Merge tag 'trace-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
"The majority of the changes are for fixes and clean ups.

Notable changes:

- Rework trace event triggers code to be easier to interact with.

- Support for embedding bootconfig with the kernel (as suppose to
having it embedded in initram). This is useful for embedded boards
without initram disks.

- Speed up boot by parallelizing the creation of tracefs files.

- Allow absolute ring buffer timestamps handle timestamps that use
more than 59 bits.

- Added new tracing clock "TAI" (International Atomic Time)

- Have weak functions show up in available_filter_function list as:
__ftrace_invalid_address___<invalid-offset> instead of using the
name of the function before it"

* tag 'trace-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (52 commits)
ftrace: Add FTRACE_MCOUNT_MAX_OFFSET to avoid adding weak function
tracing: Fix comments for event_trigger_separate_filter()
x86/traceponit: Fix comment about irq vector tracepoints
x86,tracing: Remove unused headers
ftrace: Clean up hash direct_functions on register failures
tracing: Fix comments of create_filter()
tracing: Disable kcov on trace_preemptirq.c
tracing: Initialize integer variable to prevent garbage return value
ftrace: Fix typo in comment
ftrace: Remove return value of ftrace_arch_modify_*()
tracing: Cleanup code by removing init "char *name"
tracing: Change "char *" string form to "char []"
tracing/timerlat: Do not wakeup the thread if the trace stops at the IRQ
tracing/timerlat: Print stacktrace in the IRQ handler if needed
tracing/timerlat: Notify IRQ new max latency only if stop tracing is set
kprobes: Fix build errors with CONFIG_KRETPROBES=n
tracing: Fix return value of trace_pid_write()
tracing: Fix potential double free in create_var_ref()
tracing: Use strim() to remove whitespace instead of doing it manually
ftrace: Deal with error return code of the ftrace_process_locs() function
...

Documentation/admin-guide/bootconfig.rst

···
 Boot Kernel With a Boot Config
 ==============================
 
-Since the boot configuration file is loaded with initrd, it will be added
-to the end of the initrd (initramfs) image file with padding, size,
-checksum and 12-byte magic word as below.
+There are two options to boot the kernel with bootconfig: attaching the
+bootconfig to the initrd image or embedding it in the kernel itself.
+
+Attaching a Boot Config to Initrd
+---------------------------------
+
+Since the boot configuration file is loaded with initrd by default,
+it will be added to the end of the initrd (initramfs) image file with
+padding, size, checksum and 12-byte magic word as below.
 
 [initrd][bootconfig][padding][size(le32)][checksum(le32)][#BOOTCONFIG\n]
 
···
 Then add "bootconfig" on the normal kernel command line to tell the
 kernel to look for the bootconfig at the end of the initrd file.
 
+Embedding a Boot Config into Kernel
+-----------------------------------
+
+If you can not use initrd, you can also embed the bootconfig file in the
+kernel by Kconfig options. In this case, you need to recompile the kernel
+with the following configs::
+
+ CONFIG_BOOT_CONFIG_EMBED=y
+ CONFIG_BOOT_CONFIG_EMBED_FILE="/PATH/TO/BOOTCONFIG/FILE"
+
+``CONFIG_BOOT_CONFIG_EMBED_FILE`` requires an absolute path or a relative
+path to the bootconfig file from source tree or object tree.
+The kernel will embed it as the default bootconfig.
+
+Just as when attaching the bootconfig to the initrd, you need ``bootconfig``
+option on the kernel command line to enable the embedded bootconfig.
+
+Note that even if you set this option, you can override the embedded
+bootconfig by another bootconfig which attached to the initrd.
 
 Kernel parameters via Boot Config
 =================================

Documentation/trace/ftrace.rst

···
 		processing should be able to handle them. See comments in the
 		ktime_get_boot_fast_ns() function for more information.
 
+	tai:
+		This is the tai clock (CLOCK_TAI) and is derived from the wall-
+		clock time. However, this clock does not experience
+		discontinuities and backwards jumps caused by NTP inserting leap
+		seconds. Since the clock access is designed for use in tracing,
+		side effects are possible. The clock access may yield wrong
+		readouts in case the internal TAI offset is updated e.g., caused
+		by setting the system time or using adjtimex() with an offset.
+		These effects are rare and post processing should be able to
+		handle them. See comments in the ktime_get_tai_fast_ns()
+		function for more information.
+
 	To set a clock, simply echo the clock name into this file::
 
 	  # echo global > trace_clock

Documentation/trace/timerlat-tracer.rst

···
  - stop_tracing_total_us: stop the system tracing if a
    timer latency at the *thread* context is higher than the configured
    value happens. Writing 0 disables this option.
- - print_stack: save the stack of the IRQ occurrence, and print
-   it after the *thread context* event".
+ - print_stack: save the stack of the IRQ occurrence. The stack is printed
+   after the *thread context* event, or at the IRQ handler if *stop_tracing_us*
+   is hit.
 
 timerlat and osnoise
 ----------------------------

MAINTAINERS

···
 F:	Documentation/admin-guide/bootconfig.rst
 F:	fs/proc/bootconfig.c
 F:	include/linux/bootconfig.h
+F:	lib/bootconfig-data.S
 F:	lib/bootconfig.c
 F:	tools/bootconfig/*
 F:	tools/bootconfig/scripts/*
···
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
 F:	Documentation/trace/ftrace.rst
-F:	arch/*/*/*/ftrace.h
-F:	arch/*/kernel/ftrace.c
+F:	arch/*/*/*/*ftrace*
+F:	arch/*/*/*ftrace*
 F:	fs/tracefs/
 F:	include/*/ftrace.h
 F:	include/linux/trace*.h

arch/arm/kernel/ftrace.c

···
 	return (unsigned long)&ftrace_regs_caller_from_init;
 }
 
-int ftrace_arch_code_modify_prepare(void)
+void ftrace_arch_code_modify_prepare(void)
 {
-	return 0;
 }
 
-int ftrace_arch_code_modify_post_process(void)
+void ftrace_arch_code_modify_post_process(void)
 {
 	/* Make sure any TLB misses during machine stop are cleared. */
 	flush_tlb_all();
-	return 0;
 }
 
 static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr,

arch/riscv/kernel/ftrace.c

···
 #include <asm/patch.h>
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-int ftrace_arch_code_modify_prepare(void) __acquires(&text_mutex)
+void ftrace_arch_code_modify_prepare(void) __acquires(&text_mutex)
 {
 	mutex_lock(&text_mutex);
-	return 0;
 }
 
-int ftrace_arch_code_modify_post_process(void) __releases(&text_mutex)
+void ftrace_arch_code_modify_post_process(void) __releases(&text_mutex)
 {
 	mutex_unlock(&text_mutex);
-	return 0;
 }
 
 static int ftrace_check_current_call(unsigned long hook_pos,

arch/s390/kernel/ftrace.c

···
 	ftrace_modify_all_code(command);
 }
 
-int ftrace_arch_code_modify_post_process(void)
+void ftrace_arch_code_modify_post_process(void)
 {
 	/*
 	 * Flush any pre-fetched instructions on all
 	 * CPUs to make the new code visible.
 	 */
 	text_poke_sync_lock();
-	return 0;
 }
 
 #ifdef CONFIG_MODULES

arch/x86/include/asm/ftrace.h

···
 # define MCOUNT_ADDR		((unsigned long)(__fentry__))
 #define MCOUNT_INSN_SIZE	5 /* sizeof mcount call */
 
+/* Ignore unused weak functions which will have non zero offsets */
+#ifdef CONFIG_HAVE_FENTRY
+# include <asm/ibt.h>
+/* Add offset for endbr64 if IBT enabled */
+# define FTRACE_MCOUNT_MAX_OFFSET	ENDBR_INSN_SIZE
+#endif
+
 #ifdef CONFIG_DYNAMIC_FTRACE
 #define ARCH_SUPPORTS_FTRACE_OPS 1
 #endif

arch/x86/kernel/ftrace.c

···
 
 static int ftrace_poke_late = 0;
 
-int ftrace_arch_code_modify_prepare(void)
+void ftrace_arch_code_modify_prepare(void)
     __acquires(&text_mutex)
 {
 	/*
···
 	 */
 	mutex_lock(&text_mutex);
 	ftrace_poke_late = 1;
-	return 0;
 }
 
-int ftrace_arch_code_modify_post_process(void)
+void ftrace_arch_code_modify_post_process(void)
     __releases(&text_mutex)
 {
 	/*
···
 	text_poke_finish();
 	ftrace_poke_late = 0;
 	mutex_unlock(&text_mutex);
-	return 0;
 }
 
 static const char *ftrace_nop_replace(void)

arch/x86/kernel/tracepoint.c

···
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Code for supporting irq vector tracepoints.
- *
  * Copyright (C) 2013 Seiji Aguchi <[e-mail]>
- *
  */
 #include <linux/jump_label.h>
 #include <linux/atomic.h>
 
-#include <asm/hw_irq.h>
-#include <asm/desc.h>
 #include <asm/trace/exceptions.h>
-#include <asm/trace/irq_vectors.h>
 
 DEFINE_STATIC_KEY_FALSE(trace_pagefault_key);
 

include/linux/bootconfig.h

···
 /* XBC cleanup data structures */
 void __init xbc_exit(void);
 
+/* XBC embedded bootconfig data in kernel */
+#ifdef CONFIG_BOOT_CONFIG_EMBED
+const char * __init xbc_get_embedded_bootconfig(size_t *size);
+#else
+static inline const char *xbc_get_embedded_bootconfig(size_t *size)
+{
+	return NULL;
+}
+#endif
+
 #endif

include/linux/ftrace.h

···
 
 #ifdef CONFIG_DYNAMIC_FTRACE
 
-int ftrace_arch_code_modify_prepare(void);
-int ftrace_arch_code_modify_post_process(void);
+void ftrace_arch_code_modify_prepare(void);
+void ftrace_arch_code_modify_post_process(void);
 
 enum ftrace_bug_type {
 	FTRACE_BUG_UNKNOWN,

include/linux/kprobes.h

···
 int register_kretprobes(struct kretprobe **rps, int num);
 void unregister_kretprobes(struct kretprobe **rps, int num);
 
-#ifdef CONFIG_KRETPROBE_ON_RETHOOK
+#if defined(CONFIG_KRETPROBE_ON_RETHOOK) || !defined(CONFIG_KRETPROBES)
 #define kprobe_flush_task(tk)	do {} while (0)
 #else
 void kprobe_flush_task(struct task_struct *tk);

init/Kconfig

···
 
 config BOOT_CONFIG
 	bool "Boot config support"
-	select BLK_DEV_INITRD
+	select BLK_DEV_INITRD if !BOOT_CONFIG_EMBED
 	help
 	  Extra boot config allows system admin to pass a config file as
 	  complemental extension of kernel cmdline when booting.
···
 	  See <file:Documentation/admin-guide/bootconfig.rst> for details.
 
