Merge tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Restructure of lockdep and latency tracers

   This is the biggest change. Joel Fernandes restructured the hooks
   from irqs and preemption disabling and enabling. He got rid of a lot
   of the preprocessor #ifdef mess that they caused.

   He turned both lockdep and the latency tracers to use trace events
   inserted in the preempt/irqs disabling paths. But unfortunately,
   these started to cause issues in corner cases. Thus, parts of the
   code was reverted back to where lockdep and the latency tracers just
   get called directly (without using the trace events). But because the
   original change cleaned up the code very nicely we kept that, as well
   as the trace events for preempt and irqs disabling, but they are
   limited to not being called in NMIs.

 - Have trace events use SRCU for "rcu idle" calls. This was required
   for the preempt/irqs off trace events. But it also had to not allow
   them to be called in NMI context. Waiting till Paul makes an NMI safe
   SRCU API.

 - New notrace SRCU API to allow trace events to use SRCU.

 - Addition of mcount-nop option support

 - SPDX headers replacing GPL templates.

 - Various other fixes and clean ups.

 - Some fixes are marked for stable, but were not fully tested before
   the merge window opened.

* tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  tracing: Fix SPDX format headers to use C++ style comments
  tracing: Add SPDX License format tags to tracing files
  tracing: Add SPDX License format to bpf_trace.c
  blktrace: Add SPDX License format header
  s390/ftrace: Add -mfentry and -mnop-mcount support
  tracing: Add -mcount-nop option support
  tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
  tracing: Handle CC_FLAGS_FTRACE more accurately
  Uprobe: Additional argument arch_uprobe to uprobe_write_opcode()
  Uprobes: Simplify uprobe_register() body
  tracepoints: Free early tracepoints after RCU is initialized
  uprobes: Use synchronize_rcu() not synchronize_sched()
  tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
  ftrace: Remove unused pointer ftrace_swapper_pid
  tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing/irqsoff: Handle preempt_count for different configs
  tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing: irqsoff: Account for additional preempt_disable
  trace: Use rcu_dereference_raw for hooks from trace-event subsystem
  tracing/kprobes: Fix within_notrace_func() to check only notrace functions
  ...

35 files changed, 472 insertions, 423 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 9a27f146fa1c..c042a455afc6 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -47,6 +47,11 @@ config HAVE_FENTRY
 	help
 	  Arch supports the gcc options -pg with -mfentry
 
+config HAVE_NOP_MCOUNT
+	bool
+	help
+	  Arch supports the gcc options -pg with -mrecord-mcount and -nop-mcount
+
 config HAVE_C_RECORDMCOUNT
 	bool
 	help
@@ -82,6 +87,15 @@ config RING_BUFFER_ALLOW_SWAP
 	 Allow the use of ring_buffer_swap_cpu.
 	 Adds a very slight overhead to tracing when enabled.
 
+config PREEMPTIRQ_TRACEPOINTS
+	bool
+	depends on TRACE_PREEMPT_TOGGLE || TRACE_IRQFLAGS
+	select TRACING
+	default y
+	help
+	  Create preempt/irq toggle tracepoints if needed, so that other parts
+	  of the kernel can use them to generate or add hooks to them.
+
 # All tracer options should select GENERIC_TRACER. For those options that are
 # enabled by all tracers (context switch and event tracer) they select TRACING.
 # This allows those options to appear when no other tracer is selected. But the
@@ -155,18 +169,20 @@ config FUNCTION_GRAPH_TRACER
 	  the return value. This is done by setting the current return
 	  address on the current task structure into a stack of calls.
 
+config TRACE_PREEMPT_TOGGLE
+	bool
+	help
+	  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
-	depends on DEBUG_PREEMPT || !PROVE_LOCKING
-	depends on TRACING
+	select TRACE_PREEMPT_TOGGLE if PREEMPT
+	select GENERIC_TRACER
 	default n
 	help
 	  Enable tracing of disable and enable events for preemption and irqs.
-	  For tracing preempt disable/enable events, DEBUG_PREEMPT must be
-	  enabled. For tracing irq disable/enable events, PROVE_LOCKING must
-	  be disabled.
 
 config IRQSOFF_TRACER
 	bool "Interrupts-off Latency Tracer"
@@ -203,6 +219,7 @@ config PREEMPT_TRACER
 	select RING_BUFFER_ALLOW_SWAP
 	select TRACER_SNAPSHOT
 	select TRACER_SNAPSHOT_PER_CPU_SWAP
+	select TRACE_PREEMPT_TOGGLE
 	help
 	  This option measures the time spent in preemption-off critical
 	  sections, with microsecond accuracy.
@@ -456,6 +473,26 @@ config KPROBE_EVENTS
 	  This option is also required by perf-probe subcommand of perf tools.
 	  If you want to use perf tools, this option is strongly recommended.
 
+config KPROBE_EVENTS_ON_NOTRACE
+	bool "Do NOT protect notrace function from kprobe events"
+	depends on KPROBE_EVENTS
+	depends on KPROBES_ON_FTRACE
+	default n
+	help
+	  This is only for the developers who want to debug ftrace itself
+	  using kprobe events.
+
+	  If kprobes can use ftrace instead of breakpoint, ftrace related
+	  functions are protected from kprobe-events to prevent an infinit
+	  recursion or any unexpected execution path which leads to a kernel
+	  crash.
+
+	  This option disables such protection and allows you to put kprobe
+	  events on ftrace functions for debugging ftrace by itself.
+	  Note that this might let you shoot yourself in the foot.
+
+	  If unsure, say N.
+
 config UPROBE_EVENTS
 	bool "Enable uprobes-based dynamic events"
 	depends on ARCH_SUPPORTS_UPROBES
@@ -687,6 +724,21 @@ config RING_BUFFER_STARTUP_TEST
 
 	 If unsure, say N
 
+config PREEMPTIRQ_DELAY_TEST
+	tristate "Preempt / IRQ disable delay thread to test latency tracers"
+	depends on m
+	help
+	  Select this option to build a test module that can help test latency
+	  tracers by executing a preempt or irq disable section with a user
+	  configurable delay. The module busy waits for the duration of the
+	  critical section.
+
+	  For example, the following invocation forces a one-time irq-disabled
+	  critical section for 500us:
+	  modprobe preemptirq_delay_test test_mode=irq delay=500000
+
+	  If unsure, say N
+
 config TRACE_EVAL_MAP_FILE
        bool "Show eval mappings for trace events"
        depends on TRACING
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index e2538c7638d4..98d53b39a8ee 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -13,6 +13,11 @@ obj-y += trace_selftest_dynamic.o
 endif
 endif
 
