From: Pierre-Marc Fournier <pierre-marc.fournier@polymtl.ca>
Date: Tue, 27 Oct 2009 21:36:58 +0000 (-0400)
Subject: trace_mark: pass register values to probe
X-Git-Tag: v0.1~74
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=75667d04f4c255687def1876cf15baf3bbd1ffc5;p=ust.git

trace_mark: pass register values to probe

This should be more efficient, disableable or done inside the probe. For GDB static tracepoints.
---

diff --git a/libust/marker.c b/libust/marker.c
index 8b12019..d4514f1 100644
--- a/libust/marker.c
+++ b/libust/marker.c
@@ -89,7 +89,7 @@ struct marker_entry {
 	char *format;
 	char *name;
 			/* Probe wrapper */
-	void (*call)(const struct marker *mdata, void *call_private, ...);
+	void (*call)(const struct marker *mdata, void *call_private, struct registers *regs, ...);
 	struct marker_probe_closure single;
 	struct marker_probe_closure *multi;
 	int refcount;	/* Number of times armed. 0 if disarmed. */
@@ -125,7 +125,7 @@ static void marker_update_processes(void)
  * operations that modifies the execution flow of preemptible code.
  */
 notrace void __mark_empty_function(const struct marker *mdata,
-	void *probe_private, void *call_private, const char *fmt, va_list *args)
+	void *probe_private, struct registers *regs, void *call_private, const char *fmt, va_list *args)
 {
 }
 //ust// EXPORT_SYMBOL_GPL(__mark_empty_function);
@@ -141,7 +141,7 @@ notrace void __mark_empty_function(const struct marker *mdata,
  * rcu_dereference() for the pointer read.
  */
 notrace void marker_probe_cb(const struct marker *mdata,
-		void *call_private, ...)
+		void *call_private, struct registers *regs, ...)
 {
 	va_list args;
 	char ptype;
@@ -162,8 +162,8 @@ notrace void marker_probe_cb(const struct marker *mdata,
 		/* Must read the ptr before private data. They are not data
 		 * dependant, so we put an explicit smp_rmb() here. */
 		smp_rmb();
-		va_start(args, call_private);
-		func(mdata, mdata->single.probe_private, call_private,
+		va_start(args, regs);
+		func(mdata, mdata->single.probe_private, regs, call_private,
 			mdata->format, &args);
 		va_end(args);
 	} else {
@@ -183,9 +183,9 @@ notrace void marker_probe_cb(const struct marker *mdata,
 		 */
 		smp_read_barrier_depends();
 		for (i = 0; multi[i].func; i++) {
-			va_start(args, call_private);
+			va_start(args, regs);
 			multi[i].func(mdata, multi[i].probe_private,
-				call_private, mdata->format, &args);
+				regs, call_private, mdata->format, &args);
 			va_end(args);
 		}
 	}
@@ -202,7 +202,7 @@ notrace void marker_probe_cb(const struct marker *mdata,
  * Should be connected to markers "MARK_NOARGS".
  */
 static notrace void marker_probe_cb_noarg(const struct marker *mdata,
-		void *call_private, ...)
+		void *call_private, struct registers *regs, ...)
 {
 	va_list args;	/* not initialized */
 	char ptype;
@@ -218,7 +218,7 @@ static notrace void marker_probe_cb_noarg(const struct marker *mdata,
 		/* Must read the ptr before private data. They are not data
 		 * dependant, so we put an explicit smp_rmb() here. */
 		smp_rmb();
-		func(mdata, mdata->single.probe_private, call_private,
+		func(mdata, mdata->single.probe_private, regs, call_private,
 			mdata->format, &args);
 	} else {
 		struct marker_probe_closure *multi;
@@ -237,7 +237,7 @@ static notrace void marker_probe_cb_noarg(const struct marker *mdata,
 		 */
 		smp_read_barrier_depends();
 		for (i = 0; multi[i].func; i++)
-			multi[i].func(mdata, multi[i].probe_private,
+			multi[i].func(mdata, multi[i].probe_private, regs,
 				call_private, mdata->format, &args);
 	}
 //ust//	rcu_read_unlock_sched_notrace();
diff --git a/libust/marker.h b/libust/marker.h
index 246d174..06f2b93 100644
--- a/libust/marker.h
+++ b/libust/marker.h
@@ -51,7 +51,7 @@ struct marker;
  * format string to recover the variable argument list.
  */
 typedef void marker_probe_func(const struct marker *mdata,
-		void *probe_private, void *call_private,
+		void *probe_private, struct registers *regs, void *call_private,
 		const char *fmt, va_list *args);
 