 	  If unsure, say Y.
+
+config BOOT_CONFIG_EMBED
+	bool "Embed bootconfig file in the kernel"
+	depends on BOOT_CONFIG
+	help
+	  Embed a bootconfig file given by BOOT_CONFIG_EMBED_FILE in the
+	  kernel. Usually, the bootconfig file is loaded with the initrd
+	  image. But if the system doesn't support initrd, this option will
+	  help you by embedding a bootconfig file while building the kernel.
+
+	  If unsure, say N.
+
+config BOOT_CONFIG_EMBED_FILE
+	string "Embedded bootconfig file path"
+	depends on BOOT_CONFIG_EMBED
+	help
+	  Specify a bootconfig file which will be embedded to the kernel.
+	  This bootconfig will be used if there is no initrd or no other
+	  bootconfig in the initrd.
 
 config INITRAMFS_PRESERVE_MTIME
 	bool "Preserve cpio archive mtimes in initramfs"

init/main.c

···
 early_param("loglevel", loglevel);
 
 #ifdef CONFIG_BLK_DEV_INITRD
-static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum)
+static void * __init get_boot_config_from_initrd(size_t *_size)
 {
 	u32 size, csum;
 	char *data;
···
 		return NULL;
 	}
 
+	if (xbc_calc_checksum(data, size) != csum) {
+		pr_err("bootconfig checksum failed\n");
+		return NULL;
+	}
+
 	/* Remove bootconfig from initramfs/initrd */
 	initrd_end = (unsigned long)data;
 	if (_size)
 		*_size = size;
-	if (_csum)
-		*_csum = csum;
 
 	return data;
 }
 #else
-static void * __init get_boot_config_from_initrd(u32 *_size, u32 *_csum)
+static void * __init get_boot_config_from_initrd(size_t *_size)
 {
 	return NULL;
 }
···
 static void __init setup_boot_config(void)
 {
 	static char tmp_cmdline[COMMAND_LINE_SIZE] __initdata;
-	const char *msg;
-	int pos;
-	u32 size, csum;
-	char *data, *err;
-	int ret;
+	const char *msg, *data;
+	int pos, ret;
+	size_t size;
+	char *err;
 
 	/* Cut out the bootconfig data even if we have no bootconfig option */
-	data = get_boot_config_from_initrd(&size, &csum);
+	data = get_boot_config_from_initrd(&size);
+	/* If there is no bootconfig in initrd, try embedded one. */
+	if (!data)
+		data = xbc_get_embedded_bootconfig(&size);
 
 	strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
 	err = parse_args("bootconfig", tmp_cmdline, NULL, 0, 0, 0, NULL,
···
 	}
 
 	if (size >= XBC_DATA_MAX) {
-		pr_err("bootconfig size %d greater than max size %d\n",
-			size, XBC_DATA_MAX);
-		return;
-	}
-
-	if (xbc_calc_checksum(data, size) != csum) {
-		pr_err("bootconfig checksum failed\n");
+		pr_err("bootconfig size %ld greater than max size %d\n",
+			(long)size, XBC_DATA_MAX);
 		return;
 	}
 
···
 				msg, pos);
 	} else {
 		xbc_get_info(&ret, NULL);
-		pr_info("Load bootconfig: %d bytes %d nodes\n", size, ret);
+		pr_info("Load bootconfig: %ld bytes %d nodes\n", (long)size, ret);
 		/* keys starting with "kernel." are passed via cmdline */
 		extra_command_line = xbc_make_cmdline("kernel");
 		/* Also, "init." keys are init arguments */
···
 static void __init setup_boot_config(void)
 {
 	/* Remove bootconfig data from initrd */
-	get_boot_config_from_initrd(NULL, NULL);
+	get_boot_config_from_initrd(NULL);
 }
 
 static int __init warn_bootconfig(char *str)

kernel/kprobes.c

···
 	preempt_enable();
 }
 
-#if !defined(CONFIG_KRETPROBE_ON_RETHOOK)
-static void free_rp_inst_rcu(struct rcu_head *head)
-{
-	struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu);
-
-	if (refcount_dec_and_test(&ri->rph->ref))
-		kfree(ri->rph);
-	kfree(ri);
-}
-NOKPROBE_SYMBOL(free_rp_inst_rcu);
-
-static void recycle_rp_inst(struct kretprobe_instance *ri)
-{
-	struct kretprobe *rp = get_kretprobe(ri);
-
-	if (likely(rp))
-		freelist_add(&ri->freelist, &rp->freelist);
-	else
-		call_rcu(&ri->rcu, free_rp_inst_rcu);
-}
-NOKPROBE_SYMBOL(recycle_rp_inst);
-
-/*
- * This function is called from delayed_put_task_struct() when a task is
- * dead and cleaned up to recycle any kretprobe instances associated with
- * this task. These left over instances represent probed functions that
- * have been called but will never return.
- */
-void kprobe_flush_task(struct task_struct *tk)
-{
-	struct kretprobe_instance *ri;
-	struct llist_node *node;
-
-	/* Early boot, not yet initialized. */
-	if (unlikely(!kprobes_initialized))
-		return;
-
-	kprobe_busy_begin();
-
-	node = __llist_del_all(&tk->kretprobe_instances);
-	while (node) {
-		ri = container_of(node, struct kretprobe_instance, llist);
-		node = node->next;
-
-		recycle_rp_inst(ri);
-	}
-
-	kprobe_busy_end();
-}
-NOKPROBE_SYMBOL(kprobe_flush_task);
-
-static inline void free_rp_inst(struct kretprobe *rp)
-{
-	struct kretprobe_instance *ri;
-	struct freelist_node *node;
-	int count = 0;
-
-	node = rp->freelist.head;
-	while (node) {
-		ri = container_of(node, struct kretprobe_instance, freelist);
-		node = node->next;
-
-		kfree(ri);
-		count++;
-	}
-
-	if (refcount_sub_and_test(count, &rp->rph->ref)) {
-		kfree(rp->rph);
-		rp->rph = NULL;
-	}
-}
-#endif	/* !CONFIG_KRETPROBE_ON_RETHOOK */
-
 /* Add the new probe to 'ap->list'. */
 static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
 {
···
 #ifdef CONFIG_KRETPROBES
 
 #if !defined(CONFIG_KRETPROBE_ON_RETHOOK)
+static void free_rp_inst_rcu(struct rcu_head *head)
+{
+	struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu);
+
+	if (refcount_dec_and_test(&ri->rph->ref))
+		kfree(ri->rph);
+	kfree(ri);
+}
+NOKPROBE_SYMBOL(free_rp_inst_rcu);
+
+static void recycle_rp_inst(struct kretprobe_instance *ri)
+{
+	struct kretprobe *rp = get_kretprobe(ri);
+
+	if (likely(rp))
+		freelist_add(&ri->freelist, &rp->freelist);
+	else
+		call_rcu(&ri->rcu, free_rp_inst_rcu);
+}
+NOKPROBE_SYMBOL(recycle_rp_inst);
+
+/*
+ * This function is called from delayed_put_task_struct() when a task is
+ * dead and cleaned up to recycle any kretprobe instances associated with
+ * this task. These left over instances represent probed functions that
+ * have been called but will never return.
+ */
+void kprobe_flush_task(struct task_struct *tk)
+{
+	struct kretprobe_instance *ri;
+	struct llist_node *node;
+
+	/* Early boot, not yet initialized. */
+	if (unlikely(!kprobes_initialized))
+		return;
+
+	kprobe_busy_begin();
+
+	node = __llist_del_all(&tk->kretprobe_instances);
+	while (node) {
+		ri = container_of(node, struct kretprobe_instance, llist);
+		node = node->next;
+
+		recycle_rp_inst(ri);
+	}
+
+	kprobe_busy_end();
+}
+NOKPROBE_SYMBOL(kprobe_flush_task);
+
+static inline void free_rp_inst(struct kretprobe *rp)
+{
+	struct kretprobe_instance *ri;
+	struct freelist_node *node;
+	int count = 0;
+
+	node = rp->freelist.head;
+	while (node) {
+		ri = container_of(node, struct kretprobe_instance, freelist);
+		node = node->next;
+
+		kfree(ri);
+		count++;
+	}
+
+	if (refcount_sub_and_test(count, &rp->rph->ref)) {
+		kfree(rp->rph);
+		rp->rph = NULL;
+	}
+}
+
 /* This assumes the 'tsk' is the current task or the is not running. */
 static kprobe_opcode_t *__kretprobe_find_ret_addr(struct task_struct *tsk,
 						  struct llist_node **cur)

kernel/trace/Makefile

···
 GCOV_PROFILE := y
 endif
 
+# Functions in this file could be invoked from early interrupt
+# code and produce random code coverage.
+KCOV_INSTRUMENT_trace_preemptirq.o := n
+
 CFLAGS_bpf_trace.o := -I$(src)
 
 CFLAGS_trace_benchmark.o := -I$(src)

kernel/trace/ftrace.c

···
 #include "trace_output.h"
 #include "trace_stat.h"
 
+#define FTRACE_INVALID_FUNCTION		"__ftrace_invalid_address__"
+
 #define FTRACE_WARN_ON(cond)			\
 	({					\
 		int ___r = cond;		\
···
 ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
 struct ftrace_ops global_ops;
 
-/* Defined by vmlinux.lds.h see the commment above arch_ftrace_ops_list_func for details */
+/* Defined by vmlinux.lds.h see the comment above arch_ftrace_ops_list_func for details */
 void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
 			  struct ftrace_ops *op, struct ftrace_regs *fregs);
 
···
 static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
 {
 	struct ftrace_profile_stat *stat;
-	struct dentry *entry;
 	char *name;
 	int ret;
 	int cpu;
···
 		}
 	}
 
-	entry = tracefs_create_file("function_profile_enabled",
-				    TRACE_MODE_WRITE, d_tracer, NULL,
-				    &ftrace_profile_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'function_profile_enabled' entry\n");
+	trace_create_file("function_profile_enabled",
+			  TRACE_MODE_WRITE, d_tracer, NULL,
+			  &ftrace_profile_fops);
 }
 
 #else /* CONFIG_FUNCTION_PROFILER */
···
  * archs can override this function if they must do something
  * before the modifying code is performed.
  */
-int __weak ftrace_arch_code_modify_prepare(void)
+void __weak ftrace_arch_code_modify_prepare(void)
 {
-	return 0;
 }
 
 /*
  * archs can override this function if they must do something
  * after the modifying code is performed.
  */
-int __weak ftrace_arch_code_modify_post_process(void)
+void __weak ftrace_arch_code_modify_post_process(void)
 {
-	return 0;
 }
 
 void ftrace_modify_all_code(int command)
···
 
 static void ftrace_run_update_code(int command)
 {
-	int ret;
-
-	ret = ftrace_arch_code_modify_prepare();
-	FTRACE_WARN_ON(ret);
-	if (ret)
-		return;
+	ftrace_arch_code_modify_prepare();
 
 	/*
 	 * By default we use stop_machine() to modify the code.
···
 	 */
 	arch_ftrace_update_code(command);
 
-	ret = ftrace_arch_code_modify_post_process();
-	FTRACE_WARN_ON(ret);
+	ftrace_arch_code_modify_post_process();
 }
 
 static void ftrace_run_modify_code(struct ftrace_ops *ops, int command,
···
 		seq_printf(m, " ->%pS", ptr);
 }
 
+#ifdef FTRACE_MCOUNT_MAX_OFFSET
+/*
+ * Weak functions can still have an mcount/fentry that is saved in
+ * the __mcount_loc section. These can be detected by having a
+ * symbol offset of greater than FTRACE_MCOUNT_MAX_OFFSET, as the
+ * symbol found by kallsyms is not the function that the mcount/fentry
+ * is part of. The offset is much greater in these cases.
+ *
+ * Test the record to make sure that the ip points to a valid kallsyms
+ * and if not, mark it disabled.
+ */
+static int test_for_valid_rec(struct dyn_ftrace *rec)
+{
+	char str[KSYM_SYMBOL_LEN];
+	unsigned long offset;
+	const char *ret;
+
+	ret = kallsyms_lookup(rec->ip, NULL, &offset, NULL, str);
+
+	/* Weak functions can cause invalid addresses */
+	if (!ret || offset > FTRACE_MCOUNT_MAX_OFFSET) {
+		rec->flags |= FTRACE_FL_DISABLED;
+		return 0;
+	}
+	return 1;
+}
+
+static struct workqueue_struct *ftrace_check_wq __initdata;
+static struct work_struct ftrace_check_work __initdata;
+
+/*
+ * Scan all the mcount/fentry entries to make sure they are valid.
+ */
+static __init void ftrace_check_work_func(struct work_struct *work)
+{
+	struct ftrace_page *pg;
+	struct dyn_ftrace *rec;
+
+	mutex_lock(&ftrace_lock);
+	do_for_each_ftrace_rec(pg, rec) {
+		test_for_valid_rec(rec);
+	} while_for_each_ftrace_rec();
+	mutex_unlock(&ftrace_lock);
+}
+
+static int __init ftrace_check_for_weak_functions(void)
+{
+	INIT_WORK(&ftrace_check_work, ftrace_check_work_func);
+
+	ftrace_check_wq = alloc_workqueue("ftrace_check_wq", WQ_UNBOUND, 0);
+
+	queue_work(ftrace_check_wq, &ftrace_check_work);
+	return 0;
+}
+
+static int __init ftrace_check_sync(void)
+{
+	/* Make sure the ftrace_check updates are finished */
+	if (ftrace_check_wq)
+		destroy_workqueue(ftrace_check_wq);
+	return 0;
+}
+
+late_initcall_sync(ftrace_check_sync);
+subsys_initcall(ftrace_check_for_weak_functions);
+
+static int print_rec(struct seq_file *m, unsigned long ip)
+{
+	unsigned long offset;
+	char str[KSYM_SYMBOL_LEN];
+	char *modname;
+	const char *ret;
+
+	ret = kallsyms_lookup(ip, NULL, &offset, &modname, str);
+	/* Weak functions can cause invalid addresses */
+	if (!ret || offset > FTRACE_MCOUNT_MAX_OFFSET) {
+		snprintf(str, KSYM_SYMBOL_LEN, "%s_%ld",
+			 FTRACE_INVALID_FUNCTION, offset);
+		ret = NULL;
+	}
+
+	seq_puts(m, str);
+	if (modname)
+		seq_printf(m, " [%s]", modname);
+	return ret == NULL ? -1 : 0;
+}
+#else
+static inline int test_for_valid_rec(struct dyn_ftrace *rec)
+{
+	return 1;
+}
+
+static inline int print_rec(struct seq_file *m, unsigned long ip)
+{
+	seq_printf(m, "%ps", (void *)ip);
+	return 0;
+}
+#endif
+
 static int t_show(struct seq_file *m, void *v)
 {
 	struct ftrace_iterator *iter = m->private;
···
 	if (!rec)
 		return 0;
 