+ifdef CONFIG_FTRACE_STARTUP_TEST
+CFLAGS_trace_kprobe_selftest.o = $(CC_FLAGS_FTRACE)
+obj-$(CONFIG_KPROBE_EVENTS) += trace_kprobe_selftest.o
+endif
+
 # If unlikely tracing is enabled, do not trace these files
 ifdef CONFIG_TRACING_BRANCHES
 KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
@@ -33,9 +38,10 @@ obj-$(CONFIG_TRACING) += trace_seq.o
 obj-$(CONFIG_TRACING) += trace_stat.o
 obj-$(CONFIG_TRACING) += trace_printk.o
 obj-$(CONFIG_TRACING_MAP) += tracing_map.o
+obj-$(CONFIG_PREEMPTIRQ_DELAY_TEST) += preemptirq_delay_test.o
 obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
 obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o
-obj-$(CONFIG_PREEMPTIRQ_EVENTS) += trace_irqsoff.o
+obj-$(CONFIG_PREEMPTIRQ_TRACEPOINTS) += trace_preemptirq.o
 obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
 obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
 obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index b951aa1fac61..2a24a59e99c5 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2006 Jens Axboe <axboe@kernel.dk>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
  */
 #include <linux/kernel.h>
 #include <linux/blkdev.h>
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 0ae6829804bc..08fcfe440c63 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1,9 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
  * Copyright (c) 2016 Facebook
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
  */
 #include <linux/kernel.h>
 #include <linux/types.h>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index caf9cbf35816..f536f601bd46 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Infrastructure for profiling code inserted by 'gcc -pg'.
  *
@@ -157,30 +158,6 @@ static inline void ftrace_ops_init(struct ftrace_ops *ops)
 #endif
 }
 
-/**
- * ftrace_nr_registered_ops - return number of ops registered
- *
- * Returns the number of ftrace_ops registered and tracing functions
- */
-int ftrace_nr_registered_ops(void)
-{
-	struct ftrace_ops *ops;
-	int cnt = 0;
-
-	mutex_lock(&ftrace_lock);
-
-	for (ops = rcu_dereference_protected(ftrace_ops_list,
-					     lockdep_is_held(&ftrace_lock));
-	     ops != &ftrace_list_end;
-	     ops = rcu_dereference_protected(ops->next,
-					     lockdep_is_held(&ftrace_lock)))
-		cnt++;
-
-	mutex_unlock(&ftrace_lock);
-
-	return cnt;
-}
-
 static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
 			    struct ftrace_ops *op, struct pt_regs *regs)
 {
@@ -313,11 +290,6 @@ static void update_ftrace_function(void)
 	ftrace_trace_function = func;
 }
 
-int using_ftrace_ops_list_func(void)
-{
-	return ftrace_trace_function == ftrace_ops_list_func;
-}
-
 static void add_ftrace_ops(struct ftrace_ops __rcu **list,
 			   struct ftrace_ops *ops)
 {
@@ -1049,8 +1021,6 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
 }
 #endif /* CONFIG_FUNCTION_PROFILER */
 
-static struct pid * const ftrace_swapper_pid = &init_struct_pid;
-
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 static int ftrace_graph_active;
 #else
@@ -2927,22 +2897,22 @@ ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec)
 {
 	/* If ops isn't enabled, ignore it */
 	if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
-		return 0;
+		return false;
 
 	/* If ops traces all then it includes this function */
 	if (ops_traces_mod(ops))
-		return 1;
+		return true;
 
 	/* The function must be in the filter */
 	if (!ftrace_hash_empty(ops->func_hash->filter_hash) &&
 	    !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))
-		return 0;
+		return false;
 
 	/* If in notrace hash, we ignore it too */
 	if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip))
-		return 0;
+		return false;
 
-	return 1;
+	return true;
 }
 
 static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
@@ -2981,12 +2951,14 @@ static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
 			p = &pg->records[i];
 			p->flags = rec_flags;
 
+#ifndef CC_USING_NOP_MCOUNT
 			/*
 			 * Do the initial record conversion from mcount jump
 			 * to the NOP instructions.
 			 */
 			if (!ftrace_code_disable(mod, p))
 				break;
+#endif
 
 			update_cnt++;
 		}
diff --git a/kernel/trace/preemptirq_delay_test.c b/kernel/trace/preemptirq_delay_test.c
new file mode 100644
index 000000000000..f704390db9fc
--- /dev/null
+++ b/kernel/trace/preemptirq_delay_test.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Preempt / IRQ disable delay thread to test latency tracers
+ *
+ * Copyright (C) 2018 Joel Fernandes (Google) <joel@joelfernandes.org>
+ */
+
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/ktime.h>
+#include <linux/module.h>
+#include <linux/printk.h>
+#include <linux/string.h>
+
+static ulong delay = 100;
+static char test_mode[10] = "irq";
+
+module_param_named(delay, delay, ulong, S_IRUGO);
+module_param_string(test_mode, test_mode, 10, S_IRUGO);
+MODULE_PARM_DESC(delay, "Period in microseconds (100 uS default)");
+MODULE_PARM_DESC(test_mode, "Mode of the test such as preempt or irq (default irq)");
+
+static void busy_wait(ulong time)
+{
+	ktime_t start, end;
+	start = ktime_get();
+	do {
+		end = ktime_get();
+		if (kthread_should_stop())
+			break;
+	} while (ktime_to_ns(ktime_sub(end, start)) < (time * 1000));
+}
+
+static int preemptirq_delay_run(void *data)
+{
+	unsigned long flags;
+
+	if (!strcmp(test_mode, "irq")) {
+		local_irq_save(flags);
+		busy_wait(delay);
+		local_irq_restore(flags);
+	} else if (!strcmp(test_mode, "preempt")) {
+		preempt_disable();
+		busy_wait(delay);
+		preempt_enable();
+	}
+
+	return 0;
+}
+
+static int __init preemptirq_delay_init(void)
+{
+	char task_name[50];
+	struct task_struct *test_task;
+
+	snprintf(task_name, sizeof(task_name), "%s_test", test_mode);
+
+	test_task = kthread_run(preemptirq_delay_run, NULL, task_name);
+	return PTR_ERR_OR_ZERO(test_task);
+}
+
+static void __exit preemptirq_delay_exit(void)
+{
+	return;
+}
+
+module_init(preemptirq_delay_init)
+module_exit(preemptirq_delay_exit)
+MODULE_LICENSE("GPL v2");
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 0b0b688ea166..1d92d4a982fd 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Generic ring buffer
  *
@@ -3221,7 +3222,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_on);
  *
  * Returns true if the ring buffer is in a state that it accepts writes.
  */
-int ring_buffer_record_is_on(struct ring_buffer *buffer)
+bool ring_buffer_record_is_on(struct ring_buffer *buffer)
 {
 	return !atomic_read(&buffer->record_disabled);
 }
@@ -3237,7 +3238,7 @@ int ring_buffer_record_is_on(struct ring_buffer *buffer)
  * ring_buffer_record_disable(), as that is a temporary disabling of
  * the ring buffer.
  */
-int ring_buffer_record_is_set_on(struct ring_buffer *buffer)
+bool ring_buffer_record_is_set_on(struct ring_buffer *buffer)
 {
 	return !(atomic_read(&buffer->record_disabled) & RB_BUFFER_OFF);
 }
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index 68ee79afe31c..ffba6789c0e2 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * ring buffer tester and benchmark
  *
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 176debd3481b..bf6f1d70484d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * ring buffer based function tracer
  *
@@ -1087,7 +1088,7 @@ void disable_trace_on_warning(void)
  *
  * Shows real state of the ring buffer if it is enabled or not.
  */
-int tracer_tracing_is_on(struct trace_array *tr)
+bool tracer_tracing_is_on(struct trace_array *tr)
 {
 	if (tr->trace_buffer.buffer)
 		return ring_buffer_record_is_on(tr->trace_buffer.buffer);
@@ -7628,7 +7629,9 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
 
