Merge tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "No new features this release. Mostly clean ups, restructuring and
  documentation.

   - Have ftrace_bug() show ftrace errors before the WARN, as the WARN
     will reboot the box before the error messages are printed if
     panic_on_warn is set.

   - Have traceoff_on_warn disable tracing sooner (before prints)

   - Write a message to the trace buffer that its being disabled when
     disable_trace_on_warning() is set.

   - Separate out synthetic events from histogram code to let it be used
     by other parts of the kernel.

   - More documentation on histogram design.

   - Other small fixes and clean ups"

* tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove obsolete PREEMPTIRQ_EVENTS kconfig option
  tracing/doc: Fix ascii-art in histogram-design.rst
  tracing: Add a trace print when traceoff_on_warning is triggered
  ftrace,bug: Improve traceoff_on_warn
  selftests/ftrace: Distinguish between hist and synthetic event checks
  tracing: Move synthetic events to a separate file
  tracing: Fix events.rst section numbering
  tracing/doc: Fix typos in histogram-design.rst
  tracing: Add hist_debug trace event files for histogram debugging
  tracing: Add histogram-design document
  tracing: Check state.disabled in synth event trace functions
  tracing/probe: reverse arguments to list_add
  tools/bootconfig: Add a summary of test cases and return error
  ftrace: show debugging information when panic_on_warn set

10 files changed, 2157 insertions, 1814 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 24876faac753..a4020c0b4508 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -249,15 +249,6 @@ config TRACE_PREEMPT_TOGGLE
 	  Enables hooks which will be called when preemption is first disabled,
 	  and last enabled.
 
-config PREEMPTIRQ_EVENTS
-	bool "Enable trace events for preempt and irq disable/enable"
-	select TRACE_IRQFLAGS
-	select TRACE_PREEMPT_TOGGLE if PREEMPTION
-	select GENERIC_TRACER
-	default n
-	help
-	  Enable tracing of disable and enable events for preemption and irqs.
-
 config IRQSOFF_TRACER
 	bool "Interrupts-off Latency Tracer"
 	default n
@@ -614,12 +605,30 @@ config TRACING_MAP
 	  generally used outside of that context, and is normally
 	  selected by tracers that use it.
 
+config SYNTH_EVENTS
+	bool "Synthetic trace events"
+	select TRACING
+	select DYNAMIC_EVENTS
+	default n
+	help
+	  Synthetic events are user-defined trace events that can be
+	  used to combine data from other trace events or in fact any
+	  data source.  Synthetic events can be generated indirectly
+	  via the trace() action of histogram triggers or directly
+	  by way of an in-kernel API.
+
+	  See Documentation/trace/events.rst or
+	  Documentation/trace/histogram.rst for details and examples.
+
+	  If in doubt, say N.
+
 config HIST_TRIGGERS
 	bool "Histogram triggers"
 	depends on ARCH_HAVE_NMI_SAFE_CMPXCHG
 	select TRACING_MAP
 	select TRACING
 	select DYNAMIC_EVENTS
+	select SYNTH_EVENTS
 	default n
 	help
 	  Hist triggers allow one or more arbitrary trace event fields
@@ -815,7 +824,7 @@ config PREEMPTIRQ_DELAY_TEST
 
 config SYNTH_EVENT_GEN_TEST
 	tristate "Test module for in-kernel synthetic event generation"
-	depends on HIST_TRIGGERS
+	depends on SYNTH_EVENTS
 	help
           This option creates a test module to check the base
           functionality of in-kernel synthetic event definition and
@@ -838,6 +847,29 @@ config KPROBE_EVENT_GEN_TEST
 
 	  If unsure, say N.
 
+config HIST_TRIGGERS_DEBUG
+	bool "Hist trigger debug support"
+	depends on HIST_TRIGGERS
+	help
+          Add "hist_debug" file for each event, which when read will
+          dump out a bunch of internal details about the hist triggers
+          defined on that event.
+
+          The hist_debug file serves a couple of purposes:
+
+            - Helps developers verify that nothing is broken.
+
+            - Provides educational information to support the details
+              of the hist trigger internals as described by
+              Documentation/trace/histogram-design.rst.
+
+          The hist_debug output only covers the data structures
+          related to the histogram definitions themselves and doesn't
+          display the internals of map buckets or variable values of
+          running histograms.
+
+          If unsure, say N.
+
 endif # FTRACE
 
