aboutsummaryrefslogtreecommitdiffstats
path: root/mm/kmemtrace.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/kmemtrace.c')
-rw-r--r--mm/kmemtrace.c333
1 files changed, 0 insertions, 333 deletions
diff --git a/mm/kmemtrace.c b/mm/kmemtrace.c
deleted file mode 100644
index 0573b5080cc4..000000000000
--- a/mm/kmemtrace.c
+++ /dev/null
@@ -1,333 +0,0 @@
1/*
2 * Copyright (C) 2008 Pekka Enberg, Eduard - Gabriel Munteanu
3 *
4 * This file is released under GPL version 2.
5 */
6
7#include <linux/string.h>
8#include <linux/debugfs.h>
9#include <linux/relay.h>
10#include <linux/module.h>
11#include <linux/marker.h>
12#include <linux/gfp.h>
13#include <trace/kmemtrace.h>
14
15#define KMEMTRACE_SUBBUF_SIZE 524288
16#define KMEMTRACE_DEF_N_SUBBUFS 20
17
18static struct rchan *kmemtrace_chan;
19static u32 kmemtrace_buf_overruns;
20
21static unsigned int kmemtrace_n_subbufs;
22
23/* disabled by default */
24static unsigned int kmemtrace_enabled;
25
26/*
27 * The sequence number is used for reordering kmemtrace packets
28 * in userspace, since they are logged as per-CPU data.
29 *
30 * atomic_t should always be a 32-bit signed integer. Wraparound is not
31 * likely to occur, but userspace can deal with it by expecting a certain
32 * sequence number in the next packet that will be read.
33 */
34static atomic_t kmemtrace_seq_num;
35
36#define KMEMTRACE_ABI_VERSION 1
37
38static u32 kmemtrace_abi_version __read_mostly = KMEMTRACE_ABI_VERSION;
39
40enum kmemtrace_event_id {
41 KMEMTRACE_EVENT_ALLOC = 0,
42 KMEMTRACE_EVENT_FREE,
43};
44
45struct kmemtrace_event {
46 u8 event_id;
47 u8 type_id;
48 u16 event_size;
49 s32 seq_num;
50 u64 call_site;
51 u64 ptr;
52} __attribute__ ((__packed__));
53
54struct kmemtrace_stats_alloc {
55 u64 bytes_req;
56 u64 bytes_alloc;
57 u32 gfp_flags;
58 s32 numa_node;
59} __attribute__ ((__packed__));
60
61static void kmemtrace_probe_alloc(void *probe_data, void *call_data,
62 const char *format, va_list *args)
63{
64 unsigned long flags;
65 struct kmemtrace_event *ev;
66 struct kmemtrace_stats_alloc *stats;
67 void *buf;
68
69 local_irq_save(flags);
70
71 buf = relay_reserve(kmemtrace_chan,
72 sizeof(struct kmemtrace_event) +
73 sizeof(struct kmemtrace_stats_alloc));
74 if (!buf)
75 goto failed;
76
77 /*
78 * Don't convert this to use structure initializers,
79 * C99 does not guarantee the rvalues evaluation order.
80 */
81
82 ev = buf;
83 ev->event_id = KMEMTRACE_EVENT_ALLOC;
84 ev->type_id = va_arg(*args, int);
85 ev->event_size = sizeof(struct kmemtrace_event) +
86 sizeof(struct kmemtrace_stats_alloc);
87 ev->seq_num = atomic_add_return(1, &kmemtrace_seq_num);
88 ev->call_site = va_arg(*args, unsigned long);
89 ev->ptr = va_arg(*args, unsigned long);
90
91 stats = buf + sizeof(struct kmemtrace_event);
92 stats->bytes_req = va_arg(*args, unsigned long);
93 stats->bytes_alloc = va_arg(*args, unsigned long);
94 stats->gfp_flags = va_arg(*args, unsigned long);
95 stats->numa_node = va_arg(*args, int);
96
97failed:
98 local_irq_restore(flags);
99}
100
101static void kmemtrace_probe_free(void *probe_data, void *call_data,
102 const char *format, va_list *args)
103{
104 unsigned long flags;
105 struct kmemtrace_event *ev;
106
107 local_irq_save(flags);
108
109 ev = relay_reserve(kmemtrace_chan, sizeof(struct kmemtrace_event));
110 if (!ev)
111 goto failed;
112
113 /*
114 * Don't convert this to use structure initializers,
115 * C99 does not guarantee the rvalues evaluation order.