 	if (buffer) {
 		mutex_lock(&trace_types_lock);
-		if (val) {
+		if (!!val == tracer_tracing_is_on(tr)) {
+			val = 0; /* do nothing */
+		} else if (val) {
 			tracer_tracing_on(tr);
 			if (tr->current_trace->start)
 				tr->current_trace->start(tr);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index f8f86231ad90..3b8c0e24ab30 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 
 #ifndef _LINUX_KERNEL_TRACE_H
 #define _LINUX_KERNEL_TRACE_H
@@ -594,7 +594,7 @@ void tracing_reset_current(int cpu);
 void tracing_reset_all_online_cpus(void);
 int tracing_open_generic(struct inode *inode, struct file *filp);
 bool tracing_is_disabled(void);
-int tracer_tracing_is_on(struct trace_array *tr);
+bool tracer_tracing_is_on(struct trace_array *tr);
 void tracer_tracing_on(struct trace_array *tr);
 void tracer_tracing_off(struct trace_array *tr);
 struct dentry *trace_create_file(const char *name,
@@ -937,7 +937,6 @@ void ftrace_destroy_function_files(struct trace_array *tr);
 void ftrace_init_global_array_ops(struct trace_array *tr);
 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
 void ftrace_reset_array_ops(struct trace_array *tr);
-int using_ftrace_ops_list_func(void);
 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
 				  struct dentry *d_tracer);
@@ -1533,9 +1532,6 @@ extern int event_trigger_init(struct event_trigger_ops *ops,
 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
 					      int trigger_enable);
 extern void update_cond_flag(struct trace_event_file *file);
-extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
-			       struct event_trigger_data *test,
-			       struct trace_event_file *file);
 extern int set_trigger_filter(char *filter_str,
 			      struct event_trigger_data *trigger_data,
 			      struct trace_event_file *file);
@@ -1831,6 +1827,21 @@ static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
 }
 #endif
 
+#ifdef CONFIG_PREEMPT_TRACER
+void tracer_preempt_on(unsigned long a0, unsigned long a1);
+void tracer_preempt_off(unsigned long a0, unsigned long a1);
+#else
+static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
+static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
+#endif
+#ifdef CONFIG_IRQSOFF_TRACER
+void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
+void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
+#else
+static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
+static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
+#endif
+
 extern struct trace_iterator *tracepoint_print_iter;
 
 #endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_benchmark.h b/kernel/trace/trace_benchmark.h
index be1d86ff753d..79e6fbe5b365 100644
--- a/kernel/trace/trace_benchmark.h
+++ b/kernel/trace/trace_benchmark.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM benchmark
 
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index d8a188e0418a..aaf6793ededa 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * tracing clocks
  *
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index 1d67464ed95e..06bb2fd9a56c 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 /*
  * This file defines the trace event structures that go into the ring
  * buffer directly. They are created via macros so that changes for them
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index c79193e598f5..69a3fe926e8c 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace event based perf event profiling/tracing
  *
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 14ff4ff3caab..f94be0c2827b 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * event tracer
  *
@@ -239,7 +240,7 @@ bool trace_event_ignore_this_pid(struct trace_event_file *trace_file)
 	struct trace_array_cpu *data;
 	struct trace_pid_list *pid_list;
 
-	pid_list = rcu_dereference_sched(tr->filtered_pids);
+	pid_list = rcu_dereference_raw(tr->filtered_pids);
 	if (!pid_list)
 		return false;
 
@@ -512,7 +513,7 @@ event_filter_pid_sched_process_exit(void *data, struct task_struct *task)
 	struct trace_pid_list *pid_list;
 	struct trace_array *tr = data;
 
-	pid_list = rcu_dereference_sched(tr->filtered_pids);
+	pid_list = rcu_dereference_raw(tr->filtered_pids);
 	trace_filter_add_remove_task(pid_list, NULL, task);
 }
 
@@ -636,7 +637,7 @@ static void __ftrace_clear_event_pids(struct trace_array *tr)
 	rcu_assign_pointer(tr->filtered_pids, NULL);
 
 	/* Wait till all users are no longer using pid filtering */
-	synchronize_sched();
+	tracepoint_synchronize_unregister();
 
 	trace_free_pid_list(pid_list);
 }
@@ -1622,7 +1623,7 @@ ftrace_event_pid_write(struct file *filp, const char __user *ubuf,
 	}
 
 	if (filtered_pids) {
-		synchronize_sched();
+		tracepoint_synchronize_unregister();
 		trace_free_pid_list(filtered_pids);
 	} else if (pid_list) {
 		/*
@@ -3036,8 +3037,8 @@ int event_trace_del_tracer(struct trace_array *tr)
 	/* Disable any running events */
 	__ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
 
