summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/platforms/cell/spufs/sputrace.c
blob: d0b1f3f4d9c887de9a902b4e511c0a2940a4aa02 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
/*
 * Copyright (C) 2007 IBM Deutschland Entwicklung GmbH
 *	Released under GPL v2.
 *
 * Partially based on net/ipv4/tcp_probe.c.
 *
 * Simple tracing facility for spu contexts.
 */
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/marker.h>
#include <linux/proc_fs.h>
#include <linux/wait.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>
#include "spufs.h"

struct spu_probe {
	const char *name;
	const char *format;
	marker_probe_func *probe_func;
};

struct sputrace {
	ktime_t tstamp;
	int owner_tid; /* owner */
	int curr_tid;
	const char *name;
	int number;
};

static int bufsize __read_mostly = 16384;
MODULE_PARM_DESC(bufsize, "Log buffer size (number of records)");
module_param(bufsize, int, 0);


static DEFINE_SPINLOCK(sputrace_lock);
static DECLARE_WAIT_QUEUE_HEAD(sputrace_wait);
static ktime_t sputrace_start;
static unsigned long sputrace_head, sputrace_tail;
static struct sputrace *sputrace_log;
static int sputrace_logging;

static int sputrace_used(void)
{
	return (sputrace_head - sputrace_tail) % bufsize;
}

static inline int sputrace_avail(void)
{
	return bufsize - sputrace_used();
}

static int sputrace_sprint(char *tbuf, int n)
{
	const struct sputrace *t = sputrace_log + sputrace_tail % bufsize;
	struct timespec tv =
		ktime_to_timespec(ktime_sub(t->tstamp, sputrace_start));

	return snprintf(tbuf, n,
		"[%lu.%09lu] %d: %s (ctxthread = %d, spu = %d)\n",
		(unsigned long) tv.tv_sec,
		(unsigned long) tv.tv_nsec,
		t->curr_tid,
		t->name,
		t->owner_tid,
		t->number);
}

static ssize_t sputrace_read(struct file *file, char __user *buf,
		size_t len, loff_t *ppos)
{
	int error = 0, cnt = 0;

	if (!buf || len < 0)
		return -EINVAL;

	while (cnt < len) {
		char tbuf[128];
		int width;

		/* If we have data ready to return, don't block waiting
		 * for more */
		if (cnt > 0 && sputrace_used() == 0)
			break;

		error = wait_event_interruptible(sputrace_wait,
						 sputrace_used() > 0);
		if (error)
			break;

		spin_lock(&sputrace_lock);
		if (sputrace_head == sputrace_tail) {
			spin_unlock(&sputrace_lock);
			continue;
		}

		width = sputrace_sprint(tbuf, sizeof(tbuf));
		if (width < len)
			sputrace_tail = (sputrace_tail + 1) % bufsize;
		spin_unlock(&sputrace_lock);

		if (width >= len)
			break;

		error = copy_to_user(buf + cnt, tbuf, width);
		if (error)
			break;
		cnt += width;
	}

	return cnt == 0 ? error : cnt;
}

static int sputrace_open(struct inode *inode, struct file *file)
{
	int rc;

	spin_lock(&sputrace_lock);
	if (sputrace_logging) {
		rc = -EBUSY;
		goto out;
	}

	sputrace_logging = 1;
	sputrace_head = sputrace_tail = 0;
	sputrace_start = ktime_get();
	rc = 0;

out:
	spin_unlock(&sputrace_lock);
	return rc;
}

static int sputrace_release(struct inode *inode, struct file *file)
{
	spin_lock(&sputrace_lock);
	sputrace_logging = 0;
	spin_unlock(&sputrace_lock);
	return 0;
}

static const struct file_operations sputrace_fops = {
	.owner   = THIS_MODULE,
	.open    = sputrace_open,
	.read    = sputrace_read,
	.release = sputrace_release,
};

static void sputrace_log_item(const char *name, struct spu_context *ctx,
		struct spu *spu)
{
	spin_lock(&sputrace_lock);

