| 1 | /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1) |
| 2 | * |
| 3 | * wrapper/ftrace.h |
| 4 | * |
| 5 | * wrapper around vmalloc_sync_all. Using KALLSYMS to get its address when |
| 6 | * available, else we need to have a kernel that exports this function to GPL |
| 7 | * modules. |
| 8 | * |
| 9 | * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 10 | */ |
| 11 | |
| 12 | #ifndef _LTTNG_WRAPPER_FTRACE_H |
| 13 | #define _LTTNG_WRAPPER_FTRACE_H |
| 14 | |
| 15 | #include <linux/ftrace.h> |
| 16 | #include <linux/version.h> |
| 17 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,12,0)) |
| 18 | #include <../kernel/trace/trace.h> |
| 19 | #endif |
| 20 | |
| 21 | #ifdef CONFIG_KALLSYMS |
| 22 | |
| 23 | #include <linux/kallsyms.h> |
| 24 | #include <wrapper/kallsyms.h> |
| 25 | |
| 26 | static inline |
| 27 | int wrapper_register_ftrace_function_probe(char *glob, |
| 28 | struct ftrace_probe_ops *ops, void *data) |
| 29 | { |
| 30 | int (*register_ftrace_function_probe_sym)(char *glob, |
| 31 | struct ftrace_probe_ops *ops, void *data); |
| 32 | |
| 33 | register_ftrace_function_probe_sym = (void *) kallsyms_lookup_funcptr("register_ftrace_function_probe"); |
| 34 | if (register_ftrace_function_probe_sym) { |
| 35 | return register_ftrace_function_probe_sym(glob, ops, data); |
| 36 | } else { |
| 37 | printk_once(KERN_WARNING "LTTng: register_ftrace_function_probe symbol lookup failed.\n"); |
| 38 | return -EINVAL; |
| 39 | } |
| 40 | } |
| 41 | |
| 42 | static inline |
| 43 | void wrapper_unregister_ftrace_function_probe(char *glob, |
| 44 | struct ftrace_probe_ops *ops, void *data) |
| 45 | { |
| 46 | void (*unregister_ftrace_function_probe_sym)(char *glob, |
| 47 | struct ftrace_probe_ops *ops, void *data); |
| 48 | |
| 49 | unregister_ftrace_function_probe_sym = (void *) kallsyms_lookup_funcptr("unregister_ftrace_function_probe"); |
| 50 | if (unregister_ftrace_function_probe_sym) { |
| 51 | unregister_ftrace_function_probe_sym(glob, ops, data); |
| 52 | } else { |
| 53 | printk_once(KERN_WARNING "LTTng: unregister_ftrace_function_probe symbol lookup failed.\n"); |
| 54 | WARN_ON(1); |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | #else |
| 59 | |
| 60 | static inline |
| 61 | int wrapper_register_ftrace_function_probe(char *glob, |
| 62 | struct ftrace_probe_ops *ops, void *data) |
| 63 | { |
| 64 | return register_ftrace_function_probe(glob, ops, data); |
| 65 | } |
| 66 | |
| 67 | static inline |
| 68 | void wrapper_unregister_ftrace_function_probe(char *glob, |
| 69 | struct ftrace_probe_ops *ops, void *data) |
| 70 | { |
| 71 | return unregister_ftrace_function_probe(glob, ops, data); |
| 72 | } |
| 73 | #endif |
| 74 | |
| 75 | #endif /* _LTTNG_WRAPPER_FTRACE_H */ |