-	/* Access to events are within rcu_read_lock_sched() */
-	synchronize_sched();
+	/* Make sure no more events are being executed */
+	tracepoint_synchronize_unregister();
 
 	down_write(&trace_event_sem);
 	__trace_remove_event_dirs(tr);
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 893a206bcba4..84a65173b1e9 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -1,20 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_events_filter - generic event filtering
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
  * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
  */
 
@@ -899,7 +886,8 @@ int filter_match_preds(struct event_filter *filter, void *rec)
 	if (!filter)
 		return 1;
 
-	prog = rcu_dereference_sched(filter->prog);
+	/* Protected by either SRCU(tracepoint_srcu) or preempt_disable */
+	prog = rcu_dereference_raw(filter->prog);
 	if (!prog)
 		return 1;
 
@@ -1626,10 +1614,10 @@ static int process_system_preds(struct trace_subsystem_dir *dir,
 
 	/*
 	 * The calls can still be using the old filters.
-	 * Do a synchronize_sched() to ensure all calls are
+	 * Do a synchronize_sched() and to ensure all calls are
 	 * done with them before we free them.
 	 */
-	synchronize_sched();
+	tracepoint_synchronize_unregister();
 	list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
 		__free_filter(filter_item->filter);
 		list_del(&filter_item->list);
@@ -1648,7 +1636,7 @@ static int process_system_preds(struct trace_subsystem_dir *dir,
 	kfree(filter);
 	/* If any call succeeded, we still need to sync */
 	if (!fail)
-		synchronize_sched();
+		tracepoint_synchronize_unregister();
 	list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
 		__free_filter(filter_item->filter);
 		list_del(&filter_item->list);
@@ -1790,7 +1778,7 @@ int apply_event_filter(struct trace_event_file *file, char *filter_string)
 		event_clear_filter(file);
 
 		/* Make sure the filter is not being used */
-		synchronize_sched();
+		tracepoint_synchronize_unregister();
 		__free_filter(filter);
 
 		return 0;
@@ -1817,7 +1805,7 @@ int apply_event_filter(struct trace_event_file *file, char *filter_string)
 
 		if (tmp) {
 			/* Make sure the call is done with the filter */
-			synchronize_sched();
+			tracepoint_synchronize_unregister();
 			__free_filter(tmp);
 		}
 	}
@@ -1847,7 +1835,7 @@ int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
 		filter = system->filter;
 		system->filter = NULL;
 		/* Ensure all filters are no longer used */
-		synchronize_sched();
+		tracepoint_synchronize_unregister();
 		filter_free_subsystem_filters(dir, tr);
 		__free_filter(filter);
 		goto out_unlock;
diff --git a/kernel/trace/trace_events_filter_test.h b/kernel/trace/trace_events_filter_test.h
index 39d7ef4f57cb..e651dfbd345e 100644
--- a/kernel/trace/trace_events_filter_test.h
+++ b/kernel/trace/trace_events_filter_test.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM test
 
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index aae18af94c94..85f6b01431c7 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -1,16 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_events_hist - trace event hist triggers
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
  */
 
@@ -5141,7 +5132,7 @@ static void hist_clear(struct event_trigger_data *data)
 	if (data->name)
 		pause_named_trigger(data);
 
-	synchronize_sched();
+	tracepoint_synchronize_unregister();
 
 	tracing_map_clear(hist_data->map);
 
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 5dea177cef53..2152d1e530cb 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -1,20 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_events_trigger - trace event triggers
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
  * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com>
  */
 
@@ -34,7 +21,9 @@ void trigger_data_free(struct event_trigger_data *data)
 	if (data->cmd_ops->set_filter)
 		data->cmd_ops->set_filter(NULL, data, NULL);
 
-	synchronize_sched(); /* make sure current triggers exit before free */
+	/* make sure current triggers exit before free */
+	tracepoint_synchronize_unregister();
+
 	kfree(data);
 }
 
@@ -579,9 +568,9 @@ out:
  * Usually used directly as the @unreg method in event command
  * implementations.
  */
-void unregister_trigger(char *glob, struct event_trigger_ops *ops,
-			struct event_trigger_data *test,
-			struct trace_event_file *file)
+static void unregister_trigger(char *glob, struct event_trigger_ops *ops,
+			       struct event_trigger_data *test,
+			       struct trace_event_file *file)
 {
 	struct event_trigger_data *data;
 	bool unregistered = false;
@@ -752,7 +741,7 @@ int set_trigger_filter(char *filter_str,
 
 	if (tmp) {
 		/* Make sure the call is done with the filter */
-		synchronize_sched();
+		tracepoint_synchronize_unregister();
 		free_event_filter(tmp);
 	}
 
diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c
index d7c8e4ec3d9d..1e6db9cbe4dc 100644
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_hwlatdetect.c - A simple Hardware Latency detector.
  *
@@ -35,9 +36,6 @@
  *
  * Includes useful feedback from Clark Williams <clark@redhat.com>
  *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
  */
 #include <linux/kthread.h>
 #include <linux/tracefs.h>
@@ -354,6 +352,9 @@ static int start_kthread(struct trace_array *tr)
 	struct task_struct *kthread;
 	int next_cpu;
 
+	if (WARN_ON(hwlat_kthread))
+		return 0;
+
 	/* Just pick the first CPU on first iteration */
 	current_mask = &save_cpumask;
 	get_online_cpus();
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 03ecb4465ee4..b7357f9f82a3 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace irqs off critical timings
  *
@@ -16,7 +17,6 @@
 
 #include "trace.h"
 
-#define CREATE_TRACE_POINTS
 #include <trace/events/preemptirq.h>
 
 #if defined(CONFIG_IRQSOFF_TRACER) || defined(CONFIG_PREEMPT_TRACER)
@@ -41,12 +41,12 @@ static int start_irqsoff_tracer(struct trace_array *tr, int graph);
 
 #ifdef CONFIG_PREEMPT_TRACER
 static inline int
-preempt_trace(void)
+preempt_trace(int pc)
 {
-	return ((trace_type & TRACER_PREEMPT_OFF) && preempt_count());
+	return ((trace_type & TRACER_PREEMPT_OFF) && pc);
 }
 #else
-# define preempt_trace() (0)
+# define preempt_trace(pc) (0)
 #endif
 
