[for-next][PATCH 16/33] ftrace: Convert the rest of the function trigger over to the mapping functions

[Steven Rostedt]

From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

As the data pointer for individual ips will soon be removed and no longer
passed to the callback function probe handlers, convert the rest of the function
trigger counters over to the new ftrace_func_mapper helper functions.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
 kernel/trace/trace_functions.c | 123 ++++++++++++++++++++++++++++-------------
 1 file changed, 85 insertions(+), 38 deletions(-)

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index b99f6231281e..d9cbde8575a8 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -267,10 +267,12 @@ static struct tracer function_trace __tracer_data =
 };
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-static void update_traceon_count(void **data, bool on)
+static void update_traceon_count(struct ftrace_probe_ops *ops,
+				 unsigned long ip, bool on)
 {
-	long *count = (long *)data;
-	long old_count = *count;
+	struct ftrace_func_mapper *mapper = ops->private_data;
+	long *count;
+	long old_count;
 
 	/*
 	 * Tracing gets disabled (or enabled) once per count.
@@ -301,7 +303,10 @@ static void update_traceon_count(void **data, bool on)
 	 * setting the tracing_on file. But we currently don't care
 	 * about that.
 	 */
-	if (!old_count)
+	count = (long *)ftrace_func_mapper_find_ip(mapper, ip);
+	old_count = *count;
+
+	if (old_count <= 0)
 		return;
 
 	/* Make sure we see count before checking tracing state */
@@ -315,10 +320,6 @@ static void update_traceon_count(void **data, bool on)
 	else
 		tracing_off();
 
-	/* unlimited? */
-	if (old_count == -1)
-		return;
-
 	/* Make sure tracing state is visible before updating count */
 	smp_wmb();
 
@@ -329,14 +330,14 @@ static void
 ftrace_traceon_count(unsigned long ip, unsigned long parent_ip,
 		     struct ftrace_probe_ops *ops, void **data)
 {
-	update_traceon_count(data, 1);
+	update_traceon_count(ops, ip, 1);
 }
 
 static void
 ftrace_traceoff_count(unsigned long ip, unsigned long parent_ip,
 		      struct ftrace_probe_ops *ops, void **data)
 {
-	update_traceon_count(data, 0);
+	update_traceon_count(ops, ip, 0);
 }
 
 static void
@@ -379,47 +380,56 @@ static void
 ftrace_stacktrace_count(unsigned long ip, unsigned long parent_ip,
 			struct ftrace_probe_ops *ops, void **data)
 {
-	long *count = (long *)data;
+	struct ftrace_func_mapper *mapper = ops->private_data;
+	long *count;
 	long old_count;
 	long new_count;
 
+	if (!tracing_is_on())
+		return;
+
+	/* unlimited? */
+	if (!mapper) {
+		trace_dump_stack(STACK_SKIP);
+		return;
+	}
+
+	count = (long *)ftrace_func_mapper_find_ip(mapper, ip);
+
 	/*
 	 * Stack traces should only execute the number of times the
 	 * user specified in the counter.
 	 */
 	do {
-
-		if (!tracing_is_on())
-			return;
-
 		old_count = *count;
 
 		if (!old_count)
 			return;
 
-		/* unlimited? */
-		if (old_count == -1) {
-			trace_dump_stack(STACK_SKIP);
-			return;
-		}
-
 		new_count = old_count - 1;
 		new_count = cmpxchg(count, old_count, new_count);
 		if (new_count == old_count)
 			trace_dump_stack(STACK_SKIP);
 
+		if (!tracing_is_on())
+			return;
+
 	} while (new_count != old_count);
 }
 
-static int update_count(void **data)
+static int update_count(struct ftrace_probe_ops *ops, unsigned long ip)
 {
-	unsigned long *count = (long *)data;
+	struct ftrace_func_mapper *mapper = ops->private_data;
+	long *count = NULL;
 
-	if (!*count)
-		return 0;
+	if (mapper)
+		count = (long *)ftrace_func_mapper_find_ip(mapper, ip);
 
-	if (*count != -1)
+	if (count) {
+		if (*count <= 0)
+			return 0;
 		(*count)--;
+	}
 
 	return 1;
 }
@@ -428,7 +438,7 @@ static void
 ftrace_dump_probe(unsigned long ip, unsigned long parent_ip,
 	struct ftrace_probe_ops *ops, void **data)
 {
-	if (update_count(data))
+	if (update_count(ops, ip))
 		ftrace_dump(DUMP_ALL);
 }
 