116 */
117 ev->event_id = KMEMTRACE_EVENT_FREE;
118 ev->type_id = va_arg(*args, int);
119 ev->event_size = sizeof(struct kmemtrace_event);
120 ev->seq_num = atomic_add_return(1, &kmemtrace_seq_num);
121 ev->call_site = va_arg(*args, unsigned long);
122 ev->ptr = va_arg(*args, unsigned long);
123
124failed:
125 local_irq_restore(flags);
126}
127
128static struct dentry *
129kmemtrace_create_buf_file(const char *filename, struct dentry *parent,
130 int mode, struct rchan_buf *buf, int *is_global)
131{
132 return debugfs_create_file(filename, mode, parent, buf,
133 &relay_file_operations);
134}
135
136static int kmemtrace_remove_buf_file(struct dentry *dentry)
137{
138 debugfs_remove(dentry);
139
140 return 0;
141}
142
143static int kmemtrace_subbuf_start(struct rchan_buf *buf,
144 void *subbuf,
145 void *prev_subbuf,
146 size_t prev_padding)
147{
148 if (relay_buf_full(buf)) {
149 /*
150 * We know it's not SMP-safe, but neither
151 * debugfs_create_u32() is.
152 */
153 kmemtrace_buf_overruns++;
154 return 0;
155 }
156
157 return 1;
158}
159
160static struct rchan_callbacks relay_callbacks = {
161 .create_buf_file = kmemtrace_create_buf_file,
162 .remove_buf_file = kmemtrace_remove_buf_file,
163 .subbuf_start = kmemtrace_subbuf_start,
164};
165
166static struct dentry *kmemtrace_dir;
167static struct dentry *kmemtrace_overruns_dentry;
168static struct dentry *kmemtrace_abi_version_dentry;
169
170static struct dentry *kmemtrace_enabled_dentry;
171
172static int kmemtrace_start_probes(void)
173{
174 int err;
175
176 err = marker_probe_register("kmemtrace_alloc", "type_id %d "
177 "call_site %lu ptr %lu "
178 "bytes_req %lu bytes_alloc %lu "
179 "gfp_flags %lu node %d",
180 kmemtrace_probe_alloc, NULL);
181 if (err)
182 return err;
183 err = marker_probe_register("kmemtrace_free", "type_id %d "
184 "call_site %lu ptr %lu",
185 kmemtrace_probe_free, NULL);
186
187 return err;
188}
189
190static void kmemtrace_stop_probes(void)
191{
192 marker_probe_unregister("kmemtrace_alloc",
193 kmemtrace_probe_alloc, NULL);
194 marker_probe_unregister("kmemtrace_free",
195 kmemtrace_probe_free, NULL);
196}
197
198static int kmemtrace_enabled_get(void *data, u64 *val)
199{
200 *val = *((int *) data);
201
202 return 0;
203}
204
205static int kmemtrace_enabled_set(void *data, u64 val)
206{
207 u64 old_val = kmemtrace_enabled;
208
209 *((int *) data) = !!val;
210
211 if (old_val == val)
212 return 0;
213 if (val)
214 kmemtrace_start_probes();
215 else
216 kmemtrace_stop_probes();
217
218 return 0;
219}
220
221DEFINE_SIMPLE_ATTRIBUTE(kmemtrace_enabled_fops,
222 kmemtrace_enabled_get,
223 kmemtrace_enabled_set, "%llu\n");
224
225static void kmemtrace_cleanup(void)
226{
227 if (kmemtrace_enabled_dentry)