 #ifdef CONFIG_IRQSOFF_TRACER
@@ -367,7 +367,7 @@ out:
 }
 
 static inline void
-start_critical_timing(unsigned long ip, unsigned long parent_ip)
+start_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 {
 	int cpu;
 	struct trace_array *tr = irqsoff_trace;
@@ -395,7 +395,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip)
 
 	local_save_flags(flags);
 
-	__trace_function(tr, ip, parent_ip, flags, preempt_count());
+	__trace_function(tr, ip, parent_ip, flags, pc);
 
 	per_cpu(tracing_cpu, cpu) = 1;
 
@@ -403,7 +403,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip)
 }
 
 static inline void
-stop_critical_timing(unsigned long ip, unsigned long parent_ip)
+stop_critical_timing(unsigned long ip, unsigned long parent_ip, int pc)
 {
 	int cpu;
 	struct trace_array *tr = irqsoff_trace;
@@ -429,7 +429,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip)
 	atomic_inc(&data->disabled);
 
 	local_save_flags(flags);
-	__trace_function(tr, ip, parent_ip, flags, preempt_count());
+	__trace_function(tr, ip, parent_ip, flags, pc);
 	check_critical_timing(tr, data, parent_ip ? : ip, cpu);
 	data->critical_start = 0;
 	atomic_dec(&data->disabled);
@@ -438,77 +438,21 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip)
 /* start and stop critical timings used to for stoppage (in idle) */
 void start_critical_timings(void)
 {
-	if (preempt_trace() || irq_trace())
-		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+	int pc = preempt_count();
+
+	if (preempt_trace(pc) || irq_trace())
+		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
 }
 EXPORT_SYMBOL_GPL(start_critical_timings);
 
 void stop_critical_timings(void)
 {
-	if (preempt_trace() || irq_trace())
-		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
-}
-EXPORT_SYMBOL_GPL(stop_critical_timings);
-
-#ifdef CONFIG_IRQSOFF_TRACER
-#ifdef CONFIG_PROVE_LOCKING
-void time_hardirqs_on(unsigned long a0, unsigned long a1)
-{
-	if (!preempt_trace() && irq_trace())
-		stop_critical_timing(a0, a1);
-}
-
-void time_hardirqs_off(unsigned long a0, unsigned long a1)
-{
-	if (!preempt_trace() && irq_trace())
-		start_critical_timing(a0, a1);
-}
-
-#else /* !CONFIG_PROVE_LOCKING */
-
-/*
- * We are only interested in hardirq on/off events:
- */
-static inline void tracer_hardirqs_on(void)
-{
-	if (!preempt_trace() && irq_trace())
-		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
-}
+	int pc = preempt_count();
 
-static inline void tracer_hardirqs_off(void)
-{
-	if (!preempt_trace() && irq_trace())
-		start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
-}
-
-static inline void tracer_hardirqs_on_caller(unsigned long caller_addr)
-{
-	if (!preempt_trace() && irq_trace())
-		stop_critical_timing(CALLER_ADDR0, caller_addr);
-}
-
-static inline void tracer_hardirqs_off_caller(unsigned long caller_addr)
-{
-	if (!preempt_trace() && irq_trace())
-		start_critical_timing(CALLER_ADDR0, caller_addr);
-}
-
-#endif /* CONFIG_PROVE_LOCKING */
-#endif /*  CONFIG_IRQSOFF_TRACER */
-
-#ifdef CONFIG_PREEMPT_TRACER
-static inline void tracer_preempt_on(unsigned long a0, unsigned long a1)
-{
-	if (preempt_trace() && !irq_trace())
-		stop_critical_timing(a0, a1);
-}
-
-static inline void tracer_preempt_off(unsigned long a0, unsigned long a1)
-{
-	if (preempt_trace() && !irq_trace())
-		start_critical_timing(a0, a1);
+	if (preempt_trace(pc) || irq_trace())
+		stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1, pc);
 }
-#endif /* CONFIG_PREEMPT_TRACER */
+EXPORT_SYMBOL_GPL(stop_critical_timings);
 
 #ifdef CONFIG_FUNCTION_TRACER
 static bool function_enabled;
@@ -634,7 +578,7 @@ static int __irqsoff_tracer_init(struct trace_array *tr)
 	return 0;
 }
 
-static void irqsoff_tracer_reset(struct trace_array *tr)
+static void __irqsoff_tracer_reset(struct trace_array *tr)
 {
 	int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT;
 	int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE;
@@ -659,12 +603,37 @@ static void irqsoff_tracer_stop(struct trace_array *tr)
 }
 
 #ifdef CONFIG_IRQSOFF_TRACER
+/*
+ * We are only interested in hardirq on/off events:
+ */
+void tracer_hardirqs_on(unsigned long a0, unsigned long a1)
+{
+	unsigned int pc = preempt_count();
+
+	if (!preempt_trace(pc) && irq_trace())
+		stop_critical_timing(a0, a1, pc);
+}
+
+void tracer_hardirqs_off(unsigned long a0, unsigned long a1)
+{
+	unsigned int pc = preempt_count();
+
+	if (!preempt_trace(pc) && irq_trace())
+		start_critical_timing(a0, a1, pc);
+}
+
 static int irqsoff_tracer_init(struct trace_array *tr)
 {
 	trace_type = TRACER_IRQS_OFF;
 
 	return __irqsoff_tracer_init(tr);
 }
+
+static void irqsoff_tracer_reset(struct trace_array *tr)
+{
+	__irqsoff_tracer_reset(tr);
+}
+
 static struct tracer irqsoff_tracer __read_mostly =
 {
 	.name		= "irqsoff",
@@ -684,12 +653,25 @@ static struct tracer irqsoff_tracer __read_mostly =
 	.allow_instances = true,
 	.use_max_tr	= true,
 };
-# define register_irqsoff(trace) register_tracer(&trace)
-#else
-# define register_irqsoff(trace) do { } while (0)
-#endif
+#endif /*  CONFIG_IRQSOFF_TRACER */
 