-	seq_printf(m, "%ps", (void *)rec->ip);
+	if (print_rec(m, rec->ip)) {
+		/* This should only happen when a rec is disabled */
+		WARN_ON_ONCE(!(rec->flags & FTRACE_FL_DISABLED));
+		seq_putc(m, '\n');
+		return 0;
+	}
+
 	if (iter->flags & FTRACE_ITER_ENABLED) {
 		struct ftrace_ops *ops;
 
···
 	return 0;
 }
 
+#ifdef FTRACE_MCOUNT_MAX_OFFSET
+static int lookup_ip(unsigned long ip, char **modname, char *str)
+{
+	unsigned long offset;
+
+	kallsyms_lookup(ip, NULL, &offset, modname, str);
+	if (offset > FTRACE_MCOUNT_MAX_OFFSET)
+		return -1;
+	return 0;
+}
+#else
+static int lookup_ip(unsigned long ip, char **modname, char *str)
+{
+	kallsyms_lookup(ip, NULL, NULL, modname, str);
+	return 0;
+}
+#endif
+
 static int
 ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g,
 		struct ftrace_glob *mod_g, int exclude_mod)
···
 	char str[KSYM_SYMBOL_LEN];
 	char *modname;
 
-	kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
+	if (lookup_ip(rec->ip, &modname, str)) {
+		/* This should only happen when a rec is disabled */
+		WARN_ON_ONCE(system_state == SYSTEM_RUNNING &&
+			     !(rec->flags & FTRACE_FL_DISABLED));
+		return 0;
+	}
 
 	if (mod_g) {
 		int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0;
···
  * @ip: The instruction pointer address to remove the data from
  *
  * Returns the data if it is found, otherwise NULL.
- * Note, if the data pointer is used as the data itself, (see 
+ * Note, if the data pointer is used as the data itself, (see
  * ftrace_func_mapper_find_ip(), then the return value may be meaningless,
  * if the data pointer was set to zero.
  */
···
 			       struct ftrace_probe_ops *probe_ops,
 			       void *data)
 {
+	struct ftrace_func_probe *probe = NULL, *iter;
 	struct ftrace_func_entry *entry;
-	struct ftrace_func_probe *probe;
 	struct ftrace_hash **orig_hash;
 	struct ftrace_hash *old_hash;
 	struct ftrace_hash *hash;
···
 
 	mutex_lock(&ftrace_lock);
 	/* Check if the probe_ops is already registered */
-	list_for_each_entry(probe, &tr->func_probes, list) {
-		if (probe->probe_ops == probe_ops)
+	list_for_each_entry(iter, &tr->func_probes, list) {
+		if (iter->probe_ops == probe_ops) {
+			probe = iter;
 			break;
+		}
 	}
-	if (&probe->list == &tr->func_probes) {
+	if (!probe) {
 		probe = kzalloc(sizeof(*probe), GFP_KERNEL);
 		if (!probe) {
 			mutex_unlock(&ftrace_lock);
···
 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
 				      struct ftrace_probe_ops *probe_ops)
 {
+	struct ftrace_func_probe *probe = NULL, *iter;
 	struct ftrace_ops_hash old_hash_ops;
 	struct ftrace_func_entry *entry;
-	struct ftrace_func_probe *probe;
 	struct ftrace_glob func_g;
 	struct ftrace_hash **orig_hash;
 	struct ftrace_hash *old_hash;
···
 
 	mutex_lock(&ftrace_lock);
 	/* Check if the probe_ops is already registered */
-	list_for_each_entry(probe, &tr->func_probes, list) {
-		if (probe->probe_ops == probe_ops)
+	list_for_each_entry(iter, &tr->func_probes, list) {
+		if (iter->probe_ops == probe_ops) {
+			probe = iter;
 			break;
+		}
 	}
-	if (&probe->list == &tr->func_probes)
+	if (!probe)
 		goto err_unlock_ftrace;
 
 	ret = -EINVAL;
···
 		goto out_unlock;
 
 	ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0);
-	if (ret)
-		remove_hash_entry(direct_functions, entry);
 
 	if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) {
 		ret = register_ftrace_function(&direct_ops);
···
 	}
 
 	if (ret) {
+		remove_hash_entry(direct_functions, entry);
 		kfree(entry);
 		if (!direct->count) {
 			list_del_rcu(&direct->next);
···
 		    !within_module_init(rec->ip, mod))
 			break;
 
+		/* Weak functions should still be ignored */
+		if (!test_for_valid_rec(rec)) {
+			/* Clear all other flags. Should not be enabled anyway */
+			rec->flags = FTRACE_FL_DISABLED;
+			continue;
+		}
+
 		cnt = 0;
 
 		/*
···
 
 void ftrace_module_init(struct module *mod)
 {
+	int ret;
+
 	if (ftrace_disabled || !mod->num_ftrace_callsites)
 		return;
 
-	ftrace_process_locs(mod, mod->ftrace_callsites,
-			    mod->ftrace_callsites + mod->num_ftrace_callsites);
+	ret = ftrace_process_locs(mod, mod->ftrace_callsites,
+				  mod->ftrace_callsites + mod->num_ftrace_callsites);
+	if (ret)
+		pr_warn("ftrace: failed to allocate entries for module '%s' functions\n",
+			mod->name);
 }
 
 static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map,
···
 	pr_info("ftrace: allocating %ld entries in %ld pages\n",
 		count, count / ENTRIES_PER_PAGE + 1);
 
-	last_ftrace_enabled = ftrace_enabled = 1;
-
 	ret = ftrace_process_locs(NULL,
 				  __start_mcount_loc,
 				  __stop_mcount_loc);
+	if (ret) {
+		pr_warn("ftrace: failed to allocate entries for functions\n");
+		goto failed;
+	}
 
 	pr_info("ftrace: allocated %ld pages with %ld groups\n",
 		ftrace_number_of_pages, ftrace_number_of_groups);
+
+	last_ftrace_enabled = ftrace_enabled = 1;
 
 	set_ftrace_early_filters();
 

kernel/trace/pid_list.c

···
 /**
  * trace_pid_list_is_set - test if the pid is set in the list
  * @pid_list: The pid list to test
- * @pid: The pid to to see if set in the list.
+ * @pid: The pid to see if set in the list.
  *
- * Tests if @pid is is set in the @pid_list. This is usually called
+ * Tests if @pid is set in the @pid_list. This is usually called
  * from the scheduler when a task is scheduled. Its pid is checked
  * if it should be traced or not.
  *

kernel/trace/ring_buffer.c

···
 
 #include <asm/local.h>
 
+/*
+ * The "absolute" timestamp in the buffer is only 59 bits.
+ * If a clock has the 5 MSBs set, it needs to be saved and
+ * reinserted.
+ */
+#define TS_MSB		(0xf8ULL << 56)
+#define ABS_TS_MASK	(~TS_MSB)
+
 static void update_pages_handler(struct work_struct *work);
 
 /*
···
 	local_t		cnt;
 	local_t		top;
 	local_t		bottom;
+	local_t		msb;
 };
 #else
 #include <asm/local64.h>
···
  * For the ring buffer, 64 bit required operations for the time is
  * the following:
  *
- *  - Only need 59 bits (uses 60 to make it even).
  *  - Reads may fail if it interrupted a modification of the time stamp.
  *      It will succeed if it did not interrupt another write even if
  *      the read itself is interrupted by a write.
···
  */
 #define RB_TIME_SHIFT	30
 #define RB_TIME_VAL_MASK ((1 << RB_TIME_SHIFT) - 1)
+#define RB_TIME_MSB_SHIFT	 60
 
 static inline int rb_time_cnt(unsigned long val)
 {
···
 
 static inline bool __rb_time_read(rb_time_t *t, u64 *ret, unsigned long *cnt)
 {
-	unsigned long top, bottom;
+	unsigned long top, bottom, msb;
 	unsigned long c;
 
 	/*
···
 		c = local_read(&t->cnt);
 		top = local_read(&t->top);
 		bottom = local_read(&t->bottom);
+		msb = local_read(&t->msb);
 	} while (c != local_read(&t->cnt));
 
 	*cnt = rb_time_cnt(top);
···
 	if (*cnt != rb_time_cnt(bottom))
 		return false;
 
-	*ret = rb_time_val(top, bottom);
+	/* The shift to msb will lose its cnt bits */
+	*ret = rb_time_val(top, bottom) | ((u64)msb << RB_TIME_MSB_SHIFT);
 	return true;
 }
 
···
 	return (val & RB_TIME_VAL_MASK) | ((cnt & 3) << RB_TIME_SHIFT);
 }
 
-static inline void rb_time_split(u64 val, unsigned long *top, unsigned long *bottom)
+static inline void rb_time_split(u64 val, unsigned long *top, unsigned long *bottom,
+				 unsigned long *msb)
 {
 	*top = (unsigned long)((val >> RB_TIME_SHIFT) & RB_TIME_VAL_MASK);
 	*bottom = (unsigned long)(val & RB_TIME_VAL_MASK);
+	*msb = (unsigned long)(val >> RB_TIME_MSB_SHIFT);
 }
 
 static inline void rb_time_val_set(local_t *t, unsigned long val, unsigned long cnt)
···
 
 static void rb_time_set(rb_time_t *t, u64 val)
 {
-	unsigned long cnt, top, bottom;
+	unsigned long cnt, top, bottom, msb;
 
-	rb_time_split(val, &top, &bottom);
+	rb_time_split(val, &top, &bottom, &msb);
 
 	/* Writes always succeed with a valid number even if it gets interrupted. */
 	do {
 		cnt = local_inc_return(&t->cnt);
 		rb_time_val_set(&t->top, top, cnt);
 		rb_time_val_set(&t->bottom, bottom, cnt);
+		rb_time_val_set(&t->msb, val >> RB_TIME_MSB_SHIFT, cnt);
 	} while (cnt != local_read(&t->cnt));
 }
 
···
 
 static int rb_time_cmpxchg(rb_time_t *t, u64 expect, u64 set)
 {
-	unsigned long cnt, top, bottom;
-	unsigned long cnt2, top2, bottom2;
+	unsigned long cnt, top, bottom, msb;
+	unsigned long cnt2, top2, bottom2, msb2;
 	u64 val;
 
 	/* The cmpxchg always fails if it interrupted an update */
···
 
 	 cnt2 = cnt + 1;
 
-	 rb_time_split(val, &top, &bottom);
+	 rb_time_split(val, &top, &bottom, &msb);
 	 top = rb_time_val_cnt(top, cnt);
 	 bottom = rb_time_val_cnt(bottom, cnt);
 
-	 rb_time_split(set, &top2, &bottom2);
+	 rb_time_split(set, &top2, &bottom2, &msb2);
 	 top2 = rb_time_val_cnt(top2, cnt2);
 	 bottom2 = rb_time_val_cnt(bottom2, cnt2);
 
 	if (!rb_time_read_cmpxchg(&t->cnt, cnt, cnt2))
+		return false;
+	if (!rb_time_read_cmpxchg(&t->msb, msb, msb2))
 		return false;
 	if (!rb_time_read_cmpxchg(&t->top, top, top2))
 		return false;
···
 }
 #endif
 