228 debugfs_remove(kmemtrace_enabled_dentry);
229
230 kmemtrace_stop_probes();
231
232 if (kmemtrace_abi_version_dentry)
233 debugfs_remove(kmemtrace_abi_version_dentry);
234 if (kmemtrace_overruns_dentry)
235 debugfs_remove(kmemtrace_overruns_dentry);
236
237 relay_close(kmemtrace_chan);
238 kmemtrace_chan = NULL;
239
240 if (kmemtrace_dir)
241 debugfs_remove(kmemtrace_dir);
242}
243
244static int __init kmemtrace_setup_late(void)
245{
246 if (!kmemtrace_chan)
247 goto failed;
248
249 kmemtrace_dir = debugfs_create_dir("kmemtrace", NULL);
250 if (!kmemtrace_dir)
251 goto cleanup;
252
253 kmemtrace_abi_version_dentry =
254 debugfs_create_u32("abi_version", S_IRUSR,
255 kmemtrace_dir, &kmemtrace_abi_version);
256 kmemtrace_overruns_dentry =
257 debugfs_create_u32("total_overruns", S_IRUSR,
258 kmemtrace_dir, &kmemtrace_buf_overruns);
259 if (!kmemtrace_overruns_dentry || !kmemtrace_abi_version_dentry)
260 goto cleanup;
261
262 kmemtrace_enabled_dentry =
263 debugfs_create_file("enabled", S_IRUSR | S_IWUSR,
264 kmemtrace_dir, &kmemtrace_enabled,
265 &kmemtrace_enabled_fops);
266 if (!kmemtrace_enabled_dentry)
267 goto cleanup;
268
269 if (relay_late_setup_files(kmemtrace_chan, "cpu", kmemtrace_dir))
270 goto cleanup;
271
272 printk(KERN_INFO "kmemtrace: fully up.\n");
273
274 return 0;
275
276cleanup:
277 kmemtrace_cleanup();
278failed:
279 return 1;
280}
281late_initcall(kmemtrace_setup_late);
282
283static int __init kmemtrace_set_boot_enabled(char *str)
284{
285 if (!str)
286 return -EINVAL;
287
288 if (!strcmp(str, "yes"))
289 kmemtrace_enabled = 1;
290 else if (!strcmp(str, "no"))
291 kmemtrace_enabled = 0;
292 else
293 return -EINVAL;
294
295 return 0;
296}
297early_param("kmemtrace.enable", kmemtrace_set_boot_enabled);
298
299static int __init kmemtrace_set_subbufs(char *str)
300{
301 get_option(&str, &kmemtrace_n_subbufs);
302 return 0;
303}
304early_param("kmemtrace.subbufs", kmemtrace_set_subbufs);
305
306void kmemtrace_init(void)
307{
308 if (!kmemtrace_n_subbufs)
309 kmemtrace_n_subbufs = KMEMTRACE_DEF_N_SUBBUFS;
310
311 kmemtrace_chan = relay_open(NULL, NULL, KMEMTRACE_SUBBUF_SIZE,
312 kmemtrace_n_subbufs, &relay_callbacks,
313 NULL);
314 if (!kmemtrace_chan) {
315 printk(KERN_ERR "kmemtrace: could not open relay channel.\n");
316 return;
317 }
318
319 if (!kmemtrace_enabled) {
320 printk(KERN_INFO "kmemtrace: disabled. Pass "
321 "kemtrace.enable=yes as kernel parameter for "
322 "boot-time tracing.\n");
323 return;
324 }
325 if (kmemtrace_start_probes()) {
326 printk(KERN_ERR "kmemtrace: could not register marker probes!\n");
327 kmemtrace_cleanup();
328 return;
329 }
330
331 printk(KERN_INFO "kmemtrace: enabled.\n");
332}
333
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-14 16:51:23 -0500