader_lock ();
+	mono_icall_lock ();
 
 	if (!jit_icall_hash_name) {
 		jit_icall_hash_name = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, g_free);
@@ -8398,7 +8414,7 @@ mono_register_jit_icall_full (gconstpointer func, const char *name, MonoMethodSi
 	g_hash_table_insert (jit_icall_hash_name, (gpointer)info->name, info);
 	g_hash_table_insert (jit_icall_hash_addr, (gpointer)func, info);
 
-	mono_loader_unlock ();
+	mono_icall_unlock ();
 	return info;
 }
 
diff --git a/mono/metadata/lock-tracer.h b/mono/metadata/lock-tracer.h
index 40beac748e8..ac9599ecbab 100644
--- a/mono/metadata/lock-tracer.h
+++ b/mono/metadata/lock-tracer.h
@@ -15,6 +15,7 @@ typedef enum {
 	DomainLock,
 	DomainAssembliesLock,
 	DomainJitCodeHashLock,
+	IcallLock
 } RuntimeLocks;
 
 #ifdef LOCK_TRACER
@@ -43,6 +44,15 @@ void mono_locks_lock_released (RuntimeLocks kind, gpointer lock) MONO_INTERNAL;
 	LeaveCriticalSection (LOCK); \
 } while (0)
 
+#define mono_locks_mutex_acquire(LOCK, NAME) do { \
+	mono_mutex_lock (LOCK); \
+	mono_locks_lock_acquired (NAME, LOCK); \
+} while (0)
+
+#define mono_locks_mutex_release(LOCK, NAME) do { \
+	mono_locks_lock_released (NAME, LOCK); \
+	mono_mutex_unlock (LOCK); \
+} while (0)
 G_END_DECLS
 
 #endif /* __MONO_METADATA_LOCK_TRACER_H__ */
diff --git a/mono/mini/aot-compiler.c b/mono/mini/aot-compiler.c
index 9723c34b4cd..f8de62212bc 100755
--- a/mono/mini/aot-compiler.c
+++ b/mono/mini/aot-compiler.c
@@ -3408,7 +3408,7 @@ add_wrappers (MonoAotCompile *acfg)
 #endif
 
 		/* JIT icall wrappers */
-		/* FIXME: locking */
+		/* FIXME: locking - this is "safe" as full-AOT threads don't mutate the icall hash*/
 		g_hash_table_foreach (mono_get_jit_icall_info (), add_jit_icall_wrapper, acfg);
 	}