+/*
+ * The absolute time stamp drops the 5 MSBs and some clocks may
+ * require them. The rb_fix_abs_ts() will take a previous full
+ * time stamp, and add the 5 MSB of that time stamp on to the
+ * saved absolute time stamp. Then they are compared in case of
+ * the unlikely event that the latest time stamp incremented
+ * the 5 MSB.
+ */
+static inline u64 rb_fix_abs_ts(u64 abs, u64 save_ts)
+{
+	if (save_ts & TS_MSB) {
+		abs |= save_ts & TS_MSB;
+		/* Check for overflow */
+		if (unlikely(abs < save_ts))
+			abs += 1ULL << 59;
+	}
+	return abs;
+}
 
 static inline u64 rb_time_stamp(struct trace_buffer *buffer);
 
···
 	u64 ts;
 
 	/* If the event includes an absolute time, then just use that */
-	if (event->type_len == RINGBUF_TYPE_TIME_STAMP)
-		return rb_event_time_stamp(event);
+	if (event->type_len == RINGBUF_TYPE_TIME_STAMP) {
+		ts = rb_event_time_stamp(event);
+		return rb_fix_abs_ts(ts, cpu_buffer->tail_page->page->time_stamp);
+	}
 
 	nest = local_read(&cpu_buffer->committing);
 	verify_event(cpu_buffer, event);
···
 		(RB_ADD_STAMP_FORCE | RB_ADD_STAMP_ABSOLUTE);
 
 	if (unlikely(info->delta > (1ULL << 59))) {
+		/*
+		 * Some timers can use more than 59 bits, and when a timestamp
+		 * is added to the buffer, it will lose those bits.
+		 */
+		if (abs && (info->ts & TS_MSB)) {
+			info->delta &= ABS_TS_MASK;
+
 		/* did the clock go backwards */
-		if (info->before == info->after && info->before > info->ts) {
+		} else if (info->before == info->after && info->before > info->ts) {
 			/* not interrupted */
 			static int once;
 
···
 
 		case RINGBUF_TYPE_TIME_STAMP:
 			delta = rb_event_time_stamp(event);
-			ts = delta;
+			ts = rb_fix_abs_ts(delta, ts);
 			pr_warn("  [%lld] absolute:%lld TIME STAMP\n", ts, delta);
 			break;
 
···
 
 		case RINGBUF_TYPE_TIME_STAMP:
 			delta = rb_event_time_stamp(event);
-			ts = delta;
+			ts = rb_fix_abs_ts(delta, ts);
 			break;
 
 		case RINGBUF_TYPE_PADDING:
···
 
 	case RINGBUF_TYPE_TIME_STAMP:
 		delta = rb_event_time_stamp(event);
+		delta = rb_fix_abs_ts(delta, cpu_buffer->read_stamp);
 		cpu_buffer->read_stamp = delta;
 		return;
 
···
 
 	case RINGBUF_TYPE_TIME_STAMP:
 		delta = rb_event_time_stamp(event);
+		delta = rb_fix_abs_ts(delta, iter->read_stamp);
 		iter->read_stamp = delta;
 		return;
 
···
 	case RINGBUF_TYPE_TIME_STAMP:
 		if (ts) {
 			*ts = rb_event_time_stamp(event);
+			*ts = rb_fix_abs_ts(*ts, reader->page->time_stamp);
 			ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
 							 cpu_buffer->cpu, ts);
 		}
···
 	case RINGBUF_TYPE_TIME_STAMP:
 		if (ts) {
 			*ts = rb_event_time_stamp(event);
+			*ts = rb_fix_abs_ts(*ts, iter->head_page->page->time_stamp);
 			ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
 							 cpu_buffer->cpu, ts);
 		}
···
 		pr_info("        total events:   %ld\n", total_lost + total_read);
 		pr_info("  recorded len bytes:   %ld\n", total_len);
 		pr_info(" recorded size bytes:   %ld\n", total_size);
-		if (total_lost)
+		if (total_lost) {
 			pr_info(" With dropped events, record len and size may not match\n"
 				" alloced and written from above\n");
-		if (!total_lost) {
+		} else {
 			if (RB_WARN_ON(buffer, total_len != total_alloc ||
 				       total_size != total_written))
 				break;

kernel/trace/trace.c

···
 		pos = 0;
 
 		ret = trace_get_user(&parser, ubuf, cnt, &pos);
-		if (ret < 0 || !trace_parser_loaded(&parser))
+		if (ret < 0)
 			break;
 
 		read += ret;
 		ubuf += ret;
 		cnt -= ret;
+
+		if (!trace_parser_loaded(&parser))
+			break;
 
 		ret = -EINVAL;
 		if (kstrtoul(parser.buffer, 0, &val))
···
 	if (!nr_pids) {
 		/* Cleared the list of pids */
 		trace_pid_list_free(pid_list);
-		read = ret;
 		pid_list = NULL;
 	}
 
···
 EXPORT_SYMBOL_GPL(tracing_snapshot_cond);
 
 /**
- * tracing_snapshot_cond_data - get the user data associated with a snapshot
+ * tracing_cond_snapshot_data - get the user data associated with a snapshot
  * @tr:		The tracing instance
  *
  * When the user enables a conditional snapshot using
···
 	{ ktime_get_mono_fast_ns,	"mono",		1 },
 	{ ktime_get_raw_fast_ns,	"mono_raw",	1 },
 	{ ktime_get_boot_fast_ns,	"boot",		1 },
+	{ ktime_get_tai_fast_ns,	"tai",		1 },
 	ARCH_TRACE_CLOCKS
 };
 
···
 }
 EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve);
 
-static DEFINE_SPINLOCK(tracepoint_iter_lock);
+static DEFINE_RAW_SPINLOCK(tracepoint_iter_lock);
 static DEFINE_MUTEX(tracepoint_printk_mutex);
 
 static void output_printk(struct trace_event_buffer *fbuffer)
···
 
 	event = &fbuffer->trace_file->event_call->event;
 
-	spin_lock_irqsave(&tracepoint_iter_lock, flags);
+	raw_spin_lock_irqsave(&tracepoint_iter_lock, flags);
 	trace_seq_init(&iter->seq);
 	iter->ent = fbuffer->entry;
 	event_call->event.funcs->trace(iter, 0, event);
 	trace_seq_putc(&iter->seq, 0);
 	printk("%s", iter->seq.buffer);
 
-	spin_unlock_irqrestore(&tracepoint_iter_lock, flags);
+	raw_spin_unlock_irqrestore(&tracepoint_iter_lock, flags);
 }
 
 int tracepoint_printk_sysctl(struct ctl_table *table, int write,
···
 				       unsigned int flags)
 {
 	bool tgid = flags & TRACE_ITER_RECORD_TGID;
-	const char *space = "            ";
+	static const char space[] = "            ";
 	int prec = tgid ? 12 : 2;
 
 	print_event_info(buf, m);
···
 	struct tracer *type = iter->trace;
 	unsigned long entries;
 	unsigned long total;
-	const char *name = "preemption";
-
-	name = type->name;
+	const char *name = type->name;
 
 	get_total_entries(buf, &total, &entries);
 
···
 	"  error_log\t- error log for failed commands (that support it)\n"
 	"  buffer_size_kb\t- view and modify size of per cpu buffer\n"
 	"  buffer_total_size_kb  - view total size of all cpu buffers\n\n"
-	"  trace_clock\t\t-change the clock used to order events\n"
+	"  trace_clock\t\t- change the clock used to order events\n"
 	"       local:   Per cpu clock but may not be synced across CPUs\n"
 	"      global:   Synced across CPUs but slows tracing down.\n"
 	"     counter:   Not a clock, but just an increment\n"
···
 #ifdef CONFIG_X86_64
 	"     x86-tsc:   TSC cycle counter\n"
 #endif
-	"\n  timestamp_mode\t-view the mode used to timestamp events\n"
+	"\n  timestamp_mode\t- view the mode used to timestamp events\n"
 	"       delta:   Delta difference against a buffer-wide timestamp\n"
 	"    absolute:   Absolute (standalone) timestamp\n"
 	"\n  trace_marker\t\t- Writes into this file writes into the kernel buffer\n"
···
 	tr->current_trace = &nop_trace;
 }
 
+static bool tracer_options_updated;
+
 static void add_tracer_options(struct trace_array *tr, struct tracer *t)
 {
 	/* Only enable if the directory has been created already. */
 	if (!tr->dir)
+		return;
+
+	/* Only create trace option files after update_tracer_options finish */
+	if (!tracer_options_updated)
 		return;
 
 	create_trace_option_files(tr, t);
···
 {
 	struct trace_array *tr = filp->private_data;
 	char buf[MAX_TRACER_SIZE+1];
-	int i;
+	char *name;
 	size_t ret;
 	int err;
 
···
 
 	buf[cnt] = 0;
 
-	/* strip ending whitespace. */
-	for (i = cnt - 1; i > 0 && isspace(buf[i]); i--)
-		buf[i] = 0;
+	name = strim(buf);
 
-	err = tracing_set_tracer(tr, buf);
+	err = tracing_set_tracer(tr, name);
 	if (err)
 		return err;
 
···
 static void update_tracer_options(struct trace_array *tr)
 {
 	mutex_lock(&trace_types_lock);
+	tracer_options_updated = true;
 	__update_tracer_options(tr);
 	mutex_unlock(&trace_types_lock);
 }
···
 
 static struct workqueue_struct *eval_map_wq __initdata;
 static struct work_struct eval_map_work __initdata;
+static struct work_struct tracerfs_init_work __initdata;
 
 static void __init eval_map_work_func(struct work_struct *work)
 {
···
 	queue_work(eval_map_wq, &eval_map_work);
 	return 0;
 }
+
+subsys_initcall(trace_eval_init);
 
 static int __init trace_eval_sync(void)
 {
···
 };
 #endif /* CONFIG_MODULES */
 
-static __init int tracer_init_tracefs(void)
+static __init void tracer_init_tracefs_work_func(struct work_struct *work)
 {
-	int ret;
-
-	trace_access_lock_init();
-
-	ret = tracing_init_dentry();
-	if (ret)
-		return 0;
 
 	event_trace_init();
 
···
 	trace_create_file("saved_tgids", TRACE_MODE_READ, NULL,
 			NULL, &tracing_saved_tgids_fops);
 
-	trace_eval_init();
-
 	trace_create_eval_file(NULL);
 
 #ifdef CONFIG_MODULES
···
 	create_trace_instances(NULL);
 
 	update_tracer_options(&global_trace);
+}
+
+static __init int tracer_init_tracefs(void)
+{
+	int ret;
+
+	trace_access_lock_init();
+
+	ret = tracing_init_dentry();
+	if (ret)
+		return 0;
+
+	if (eval_map_wq) {
+		INIT_WORK(&tracerfs_init_work, tracer_init_tracefs_work_func);
+		queue_work(eval_map_wq, &tracerfs_init_work);
+	} else {
+		tracer_init_tracefs_work_func(NULL);
+	}
 
 	return 0;
 }

kernel/trace/trace.h

···
 };
 
 extern int event_enable_trigger_print(struct seq_file *m,
-				      struct event_trigger_ops *ops,
 				      struct event_trigger_data *data);
-extern void event_enable_trigger_free(struct event_trigger_ops *ops,
-				      struct event_trigger_data *data);
+extern void event_enable_trigger_free(struct event_trigger_data *data);
 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
 				      struct trace_event_file *file,
-				      char *glob, char *cmd, char *param);
+				      char *glob, char *cmd,
+				      char *param_and_filter);
 extern int event_enable_register_trigger(char *glob,
 					 struct event_trigger_data *data,
 					 struct trace_event_file *file);
···
 					    struct event_trigger_data *test,
 					    struct trace_event_file *file);
 extern void trigger_data_free(struct event_trigger_data *data);
-extern int event_trigger_init(struct event_trigger_ops *ops,
-			      struct event_trigger_data *data);
+extern int event_trigger_init(struct event_trigger_data *data);
 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 int event_trigger_register(struct event_command *cmd_ops,
 				  struct trace_event_file *file,
 				  char *glob,
-				  char *cmd,
-				  char *trigger,
-				  struct event_trigger_data *trigger_data,
-				  int *n_registered);
+				  struct event_trigger_data *trigger_data);
+extern void event_trigger_unregister(struct event_command *cmd_ops,
+				     struct trace_event_file *file,
+				     char *glob,
+				     struct event_trigger_data *trigger_data);
 