 endif # TRACING_SUPPORT
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index f9dcd19165fa..1d8aaa546412 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -72,6 +72,7 @@ endif
 obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
 obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o
 obj-$(CONFIG_TRACE_EVENT_INJECT) += trace_events_inject.o
+obj-$(CONFIG_SYNTH_EVENTS) += trace_events_synth.o
 obj-$(CONFIG_HIST_TRIGGERS) += trace_events_hist.o
 obj-$(CONFIG_BPF_EVENTS) += bpf_trace.o
 obj-$(CONFIG_KPROBE_EVENTS) += trace_kprobe.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 7d0ebd104706..c163c3531faf 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2016,14 +2016,14 @@ void ftrace_bug(int failed, struct dyn_ftrace *rec)
 {
 	unsigned long ip = rec ? rec->ip : 0;
 
+	pr_info("------------[ ftrace bug ]------------\n");
+
 	switch (failed) {
 	case -EFAULT:
-		FTRACE_WARN_ON_ONCE(1);
 		pr_info("ftrace faulted on modifying ");
 		print_ip_sym(KERN_INFO, ip);
 		break;
 	case -EINVAL:
-		FTRACE_WARN_ON_ONCE(1);
 		pr_info("ftrace failed to modify ");
 		print_ip_sym(KERN_INFO, ip);
 		print_ip_ins(" actual:   ", (unsigned char *)ip);
@@ -2034,12 +2034,10 @@ void ftrace_bug(int failed, struct dyn_ftrace *rec)
 		}
 		break;
 	case -EPERM:
-		FTRACE_WARN_ON_ONCE(1);
 		pr_info("ftrace faulted on writing ");
 		print_ip_sym(KERN_INFO, ip);
 		break;
 	default:
-		FTRACE_WARN_ON_ONCE(1);
 		pr_info("ftrace faulted on unknown error ");
 		print_ip_sym(KERN_INFO, ip);
 	}
@@ -2066,6 +2064,8 @@ void ftrace_bug(int failed, struct dyn_ftrace *rec)
 		ip = ftrace_get_addr_curr(rec);
 		pr_cont("\n expected tramp: %lx\n", ip);
 	}
+
+	FTRACE_WARN_ON_ONCE(1);
 }
 
 static int ftrace_check_record(struct dyn_ftrace *rec, bool enable, bool update)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 3ab27022c20f..ec44b0e2a19c 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1299,8 +1299,11 @@ EXPORT_SYMBOL_GPL(tracing_off);
 
 void disable_trace_on_warning(void)
 {
-	if (__disable_trace_on_warning)
+	if (__disable_trace_on_warning) {
+		trace_array_printk_buf(global_trace.array_buffer.buffer, _THIS_IP_,
+			"Disabling tracing due to warning\n");
 		tracing_off();
+	}
 }
 
 /**
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 4eb1d004d5f2..def769df5bf1 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1661,6 +1661,7 @@ extern struct list_head ftrace_events;
 
 extern const struct file_operations event_trigger_fops;
 extern const struct file_operations event_hist_fops;
+extern const struct file_operations event_hist_debug_fops;
 extern const struct file_operations event_inject_fops;
 
 #ifdef CONFIG_HIST_TRIGGERS
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 242f59e7f17d..f6f55682d3e2 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2209,6 +2209,10 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file)
 	trace_create_file("hist", 0444, file->dir, file,
 			  &event_hist_fops);
 #endif
+#ifdef CONFIG_HIST_TRIGGERS_DEBUG
+	trace_create_file("hist_debug", 0444, file->dir, file,
+			  &event_hist_debug_fops);
+#endif
 	trace_create_file("format", 0444, file->dir, call,
 			  &ftrace_event_format_fops);
 
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index fcab11cc6833..0b933546142e 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -19,13 +19,7 @@
 #include <trace/events/mmflags.h>
 
 #include "tracing_map.h"
-#include "trace.h"
-#include "trace_dynevent.h"
-
-#define SYNTH_SYSTEM		"synthetic"
-#define SYNTH_FIELDS_MAX	32
-
-#define STR_VAR_LEN_MAX		32 /* must be multiple of sizeof(u64) */
+#include "trace_synth.h"
 
 #define ERRORS								\
 	C(NONE,			"No error"),				\
@@ -380,69 +374,6 @@ struct hist_trigger_data {
 	unsigned int			n_save_var_str;
 };
 
