libc: remove residues of noux fork support

repos/libports/lib/symbols/libc

@@ -983,7 +983,6 @@ _ZN4Libc14pthread_createEPP7pthreadRN6Genode6ThreadE T
 #
 # Libc plugin interface
 #
-_ZN4Libc16schedule_suspendEPFvvE T
 _ZN4Libc25File_descriptor_allocator15find_by_libc_fdEi T
 _ZN4Libc25File_descriptor_allocator4freeEPNS_15File_descriptorE T
 _ZN4Libc25File_descriptor_allocator5allocEPNS_6PluginEPNS_14Plugin_contextEi T

repos/libports/src/lib/libc/internal/kernel.h

@@ -233,7 +233,6 @@ struct Libc::Kernel final : Vfs::Io_response_handler,
 		bool              _app_returned = false;
 
 		bool _resume_main_once  = false;
-		bool _suspend_scheduled = false;
 
 		Select_handler_base *_scheduled_select_handler = nullptr;
 
@@ -297,20 +296,6 @@ struct Libc::Kernel final : Vfs::Io_response_handler,
 
 		Absolute_path _cwd { "/" };
 
-		struct Resumer
-		{
-			GENODE_RPC(Rpc_resume, void, resume);
-			GENODE_RPC_INTERFACE(Rpc_resume);
-		};
-
-		struct Resumer_component : Rpc_object<Resumer, Resumer_component>
-		{
-			Kernel &_kernel;
-
-			Resumer_component(Kernel &kernel) : _kernel(kernel) { }
-
-			void resume() { _kernel.run_after_resume(); }
-		};
 
 		/**
 		 * Trampoline to application (user) code
@@ -447,7 +432,7 @@ struct Libc::Kernel final : Vfs::Io_response_handler,
 
 			/* _setjmp() returned after _longjmp() - user context suspended */
 
-			while ((!_app_returned) && (!_suspend_scheduled)) {
+			while ((!_app_returned)) {
 
 				if (_kernel_routine) {
 					Kernel_routine &routine = *_kernel_routine;
@@ -479,25 +464,6 @@ struct Libc::Kernel final : Vfs::Io_response_handler,
 				if (!_kernel_routine && _resume_main_once && !_setjmp(_kernel_context))
 					_switch_to_user();
 			}
-
-			_suspend_scheduled = false;
-		}
-
-		/*
-		 * Run libc application main context after suspend and resume
-		 */
-		void run_after_resume()
-		{
-			if (!_setjmp(_kernel_context))
-				_switch_to_user();
-
-			while ((!_app_returned) && (!_suspend_scheduled)) {
-				_env.ep().wait_and_dispatch_one_io_signal();
-				if (_resume_main_once && !_setjmp(_kernel_context))
-					_switch_to_user();
-			}
-
-			_suspend_scheduled = false;
 		}
 
 		/**
@@ -590,11 +556,6 @@ struct Libc::Kernel final : Vfs::Io_response_handler,
 			return _timer_accessor.timer().curr_time();
 		}
 
-		/**
-		 * Called from the main context (by fork)
-		 */
-		void schedule_suspend(void(*original_suspended_callback) ());
-
 		/**
 		 * Select interface
 		 */
@@ -611,33 +572,6 @@ struct Libc::Kernel final : Vfs::Io_response_handler,
 			_scheduled_select_handler = nullptr;
 		}
 
-		/**
-		 * Called from the context of the initial thread (on fork)
-		 */
-		void entrypoint_suspended()
-		{
-			_resume_main_handler.destruct();
-
-			_original_suspended_callback();
-		}
-
-		/**
-		 * Called from the context of the initial thread (after fork)
-		 */
-		void entrypoint_resumed()
-		{
-			_resume_main_handler.construct(_env.ep(), *this, &Kernel::_resume_main);
-
-			Resumer_component resumer { *this };
-
-			Capability<Resumer> resumer_cap =
-				_env.ep().rpc_ep().manage(&resumer);
-
-			resumer_cap.call<Resumer::Rpc_resume>();
-
-			_env.ep().rpc_ep().dissolve(&resumer);
-		}
-
 		/**
 		 * Return if main is currently suspended
 		 */

repos/libports/src/lib/libc/internal/legacy.h

@@ -26,11 +26,6 @@ namespace Libc {
 	 * XXX  called only by 'Libc::Vfs_plugin::read'
 	 */
 	void dispatch_pending_io_signals();
-
-	/*
-	 * XXX  this function is solely needed to support noux fork mechanism
-	 */
-	void schedule_suspend(void (*) ());
 }
 
 #endif /* _LIBC__INTERNAL__LEGACY_H_ */

repos/libports/src/lib/libc/kernel.cc

@@ -40,28 +40,6 @@ inline void Libc::Main_blockade::wakeup()
 }
 
 
-/**
- * Main context execution was suspended (on fork)
- *
- * This function is executed in the context of the initial thread.
- */
-static void suspended_callback()
-{
-	Libc::Kernel::kernel().entrypoint_suspended();
-}
-
-
-/**
- * Resume main context execution (after fork)
- *
- * This function is executed in the context of the initial thread.
- */
-static void resumed_callback()
-{
-	Libc::Kernel::kernel().entrypoint_resumed();
-}
-
-
 size_t Libc::Kernel::_user_stack_size()
 {
 	size_t size = Component::stack_size();
@@ -75,31 +53,6 @@ size_t Libc::Kernel::_user_stack_size()
 }
 
 
-void Libc::Kernel::schedule_suspend(void(*original_suspended_callback) ())
-{
-	if (_state != USER) {
-		error(__PRETTY_FUNCTION__, " called from non-user context");
-		return;
-	}
-
-	/*
-	 * We hook into suspend-resume callback chain to destruct and
-	 * reconstruct parts of the kernel from the context of the initial
-	 * thread, i.e., without holding any object locks.
-	 */
-	_original_suspended_callback = original_suspended_callback;
-	_env.ep().schedule_suspend(suspended_callback, resumed_callback);
-
-	if (!_setjmp(_user_context)) {
-		_valid_user_context = true;
-		_suspend_scheduled = true;
-		_switch_to_kernel();
-	} else {
-		_valid_user_context = false;
-	}
-}
-
-
 void Libc::Kernel::reset_malloc_heap()
 {
 	_malloc_ram.construct(_heap, _env.ram());

repos/libports/src/lib/libc/legacy.cc

@@ -24,8 +24,3 @@ void Libc::dispatch_pending_io_signals()
 	Kernel::kernel().dispatch_pending_io_signals();
 }
 
-
-void Libc::schedule_suspend(void (*suspended) ())
-{
-	Kernel::kernel().schedule_suspend(suspended);
-}