diff options
author | Ingo Molnar <mingo@elte.hu> | 2009-04-08 11:25:42 -0400 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-04-08 11:26:00 -0400 |
commit | 5af8c4e0fac9838428bd718040b664043a05f37c (patch) | |
tree | 75a01d98ed244db45fe3c734c4a81c1a3d92ac37 /kernel/trace/trace_printk.c | |
parent | 46e0bb9c12f4bab539736f1714cbf16600f681ec (diff) | |
parent | 577c9c456f0e1371cbade38eaf91ae8e8a308555 (diff) |
Merge commit 'v2.6.30-rc1' into sched/urgent
Merge reason: update to latest upstream to queue up fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace/trace_printk.c')
-rw-r--r-- | kernel/trace/trace_printk.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c new file mode 100644 index 000000000000..eb81556107fe --- /dev/null +++ b/kernel/trace/trace_printk.c | |||
@@ -0,0 +1,270 @@ | |||
1 | /* | ||
2 | * trace binary printk | ||
3 | * | ||
4 | * Copyright (C) 2008 Lai Jiangshan <laijs@cn.fujitsu.com> | ||
5 | * | ||
6 | */ | ||
7 | #include <linux/seq_file.h> | ||
8 | #include <linux/debugfs.h> | ||
9 | #include <linux/uaccess.h> | ||
10 | #include <linux/kernel.h> | ||
11 | #include <linux/ftrace.h> | ||
12 | #include <linux/string.h> | ||
13 | #include <linux/module.h> | ||
14 | #include <linux/marker.h> | ||
15 | #include <linux/mutex.h> | ||
16 | #include <linux/ctype.h> | ||
17 | #include <linux/list.h> | ||
18 | #include <linux/slab.h> | ||
19 | #include <linux/fs.h> | ||
20 | |||
21 | #include "trace.h" | ||
22 | |||
23 | #ifdef CONFIG_MODULES | ||
24 | |||
25 | /* | ||
26 | * modules trace_printk()'s formats are autosaved in struct trace_bprintk_fmt | ||
27 | * which are queued on trace_bprintk_fmt_list. | ||
28 | */ | ||
29 | static LIST_HEAD(trace_bprintk_fmt_list); | ||
30 | |||
31 | /* serialize accesses to trace_bprintk_fmt_list */ | ||
32 | static DEFINE_MUTEX(btrace_mutex); | ||
33 | |||
34 | struct trace_bprintk_fmt { | ||
35 | struct list_head list; | ||
36 | char fmt[0]; | ||
37 | }; | ||
38 | |||
39 | static inline struct trace_bprintk_fmt *lookup_format(const char *fmt) | ||
40 | { | ||
41 | struct trace_bprintk_fmt *pos; | ||
42 | list_for_each_entry(pos, &trace_bprintk_fmt_list, list) { | ||
43 | if (!strcmp(pos->fmt, fmt)) | ||
44 | return pos; | ||
45 | } | ||
46 | return NULL; | ||
47 | } | ||
48 | |||
49 | static | ||
50 | void hold_module_trace_bprintk_format(const char **start, const char **end) | ||
51 | { | ||
52 | const char **iter; | ||
53 | |||
54 | mutex_lock(&btrace_mutex); | ||
55 | for (iter = start; iter < end; iter++) { | ||
56 | struct trace_bprintk_fmt *tb_fmt = lookup_format(*iter); | ||
57 | if (tb_fmt) { | ||
58 | *iter = tb_fmt->fmt; | ||
59 | continue; | ||
60 | } | ||
61 | |||
62 | tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt) | ||
63 | + strlen(*iter) + 1, GFP_KERNEL); | ||
64 | if (tb_fmt) { | ||
65 | list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list); | ||
66 | strcpy(tb_fmt->fmt, *iter); | ||
67 | *iter = tb_fmt->fmt; | ||
68 | } else | ||
69 | *iter = NULL; | ||
70 | } | ||
71 | mutex_unlock(&btrace_mutex); | ||
72 | } | ||
73 | |||
74 | static int module_trace_bprintk_format_notify(struct notifier_block *self, | ||
75 | unsigned long val, void *data) | ||
76 | { | ||
77 | struct module *mod = data; | ||
78 | if (mod->num_trace_bprintk_fmt) { | ||
79 | const char **start = mod->trace_bprintk_fmt_start; | ||
80 | const char **end = start + mod->num_trace_bprintk_fmt; | ||
81 | |||
82 | if (val == MODULE_STATE_COMING) | ||
83 | hold_module_trace_bprintk_format(start, end); | ||
84 | } | ||
85 | return 0; | ||
86 | } | ||
87 | |||
88 | #else /* !CONFIG_MODULES */ | ||
89 | __init static int | ||
90 | module_trace_bprintk_format_notify(struct notifier_block *self, | ||
91 | unsigned long val, void *data) | ||
92 | { | ||
93 | return 0; | ||
94 | } | ||
95 | #endif /* CONFIG_MODULES */ | ||
96 | |||
97 | |||
98 | __initdata_or_module static | ||
99 | struct notifier_block module_trace_bprintk_format_nb = { | ||
100 | .notifier_call = module_trace_bprintk_format_notify, | ||
101 | }; | ||
102 | |||
103 | int __trace_bprintk(unsigned long ip, const char *fmt, ...) | ||
104 | { | ||
105 | int ret; | ||
106 | va_list ap; | ||
107 | |||
108 | if (unlikely(!fmt)) | ||
109 | return 0; | ||
110 | |||
111 | if (!(trace_flags & TRACE_ITER_PRINTK)) | ||
112 | return 0; | ||
113 | |||
114 | va_start(ap, fmt); | ||