-static int create_synth_event(int argc, const char **argv);
-static int synth_event_show(struct seq_file *m, struct dyn_event *ev);
-static int synth_event_release(struct dyn_event *ev);
-static bool synth_event_is_busy(struct dyn_event *ev);
-static bool synth_event_match(const char *system, const char *event,
-			int argc, const char **argv, struct dyn_event *ev);
-
-static struct dyn_event_operations synth_event_ops = {
-	.create = create_synth_event,
-	.show = synth_event_show,
-	.is_busy = synth_event_is_busy,
-	.free = synth_event_release,
-	.match = synth_event_match,
-};
-
-struct synth_field {
-	char *type;
-	char *name;
-	size_t size;
-	unsigned int offset;
-	bool is_signed;
-	bool is_string;
-};
-
-struct synth_event {
-	struct dyn_event			devent;
-	int					ref;
-	char					*name;
-	struct synth_field			**fields;
-	unsigned int				n_fields;
-	unsigned int				n_u64;
-	struct trace_event_class		class;
-	struct trace_event_call			call;
-	struct tracepoint			*tp;
-	struct module				*mod;
-};
-
-static bool is_synth_event(struct dyn_event *ev)
-{
-	return ev->ops == &synth_event_ops;
-}
-
-static struct synth_event *to_synth_event(struct dyn_event *ev)
-{
-	return container_of(ev, struct synth_event, devent);
-}
-
-static bool synth_event_is_busy(struct dyn_event *ev)
-{
-	struct synth_event *event = to_synth_event(ev);
-
-	return event->ref != 0;
-}
-
-static bool synth_event_match(const char *system, const char *event,
-			int argc, const char **argv, struct dyn_event *ev)
-{
-	struct synth_event *sev = to_synth_event(ev);
-
-	return strcmp(sev->name, event) == 0 &&
-		(!system || strcmp(system, SYNTH_SYSTEM) == 0);
-}
-
 struct action_data;
 
 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
@@ -589,6 +520,7 @@ static struct track_data *track_data_alloc(unsigned int key_len,
 		track_data_free(data);
 		return ERR_PTR(-ENOMEM);
 	}
+
 	data->elt.private_data = elt_data;
 
 	elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL);
@@ -621,7 +553,6 @@ static void last_cmd_set(struct trace_event_file *file, char *str)
 
 	if (file) {
 		call = file->event_call;
-
 		system = call->class->system;
 		if (system) {
 			name = trace_event_name(call);
@@ -646,510 +577,6 @@ static void hist_err_clear(void)
 	last_cmd_loc[0] = '\0';
 }
 