 /**
  * struct event_trigger_ops - callbacks for trace event triggers
···
 					   struct trace_buffer *buffer,
 					   void *rec,
 					   struct ring_buffer_event *rbe);
-	int			(*init)(struct event_trigger_ops *ops,
-					struct event_trigger_data *data);
-	void			(*free)(struct event_trigger_ops *ops,
-					struct event_trigger_data *data);
+	int			(*init)(struct event_trigger_data *data);
+	void			(*free)(struct event_trigger_data *data);
 	int			(*print)(struct seq_file *m,
-					 struct event_trigger_ops *ops,
 					 struct event_trigger_data *data);
 };
 

kernel/trace/trace_boot.c

···
 {
 	struct xbc_node *node;
 	const char *p, *handler;
-	int ret;
+	int ret = 0;
 
 	handler = xbc_node_get_data(hnode);
 

kernel/trace/trace_dynevent.c

···
 /* Make a tracefs interface for controlling dynamic events */
 static __init int init_dynamic_event(void)
 {
-	struct dentry *entry;
 	int ret;
 
 	ret = tracing_init_dentry();
 	if (ret)
 		return 0;
 
-	entry = tracefs_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
-				    NULL, &dynamic_events_ops);
-
-	/* Event list interface */
-	if (!entry)
-		pr_warn("Could not create tracefs 'dynamic_events' entry\n");
+	trace_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
+			  NULL, &dynamic_events_ops);
 
 	return 0;
 }

kernel/trace/trace_eprobe.c

···
  * functions are just stubs to fulfill what is needed to use the trigger
  * infrastructure.
  */
-static int eprobe_trigger_init(struct event_trigger_ops *ops,
-			       struct event_trigger_data *data)
+static int eprobe_trigger_init(struct event_trigger_data *data)
 {
 	return 0;
 }
 
-static void eprobe_trigger_free(struct event_trigger_ops *ops,
-				struct event_trigger_data *data)
+static void eprobe_trigger_free(struct event_trigger_data *data)
 {
 
 }
 
 static int eprobe_trigger_print(struct seq_file *m,
-				struct event_trigger_ops *ops,
 				struct event_trigger_data *data)
 {
 	/* Do not print eprobe event triggers */
···
 
 static int eprobe_trigger_cmd_parse(struct event_command *cmd_ops,
 				    struct trace_event_file *file,
-				    char *glob, char *cmd, char *param)
+				    char *glob, char *cmd,
+				    char *param_and_filter)
 {
 	return -1;
 }
···
 static int disable_eprobe(struct trace_eprobe *ep,
 			  struct trace_array *tr)
 {
-	struct event_trigger_data *trigger;
+	struct event_trigger_data *trigger = NULL, *iter;
 	struct trace_event_file *file;
 	struct eprobe_data *edata;
 
···
 	if (!file)
 		return -ENOENT;
 
-	list_for_each_entry(trigger, &file->triggers, list) {
-		if (!(trigger->flags & EVENT_TRIGGER_FL_PROBE))
+	list_for_each_entry(iter, &file->triggers, list) {
+		if (!(iter->flags & EVENT_TRIGGER_FL_PROBE))
 			continue;
-		edata = trigger->private_data;
-		if (edata->ep == ep)
+		edata = iter->private_data;
+		if (edata->ep == ep) {
+			trigger = iter;
 			break;
+		}
 	}
-	if (list_entry_is_head(trigger, &file->triggers, list))
+	if (!trigger)
 		return -ENODEV;
 
 	list_del_rcu(&trigger->list);

kernel/trace/trace_events.c

···
 			if (!(dereference_flags & (1ULL << arg)))
 				goto next_arg;
 
-			/* Check for __get_sockaddr */;
-			if (str_has_prefix(fmt + i, "__get_sockaddr(")) {
-				dereference_flags &= ~(1ULL << arg);
-				goto next_arg;
-			}
-
 			/* Find the REC-> in the argument */
 			c = strchr(fmt + i, ',');
 			r = strstr(fmt + i, "REC->");
···
 				a = strchr(fmt + i, '&');
 				if ((a && (a < r)) || test_field(r, call))
 					dereference_flags &= ~(1ULL << arg);
+			} else if ((r = strstr(fmt + i, "__get_dynamic_array(")) &&
+				   (!c || r < c)) {
+				dereference_flags &= ~(1ULL << arg);
+			} else if ((r = strstr(fmt + i, "__get_sockaddr(")) &&
+				   (!c || r < c)) {
+				dereference_flags &= ~(1ULL << arg);
 			}
+
 		next_arg:
 			i--;
 			arg++;
···
 
 static int subsystem_open(struct inode *inode, struct file *filp)
 {
+	struct trace_subsystem_dir *dir = NULL, *iter_dir;
+	struct trace_array *tr = NULL, *iter_tr;
 	struct event_subsystem *system = NULL;
-	struct trace_subsystem_dir *dir = NULL; /* Initialize for gcc */
-	struct trace_array *tr;
 	int ret;
 
 	if (tracing_is_disabled())
···
 	/* Make sure the system still exists */
 	mutex_lock(&event_mutex);
 	mutex_lock(&trace_types_lock);
-	list_for_each_entry(tr, &ftrace_trace_arrays, list) {
-		list_for_each_entry(dir, &tr->systems, list) {
-			if (dir == inode->i_private) {
+	list_for_each_entry(iter_tr, &ftrace_trace_arrays, list) {
+		list_for_each_entry(iter_dir, &iter_tr->systems, list) {
+			if (iter_dir == inode->i_private) {
 				/* Don't open systems with no events */
+				tr = iter_tr;
+				dir = iter_dir;
 				if (dir->nr_events) {
 					__get_system_dir(dir);
 					system = dir->subsystem;
···
 
 	if (!system)
 		return -ENODEV;
-
-	/* Some versions of gcc think dir can be uninitialized here */
-	WARN_ON(!dir);
 
 	/* Still need to increment the ref count of the system */
 	if (trace_array_get(tr) < 0) {
···
 event_subsystem_dir(struct trace_array *tr, const char *name,
 		    struct trace_event_file *file, struct dentry *parent)
 {
+	struct event_subsystem *system, *iter;
 	struct trace_subsystem_dir *dir;
-	struct event_subsystem *system;
 	struct dentry *entry;
 
 	/* First see if we did not already create this dir */
···
 	}
 
 	/* Now see if the system itself exists. */
-	list_for_each_entry(system, &event_subsystems, list) {
-		if (strcmp(system->name, name) == 0)
+	system = NULL;
+	list_for_each_entry(iter, &event_subsystems, list) {
+		if (strcmp(iter->name, name) == 0) {
+			system = iter;
 			break;
+		}
 	}
-	/* Reset system variable when not found */
-	if (&system->list == &event_subsystems)
-		system = NULL;
 
 	dir = kmalloc(sizeof(*dir), GFP_KERNEL);
 	if (!dir)
···
 	struct dentry *d_events;
 	struct dentry *entry;
 
-	entry = tracefs_create_file("set_event", TRACE_MODE_WRITE, parent,
-				    tr, &ftrace_set_event_fops);
-	if (!entry) {
-		pr_warn("Could not create tracefs 'set_event' entry\n");
+	entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent,
+				  tr, &ftrace_set_event_fops);
+	if (!entry)
 		return -ENOMEM;
-	}
 
 	d_events = tracefs_create_dir("events", parent);
 	if (!d_events) {
···
 
 	/* There are not as crucial, just warn if they are not created */
 
-	entry = tracefs_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
-				    tr, &ftrace_set_event_pid_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'set_event_pid' entry\n");
+	trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
+			  tr, &ftrace_set_event_pid_fops);
 
-	entry = tracefs_create_file("set_event_notrace_pid",
-				    TRACE_MODE_WRITE, parent, tr,
-				    &ftrace_set_event_notrace_pid_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n");
+	trace_create_file("set_event_notrace_pid",
+			  TRACE_MODE_WRITE, parent, tr,
+			  &ftrace_set_event_notrace_pid_fops);
 
 	/* ring buffer internal formats */
 	trace_create_file("header_page", TRACE_MODE_READ, d_events,
···
 __init int event_trace_init(void)
 {
 	struct trace_array *tr;
-	struct dentry *entry;
 	int ret;
 
 	tr = top_trace_array();
 	if (!tr)
 		return -ENODEV;
 
-	entry = tracefs_create_file("available_events", TRACE_MODE_READ,
-				    NULL, tr, &ftrace_avail_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'available_events' entry\n");
+	trace_create_file("available_events", TRACE_MODE_READ,
+			  NULL, tr, &ftrace_avail_fops);
 
 	ret = early_event_add_tracer(NULL, tr);
 	if (ret)

kernel/trace/trace_events_filter.c

···
  * create_filter - create a filter for a trace_event_call
  * @tr: the trace array associated with these events
  * @call: trace_event_call to create a filter for
- * @filter_str: filter string
+ * @filter_string: filter string
  * @set_str: remember @filter_str and enable detailed error in filter
  * @filterp: out param for created filter (always updated on return)
  *           Must be a pointer that references a NULL pointer.

kernel/trace/trace_events_hist.c

···
 	return err;
  free:
 	kfree(ref_field->system);
+	ref_field->system = NULL;
 	kfree(ref_field->event_name);
+	ref_field->event_name = NULL;
 	kfree(ref_field->name);
+	ref_field->name = NULL;
 
 	goto out;
 }
···
 static struct event_command trigger_hist_cmd;
 static int event_hist_trigger_parse(struct event_command *cmd_ops,
 				    struct trace_event_file *file,
-				    char *glob, char *cmd, char *param);
+				    char *glob, char *cmd,
+				    char *param_and_filter);
 
 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
 			    struct hist_trigger_data *hist_data,
···
 	return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
 }
 
-static const char *no_comm = "(no comm)";
+static const char no_comm[] = "(no comm)";
 
 static u64 hist_field_execname(struct hist_field *hist_field,
 			       struct tracing_map_elt *elt,
···
 		seq_puts(m, "\n\n");
 
 	seq_puts(m, "# event histogram\n#\n# trigger info: ");
-	data->ops->print(m, data->ops, data);
+	data->ops->print(m, data);
 	seq_puts(m, "#\n\n");
 
 	hist_data = data->private_data;
···
 		seq_puts(m, "\n\n");
 
 	seq_puts(m, "# event histogram\n#\n# trigger info: ");
-	data->ops->print(m, data->ops, data);
+	data->ops->print(m, data);
 	seq_puts(m, "#\n\n");
 
 	hist_data = data->private_data;
···
 }
 
 static int event_hist_trigger_print(struct seq_file *m,
-				    struct event_trigger_ops *ops,
 				    struct event_trigger_data *data)
 {
 	struct hist_trigger_data *hist_data = data->private_data;
···
 	return 0;
 }
 
-static int event_hist_trigger_init(struct event_trigger_ops *ops,
-				   struct event_trigger_data *data)
+static int event_hist_trigger_init(struct event_trigger_data *data)
 {
 	struct hist_trigger_data *hist_data = data->private_data;
 
···
 	}
 }
 
-static void event_hist_trigger_free(struct event_trigger_ops *ops,
-				    struct event_trigger_data *data)
+static void event_hist_trigger_free(struct event_trigger_data *data)
 {
 	struct hist_trigger_data *hist_data = data->private_data;
 
···
 	.free			= event_hist_trigger_free,
 };
 
-static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
-					 struct event_trigger_data *data)
+static int event_hist_trigger_named_init(struct event_trigger_data *data)
 {
 	data->ref++;
 
 	save_named_trigger(data->named_data->name, data);
 
-	event_hist_trigger_init(ops, data->named_data);
+	event_hist_trigger_init(data->named_data);
 
 	return 0;
 }
 
-static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
-					  struct event_trigger_data *data)
+static void event_hist_trigger_named_free(struct event_trigger_data *data)
 {
 	if (WARN_ON_ONCE(data->ref <= 0))
 		return;
 