 struct marker_probe_closure {
@@ -70,7 +70,7 @@ struct marker {
 				/* Probe wrapper */
 	u16 channel_id;		/* Numeric channel identifier, dynamic */
 	u16 event_id;		/* Numeric event identifier, dynamic */
-	void (*call)(const struct marker *mdata, void *call_private, ...);
+	void (*call)(const struct marker *mdata, void *call_private, struct registers *regs, ...);
 	struct marker_probe_closure single;
 	struct marker_probe_closure *multi;
 	const char *tp_name;	/* Optional tracepoint name */
@@ -85,6 +85,7 @@ struct marker {
 		static const char __mstrtab_##channel##_##name[]	\
 		__attribute__((section("__markers_strings")))		\
 		= #channel "\0" #name "\0" format;			\
+		struct registers regs;					\
 		static struct marker __mark_##channel##_##name		\
 		__attribute__((section("__markers"), aligned(8))) =	\
 		{ __mstrtab_##channel##_##name,				\
@@ -128,13 +129,13 @@ struct marker {
 					__mark_##channel##_##name.state))) \
 				(*__mark_##channel##_##name.call)	\
 					(&__mark_##channel##_##name,	\
-					call_private, ## args);		\
+					call_private, &regs, ## args);		\
 		} else {						\
 			if (unlikely(_imv_read(				\
 					__mark_##channel##_##name.state))) \
 				(*__mark_##channel##_##name.call)	\
 					(&__mark_##channel##_##name,	\
-					call_private, ## args);		\
+					call_private, &regs, ## args);		\
 		}							\
 	} while (0)
 
@@ -148,7 +149,7 @@ struct marker {
 		DEFINE_MARKER_TP(channel, name, tp_name, tp_cb, format);\
 		__mark_check_format(format, ## args);			\
 		(*__mark_##channel##_##name.call)(&__mark_##channel##_##name, \
-			call_private, ## args);				\
+			call_private, &regs, ## args);				\
 	} while (0)
 
 extern void marker_update_probe_range(struct marker *begin,
@@ -242,7 +243,7 @@ static inline void __printf(1, 2) ___mark_check_format(const char *fmt, ...)
 extern marker_probe_func __mark_empty_function;
 
 extern void marker_probe_cb(const struct marker *mdata,
-	void *call_private, ...);
+	void *call_private, struct registers *regs, ...);
 
 /*
  * Connect a probe to a marker.
diff --git a/libust/serialize.c b/libust/serialize.c
index 0055d99..f9e45b6 100644
--- a/libust/serialize.c
+++ b/libust/serialize.c
@@ -583,7 +583,8 @@ void ltt_write_event_data(struct rchan_buf *buf, size_t buf_offset,
 
 
 notrace void ltt_vtrace(const struct marker *mdata, void *probe_data,
-			void *call_data, const char *fmt, va_list *args)
+			struct registers *regs, void *call_data,
+			const char *fmt, va_list *args)
 {
 	int largest_align, ret;
 	struct ltt_active_marker *pdata;
@@ -697,12 +698,13 @@ notrace void ltt_vtrace(const struct marker *mdata, void *probe_data,
 }
 
 notrace void ltt_trace(const struct marker *mdata, void *probe_data,
-		       void *call_data, const char *fmt, ...)
+		       struct registers *regs, void *call_data,
+		       const char *fmt, ...)
 {
 	va_list args;
 
 	va_start(args, fmt);
-	ltt_vtrace(mdata, probe_data, call_data, fmt, &args);
+	ltt_vtrace(mdata, probe_data, regs, call_data, fmt, &args);
 	va_end(args);
 }
 
diff --git a/libust/tracer.h b/libust/tracer.h
index 601d19a..b2ac930 100644
--- a/libust/tracer.h
+++ b/libust/tracer.h
@@ -110,9 +110,9 @@ struct ltt_active_marker {
 
 struct marker; //ust//
 extern void ltt_vtrace(const struct marker *mdata, void *probe_data,
-	void *call_data, const char *fmt, va_list *args);
+	struct registers *regs, void *call_data, const char *fmt, va_list *args);
 extern void ltt_trace(const struct marker *mdata, void *probe_data,
-	void *call_data, const char *fmt, ...);
+	struct registers *regs, void *call_data, const char *fmt, ...);
 
 /*
  * Unique ID assigned to each registered probe.