lxip: Fix timeout handling for 'schedule_timeout'

Up until now 'schedule_timeout' did only wait for the next signal to occur.
However, we might run into situations where there won't occur signals for longer
periods of time. Therefore, we took care of the respective timeout handling.

This commit also adds Genode's tracing support

Issue #1310

repos/dde_linux/src/lib/lxip/include/lx_emul.h

@@ -3324,6 +3324,9 @@ void trace_udp_fail_queue_rcv_skb(int, struct sock*);
 void set_sock_wait(struct socket *sock, unsigned long ptr);
 int socket_check_state(struct socket *sock);
 void log_sock(struct socket *sock);
+
+void lx_trace_event(char const *, ...) __attribute__((format(printf, 1, 2)));
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

repos/dde_linux/src/lib/lxip/include/packet_handler.h

@@ -28,7 +28,7 @@ namespace Net {
  */
 class Net::Packet_handler
 {
-	private:
+	protected:
 
 		/**
 		 * submit queue not empty anymore
@@ -53,8 +53,6 @@ class Net::Packet_handler
 		 */
 		void _ready_to_submit(unsigned) { }
 
-	protected:
-
 		Genode::Signal_dispatcher<Packet_handler> _sink_ack;
 		Genode::Signal_dispatcher<Packet_handler> _sink_submit;
 		Genode::Signal_dispatcher<Packet_handler> _source_ack;
@@ -66,8 +64,6 @@ class Net::Packet_handler
 
 		virtual Packet_stream_sink< ::Nic::Session::Policy>   * sink()   = 0;
 		virtual Packet_stream_source< ::Nic::Session::Policy> * source() = 0;
-
-		void packet_avail() { _packet_avail(1); }
 };
 
 #endif /* _PACKET_HANDLER_H_ */

repos/dde_linux/src/lib/lxip/lxcc_emul.cc

@@ -14,6 +14,8 @@
 #include <base/snprintf.h>
 #include <dataspace/client.h>
 #include <rm_session/connection.h>
+#include <timer_session/connection.h>
+#include <trace/timestamp.h>
 
 #include <lx_emul.h>
 #include <env.h>
@@ -502,10 +504,25 @@ unsigned long ilog2(unsigned long n) { return Genode::log2<unsigned long>(n); }
  ** linux/sched.h **
  *******************/
 
-extern "C" void __wait_event()
+
+static void __wait_event(signed long timeout)
 {
-	Genode::Signal s = Net::Env::receiver()->wait_for_signal();
+		static Timer::Connection timer;
-	static_cast<Genode::Signal_dispatcher_base *>(s.context())->dispatch(s.num());
+		/* timeout is relative in jiffies, make it absolute */
+		timeout += jiffies;
+
+		 /* wait for signal and return upon timeout */
+		while (timeout > jiffies  && !Net::Env::receiver()->pending())
+		{
+			timer.msleep(1);
+			//dde_kit_thread_msleep(1);
+			if (timeout <= jiffies)
+				return;
+		}
+
+		/* dispatch signal */
+		Genode::Signal s = Net::Env::receiver()->wait_for_signal();
+		static_cast<Genode::Signal_dispatcher_base *>(s.context())->dispatch(s.num());
 }
 
 
@@ -518,14 +535,14 @@ long schedule_timeout_uninterruptible(signed long timeout)
 signed long schedule_timeout(signed long timeout)
 {
 	long start = jiffies;
-	__wait_event();
+	__wait_event(timeout);
 	timeout -= jiffies - start;
 	return timeout < 0 ? 0 : timeout;
 }
 
 void poll_wait(struct file * filp, wait_queue_head_t * wait_address, poll_table *p)
 {
-	__wait_event();
+	__wait_event(0);
 }
 
 
@@ -634,3 +651,30 @@ void put_page(struct page *page)
 }
 
 
+static void create_event(char const *fmt, va_list list)
+{
+	enum { BUFFER_LEN = 64, EVENT_LEN = BUFFER_LEN + 32 };
+	char buf[BUFFER_LEN];
+
+	using namespace Genode;
+
+	String_console sc(buf, BUFFER_LEN);
+	sc.vprintf(fmt, list);
+
+	char event[EVENT_LEN];
+	static Trace::Timestamp last = 0;
+	       Trace::Timestamp now  = Trace::timestamp();
+	Genode::snprintf(event, sizeof(event), "delta = %llu ms %s",
+	                 (now - last) / 2260000, buf);
+	Thread_base::trace(event);
+	last = now;
+}
+
+
+extern "C" void lx_trace_event(char const *fmt, ...)
+{
+	va_list list;
+	va_start(list, fmt);
+	create_event(fmt, list);
+	va_end(list);
+}