-	event_hist_trigger_free(ops, data->named_data);
+	event_hist_trigger_free(data->named_data);
 
 	data->ref--;
 	if (!data->ref) {
···
 	return true;
 }
 
+static bool existing_hist_update_only(char *glob,
+				      struct event_trigger_data *data,
+				      struct trace_event_file *file)
+{
+	struct hist_trigger_data *hist_data = data->private_data;
+	struct event_trigger_data *test, *named_data = NULL;
+	bool updated = false;
+
+	if (!hist_data->attrs->pause && !hist_data->attrs->cont &&
+	    !hist_data->attrs->clear)
+		goto out;
+
+	if (hist_data->attrs->name) {
+		named_data = find_named_trigger(hist_data->attrs->name);
+		if (named_data) {
+			if (!hist_trigger_match(data, named_data, named_data,
+						true))
+				goto out;
+		}
+	}
+
+	if (hist_data->attrs->name && !named_data)
+		goto out;
+
+	list_for_each_entry(test, &file->triggers, list) {
+		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+			if (!hist_trigger_match(data, test, named_data, false))
+				continue;
+			if (hist_data->attrs->pause)
+				test->paused = true;
+			else if (hist_data->attrs->cont)
+				test->paused = false;
+			else if (hist_data->attrs->clear)
+				hist_clear(test);
+			updated = true;
+			goto out;
+		}
+	}
+ out:
+	return updated;
+}
+
 static int hist_register_trigger(char *glob,
 				 struct event_trigger_data *data,
 				 struct trace_event_file *file)
···
 
 	list_for_each_entry(test, &file->triggers, list) {
 		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
-			if (!hist_trigger_match(data, test, named_data, false))
-				continue;
-			if (hist_data->attrs->pause)
-				test->paused = true;
-			else if (hist_data->attrs->cont)
-				test->paused = false;
-			else if (hist_data->attrs->clear)
-				hist_clear(test);
-			else {
+			if (hist_trigger_match(data, test, named_data, false)) {
 				hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0);
 				ret = -EEXIST;
+				goto out;
 			}
-			goto out;
 		}
 	}
  new:
···
 	}
 
 	if (data->ops->init) {
-		ret = data->ops->init(data->ops, data);
+		ret = data->ops->init(data);
 		if (ret < 0)
 			goto out;
 	}
···
 
 	if (named_data)
 		destroy_hist_data(hist_data);
-
-	ret++;
  out:
 	return ret;
 }
···
 				    struct event_trigger_data *data,
 				    struct trace_event_file *file)
 {
+	struct event_trigger_data *test = NULL, *iter, *named_data = NULL;
 	struct hist_trigger_data *hist_data = data->private_data;
-	struct event_trigger_data *test, *named_data = NULL;
-	bool unregistered = false;
 
 	lockdep_assert_held(&event_mutex);
 
 	if (hist_data->attrs->name)
 		named_data = find_named_trigger(hist_data->attrs->name);
 
-	list_for_each_entry(test, &file->triggers, list) {
-		if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
-			if (!hist_trigger_match(data, test, named_data, false))
+	list_for_each_entry(iter, &file->triggers, list) {
+		if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) {
+			if (!hist_trigger_match(data, iter, named_data, false))
 				continue;
-			unregistered = true;
+			test = iter;
 			list_del_rcu(&test->list);
 			trace_event_trigger_enable_disable(file, 0);
 			update_cond_flag(file);
···
 		}
 	}
 
-	if (unregistered && test->ops->free)
-		test->ops->free(test->ops, test);
+	if (test && test->ops->free)
+		test->ops->free(test);
 
 	if (hist_data->enable_timestamps) {
-		if (!hist_data->remove || unregistered)
+		if (!hist_data->remove || test)
 			tracing_set_filter_buffering(file->tr, false);
 	}
 }
···
 			if (hist_data->enable_timestamps)
 				tracing_set_filter_buffering(file->tr, false);
 			if (test->ops->free)
-				test->ops->free(test->ops, test);
+				test->ops->free(test);
 		}
 	}
 }
 
 static int event_hist_trigger_parse(struct event_command *cmd_ops,
 				    struct trace_event_file *file,
-				    char *glob, char *cmd, char *param)
+				    char *glob, char *cmd,
+				    char *param_and_filter)
 {
 	unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
 	struct event_trigger_data *trigger_data;
 	struct hist_trigger_attrs *attrs;
-	struct event_trigger_ops *trigger_ops;
 	struct hist_trigger_data *hist_data;
+	char *param, *filter, *p, *start;
 	struct synth_event *se;
 	const char *se_name;
-	bool remove = false;
-	char *trigger, *p, *start;
+	bool remove;
 	int ret = 0;
 
 	lockdep_assert_held(&event_mutex);
 
-	WARN_ON(!glob);
-
-	if (strlen(glob)) {
-		hist_err_clear();
-		last_cmd_set(file, param);
-	}
-
-	if (!param)
+	if (WARN_ON(!glob))
 		return -EINVAL;
 
-	if (glob[0] == '!')
-		remove = true;
+	if (glob[0]) {
+		hist_err_clear();
+		last_cmd_set(file, param_and_filter);
+	}
+
+	remove = event_trigger_check_remove(glob);
+
+	if (event_trigger_empty_param(param_and_filter))
+		return -EINVAL;
 
 	/*
 	 * separate the trigger from the filter (k:v [if filter])
 	 * allowing for whitespace in the trigger
 	 */
-	p = trigger = param;
+	p = param = param_and_filter;
 	do {
 		p = strstr(p, "if");
 		if (!p)
 			break;
-		if (p == param)
+		if (p == param_and_filter)
 			return -EINVAL;
 		if (*(p - 1) != ' ' && *(p - 1) != '\t') {
 			p++;
 			continue;
 		}
-		if (p >= param + strlen(param) - (sizeof("if") - 1) - 1)
+		if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1)
 			return -EINVAL;
 		if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
 			p++;
···
 	} while (1);
 
 	if (!p)
-		param = NULL;
+		filter = NULL;
 	else {
 		*(p - 1) = '\0';
-		param = strstrip(p);
-		trigger = strstrip(trigger);
+		filter = strstrip(p);
+		param = strstrip(param);
 	}
 
 	/*
 	 * To simplify arithmetic expression parsing, replace occurrences of
 	 * '.sym-offset' modifier with '.symXoffset'
 	 */
-	start = strstr(trigger, ".sym-offset");
+	start = strstr(param, ".sym-offset");
 	while (start) {
 		*(start + 4) = 'X';
 		start = strstr(start + 11, ".sym-offset");
 	}
 
-	attrs = parse_hist_trigger_attrs(file->tr, trigger);
+	attrs = parse_hist_trigger_attrs(file->tr, param);
 	if (IS_ERR(attrs))
 		return PTR_ERR(attrs);
 
···
 		return PTR_ERR(hist_data);
 	}
 
-	trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
-
-	trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
+	trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data);
 	if (!trigger_data) {
 		ret = -ENOMEM;
 		goto out_free;
 	}
 
-	trigger_data->count = -1;
-	trigger_data->ops = trigger_ops;
-	trigger_data->cmd_ops = cmd_ops;
-
-	INIT_LIST_HEAD(&trigger_data->list);
-	RCU_INIT_POINTER(trigger_data->filter, NULL);
-
-	trigger_data->private_data = hist_data;
-
-	/* if param is non-empty, it's supposed to be a filter */
-	if (param && cmd_ops->set_filter) {
-		ret = cmd_ops->set_filter(param, trigger_data, file);
-		if (ret < 0)
-			goto out_free;
-	}
+	ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
+	if (ret < 0)
+		goto out_free;
 
 	if (remove) {
 		if (!have_hist_trigger_match(trigger_data, file))
···
 			goto out_free;
 		}
 
-		cmd_ops->unreg(glob+1, trigger_data, file);
+		event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
 		se_name = trace_event_name(file->event_call);
 		se = find_synth_event(se_name);
 		if (se)
···
 		goto out_free;
 	}
 
-	ret = cmd_ops->reg(glob, trigger_data, file);
-	/*
-	 * The above returns on success the # of triggers registered,
-	 * but if it didn't register any it returns zero.  Consider no
-	 * triggers registered a failure too.
-	 */
-	if (!ret) {
-		if (!(attrs->pause || attrs->cont || attrs->clear))
-			ret = -ENOENT;
+	if (existing_hist_update_only(glob, trigger_data, file))
 		goto out_free;
-	} else if (ret < 0)
+
+	ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
+	if (ret < 0)
 		goto out_free;
 
 	if (get_named_trigger_data(trigger_data))
···
 	se = find_synth_event(se_name);
 	if (se)
 		se->ref++;
-	/* Just return zero, not the number of registered triggers */
-	ret = 0;
  out:
 	if (ret == 0)
 		hist_err_clear();
 
 	return ret;
  out_unreg:
-	cmd_ops->unreg(glob+1, trigger_data, file);
+	event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
  out_free:
-	if (cmd_ops->set_filter)
-		cmd_ops->set_filter(NULL, trigger_data, NULL);
+	event_trigger_reset_filter(cmd_ops, trigger_data);
 
 	remove_hist_vars(hist_data);
 
···
 			update_cond_flag(file);
 			trace_event_trigger_enable_disable(file, 0);
 			if (test->ops->free)
-				test->ops->free(test->ops, test);
+				test->ops->free(test);
 		}
 	}
 }

kernel/trace/trace_events_trigger.c

···
 	}
 
 	data = list_entry(v, struct event_trigger_data, list);
-	data->ops->print(m, data->ops, data);
+	data->ops->print(m, data);
 
 	return 0;
 }
···
 
 /**
  * event_trigger_init - Generic event_trigger_ops @init implementation
- * @ops: The trigger ops associated with the trigger
  * @data: Trigger-specific data
  *
  * Common implementation of event trigger initialization.
···
  *
  * Return: 0 on success, errno otherwise
  */
-int event_trigger_init(struct event_trigger_ops *ops,
-		       struct event_trigger_data *data)
+int event_trigger_init(struct event_trigger_data *data)
 {
 	data->ref++;
 	return 0;
···
 
 /**
  * event_trigger_free - Generic event_trigger_ops @free implementation
- * @ops: The trigger ops associated with the trigger
  * @data: Trigger-specific data
  *
  * Common implementation of event trigger de-initialization.
···
  * implementations.
  */
 static void
-event_trigger_free(struct event_trigger_ops *ops,
-		   struct event_trigger_data *data)
+event_trigger_free(struct event_trigger_data *data)
 {
 	if (WARN_ON_ONCE(data->ref <= 0))
 		return;
···
 			trace_event_trigger_enable_disable(file, 0);
 			list_del_rcu(&data->list);
 			if (data->ops->free)
-				data->ops->free(data->ops, data);
+				data->ops->free(data);
 		}
 	}
 }
···
 	}
 
 	if (data->ops->init) {
-		ret = data->ops->init(data->ops, data);
+		ret = data->ops->init(data);
 		if (ret < 0)
 			goto out;
 	}
 
 	list_add_rcu(&data->list, &file->triggers);
-	ret++;
 
 	update_cond_flag(file);
-	if (trace_event_trigger_enable_disable(file, 1) < 0) {
+	ret = trace_event_trigger_enable_disable(file, 1);
+	if (ret < 0) {
 		list_del_rcu(&data->list);
 		update_cond_flag(file);
-		ret--;
 	}
 out:
 	return ret;
···
 			       struct event_trigger_data *test,
 			       struct trace_event_file *file)
 {
-	struct event_trigger_data *data;
-	bool unregistered = false;
+	struct event_trigger_data *data = NULL, *iter;
 
 	lockdep_assert_held(&event_mutex);
 
-	list_for_each_entry(data, &file->triggers, list) {
-		if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) {
-			unregistered = true;
+	list_for_each_entry(iter, &file->triggers, list) {
+		if (iter->cmd_ops->trigger_type == test->cmd_ops->trigger_type) {
+			data = iter;
 			list_del_rcu(&data->list);
 			trace_event_trigger_enable_disable(file, 0);
 			update_cond_flag(file);
···
 		}
 	}
 
-	if (unregistered && data->ops->free)
-		data->ops->free(data->ops, data);
+	if (data && data->ops->free)
+		data->ops->free(data);
 }
 