@@ -437,22 +447,26 @@ static void
 ftrace_cpudump_probe(unsigned long ip, unsigned long parent_ip,
 	struct ftrace_probe_ops *ops, void **data)
 {
-	if (update_count(data))
+	if (update_count(ops, ip))
 		ftrace_dump(DUMP_ORIG);
 }
 
 static int
 ftrace_probe_print(const char *name, struct seq_file *m,
-		   unsigned long ip, void *data)
+		   unsigned long ip, struct ftrace_probe_ops *ops)
 {
-	long count = (long)data;
+	struct ftrace_func_mapper *mapper = ops->private_data;
+	long *count = NULL;
 
 	seq_printf(m, "%ps:%s", (void *)ip, name);
 
-	if (count == -1)
-		seq_puts(m, ":unlimited\n");
+	if (mapper)
+		count = (long *)ftrace_func_mapper_find_ip(mapper, ip);
+
+	if (count)
+		seq_printf(m, ":count=%ld\n", *count);
 	else
-		seq_printf(m, ":count=%ld\n", count);
+		seq_puts(m, ":unlimited\n");
 
 	return 0;
 }
@@ -461,55 +475,82 @@ static int
 ftrace_traceon_print(struct seq_file *m, unsigned long ip,
 			 struct ftrace_probe_ops *ops, void *data)
 {
-	return ftrace_probe_print("traceon", m, ip, data);
+	return ftrace_probe_print("traceon", m, ip, ops);
 }
 
 static int
 ftrace_traceoff_print(struct seq_file *m, unsigned long ip,
 			 struct ftrace_probe_ops *ops, void *data)
 {
-	return ftrace_probe_print("traceoff", m, ip, data);
+	return ftrace_probe_print("traceoff", m, ip, ops);
 }
 
 static int
 ftrace_stacktrace_print(struct seq_file *m, unsigned long ip,
 			struct ftrace_probe_ops *ops, void *data)
 {
-	return ftrace_probe_print("stacktrace", m, ip, data);
+	return ftrace_probe_print("stacktrace", m, ip, ops);
 }
 
 static int
 ftrace_dump_print(struct seq_file *m, unsigned long ip,
 			struct ftrace_probe_ops *ops, void *data)
 {
-	return ftrace_probe_print("dump", m, ip, data);
+	return ftrace_probe_print("dump", m, ip, ops);
 }
 
 static int
 ftrace_cpudump_print(struct seq_file *m, unsigned long ip,
 			struct ftrace_probe_ops *ops, void *data)
 {
-	return ftrace_probe_print("cpudump", m, ip, data);
+	return ftrace_probe_print("cpudump", m, ip, ops);
+}
+
+
+static int
+ftrace_count_init(struct ftrace_probe_ops *ops, unsigned long ip,
+		     void **data)
+{
+	struct ftrace_func_mapper *mapper = ops->private_data;
+
+	return ftrace_func_mapper_add_ip(mapper, ip, *data);
+}
+
+static void
+ftrace_count_free(struct ftrace_probe_ops *ops, unsigned long ip,
+		  void **_data)
+{
+	struct ftrace_func_mapper *mapper = ops->private_data;
+
+	ftrace_func_mapper_remove_ip(mapper, ip);
 }
 
 static struct ftrace_probe_ops traceon_count_probe_ops = {
 	.func			= ftrace_traceon_count,
 	.print			= ftrace_traceon_print,
+	.init			= ftrace_count_init,
+	.free			= ftrace_count_free,
 };
 
 static struct ftrace_probe_ops traceoff_count_probe_ops = {
 	.func			= ftrace_traceoff_count,
 	.print			= ftrace_traceoff_print,
+	.init			= ftrace_count_init,
+	.free			= ftrace_count_free,
 };
 
 static struct ftrace_probe_ops stacktrace_count_probe_ops = {
 	.func			= ftrace_stacktrace_count,
 	.print			= ftrace_stacktrace_print,
+	.init			= ftrace_count_init,
+	.free			= ftrace_count_free,
 };
 
 static struct ftrace_probe_ops dump_probe_ops = {
 	.func			= ftrace_dump_probe,
 	.print			= ftrace_dump_print,
+	.init			= ftrace_count_init,
+	.free			= ftrace_count_free,
 };
 
 static struct ftrace_probe_ops cpudump_probe_ops = {
@@ -558,6 +599,12 @@ ftrace_trace_probe_callback(struct ftrace_probe_ops *ops,
 	if (!strlen(number))
 		goto out_reg;
 
+	if (!ops->private_data) {
+		ops->private_data = allocate_ftrace_func_mapper();
+		if (!ops->private_data)
+			return -ENOMEM;
+	}
+
 	/*
 	 * We use the callback data field (which is a pointer)
 	 * as our counter.
-- 
2.10.2