-struct synth_trace_event {
-	struct trace_entry	ent;
-	u64			fields[];
-};
-
-static int synth_event_define_fields(struct trace_event_call *call)
-{
-	struct synth_trace_event trace;
-	int offset = offsetof(typeof(trace), fields);
-	struct synth_event *event = call->data;
-	unsigned int i, size, n_u64;
-	char *name, *type;
-	bool is_signed;
-	int ret = 0;
-
-	for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
-		size = event->fields[i]->size;
-		is_signed = event->fields[i]->is_signed;
-		type = event->fields[i]->type;
-		name = event->fields[i]->name;
-		ret = trace_define_field(call, type, name, offset, size,
-					 is_signed, FILTER_OTHER);
-		if (ret)
-			break;
-
-		event->fields[i]->offset = n_u64;
-
-		if (event->fields[i]->is_string) {
-			offset += STR_VAR_LEN_MAX;
-			n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
-		} else {
-			offset += sizeof(u64);
-			n_u64++;
-		}
-	}
-
-	event->n_u64 = n_u64;
-
-	return ret;
-}
-
-static bool synth_field_signed(char *type)
-{
-	if (str_has_prefix(type, "u"))
-		return false;
-	if (strcmp(type, "gfp_t") == 0)
-		return false;
-
-	return true;
-}
-
-static int synth_field_is_string(char *type)
-{
-	if (strstr(type, "char[") != NULL)
-		return true;
-
-	return false;
-}
-
-static int synth_field_string_size(char *type)
-{
-	char buf[4], *end, *start;
-	unsigned int len;
-	int size, err;
-
-	start = strstr(type, "char[");
-	if (start == NULL)
-		return -EINVAL;
-	start += sizeof("char[") - 1;
-
-	end = strchr(type, ']');
-	if (!end || end < start)
-		return -EINVAL;
-
-	len = end - start;
-	if (len > 3)
-		return -EINVAL;
-
-	strncpy(buf, start, len);
-	buf[len] = '\0';
-
-	err = kstrtouint(buf, 0, &size);
-	if (err)
-		return err;
-
-	if (size > STR_VAR_LEN_MAX)
-		return -EINVAL;
-
-	return size;
-}
-
-static int synth_field_size(char *type)
-{
-	int size = 0;
-
-	if (strcmp(type, "s64") == 0)
-		size = sizeof(s64);
-	else if (strcmp(type, "u64") == 0)
-		size = sizeof(u64);
-	else if (strcmp(type, "s32") == 0)
-		size = sizeof(s32);
-	else if (strcmp(type, "u32") == 0)
-		size = sizeof(u32);
-	else if (strcmp(type, "s16") == 0)
-		size = sizeof(s16);
-	else if (strcmp(type, "u16") == 0)
-		size = sizeof(u16);
-	else if (strcmp(type, "s8") == 0)
-		size = sizeof(s8);
-	else if (strcmp(type, "u8") == 0)
-		size = sizeof(u8);
-	else if (strcmp(type, "char") == 0)
-		size = sizeof(char);
-	else if (strcmp(type, "unsigned char") == 0)
-		size = sizeof(unsigned char);
-	else if (strcmp(type, "int") == 0)
-		size = sizeof(int);
-	else if (strcmp(type, "unsigned int") == 0)
-		size = sizeof(unsigned int);
-	else if (strcmp(type, "long") == 0)
-		size = sizeof(long);
-	else if (strcmp(type, "unsigned long") == 0)
-		size = sizeof(unsigned long);
-	else if (strcmp(type, "pid_t") == 0)
-		size = sizeof(pid_t);
-	else if (strcmp(type, "gfp_t") == 0)
-		size = sizeof(gfp_t);
-	else if (synth_field_is_string(type))
-		size = synth_field_string_size(type);
-
-	return size;
-}
-
-static const char *synth_field_fmt(char *type)
-{
-	const char *fmt = "%llu";
-
-	if (strcmp(type, "s64") == 0)
-		fmt = "%lld";
-	else if (strcmp(type, "u64") == 0)
-		fmt = "%llu";
-	else if (strcmp(type, "s32") == 0)
-		fmt = "%d";
-	else if (strcmp(type, "u32") == 0)
-		fmt = "%u";
-	else if (strcmp(type, "s16") == 0)
-		fmt = "%d";
-	else if (strcmp(type, "u16") == 0)
-		fmt = "%u";
-	else if (strcmp(type, "s8") == 0)
-		fmt = "%d";
-	else if (strcmp(type, "u8") == 0)
-		fmt = "%u";
-	else if (strcmp(type, "char") == 0)
-		fmt = "%d";
-	else if (strcmp(type, "unsigned char") == 0)
-		fmt = "%u";
-	else if (strcmp(type, "int") == 0)
-		fmt = "%d";
-	else if (strcmp(type, "unsigned int") == 0)
-		fmt = "%u";
-	else if (strcmp(type, "long") == 0)
-		fmt = "%ld";
-	else if (strcmp(type, "unsigned long") == 0)
-		fmt = "%lu";
-	else if (strcmp(type, "pid_t") == 0)
-		fmt = "%d";
-	else if (strcmp(type, "gfp_t") == 0)
-		fmt = "%x";