 /*
···
 
 /**
  * event_trigger_separate_filter - separate an event trigger from a filter
- * @param: The param string containing trigger and possibly filter
- * @trigger: outparam, will be filled with a pointer to the trigger
+ * @param_and_filter: String containing trigger and possibly filter
+ * @param: outparam, will be filled with a pointer to the trigger
  * @filter: outparam, will be filled with a pointer to the filter
  * @param_required: Specifies whether or not the param string is required
  *
  * Given a param string of the form '[trigger] [if filter]', this
  * function separates the filter from the trigger and returns the
- * trigger in *trigger and the filter in *filter.  Either the *trigger
- * or the *filter may be set to NULL by this function - if not set to
+ * trigger in @param and the filter in @filter.  Either the @param
+ * or the @filter may be set to NULL by this function - if not set to
  * NULL, they will contain strings corresponding to the trigger and
  * filter.
  *
···
  * @cmd_ops: The event_command operations for the trigger
  * @file: The event file for the trigger's event
  * @glob: The trigger command string, with optional remove(!) operator
- * @cmd: The cmd string
- * @param: The param string
  * @trigger_data: The trigger_data for the trigger
- * @n_registered: optional outparam, the number of triggers registered
  *
  * Register an event trigger.  The @cmd_ops are used to call the
- * cmd_ops->reg() function which actually does the registration. The
- * cmd_ops->reg() function returns the number of triggers registered,
- * which is assigned to n_registered, if n_registered is non-NULL.
+ * cmd_ops->reg() function which actually does the registration.
  *
  * Return: 0 on success, errno otherwise
  */
 int event_trigger_register(struct event_command *cmd_ops,
 			   struct trace_event_file *file,
 			   char *glob,
-			   char *cmd,
-			   char *param,
-			   struct event_trigger_data *trigger_data,
-			   int *n_registered)
+			   struct event_trigger_data *trigger_data)
 {
-	int ret;
+	return cmd_ops->reg(glob, trigger_data, file);
+}
 
-	if (n_registered)
-		*n_registered = 0;
-
-	ret = cmd_ops->reg(glob, trigger_data, file);
-	/*
-	 * The above returns on success the # of functions enabled,
-	 * but if it didn't find any functions it returns zero.
-	 * Consider no functions a failure too.
-	 */
-	if (!ret) {
-		cmd_ops->unreg(glob, trigger_data, file);
-		ret = -ENOENT;
-	} else if (ret > 0) {
-		if (n_registered)
-			*n_registered = ret;
-		/* Just return zero, not the number of enabled functions */
-		ret = 0;
-	}
-
-	return ret;
+/**
+ * event_trigger_unregister - unregister an event trigger
+ * @cmd_ops: The event_command operations for the trigger
+ * @file: The event file for the trigger's event
+ * @glob: The trigger command string, with optional remove(!) operator
+ * @trigger_data: The trigger_data for the trigger
+ *
+ * Unregister an event trigger.  The @cmd_ops are used to call the
+ * cmd_ops->unreg() function which actually does the unregistration.
+ */
+void event_trigger_unregister(struct event_command *cmd_ops,
+			      struct trace_event_file *file,
+			      char *glob,
+			      struct event_trigger_data *trigger_data)
+{
+	cmd_ops->unreg(glob, trigger_data, file);
 }
 
 /*
···
  * @file: The trace_event_file associated with the event
  * @glob: The raw string used to register the trigger
  * @cmd: The cmd portion of the string used to register the trigger
- * @param: The params portion of the string used to register the trigger
+ * @param_and_filter: The param and filter portion of the string used to register the trigger
  *
  * Common implementation for event command parsing and trigger
  * instantiation.
···
 static int
 event_trigger_parse(struct event_command *cmd_ops,
 		    struct trace_event_file *file,
-		    char *glob, char *cmd, char *param)
+		    char *glob, char *cmd, char *param_and_filter)
 {
 	struct event_trigger_data *trigger_data;
-	struct event_trigger_ops *trigger_ops;
-	char *trigger = NULL;
-	char *number;
+	char *param, *filter;
+	bool remove;
 	int ret;
 
-	/* separate the trigger from the filter (t:n [if filter]) */
-	if (param && isdigit(param[0])) {
-		trigger = strsep(&param, " \t");
-		if (param) {
-			param = skip_spaces(param);
-			if (!*param)
-				param = NULL;
-		}
-	}
+	remove = event_trigger_check_remove(glob);
 
-	trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
+	ret = event_trigger_separate_filter(param_and_filter, &param, &filter, false);
+	if (ret)
+		return ret;
 
 	ret = -ENOMEM;
-	trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
+	trigger_data = event_trigger_alloc(cmd_ops, cmd, param, file);
 	if (!trigger_data)
 		goto out;
 
-	trigger_data->count = -1;
-	trigger_data->ops = trigger_ops;
-	trigger_data->cmd_ops = cmd_ops;
-	trigger_data->private_data = file;
-	INIT_LIST_HEAD(&trigger_data->list);
-	INIT_LIST_HEAD(&trigger_data->named_list);
-
-	if (glob[0] == '!') {
-		cmd_ops->unreg(glob+1, trigger_data, file);
+	if (remove) {
+		event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
 		kfree(trigger_data);
 		ret = 0;
 		goto out;
 	}
 
-	if (trigger) {
-		number = strsep(&trigger, ":");
+	ret = event_trigger_parse_num(param, trigger_data);
+	if (ret)
+		goto out_free;
 
-		ret = -EINVAL;
-		if (!strlen(number))
-			goto out_free;
-
-		/*
-		 * We use the callback data field (which is a pointer)
-		 * as our counter.
-		 */
-		ret = kstrtoul(number, 0, &trigger_data->count);
-		if (ret)
-			goto out_free;
-	}
-
-	if (!param) /* if param is non-empty, it's supposed to be a filter */
-		goto out_reg;
-
-	if (!cmd_ops->set_filter)
-		goto out_reg;
-
-	ret = cmd_ops->set_filter(param, trigger_data, file);
+	ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
 	if (ret < 0)
 		goto out_free;
 
- out_reg:
 	/* Up the trigger_data count to make sure reg doesn't free it on failure */
-	event_trigger_init(trigger_ops, trigger_data);
-	ret = cmd_ops->reg(glob, trigger_data, file);
-	/*
-	 * The above returns on success the # of functions enabled,
-	 * but if it didn't find any functions it returns zero.
-	 * Consider no functions a failure too.
-	 */
-	if (!ret) {
-		cmd_ops->unreg(glob, trigger_data, file);
-		ret = -ENOENT;
-	} else if (ret > 0)
-		ret = 0;
+	event_trigger_init(trigger_data);
+
+	ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
+	if (ret)
+		goto out_free;
 
 	/* Down the counter of trigger_data or free it if not used anymore */
-	event_trigger_free(trigger_ops, trigger_data);
+	event_trigger_free(trigger_data);
  out:
 	return ret;
 
  out_free:
-	if (cmd_ops->set_filter)
-		cmd_ops->set_filter(NULL, trigger_data, NULL);
+	event_trigger_reset_filter(cmd_ops, trigger_data);
 	kfree(trigger_data);
 	goto out;
 }
···
 }
 
 static int
-traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
-		      struct event_trigger_data *data)
+traceon_trigger_print(struct seq_file *m, struct event_trigger_data *data)
 {
 	return event_trigger_print("traceon", m, (void *)data->count,
 				   data->filter_str);
 }
 
 static int
-traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
-		       struct event_trigger_data *data)
+traceoff_trigger_print(struct seq_file *m, struct event_trigger_data *data)
 {
 	return event_trigger_print("traceoff", m, (void *)data->count,
 				   data->filter_str);
···
 }
 
 static int
-snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
-		       struct event_trigger_data *data)
+snapshot_trigger_print(struct seq_file *m, struct event_trigger_data *data)
 {
 	return event_trigger_print("snapshot", m, (void *)data->count,
 				   data->filter_str);
···
 }
 
 static int
-stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
-			 struct event_trigger_data *data)
+stacktrace_trigger_print(struct seq_file *m, struct event_trigger_data *data)
 {
 	return event_trigger_print("stacktrace", m, (void *)data->count,
 				   data->filter_str);
···
 }
 
 int event_enable_trigger_print(struct seq_file *m,
-			       struct event_trigger_ops *ops,
 			       struct event_trigger_data *data)
 {
 	struct enable_trigger_data *enable_data = data->private_data;
···
 	return 0;
 }
 
-void event_enable_trigger_free(struct event_trigger_ops *ops,
-			       struct event_trigger_data *data)
+void event_enable_trigger_free(struct event_trigger_data *data)
 {
 	struct enable_trigger_data *enable_data = data->private_data;
 
···
 
 int event_enable_trigger_parse(struct event_command *cmd_ops,
 			       struct trace_event_file *file,
-			       char *glob, char *cmd, char *param)
+			       char *glob, char *cmd, char *param_and_filter)
 {
 	struct trace_event_file *event_enable_file;
 	struct enable_trigger_data *enable_data;
 	struct event_trigger_data *trigger_data;
-	struct event_trigger_ops *trigger_ops;
 	struct trace_array *tr = file->tr;
+	char *param, *filter;
+	bool enable, remove;
 	const char *system;
 	const char *event;
 	bool hist = false;
-	char *trigger;
-	char *number;
-	bool enable;
 	int ret;
 
+	remove = event_trigger_check_remove(glob);
+
+	if (event_trigger_empty_param(param_and_filter))
+		return -EINVAL;
+
+	ret = event_trigger_separate_filter(param_and_filter, &param, &filter, true);
+	if (ret)
+		return ret;
+
+	system = strsep(&param, ":");
 	if (!param)
 		return -EINVAL;
 
-	/* separate the trigger from the filter (s:e:n [if filter]) */
-	trigger = strsep(&param, " \t");
-	if (!trigger)
-		return -EINVAL;
-	if (param) {
-		param = skip_spaces(param);
-		if (!*param)
-			param = NULL;
-	}
-
-	system = strsep(&trigger, ":");
-	if (!trigger)
-		return -EINVAL;
-
-	event = strsep(&trigger, ":");
+	event = strsep(&param, ":");
 
 	ret = -EINVAL;
 	event_enable_file = find_event_file(tr, system, event);
···
 #else
 	enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
 #endif
-	trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
-
 	ret = -ENOMEM;
-	trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
-	if (!trigger_data)
-		goto out;
 
 	enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL);
-	if (!enable_data) {
-		kfree(trigger_data);
+	if (!enable_data)
 		goto out;
-	}
-
-	trigger_data->count = -1;
-	trigger_data->ops = trigger_ops;
-	trigger_data->cmd_ops = cmd_ops;
-	INIT_LIST_HEAD(&trigger_data->list);
-	RCU_INIT_POINTER(trigger_data->filter, NULL);
 
 	enable_data->hist = hist;
 	enable_data->enable = enable;
 	enable_data->file = event_enable_file;
-	trigger_data->private_data = enable_data;
 
-	if (glob[0] == '!') {
-		cmd_ops->unreg(glob+1, trigger_data, file);
+	trigger_data = event_trigger_alloc(cmd_ops, cmd, param, enable_data);
+	if (!trigger_data) {
+		kfree(enable_data);
+		goto out;
+	}
+
+	if (remove) {
+		event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
 		kfree(trigger_data);
 		kfree(enable_data);
 		ret = 0;
···
 	}
 
 	/* Up the trigger_data count to make sure nothing frees it on failure */
-	event_trigger_init(trigger_ops, trigger_data);
+	event_trigger_init(trigger_data);
 
-	if (trigger) {
-		number = strsep(&trigger, ":");
+	ret = event_trigger_parse_num(param, trigger_data);
+	if (ret)
+		goto out_free;
 
-		ret = -EINVAL;
-		if (!strlen(number))
-			goto out_free;
-
-		/*
-		 * We use the callback data field (which is a pointer)
-		 * as our counter.
-		 */
-		ret = kstrtoul(number, 0, &trigger_data->count);
-		if (ret)
-			goto out_free;
-	}
-
-	if (!param) /* if param is non-empty, it's supposed to be a filter */
-		goto out_reg;
-
-	if (!cmd_ops->set_filter)
-		goto out_reg;
-
-	ret = cmd_ops->set_filter(param, trigger_data, file);
+	ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
 	if (ret < 0)
 		goto out_free;
 
- out_reg:
 	/* Don't let event modules unload while probe registered */
 	ret = trace_event_try_get_ref(event_enable_file->event_call);
 	if (!ret) {
···
 	ret = trace_event_enable_disable(event_enable_file, 1, 1);
 	if (ret < 0)
 		goto out_put;
-	ret = cmd_ops->reg(glob, trigger_data, file);
-	/*
-	 * The above returns on success the # of functions enabled,
-	 * but if it didn't find any functions it returns zero.
-	 * Consider no functions a failure too.
-	 */
-	if (!ret) {
-		ret = -ENOENT;
+
+	ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
+	if (ret)
 		goto out_disable;
-	} else if (ret < 0)
-		goto out_disable;
-	/* Just return zero, not the number of enabled functions */
-	ret = 0;
-	event_trigger_free(trigger_ops, trigger_data);
+
+	event_trigger_free(trigger_data);
  out:
 	return ret;
-
  out_disable:
 	trace_event_enable_disable(event_enable_file, 0, 1);
  out_put:
 	trace_event_put_ref(event_enable_file->event_call);
  out_free:
-	if (cmd_ops->set_filter)
-		cmd_ops->set_filter(NULL, trigger_data, NULL);
-	event_trigger_free(trigger_ops, trigger_data);
+	event_trigger_reset_filter(cmd_ops, trigger_data);
+	event_trigger_free(trigger_data);
 	kfree(enable_data);
+
 	goto out;
 }
 