 #ifdef CONFIG_PREEMPT_TRACER
+void tracer_preempt_on(unsigned long a0, unsigned long a1)
+{
+	int pc = preempt_count();
+
+	if (preempt_trace(pc) && !irq_trace())
+		stop_critical_timing(a0, a1, pc);
+}
+
+void tracer_preempt_off(unsigned long a0, unsigned long a1)
+{
+	int pc = preempt_count();
+
+	if (preempt_trace(pc) && !irq_trace())
+		start_critical_timing(a0, a1, pc);
+}
+
 static int preemptoff_tracer_init(struct trace_array *tr)
 {
 	trace_type = TRACER_PREEMPT_OFF;
@@ -697,11 +679,16 @@ static int preemptoff_tracer_init(struct trace_array *tr)
 	return __irqsoff_tracer_init(tr);
 }
 
+static void preemptoff_tracer_reset(struct trace_array *tr)
+{
+	__irqsoff_tracer_reset(tr);
+}
+
 static struct tracer preemptoff_tracer __read_mostly =
 {
 	.name		= "preemptoff",
 	.init		= preemptoff_tracer_init,
-	.reset		= irqsoff_tracer_reset,
+	.reset		= preemptoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
 	.print_max	= true,
@@ -716,13 +703,9 @@ static struct tracer preemptoff_tracer __read_mostly =
 	.allow_instances = true,
 	.use_max_tr	= true,
 };
-# define register_preemptoff(trace) register_tracer(&trace)
-#else
-# define register_preemptoff(trace) do { } while (0)
-#endif
+#endif /* CONFIG_PREEMPT_TRACER */
 
-#if defined(CONFIG_IRQSOFF_TRACER) && \
-	defined(CONFIG_PREEMPT_TRACER)
+#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
 
 static int preemptirqsoff_tracer_init(struct trace_array *tr)
 {
@@ -731,11 +714,16 @@ static int preemptirqsoff_tracer_init(struct trace_array *tr)
 	return __irqsoff_tracer_init(tr);
 }
 
+static void preemptirqsoff_tracer_reset(struct trace_array *tr)
+{
+	__irqsoff_tracer_reset(tr);
+}
+
 static struct tracer preemptirqsoff_tracer __read_mostly =
 {
 	.name		= "preemptirqsoff",
 	.init		= preemptirqsoff_tracer_init,
-	.reset		= irqsoff_tracer_reset,
+	.reset		= preemptirqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
 	.print_max	= true,
@@ -750,115 +738,21 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
 	.allow_instances = true,
 	.use_max_tr	= true,
 };
-
-# define register_preemptirqsoff(trace) register_tracer(&trace)
-#else
-# define register_preemptirqsoff(trace) do { } while (0)
 #endif
 
 __init static int init_irqsoff_tracer(void)
 {
-	register_irqsoff(irqsoff_tracer);
-	register_preemptoff(preemptoff_tracer);
-	register_preemptirqsoff(preemptirqsoff_tracer);
-
-	return 0;
-}
-core_initcall(init_irqsoff_tracer);
-#endif /* IRQSOFF_TRACER || PREEMPTOFF_TRACER */
-
-#ifndef CONFIG_IRQSOFF_TRACER
-static inline void tracer_hardirqs_on(void) { }
-static inline void tracer_hardirqs_off(void) { }
-static inline void tracer_hardirqs_on_caller(unsigned long caller_addr) { }
-static inline void tracer_hardirqs_off_caller(unsigned long caller_addr) { }
+#ifdef CONFIG_IRQSOFF_TRACER
+	register_tracer(&irqsoff_tracer);
 #endif
-
-#ifndef CONFIG_PREEMPT_TRACER
-static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
-static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
+#ifdef CONFIG_PREEMPT_TRACER
+	register_tracer(&preemptoff_tracer);
 #endif
-
-#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PROVE_LOCKING)
-/* Per-cpu variable to prevent redundant calls when IRQs already off */
-static DEFINE_PER_CPU(int, tracing_irq_cpu);
-
-void trace_hardirqs_on(void)
-{
-	if (!this_cpu_read(tracing_irq_cpu))
-		return;
-
-	trace_irq_enable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
-	tracer_hardirqs_on();
-
-	this_cpu_write(tracing_irq_cpu, 0);
-}
-EXPORT_SYMBOL(trace_hardirqs_on);
-
-void trace_hardirqs_off(void)
-{
-	if (this_cpu_read(tracing_irq_cpu))
-		return;
-
-	this_cpu_write(tracing_irq_cpu, 1);
-
-	trace_irq_disable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
-	tracer_hardirqs_off();
-}
-EXPORT_SYMBOL(trace_hardirqs_off);
-
-__visible void trace_hardirqs_on_caller(unsigned long caller_addr)
-{
-	if (!this_cpu_read(tracing_irq_cpu))
-		return;
-
-	trace_irq_enable_rcuidle(CALLER_ADDR0, caller_addr);
-	tracer_hardirqs_on_caller(caller_addr);
-
-	this_cpu_write(tracing_irq_cpu, 0);
-}
-EXPORT_SYMBOL(trace_hardirqs_on_caller);
-
-__visible void trace_hardirqs_off_caller(unsigned long caller_addr)
-{
-	if (this_cpu_read(tracing_irq_cpu))
-		return;
-
-	this_cpu_write(tracing_irq_cpu, 1);
-
-	trace_irq_disable_rcuidle(CALLER_ADDR0, caller_addr);
-	tracer_hardirqs_off_caller(caller_addr);
-}
-EXPORT_SYMBOL(trace_hardirqs_off_caller);
-
-/*
- * Stubs:
- */
-
-void trace_softirqs_on(unsigned long ip)
-{
-}
-
-void trace_softirqs_off(unsigned long ip)
-{
-}
-
-inline void print_irqtrace_events(struct task_struct *curr)
-{
-}
+#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
+	register_tracer(&preemptirqsoff_tracer);
 #endif
 
-#if defined(CONFIG_PREEMPT_TRACER) || \
-	(defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_PREEMPTIRQ_EVENTS))
-void trace_preempt_on(unsigned long a0, unsigned long a1)
-{
-	trace_preempt_enable_rcuidle(a0, a1);
-	tracer_preempt_on(a0, a1);
-}
-
-void trace_preempt_off(unsigned long a0, unsigned long a1)
-{
-	trace_preempt_disable_rcuidle(a0, a1);
-	tracer_preempt_off(a0, a1);
+	return 0;
 }
-#endif
+core_initcall(init_irqsoff_tracer);
+#endif /* IRQSOFF_TRACER || PREEMPTOFF_TRACER */
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index e9d99463e5df..2bfb2bbeb3d2 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1,20 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Kprobes-based tracing events
  *
  * Created by Masami Hiramatsu <mhiramat@redhat.com>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 #define pr_fmt(fmt)	"trace_kprobe: " fmt
 