-	else if (synth_field_is_string(type))
-		fmt = "%s";
-
-	return fmt;
-}
-
-static void print_synth_event_num_val(struct trace_seq *s,
-				      char *print_fmt, char *name,
-				      int size, u64 val, char *space)
-{
-	switch (size) {
-	case 1:
-		trace_seq_printf(s, print_fmt, name, (u8)val, space);
-		break;
-
-	case 2:
-		trace_seq_printf(s, print_fmt, name, (u16)val, space);
-		break;
-
-	case 4:
-		trace_seq_printf(s, print_fmt, name, (u32)val, space);
-		break;
-
-	default:
-		trace_seq_printf(s, print_fmt, name, val, space);
-		break;
-	}
-}
-
-static enum print_line_t print_synth_event(struct trace_iterator *iter,
-					   int flags,
-					   struct trace_event *event)
-{
-	struct trace_array *tr = iter->tr;
-	struct trace_seq *s = &iter->seq;
-	struct synth_trace_event *entry;
-	struct synth_event *se;
-	unsigned int i, n_u64;
-	char print_fmt[32];
-	const char *fmt;
-
-	entry = (struct synth_trace_event *)iter->ent;
-	se = container_of(event, struct synth_event, call.event);
-
-	trace_seq_printf(s, "%s: ", se->name);
-
-	for (i = 0, n_u64 = 0; i < se->n_fields; i++) {
-		if (trace_seq_has_overflowed(s))
-			goto end;
-
-		fmt = synth_field_fmt(se->fields[i]->type);
-
-		/* parameter types */
-		if (tr && tr->trace_flags & TRACE_ITER_VERBOSE)
-			trace_seq_printf(s, "%s ", fmt);
-
-		snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt);
-
-		/* parameter values */
-		if (se->fields[i]->is_string) {
-			trace_seq_printf(s, print_fmt, se->fields[i]->name,
-					 (char *)&entry->fields[n_u64],
-					 i == se->n_fields - 1 ? "" : " ");
-			n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
-		} else {
-			struct trace_print_flags __flags[] = {
-			    __def_gfpflag_names, {-1, NULL} };
-			char *space = (i == se->n_fields - 1 ? "" : " ");
-
-			print_synth_event_num_val(s, print_fmt,
-						  se->fields[i]->name,
-						  se->fields[i]->size,
-						  entry->fields[n_u64],
-						  space);
-
-			if (strcmp(se->fields[i]->type, "gfp_t") == 0) {
-				trace_seq_puts(s, " (");
-				trace_print_flags_seq(s, "|",
-						      entry->fields[n_u64],
-						      __flags);
-				trace_seq_putc(s, ')');
-			}
-			n_u64++;
-		}
-	}
-end:
-	trace_seq_putc(s, '\n');
-
-	return trace_handle_return(s);
-}
-
-static struct trace_event_functions synth_event_funcs = {
-	.trace		= print_synth_event
-};
-
-static notrace void trace_event_raw_event_synth(void *__data,
-						u64 *var_ref_vals,
-						unsigned int *var_ref_idx)
-{
-	struct trace_event_file *trace_file = __data;
-	struct synth_trace_event *entry;
-	struct trace_event_buffer fbuffer;
-	struct trace_buffer *buffer;
-	struct synth_event *event;
-	unsigned int i, n_u64, val_idx;
-	int fields_size = 0;
-
-	event = trace_file->event_call->data;
-
-	if (trace_trigger_soft_disabled(trace_file))
-		return;
-
-	fields_size = event->n_u64 * sizeof(u64);
-
-	/*
-	 * Avoid ring buffer recursion detection, as this event
-	 * is being performed within another event.
-	 */
-	buffer = trace_file->tr->array_buffer.buffer;
-	ring_buffer_nest_start(buffer);
-
-	entry = trace_event_buffer_reserve(&fbuffer, trace_file,
-					   sizeof(*entry) + fields_size);
-	if (!entry)
-		goto out;
-
-	for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
-		val_idx = var_ref_idx[i];
-		if (event->fields[i]->is_string) {
-			char *str_val = (char *)(long)var_ref_vals[val_idx];
-			char *str_field = (char *)&entry->fields[n_u64];
-
-			strscpy(str_field, str_val, STR_VAR_LEN_MAX);
-			n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
-		} else {
-			struct synth_field *field = event->fields[i];
-			u64 val = var_ref_vals[val_idx];
-
-			switch (field->size) {
-			case 1:
-				*(u8 *)&entry->fields[n_u64] = (u8)val;
-				break;
-
-			case 2:
-				*(u16 *)&entry->fields[n_u64] = (u16)val;
-				break;
-
-			case 4:
-				*(u32 *)&entry->fields[n_u64] = (u32)val;
-				break;
-
-			default:
-				entry->fields[n_u64] = val;
