Merge tag 'locks-v3.16-2' of git://git.samba.org/jlayton/linux
[linux/fpc-iii.git] / kernel / gcov / base.c
blobb358a802fd184391ae4926bc02b2983511bc8077
1 /*
2 * This code maintains a list of active profiling data structures.
4 * Copyright IBM Corp. 2009
5 * Author(s): Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
7 * Uses gcc-internal data definitions.
8 * Based on the gcov-kernel patch by:
9 * Hubertus Franke <frankeh@us.ibm.com>
10 * Nigel Hinds <nhinds@us.ibm.com>
11 * Rajan Ravindran <rajancr@us.ibm.com>
12 * Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
13 * Paul Larson
16 #define pr_fmt(fmt) "gcov: " fmt
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/mutex.h>
21 #include "gcov.h"
23 static int gcov_events_enabled;
24 static DEFINE_MUTEX(gcov_lock);
27 * __gcov_init is called by gcc-generated constructor code for each object
28 * file compiled with -fprofile-arcs.
30 void __gcov_init(struct gcov_info *info)
32 static unsigned int gcov_version;
34 mutex_lock(&gcov_lock);
35 if (gcov_version == 0) {
36 gcov_version = gcov_info_version(info);
38 * Printing gcc's version magic may prove useful for debugging
39 * incompatibility reports.
41 pr_info("version magic: 0x%x\n", gcov_version);
44 * Add new profiling data structure to list and inform event
45 * listener.
47 gcov_info_link(info);
48 if (gcov_events_enabled)
49 gcov_event(GCOV_ADD, info);
50 mutex_unlock(&gcov_lock);
52 EXPORT_SYMBOL(__gcov_init);
55 * These functions may be referenced by gcc-generated profiling code but serve
56 * no function for kernel profiling.
58 void __gcov_flush(void)
60 /* Unused. */
62 EXPORT_SYMBOL(__gcov_flush);
64 void __gcov_merge_add(gcov_type *counters, unsigned int n_counters)
66 /* Unused. */
68 EXPORT_SYMBOL(__gcov_merge_add);
70 void __gcov_merge_single(gcov_type *counters, unsigned int n_counters)
72 /* Unused. */
74 EXPORT_SYMBOL(__gcov_merge_single);
76 void __gcov_merge_delta(gcov_type *counters, unsigned int n_counters)
78 /* Unused. */
80 EXPORT_SYMBOL(__gcov_merge_delta);
82 void __gcov_merge_ior(gcov_type *counters, unsigned int n_counters)
84 /* Unused. */
86 EXPORT_SYMBOL(__gcov_merge_ior);
88 void __gcov_merge_time_profile(gcov_type *counters, unsigned int n_counters)
90 /* Unused. */
92 EXPORT_SYMBOL(__gcov_merge_time_profile);
94 /**
95 * gcov_enable_events - enable event reporting through gcov_event()
97 * Turn on reporting of profiling data load/unload-events through the
98 * gcov_event() callback. Also replay all previous events once. This function
99 * is needed because some events are potentially generated too early for the
100 * callback implementation to handle them initially.
102 void gcov_enable_events(void)
104 struct gcov_info *info = NULL;
106 mutex_lock(&gcov_lock);
107 gcov_events_enabled = 1;
109 /* Perform event callback for previously registered entries. */
110 while ((info = gcov_info_next(info)))
111 gcov_event(GCOV_ADD, info);
113 mutex_unlock(&gcov_lock);
116 #ifdef CONFIG_MODULES
117 static inline int within(void *addr, void *start, unsigned long size)
119 return ((addr >= start) && (addr < start + size));
122 /* Update list and generate events when modules are unloaded. */
123 static int gcov_module_notifier(struct notifier_block *nb, unsigned long event,
124 void *data)
126 struct module *mod = data;
127 struct gcov_info *info = NULL;
128 struct gcov_info *prev = NULL;
130 if (event != MODULE_STATE_GOING)
131 return NOTIFY_OK;
132 mutex_lock(&gcov_lock);
134 /* Remove entries located in module from linked list. */
135 while ((info = gcov_info_next(info))) {
136 if (within(info, mod->module_core, mod->core_size)) {
137 gcov_info_unlink(prev, info);
138 if (gcov_events_enabled)
139 gcov_event(GCOV_REMOVE, info);
140 } else
141 prev = info;
144 mutex_unlock(&gcov_lock);
146 return NOTIFY_OK;
149 static struct notifier_block gcov_nb = {
150 .notifier_call = gcov_module_notifier,
153 static int __init gcov_init(void)
155 return register_module_notifier(&gcov_nb);
157 device_initcall(gcov_init);
158 #endif /* CONFIG_MODULES */