@@ -23,6 +12,7 @@
 #include <linux/rculist.h>
 #include <linux/error-injection.h>
 
+#include "trace_kprobe_selftest.h"
 #include "trace_probe.h"
 
 #define KPROBE_EVENT_SYSTEM "kprobes"
@@ -87,6 +77,23 @@ static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe *tk)
 	return nhit;
 }
 
+/* Return 0 if it fails to find the symbol address */
+static nokprobe_inline
+unsigned long trace_kprobe_address(struct trace_kprobe *tk)
+{
+	unsigned long addr;
+
+	if (tk->symbol) {
+		addr = (unsigned long)
+			kallsyms_lookup_name(trace_kprobe_symbol(tk));
+		if (addr)
+			addr += tk->rp.kp.offset;
+	} else {
+		addr = (unsigned long)tk->rp.kp.addr;
+	}
+	return addr;
+}
+
 bool trace_kprobe_on_func_entry(struct trace_event_call *call)
 {
 	struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
@@ -99,16 +106,8 @@ bool trace_kprobe_on_func_entry(struct trace_event_call *call)
 bool trace_kprobe_error_injectable(struct trace_event_call *call)
 {
 	struct trace_kprobe *tk = (struct trace_kprobe *)call->data;
-	unsigned long addr;
 
-	if (tk->symbol) {
-		addr = (unsigned long)
-			kallsyms_lookup_name(trace_kprobe_symbol(tk));
-		addr += tk->rp.kp.offset;
-	} else {
-		addr = (unsigned long)tk->rp.kp.addr;
-	}
-	return within_error_injection_list(addr);
+	return within_error_injection_list(trace_kprobe_address(tk));
 }
 
 static int register_kprobe_event(struct trace_kprobe *tk);
@@ -393,6 +392,20 @@ static struct trace_kprobe *find_trace_kprobe(const char *event,
 	return NULL;
 }
 
+static inline int __enable_trace_kprobe(struct trace_kprobe *tk)
+{
+	int ret = 0;
+
+	if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {
+		if (trace_kprobe_is_return(tk))
+			ret = enable_kretprobe(&tk->rp);
+		else
+			ret = enable_kprobe(&tk->rp.kp);
+	}
+
+	return ret;
+}
+
 /*
  * Enable trace_probe
  * if the file is NULL, enable "perf" handler, or enable "trace" handler.
@@ -400,7 +413,7 @@ static struct trace_kprobe *find_trace_kprobe(const char *event,
 static int
 enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
 {
-	struct event_file_link *link = NULL;
+	struct event_file_link *link;
 	int ret = 0;
 
 	if (file) {
@@ -414,26 +427,18 @@ enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
 		list_add_tail_rcu(&link->list, &tk->tp.files);
 
 		tk->tp.flags |= TP_FLAG_TRACE;
-	} else
-		tk->tp.flags |= TP_FLAG_PROFILE;
-
-	if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) {
-		if (trace_kprobe_is_return(tk))
-			ret = enable_kretprobe(&tk->rp);
-		else
-			ret = enable_kprobe(&tk->rp.kp);
-	}
-
-	if (ret) {
-		if (file) {
-			/* Notice the if is true on not WARN() */
-			if (!WARN_ON_ONCE(!link))
-				list_del_rcu(&link->list);
+		ret = __enable_trace_kprobe(tk);
+		if (ret) {
+			list_del_rcu(&link->list);
 			kfree(link);
 			tk->tp.flags &= ~TP_FLAG_TRACE;
-		} else {
-			tk->tp.flags &= ~TP_FLAG_PROFILE;
 		}
+
+	} else {
+		tk->tp.flags |= TP_FLAG_PROFILE;
+		ret = __enable_trace_kprobe(tk);
+		if (ret)
+			tk->tp.flags &= ~TP_FLAG_PROFILE;
 	}
  out:
 	return ret;
@@ -498,6 +503,22 @@ disable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file)
 	return ret;
 }
 
+#if defined(CONFIG_KPROBES_ON_FTRACE) && \
+	!defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE)
+static bool within_notrace_func(struct trace_kprobe *tk)
+{
+	unsigned long offset, size, addr;
+
+	addr = trace_kprobe_address(tk);
+	if (!addr || !kallsyms_lookup_size_offset(addr, &size, &offset))
+		return false;
+
+	return !ftrace_location_range(addr - offset, addr - offset + size);
+}
+#else
+#define within_notrace_func(tk)	(false)
+#endif
+
 /* Internal register function - just handle k*probes and flags */
 static int __register_trace_kprobe(struct trace_kprobe *tk)
 {
@@ -506,6 +527,12 @@ static int __register_trace_kprobe(struct trace_kprobe *tk)
 	if (trace_probe_is_registered(&tk->tp))
 		return -EINVAL;
 
+	if (within_notrace_func(tk)) {
+		pr_warn("Could not probe notrace function %s\n",
+			trace_kprobe_symbol(tk));
+		return -EINVAL;
+	}
+
 	for (i = 0; i < tk->tp.nr_args; i++)
 		traceprobe_update_arg(&tk->tp.args[i]);
 
@@ -1547,17 +1574,6 @@ fs_initcall(init_kprobe_trace);
 