-				break;
-			}
-			n_u64++;
-		}
-	}
-
-	trace_event_buffer_commit(&fbuffer);
-out:
-	ring_buffer_nest_end(buffer);
-}
-
-static void free_synth_event_print_fmt(struct trace_event_call *call)
-{
-	if (call) {
-		kfree(call->print_fmt);
-		call->print_fmt = NULL;
-	}
-}
-
-static int __set_synth_event_print_fmt(struct synth_event *event,
-				       char *buf, int len)
-{
-	const char *fmt;
-	int pos = 0;
-	int i;
-
-	/* When len=0, we just calculate the needed length */
-#define LEN_OR_ZERO (len ? len - pos : 0)
-
-	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
-	for (i = 0; i < event->n_fields; i++) {
-		fmt = synth_field_fmt(event->fields[i]->type);
-		pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s",
-				event->fields[i]->name, fmt,
-				i == event->n_fields - 1 ? "" : ", ");
-	}
-	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
-
-	for (i = 0; i < event->n_fields; i++) {
-		pos += snprintf(buf + pos, LEN_OR_ZERO,
-				", REC->%s", event->fields[i]->name);
-	}
-
-#undef LEN_OR_ZERO
-
-	/* return the length of print_fmt */
-	return pos;
-}
-
-static int set_synth_event_print_fmt(struct trace_event_call *call)
-{
-	struct synth_event *event = call->data;
-	char *print_fmt;
-	int len;
-
-	/* First: called with 0 length to calculate the needed length */
-	len = __set_synth_event_print_fmt(event, NULL, 0);
-
-	print_fmt = kmalloc(len + 1, GFP_KERNEL);
-	if (!print_fmt)
-		return -ENOMEM;
-
-	/* Second: actually write the @print_fmt */
-	__set_synth_event_print_fmt(event, print_fmt, len + 1);
-	call->print_fmt = print_fmt;
-
-	return 0;
-}
-
-static void free_synth_field(struct synth_field *field)
-{
-	kfree(field->type);
-	kfree(field->name);
-	kfree(field);
-}
-
-static struct synth_field *parse_synth_field(int argc, const char **argv,
-					     int *consumed)
-{
-	struct synth_field *field;
-	const char *prefix = NULL, *field_type = argv[0], *field_name, *array;
-	int len, ret = 0;
-
-	if (field_type[0] == ';')
-		field_type++;
-
-	if (!strcmp(field_type, "unsigned")) {
-		if (argc < 3)
-			return ERR_PTR(-EINVAL);
-		prefix = "unsigned ";
-		field_type = argv[1];
-		field_name = argv[2];
-		*consumed = 3;
-	} else {
-		field_name = argv[1];
-		*consumed = 2;
-	}
-
-	field = kzalloc(sizeof(*field), GFP_KERNEL);
-	if (!field)
-		return ERR_PTR(-ENOMEM);
-
-	len = strlen(field_name);
-	array = strchr(field_name, '[');
-	if (array)
-		len -= strlen(array);
-	else if (field_name[len - 1] == ';')
-		len--;
-
-	field->name = kmemdup_nul(field_name, len, GFP_KERNEL);
-	if (!field->name) {
-		ret = -ENOMEM;
-		goto free;
-	}
-
-	if (field_type[0] == ';')
-		field_type++;
-	len = strlen(field_type) + 1;
-	if (array)
-		len += strlen(array);
-	if (prefix)
-		len += strlen(prefix);
-
-	field->type = kzalloc(len, GFP_KERNEL);
-	if (!field->type) {
-		ret = -ENOMEM;
-		goto free;
-	}
-	if (prefix)
-		strcat(field->type, prefix);
-	strcat(field->type, field_type);
-	if (array) {
-		strcat(field->type, array);
-		if (field->type[len - 1] == ';')
-			field->type[len - 1] = '\0';
-	}
-
-	field->size = synth_field_size(field->type);
-	if (!field->size) {
-		ret = -EINVAL;
-		goto free;
-	}
-
-	if (synth_field_is_string(field->type))
-		field->is_string = true;
-
-	field->is_signed = synth_field_signed(field->type);
-
- out:
-	return field;
- free:
-	free_synth_field(field);
-	field = ERR_PTR(ret);
-	goto out;
-}
-
-static void free_synth_tracepoint(struct tracepoint *tp)
-{
-	if (!tp)
-		return;
-
-	kfree(tp->name);
-	kfree(tp);
-}
-
-static struct tracepoint *alloc_synth_tracepoint(char *name)
-{
-	struct tracepoint *tp;
-
-	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
-	if (!tp)
-		return ERR_PTR(-ENOMEM);
-
-	tp->name = kstrdup(name, GFP_KERNEL);
-	if (!tp->name) {
-		kfree(tp);
-		return ERR_PTR(-ENOMEM);
-	}
-
-	return tp;
-}
-
 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
 				    unsigned int *var_ref_idx);
 