···
 	}
 
 	if (data->ops->init) {
-		ret = data->ops->init(data->ops, data);
+		ret = data->ops->init(data);
 		if (ret < 0)
 			goto out;
 	}
 
 	list_add_rcu(&data->list, &file->triggers);
-	ret++;
 
 	update_cond_flag(file);
-	if (trace_event_trigger_enable_disable(file, 1) < 0) {
+	ret = trace_event_trigger_enable_disable(file, 1);
+	if (ret < 0) {
 		list_del_rcu(&data->list);
 		update_cond_flag(file);
-		ret--;
 	}
 out:
 	return ret;
···
 				     struct trace_event_file *file)
 {
 	struct enable_trigger_data *test_enable_data = test->private_data;
+	struct event_trigger_data *data = NULL, *iter;
 	struct enable_trigger_data *enable_data;
-	struct event_trigger_data *data;
-	bool unregistered = false;
 
 	lockdep_assert_held(&event_mutex);
 
-	list_for_each_entry(data, &file->triggers, list) {
-		enable_data = data->private_data;
+	list_for_each_entry(iter, &file->triggers, list) {
+		enable_data = iter->private_data;
 		if (enable_data &&
-		    (data->cmd_ops->trigger_type ==
+		    (iter->cmd_ops->trigger_type ==
 		     test->cmd_ops->trigger_type) &&
 		    (enable_data->file == test_enable_data->file)) {
-			unregistered = true;
+			data = iter;
 			list_del_rcu(&data->list);
 			trace_event_trigger_enable_disable(file, 0);
 			update_cond_flag(file);
···
 		}
 	}
 
-	if (unregistered && data->ops->free)
-		data->ops->free(data->ops, data);
+	if (data && data->ops->free)
+		data->ops->free(data);
 }
 
 static struct event_trigger_ops *

kernel/trace/trace_kprobe.c

···
 static __init int init_kprobe_trace(void)
 {
 	int ret;
-	struct dentry *entry;
 
 	ret = tracing_init_dentry();
 	if (ret)
 		return 0;
 
-	entry = tracefs_create_file("kprobe_events", TRACE_MODE_WRITE,
-				    NULL, NULL, &kprobe_events_ops);
-
 	/* Event list interface */
-	if (!entry)
-		pr_warn("Could not create tracefs 'kprobe_events' entry\n");
+	trace_create_file("kprobe_events", TRACE_MODE_WRITE,
+			  NULL, NULL, &kprobe_events_ops);
 
 	/* Profile interface */
-	entry = tracefs_create_file("kprobe_profile", TRACE_MODE_READ,
-				    NULL, NULL, &kprobe_profile_ops);
-
-	if (!entry)
-		pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
+	trace_create_file("kprobe_profile", TRACE_MODE_READ,
+			  NULL, NULL, &kprobe_profile_ops);
 
 	setup_boot_kprobe_events();
 

kernel/trace/trace_osnoise.c

···
 
 	trace_timerlat_sample(&s);
 
-	notify_new_max_latency(diff);
+	if (osnoise_data.stop_tracing) {
+		if (time_to_us(diff) >= osnoise_data.stop_tracing) {
 
-	if (osnoise_data.stop_tracing)
-		if (time_to_us(diff) >= osnoise_data.stop_tracing)
+			/*
+			 * At this point, if stop_tracing is set and <= print_stack,
+			 * print_stack is set and would be printed in the thread handler.
+			 *
+			 * Thus, print the stack trace as it is helpful to define the
+			 * root cause of an IRQ latency.
+			 */
+			if (osnoise_data.stop_tracing <= osnoise_data.print_stack) {
+				timerlat_save_stack(0);
+				timerlat_dump_stack(time_to_us(diff));
+			}
+
 			osnoise_stop_tracing();
+			notify_new_max_latency(diff);
+
+			return HRTIMER_NORESTART;
+		}
+	}
 
 	wake_up_process(tlat->kthread);
 

kernel/trace/trace_output.c

···
 
 static int trace_search_list(struct list_head **list)
 {
-	struct trace_event *e;
+	struct trace_event *e = NULL, *iter;
 	int next = __TRACE_LAST_TYPE;
 
 	if (list_empty(&ftrace_event_list)) {
···
 	 * We used up all possible max events,
 	 * lets see if somebody freed one.
 	 */
-	list_for_each_entry(e, &ftrace_event_list, list) {
-		if (e->type != next)
+	list_for_each_entry(iter, &ftrace_event_list, list) {
+		if (iter->type != next) {
+			e = iter;
 			break;
+		}
 		next++;
 	}
 
···
 	if (next > TRACE_EVENT_TYPE_MAX)
 		return 0;
 
-	*list = &e->list;
+	if (e)
+		*list = &e->list;
+	else
+		*list = &ftrace_event_list;
 	return next;
 }
 
···
 
 		list_add_tail(&event->list, list);
 
-	} else if (event->type > __TRACE_LAST_TYPE) {
-		printk(KERN_WARNING "Need to add type to trace.h\n");
-		WARN_ON(1);
+	} else if (WARN(event->type > __TRACE_LAST_TYPE,
+			"Need to add type to trace.h")) {
 		goto out;
 	} else {
 		/* Is this event already used */
···
 
 	for (i = 0; events[i]; i++) {
 		event = events[i];
-
 		ret = register_trace_event(event);
-		if (!ret) {
-			printk(KERN_WARNING "event %d failed to register\n",
-			       event->type);
-			WARN_ON_ONCE(1);
-		}
+		WARN_ONCE(!ret, "event %d failed to register", event->type);
 	}
 
 	return 0;

kernel/trace/trace_recursion_record.c

···
 
 __init static int create_recursed_functions(void)
 {
-	struct dentry *dentry;
 
-	dentry = trace_create_file("recursed_functions", TRACE_MODE_WRITE,
-				   NULL, NULL, &recursed_functions_fops);
-	if (!dentry)
-		pr_warn("WARNING: Failed to create recursed_functions\n");
+	trace_create_file("recursed_functions", TRACE_MODE_WRITE,
+			  NULL, NULL, &recursed_functions_fops);
 	return 0;
 }
 

kernel/trace/trace_selftest.c

···
 		ret = -1;
 		goto out;
 	}
+
+	/* Enable tracing on all functions again */
+	ftrace_set_global_filter(NULL, 0, 1);
 #endif
 
 	/* Don't test dynamic tracing, the function tracer already did */

kernel/trace/trace_syscalls.c

···
 			goto end;
 
 		/* parameter types */
-		if (tr->trace_flags & TRACE_ITER_VERBOSE)
+		if (tr && tr->trace_flags & TRACE_ITER_VERBOSE)
 			trace_seq_printf(s, "%s ", entry->types[i]);
 
 		/* parameter values */
···
 	struct trace_event_file *trace_file;
 	struct syscall_trace_enter *entry;
 	struct syscall_metadata *sys_data;
-	struct ring_buffer_event *event;
-	struct trace_buffer *buffer;
-	unsigned int trace_ctx;
+	struct trace_event_buffer fbuffer;
 	unsigned long args[6];
 	int syscall_nr;
 	int size;
···
 
 	size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
 
-	trace_ctx = tracing_gen_ctx();
-
-	event = trace_event_buffer_lock_reserve(&buffer, trace_file,
-			sys_data->enter_event->event.type, size, trace_ctx);
-	if (!event)
+	entry = trace_event_buffer_reserve(&fbuffer, trace_file, size);
+	if (!entry)
 		return;
 
-	entry = ring_buffer_event_data(event);
+	entry = ring_buffer_event_data(fbuffer.event);
 	entry->nr = syscall_nr;
 	syscall_get_arguments(current, regs, args);
 	memcpy(entry->args, args, sizeof(unsigned long) * sys_data->nb_args);
 
-	event_trigger_unlock_commit(trace_file, buffer, event, entry,
-				    trace_ctx);
+	trace_event_buffer_commit(&fbuffer);
 }
 
 static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
···
 	struct trace_event_file *trace_file;
 	struct syscall_trace_exit *entry;
 	struct syscall_metadata *sys_data;
-	struct ring_buffer_event *event;
-	struct trace_buffer *buffer;
-	unsigned int trace_ctx;
+	struct trace_event_buffer fbuffer;
 	int syscall_nr;
 
 	syscall_nr = trace_get_syscall_nr(current, regs);
···
 	if (!sys_data)
 		return;
 
-	trace_ctx = tracing_gen_ctx();
-
-	event = trace_event_buffer_lock_reserve(&buffer, trace_file,
-			sys_data->exit_event->event.type, sizeof(*entry),
-			trace_ctx);
-	if (!event)
+	entry = trace_event_buffer_reserve(&fbuffer, trace_file, sizeof(*entry));
+	if (!entry)
 		return;
 
-	entry = ring_buffer_event_data(event);
+	entry = ring_buffer_event_data(fbuffer.event);
 	entry->nr = syscall_nr;
 	entry->ret = syscall_get_return_value(current, regs);
 
-	event_trigger_unlock_commit(trace_file, buffer, event, entry,
-				    trace_ctx);
+	trace_event_buffer_commit(&fbuffer);
 }
 
 static int reg_event_syscall_enter(struct trace_event_file *file,

kernel/trace/tracing_map.c

···
 /**
  * tracing_map_sort_entries - Sort the current set of tracing_map_elts in a map
  * @map: The tracing_map
- * @sort_key: The sort key to use for sorting
+ * @sort_keys: The sort key to use for sorting
+ * @n_sort_keys: hitcount, always have at least one
  * @sort_entries: outval: pointer to allocated and sorted array of entries
  *
  * tracing_map_sort_entries() sorts the current set of entries in the

lib/.gitignore

···
 # SPDX-License-Identifier: GPL-2.0-only
 /crc32table.h
 /crc64table.h
+/default.bconf
 /gen_crc32table
 /gen_crc64table
 /oid_registry_data.c

lib/Makefile

···
 	$(eval CFLAGS_$(file) = -I $(srctree)/scripts/dtc/libfdt))
 lib-$(CONFIG_LIBFDT) += $(libfdt_files)
 
-lib-$(CONFIG_BOOT_CONFIG) += bootconfig.o
+obj-$(CONFIG_BOOT_CONFIG) += bootconfig.o
+obj-$(CONFIG_BOOT_CONFIG_EMBED) += bootconfig-data.o
+
+$(obj)/bootconfig-data.o: $(obj)/default.bconf
+
+targets += default.bconf
+filechk_defbconf = cat $(or $(real-prereqs), /dev/null)
+$(obj)/default.bconf: $(CONFIG_BOOT_CONFIG_EMBED_FILE) FORCE
+	$(call filechk,defbconf)
 
 obj-$(CONFIG_RBTREE_TEST) += rbtree_test.o
 obj-$(CONFIG_INTERVAL_TREE_TEST) += interval_tree_test.o

lib/bootconfig-data.S

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Embed default bootconfig in the kernel.
+ */
+	.section .init.rodata, "aw"
+	.global embedded_bootconfig_data
+embedded_bootconfig_data:
+	.incbin "lib/default.bconf"
+	.global embedded_bootconfig_data_end
+embedded_bootconfig_data_end:

lib/bootconfig.c

···
 #include <linux/kernel.h>
 #include <linux/memblock.h>
 #include <linux/string.h>
+
+#ifdef CONFIG_BOOT_CONFIG_EMBED
+/* embedded_bootconfig_data is defined in bootconfig-data.S */
+extern __visible const char embedded_bootconfig_data[];
+extern __visible const char embedded_bootconfig_data_end[];
+
+const char * __init xbc_get_embedded_bootconfig(size_t *size)
+{
+	*size = embedded_bootconfig_data_end - embedded_bootconfig_data;
+	return (*size) ? embedded_bootconfig_data : NULL;
+}
+#endif
+
 #else /* !__KERNEL__ */
 /*
  * NOTE: This is only for tools/bootconfig, because tools/bootconfig will