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
-/*
- * The "__used" keeps gcc from removing the function symbol
- * from the kallsyms table. 'noinline' makes sure that there
- * isn't an inlined version used by the test method below
- */
-static __used __init noinline int
-kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6)
-{
-	return a1 + a2 + a3 + a4 + a5 + a6;
-}
-
 static __init struct trace_event_file *
 find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr)
 {
diff --git a/kernel/trace/trace_kprobe_selftest.c b/kernel/trace/trace_kprobe_selftest.c
new file mode 100644
index 000000000000..16548ee4c8c6
--- /dev/null
+++ b/kernel/trace/trace_kprobe_selftest.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Function used during the kprobe self test. This function is in a separate
+ * compile unit so it can be compile with CC_FLAGS_FTRACE to ensure that it
+ * can be probed by the selftests.
+ */
+int kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6)
+{
+	return a1 + a2 + a3 + a4 + a5 + a6;
+}
diff --git a/kernel/trace/trace_kprobe_selftest.h b/kernel/trace/trace_kprobe_selftest.h
new file mode 100644
index 000000000000..c4fc7268ba7c
--- /dev/null
+++ b/kernel/trace/trace_kprobe_selftest.h
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Function used during the kprobe self test. This function is in a separate
+ * compile unit so it can be compile with CC_FLAGS_FTRACE to ensure that it
+ * can be probed by the selftests.
+ */
+int kprobe_trace_selftest_target(int a1, int a2, int a3, int a4, int a5, int a6);
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 1c8e30fda46a..6e6cc64faa38 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_output.c
  *
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index dbba03ed96de..2f742b74e7e6 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 #ifndef __TRACE_EVENTS_H
 #define __TRACE_EVENTS_H
 
diff --git a/kernel/trace/trace_preemptirq.c b/kernel/trace/trace_preemptirq.c
new file mode 100644
index 000000000000..71f553cceb3c
--- /dev/null
+++ b/kernel/trace/trace_preemptirq.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * preemptoff and irqoff tracepoints
+ *
+ * Copyright (C) Joel Fernandes (Google) <joel@joelfernandes.org>
+ */
+
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/ftrace.h>
+#include "trace.h"
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/preemptirq.h>
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+/* Per-cpu variable to prevent redundant calls when IRQs already off */
+static DEFINE_PER_CPU(int, tracing_irq_cpu);
+
+void trace_hardirqs_on(void)
+{
+	if (this_cpu_read(tracing_irq_cpu)) {
+		if (!in_nmi())
+			trace_irq_enable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
+		tracer_hardirqs_on(CALLER_ADDR0, CALLER_ADDR1);
+		this_cpu_write(tracing_irq_cpu, 0);
+	}
+
+	lockdep_hardirqs_on(CALLER_ADDR0);
+}
+EXPORT_SYMBOL(trace_hardirqs_on);
+
+void trace_hardirqs_off(void)
+{
+	if (!this_cpu_read(tracing_irq_cpu)) {
+		this_cpu_write(tracing_irq_cpu, 1);
+		tracer_hardirqs_off(CALLER_ADDR0, CALLER_ADDR1);
+		if (!in_nmi())
+			trace_irq_disable_rcuidle(CALLER_ADDR0, CALLER_ADDR1);
+	}
+
+	lockdep_hardirqs_off(CALLER_ADDR0);
+}
+EXPORT_SYMBOL(trace_hardirqs_off);
+
+__visible void trace_hardirqs_on_caller(unsigned long caller_addr)
+{
+	if (this_cpu_read(tracing_irq_cpu)) {
+		if (!in_nmi())
+			trace_irq_enable_rcuidle(CALLER_ADDR0, caller_addr);
+		tracer_hardirqs_on(CALLER_ADDR0, caller_addr);
+		this_cpu_write(tracing_irq_cpu, 0);
+	}
+
+	lockdep_hardirqs_on(CALLER_ADDR0);
+}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+
+__visible void trace_hardirqs_off_caller(unsigned long caller_addr)
+{
+	if (!this_cpu_read(tracing_irq_cpu)) {
+		this_cpu_write(tracing_irq_cpu, 1);
+		tracer_hardirqs_off(CALLER_ADDR0, caller_addr);
+		if (!in_nmi())
+			trace_irq_disable_rcuidle(CALLER_ADDR0, caller_addr);
+	}
+
+	lockdep_hardirqs_off(CALLER_ADDR0);
+}
+EXPORT_SYMBOL(trace_hardirqs_off_caller);
+#endif /* CONFIG_TRACE_IRQFLAGS */
+
+#ifdef CONFIG_TRACE_PREEMPT_TOGGLE
+
+void trace_preempt_on(unsigned long a0, unsigned long a1)
+{
+	if (!in_nmi())
+		trace_preempt_enable_rcuidle(a0, a1);
+	tracer_preempt_on(a0, a1);
+}
+
+void trace_preempt_off(unsigned long a0, unsigned long a1)
+{
+	if (!in_nmi())
+		trace_preempt_disable_rcuidle(a0, a1);
+	tracer_preempt_off(a0, a1);
+}
+#endif
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 50f44b7b2b32..b0875b327f5c 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace binary printk
  *
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index daf54bda4dc8..e99c3ce7aa65 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Common code for probe-based Dynamic events.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
  * This code was copied from kernel/trace/trace_kprobe.c written by
  * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
  *
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 75daff22ccea..5f52668e165d 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Common header file for probe-based Dynamic events.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
  * This code was copied from kernel/trace/trace_kprobe.h written by
  * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
  *
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c
index e694c9f9efa4..6b1c562ffdaf 100644
--- a/kernel/trace/trace_seq.c
+++ b/kernel/trace/trace_seq.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_seq.c
  *
diff --git a/kernel/trace/trace_stat.h b/kernel/trace/trace_stat.h
index 76d30b4ebe83..8786d17caf49 100644
--- a/kernel/trace/trace_stat.h
+++ b/kernel/trace/trace_stat.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 #ifndef __TRACE_STAT_H
 #define __TRACE_STAT_H
 
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index bf89a51e740d..e696667da29a 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * uprobes-based tracing events
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
  * Copyright (C) IBM Corporation, 2010-2012
  * Author:	Srikar Dronamraju <srikar@linux.vnet.ibm.com>
  */
@@ -952,7 +940,7 @@ probe_event_disable(struct trace_uprobe *tu, struct trace_event_file *file)
 
 		list_del_rcu(&link->list);
 		/* synchronize with u{,ret}probe_trace_func */
-		synchronize_sched();
+		synchronize_rcu();
 		kfree(link);
 
 		if (!list_empty(&tu->tp.files))
diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c
index 752d8042bad4..9a1c22310323 100644
--- a/kernel/trace/tracing_map.c
+++ b/kernel/trace/tracing_map.c
@@ -1,16 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * tracing_map - lock-free map for tracing
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
  *
  * tracing_map implementation inspired by lock-free map algorithms
diff --git a/kernel/trace/tracing_map.h b/kernel/trace/tracing_map.h
index 053eb92b2d31..a6de61fc22de 100644
--- a/kernel/trace/tracing_map.h
+++ b/kernel/trace/tracing_map.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+// SPDX-License-Identifier: GPL-2.0
 #ifndef __TRACING_MAP_H
 #define __TRACING_MAP_H