Commit | Line | Data |
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2521f2c2 PO |
1 | /* |
2 | * This code maintains a list of active profiling data structures. | |
3 | * | |
4 | * Copyright IBM Corp. 2009 | |
5 | * Author(s): Peter Oberparleiter <oberpar@linux.vnet.ibm.com> | |
6 | * | |
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 | |
14 | */ | |
15 | ||
16 | #define pr_fmt(fmt) "gcov: " fmt | |
17 | ||
18 | #include <linux/init.h> | |
19 | #include <linux/module.h> | |
20 | #include <linux/mutex.h> | |
9d796e66 | 21 | #include <linux/sched.h> |
2521f2c2 PO |
22 | #include "gcov.h" |
23 | ||
2521f2c2 PO |
24 | static int gcov_events_enabled; |
25 | static DEFINE_MUTEX(gcov_lock); | |
26 | ||
27 | /* | |
28 | * __gcov_init is called by gcc-generated constructor code for each object | |
29 | * file compiled with -fprofile-arcs. | |
30 | */ | |
31 | void __gcov_init(struct gcov_info *info) | |
32 | { | |
33 | static unsigned int gcov_version; | |
34 | ||
35 | mutex_lock(&gcov_lock); | |
36 | if (gcov_version == 0) { | |
8cbce376 | 37 | gcov_version = gcov_info_version(info); |
2521f2c2 PO |
38 | /* |
39 | * Printing gcc's version magic may prove useful for debugging | |
40 | * incompatibility reports. | |
41 | */ | |
42 | pr_info("version magic: 0x%x\n", gcov_version); | |
43 | } | |
44 | /* | |
45 | * Add new profiling data structure to list and inform event | |
46 | * listener. | |
47 | */ | |
8cbce376 | 48 | gcov_info_link(info); |
2521f2c2 PO |
49 | if (gcov_events_enabled) |
50 | gcov_event(GCOV_ADD, info); | |
51 | mutex_unlock(&gcov_lock); | |
52 | } | |
53 | EXPORT_SYMBOL(__gcov_init); | |
54 | ||
55 | /* | |
56 | * These functions may be referenced by gcc-generated profiling code but serve | |
57 | * no function for kernel profiling. | |
58 | */ | |
59 | void __gcov_flush(void) | |
60 | { | |
61 | /* Unused. */ | |
62 | } | |
63 | EXPORT_SYMBOL(__gcov_flush); | |
64 | ||
65 | void __gcov_merge_add(gcov_type *counters, unsigned int n_counters) | |
66 | { | |
67 | /* Unused. */ | |
68 | } | |
69 | EXPORT_SYMBOL(__gcov_merge_add); | |
70 | ||
71 | void __gcov_merge_single(gcov_type *counters, unsigned int n_counters) | |
72 | { | |
73 | /* Unused. */ | |
74 | } | |
75 | EXPORT_SYMBOL(__gcov_merge_single); | |
76 | ||
77 | void __gcov_merge_delta(gcov_type *counters, unsigned int n_counters) | |
78 | { | |
79 | /* Unused. */ | |
80 | } | |
81 | EXPORT_SYMBOL(__gcov_merge_delta); | |
82 | ||
5f41ea03 FH |
83 | void __gcov_merge_ior(gcov_type *counters, unsigned int n_counters) |
84 | { | |
85 | /* Unused. */ | |
86 | } | |
87 | EXPORT_SYMBOL(__gcov_merge_ior); | |
88 | ||
a992bf83 YP |
89 | void __gcov_merge_time_profile(gcov_type *counters, unsigned int n_counters) |
90 | { | |
91 | /* Unused. */ | |
92 | } | |
93 | EXPORT_SYMBOL(__gcov_merge_time_profile); | |
94 | ||
2521f2c2 PO |
95 | /** |
96 | * gcov_enable_events - enable event reporting through gcov_event() | |
97 | * | |
98 | * Turn on reporting of profiling data load/unload-events through the | |
99 | * gcov_event() callback. Also replay all previous events once. This function | |
100 | * is needed because some events are potentially generated too early for the | |
101 | * callback implementation to handle them initially. | |
102 | */ | |
103 | void gcov_enable_events(void) | |
104 | { | |
8cbce376 | 105 | struct gcov_info *info = NULL; |
2521f2c2 PO |
106 | |
107 | mutex_lock(&gcov_lock); | |
108 | gcov_events_enabled = 1; | |
8cbce376 | 109 | |
2521f2c2 | 110 | /* Perform event callback for previously registered entries. */ |
9d796e66 | 111 | while ((info = gcov_info_next(info))) { |
2521f2c2 | 112 | gcov_event(GCOV_ADD, info); |
9d796e66 AR |
113 | cond_resched(); |
114 | } | |
8cbce376 | 115 | |
2521f2c2 PO |
116 | mutex_unlock(&gcov_lock); |
117 | } | |
118 | ||
119 | #ifdef CONFIG_MODULES | |
120 | static inline int within(void *addr, void *start, unsigned long size) | |
121 | { | |
122 | return ((addr >= start) && (addr < start + size)); | |
123 | } | |
124 | ||
125 | /* Update list and generate events when modules are unloaded. */ | |
126 | static int gcov_module_notifier(struct notifier_block *nb, unsigned long event, | |
127 | void *data) | |
128 | { | |
129 | struct module *mod = data; | |
8cbce376 FH |
130 | struct gcov_info *info = NULL; |
131 | struct gcov_info *prev = NULL; | |
2521f2c2 PO |
132 | |
133 | if (event != MODULE_STATE_GOING) | |
134 | return NOTIFY_OK; | |
135 | mutex_lock(&gcov_lock); | |
8cbce376 | 136 | |
2521f2c2 | 137 | /* Remove entries located in module from linked list. */ |
8cbce376 | 138 | while ((info = gcov_info_next(info))) { |
2521f2c2 | 139 | if (within(info, mod->module_core, mod->core_size)) { |
8cbce376 | 140 | gcov_info_unlink(prev, info); |
2521f2c2 PO |
141 | if (gcov_events_enabled) |
142 | gcov_event(GCOV_REMOVE, info); | |
143 | } else | |
144 | prev = info; | |
145 | } | |
8cbce376 | 146 | |
2521f2c2 PO |
147 | mutex_unlock(&gcov_lock); |
148 | ||
149 | return NOTIFY_OK; | |
150 | } | |
151 | ||
152 | static struct notifier_block gcov_nb = { | |
153 | .notifier_call = gcov_module_notifier, | |
154 | }; | |
155 | ||
156 | static int __init gcov_init(void) | |
157 | { | |
158 | return register_module_notifier(&gcov_nb); | |
159 | } | |
160 | device_initcall(gcov_init); | |
161 | #endif /* CONFIG_MODULES */ |