@@ -1177,145 +604,6 @@ static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
 	}
 }
 
-static struct synth_event *find_synth_event(const char *name)
-{
-	struct dyn_event *pos;
-	struct synth_event *event;
-
-	for_each_dyn_event(pos) {
-		if (!is_synth_event(pos))
-			continue;
-		event = to_synth_event(pos);
-		if (strcmp(event->name, name) == 0)
-			return event;
-	}
-
-	return NULL;
-}
-
-static struct trace_event_fields synth_event_fields_array[] = {
-	{ .type = TRACE_FUNCTION_TYPE,
-	  .define_fields = synth_event_define_fields },
-	{}
-};
-
-static int register_synth_event(struct synth_event *event)
-{
-	struct trace_event_call *call = &event->call;
-	int ret = 0;
-
-	event->call.class = &event->class;
-	event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL);
-	if (!event->class.system) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	event->tp = alloc_synth_tracepoint(event->name);
-	if (IS_ERR(event->tp)) {
-		ret = PTR_ERR(event->tp);
-		event->tp = NULL;
-		goto out;
-	}
-
-	INIT_LIST_HEAD(&call->class->fields);
-	call->event.funcs = &synth_event_funcs;
-	call->class->fields_array = synth_event_fields_array;
-
-	ret = register_trace_event(&call->event);
-	if (!ret) {
-		ret = -ENODEV;
-		goto out;
-	}
-	call->flags = TRACE_EVENT_FL_TRACEPOINT;
-	call->class->reg = trace_event_reg;
-	call->class->probe = trace_event_raw_event_synth;
-	call->data = event;
-	call->tp = event->tp;
-
-	ret = trace_add_event_call(call);
-	if (ret) {
-		pr_warn("Failed to register synthetic event: %s\n",
-			trace_event_name(call));
-		goto err;
-	}
-
-	ret = set_synth_event_print_fmt(call);
-	if (ret < 0) {
-		trace_remove_event_call(call);
-		goto err;
-	}
- out:
-	return ret;
- err:
-	unregister_trace_event(&call->event);
-	goto out;
-}
-
-static int unregister_synth_event(struct synth_event *event)
-{
-	struct trace_event_call *call = &event->call;
-	int ret;
-
-	ret = trace_remove_event_call(call);
-
-	return ret;
-}
-
-static void free_synth_event(struct synth_event *event)
-{
-	unsigned int i;
-
-	if (!event)
-		return;
-
-	for (i = 0; i < event->n_fields; i++)
-		free_synth_field(event->fields[i]);
-
-	kfree(event->fields);
-	kfree(event->name);
-	kfree(event->class.system);
-	free_synth_tracepoint(event->tp);
-	free_synth_event_print_fmt(&event->call);
-	kfree(event);
-}
-
-static struct synth_event *alloc_synth_event(const char *name, int n_fields,
-					     struct synth_field **fields)
-{
-	struct synth_event *event;
-	unsigned int i;
-
-	event = kzalloc(sizeof(*event), GFP_KERNEL);
-	if (!event) {
-		event = ERR_PTR(-ENOMEM);
-		goto out;
-	}
-
-	event->name = kstrdup(name, GFP_KERNEL);
-	if (!event->name) {
-		kfree(event);
-		event = ERR_PTR(-ENOMEM);
-		goto out;
-	}
-
-	event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL);
-	if (!event->fields) {
-		free_synth_event(event);
-		event = ERR_PTR(-ENOMEM);
-		goto out;
-	}
-
-	dyn_event_init(&event->devent, &synth_event_ops);
-
-	for (i = 0; i < n_fields; i++)
-		event->fields[i] = fields[i];
-
-	event->n_fields = n_fields;
- out:
-	return event;
-}
-
 static void action_trace(struct hist_trigger_data *hist_data,
 			 struct tracing_map_elt *elt, void *rec,
 			 struct ring_buffer_event *rbe, void *key,
@@ -1331,1056 +619,6 @@ struct hist_var_data {
 	struct hist_trigger_data *hist_data;
 };
 