115 | ret = trace_vbprintk(ip, fmt, ap); | ||
116 | va_end(ap); | ||
117 | return ret; | ||
118 | } | ||
119 | EXPORT_SYMBOL_GPL(__trace_bprintk); | ||
120 | |||
121 | int __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap) | ||
122 | { | ||
123 | if (unlikely(!fmt)) | ||
124 | return 0; | ||
125 | |||
126 | if (!(trace_flags & TRACE_ITER_PRINTK)) | ||
127 | return 0; | ||
128 | |||
129 | return trace_vbprintk(ip, fmt, ap); | ||
130 | } | ||
131 | EXPORT_SYMBOL_GPL(__ftrace_vbprintk); | ||
132 | |||
133 | int __trace_printk(unsigned long ip, const char *fmt, ...) | ||
134 | { | ||
135 | int ret; | ||
136 | va_list ap; | ||
137 | |||
138 | if (!(trace_flags & TRACE_ITER_PRINTK)) | ||
139 | return 0; | ||
140 | |||
141 | va_start(ap, fmt); | ||
142 | ret = trace_vprintk(ip, fmt, ap); | ||
143 | va_end(ap); | ||
144 | return ret; | ||
145 | } | ||
146 | EXPORT_SYMBOL_GPL(__trace_printk); | ||
147 | |||
148 | int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) | ||
149 | { | ||
150 | if (!(trace_flags & TRACE_ITER_PRINTK)) | ||
151 | return 0; | ||
152 | |||
153 | return trace_vprintk(ip, fmt, ap); | ||
154 | } | ||
155 | EXPORT_SYMBOL_GPL(__ftrace_vprintk); | ||
156 | |||
157 | static void * | ||
158 | t_next(struct seq_file *m, void *v, loff_t *pos) | ||
159 | { | ||
160 | const char **fmt = m->private; | ||
161 | const char **next = fmt; | ||
162 | |||
163 | (*pos)++; | ||
164 | |||
165 | if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt) | ||
166 | return NULL; | ||
167 | |||
168 | next = fmt; | ||
169 | m->private = ++next; | ||
170 | |||
171 | return fmt; | ||
172 | } | ||
173 | |||
174 | static void *t_start(struct seq_file *m, loff_t *pos) | ||
175 | { | ||
176 | return t_next(m, NULL, pos); | ||
177 | } | ||
178 | |||
179 | static int t_show(struct seq_file *m, void *v) | ||
180 | { | ||
181 | const char **fmt = v; | ||
182 | const char *str = *fmt; | ||
183 | int i; | ||
184 | |||
185 | seq_printf(m, "0x%lx : \"", (unsigned long)fmt); | ||
186 | |||
187 | /* | ||
188 | * Tabs and new lines need to be converted. | ||
189 | */ | ||
190 | for (i = 0; str[i]; i++) { | ||
191 | switch (str[i]) { | ||
192 | case '\n': | ||
193 | seq_puts(m, "\\n"); | ||
194 | break; | ||
195 | case '\t': | ||
196 | seq_puts(m, "\\t"); | ||
197 | break; | ||
198 | case '\\': | ||
199 | seq_puts(m, "\\"); | ||
200 | break; | ||
201 | case '"': | ||
202 | seq_puts(m, "\\\""); | ||
203 | break; | ||
204 | default: | ||
205 | seq_putc(m, str[i]); | ||
206 | } | ||
207 | } | ||
208 | seq_puts(m, "\"\n"); | ||
209 | |||
210 | return 0; | ||
211 | } | ||
212 | |||
213 | static void t_stop(struct seq_file *m, void *p) | ||
214 | { | ||
215 | } | ||
216 | |||
217 | static const struct seq_operations show_format_seq_ops = { | ||
218 | .start = t_start, | ||
219 | .next = t_next, | ||
220 | .show = t_show, | ||
221 | .stop = t_stop, | ||
222 | }; | ||
223 | |||
224 | static int | ||
225 | ftrace_formats_open(struct inode *inode, struct file *file) | ||
226 | { | ||
227 | int ret; | ||
228 | |||
229 | ret = seq_open(file, &show_format_seq_ops); | ||
230 | if (!ret) { | ||
231 | struct seq_file *m = file->private_data; | ||
232 | |||
233 | m->private = __start___trace_bprintk_fmt; | ||
234 | } | ||
235 | return ret; | ||
236 | } | ||
237 | |||
238 | static const struct file_operations ftrace_formats_fops = { | ||
239 | .open = ftrace_formats_open, | ||
240 | .read = seq_read, | ||
241 | .llseek = seq_lseek, | ||
242 | .release = seq_release, | ||
243 | }; | ||
244 | |||
245 | static __init int init_trace_printk_function_export(void) | ||
246 | { | ||
247 | struct dentry *d_tracer; | ||
248 | struct dentry *entry; | ||
249 | |||
250 | d_tracer = tracing_init_dentry(); | ||
251 | if (!d_tracer) | ||
252 | return 0; | ||
253 | |||
254 | entry = debugfs_create_file("printk_formats", 0444, d_tracer, | ||
255 | NULL, &ftrace_formats_fops); | ||
256 | if (!entry) | ||
257 | pr_warning("Could not create debugfs " | ||
258 | "'printk_formats' entry\n"); | ||
259 | |||
260 | return 0; | ||
261 | } | ||
262 | |||
263 | fs_initcall(init_trace_printk_function_export); | ||
264 | |||
265 | static __init int init_trace_printk(void) | ||
266 | { | ||
267 | return register_module_notifier(&module_trace_bprintk_format_nb); | ||
268 | } | ||
269 | |||
270 | early_initcall(init_trace_printk); | ||