-static int synth_event_check_arg_fn(void *data)
-{
-	struct dynevent_arg_pair *arg_pair = data;
-	int size;
-
-	size = synth_field_size((char *)arg_pair->lhs);
-
-	return size ? 0 : -EINVAL;
-}
-
-/**
- * synth_event_add_field - Add a new field to a synthetic event cmd
- * @cmd: A pointer to the dynevent_cmd struct representing the new event
- * @type: The type of the new field to add
- * @name: The name of the new field to add
- *
- * Add a new field to a synthetic event cmd object.  Field ordering is in
- * the same order the fields are added.
- *
- * See synth_field_size() for available types. If field_name contains
- * [n] the field is considered to be an array.
- *
- * Return: 0 if successful, error otherwise.
- */
-int synth_event_add_field(struct dynevent_cmd *cmd, const char *type,
-			  const char *name)
-{
-	struct dynevent_arg_pair arg_pair;
-	int ret;
-
-	if (cmd->type != DYNEVENT_TYPE_SYNTH)
-		return -EINVAL;
-
-	if (!type || !name)
-		return -EINVAL;
-
-	dynevent_arg_pair_init(&arg_pair, 0, ';');
-
-	arg_pair.lhs = type;
-	arg_pair.rhs = name;
-
-	ret = dynevent_arg_pair_add(cmd, &arg_pair, synth_event_check_arg_fn);
-	if (ret)
-		return ret;
-
-	if (++cmd->n_fields > SYNTH_FIELDS_MAX)
-		ret = -EINVAL;
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(synth_event_add_field);
-
-/**
- * synth_event_add_field_str - Add a new field to a synthetic event cmd
- * @cmd: A pointer to the dynevent_cmd struct representing the new event
- * @type_name: The type and name of the new field to add, as a single string
- *
- * Add a new field to a synthetic event cmd object, as a single
- * string.  The @type_name string is expected to be of the form 'type
- * name', which will be appended by ';'.  No sanity checking is done -
- * what's passed in is assumed to already be well-formed.  Field
- * ordering is in the same order the fields are added.
- *
- * See synth_field_size() for available types. If field_name contains
- * [n] the field is considered to be an array.
- *
- * Return: 0 if successful, error otherwise.
- */
-int synth_event_add_field_str(struct dynevent_cmd *cmd, const char *type_name)
-{
-	struct dynevent_arg arg;
-	int ret;
-
-	if (cmd->type != DYNEVENT_TYPE_SYNTH)
-		return -EINVAL;
-
-	if (!type_name)
-		return -EINVAL;
-
-	dynevent_arg_init(&arg, ';');
-
-	arg.str = type_name;
-
-	ret = dynevent_arg_add(cmd, &arg, NULL);
-	if (ret)
-		return ret;
-
-	if (++cmd->n_fields > SYNTH_FIELDS_MAX)
-		ret = -EINVAL;
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(synth_event_add_field_str);
-
-/**
- * synth_event_add_fields - Add multiple fields to a synthetic event cmd
- * @cmd: A pointer to the dynevent_cmd struct representing the new event
- * @fields: An array of type/name field descriptions
- * @n_fields: The number of field descriptions contained in the fields array
- *
- * Add a new set of fields to a synthetic event cmd object.  The event
- * fields that will be defined for the event should be passed in as an
- * array of struct synth_field_desc, and the number of elements in the
- * array passed in as n_fields.  Field ordering will retain the
- * ordering given in the fields array.
- *
- * See synth_field_size() for available types. If field_name contains
- * [n] the field is considered to be an array.
- *
- * Return: 0 if successful, error otherwise.
- */
-int synth_event_add_fields(struct dynevent_cmd *cmd,
-			   struct synth_field_desc *fields,
-			   unsigned int n_fields)
-{
-	unsigned int i;
-	int ret = 0;
-
-	for (i = 0; i < n_fields; i++) {
-		if (fields[i].type == NULL || fields[i].name == NULL) {
-			ret = -EINVAL;
-			break;
-		}
-
-		ret = synth_event_add_field(cmd, fields[i].type, fields[i].name);
-		if (ret)
-			break;
-	}
-
-	return ret;
-}
-EXPORT_SYMBOL_GPL(synth_event_add_fields);
-
-/**
- * __synth_event_gen_cmd_start - Start a synthetic event command from arg list
- * @cmd: A pointer to the dynevent_cmd struct r