	if (!sputrace_logging) {
		spin_unlock(&sputrace_lock);
		return;
	}

	if (sputrace_avail() > 1) {
		struct sputrace *t = sputrace_log + sputrace_head;

		t->tstamp = ktime_get();
		t->owner_tid = ctx->tid;
		t->name = name;
		t->curr_tid = current->pid;
		t->number = spu ? spu->number : -1;

		sputrace_head = (sputrace_head + 1) % bufsize;
	} else {
		printk(KERN_WARNING
		       "sputrace: lost samples due to full buffer.\n");
	}
	spin_unlock(&sputrace_lock);

	wake_up(&sputrace_wait);
}

static void spu_context_event(void *probe_private, void *call_data,
		const char *format, va_list *args)
{
	struct spu_probe *p = probe_private;
	struct spu_context *ctx;
	struct spu *spu;

	ctx = va_arg(*args, struct spu_context *);
	spu = va_arg(*args, struct spu *);

	sputrace_log_item(p->name, ctx, spu);
}

static void spu_context_nospu_event(void *probe_private, void *call_data,
		const char *format, va_list *args)
{
	struct spu_probe *p = probe_private;
	struct spu_context *ctx;

	ctx = va_arg(*args, struct spu_context *);

	sputrace_log_item(p->name, ctx, NULL);
}

struct spu_probe spu_probes[] = {
	{ "spu_bind_context__enter", "ctx %p spu %p", spu_context_event },
	{ "spu_unbind_context__enter", "ctx %p spu %p", spu_context_event },
	{ "spu_get_idle__enter", "ctx %p", spu_context_nospu_event },
	{ "spu_get_idle__found", "ctx %p spu %p", spu_context_event },
	{ "spu_get_idle__not_found", "ctx %p", spu_context_nospu_event },
	{ "spu_find_victim__enter", "ctx %p", spu_context_nospu_event },
	{ "spusched_tick__preempt", "ctx %p spu %p", spu_context_event },
	{ "spusched_tick__newslice", "ctx %p", spu_context_nospu_event },
	{ "spu_yield__enter", "ctx %p", spu_context_nospu_event },
	{ "spu_deactivate__enter", "ctx %p", spu_context_nospu_event },
	{ "__spu_deactivate__unload", "ctx %p spu %p", spu_context_event },
	{ "spufs_ps_fault__enter", "ctx %p", spu_context_nospu_event },
	{ "spufs_ps_fault__sleep", "ctx %p", spu_context_nospu_event },
	{ "spufs_ps_fault__wake", "ctx %p spu %p", spu_context_event },
	{ "spufs_ps_fault__insert", "ctx %p spu %p", spu_context_event },
	{ "spu_acquire_saved__enter", "ctx %p", spu_context_nospu_event },
	{ "destroy_spu_context__enter", "ctx %p", spu_context_nospu_event },
	{ "spufs_stop_callback__enter", "ctx %p spu %p", spu_context_event },
};

static int __init sputrace_init(void)
{
	struct proc_dir_entry *entry;
	int i, error = -ENOMEM;

	sputrace_log = kcalloc(bufsize, sizeof(struct sputrace), GFP_KERNEL);
	if (!sputrace_log)
		goto out;

	entry = proc_create("sputrace", S_IRUSR, NULL, &sputrace_fops);
	if (!entry)
		goto out_free_log;

	for (i = 0; i < ARRAY_SIZE(spu_probes); i++) {
		struct spu_probe *p = &spu_probes[i];

		error = marker_probe_register(p->name, p->format,
					      p->probe_func, p);
		if (error)
			printk(KERN_INFO "Unable to register probe %s\n",
					p->name);
	}

	return 0;

out_free_log:
	kfree(sputrace_log);
out:
	return -ENOMEM;
}

static void __exit sputrace_exit(void)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(spu_probes); i++)
		marker_probe_unregister(spu_probes[i].name,
			spu_probes[i].probe_func, &spu_probes[i]);

	remove_proc_entry("sputrace", NULL);
	kfree(sputrace_log);
	marker_synchronize_unregister();
}

module_init(sputrace_init);
module_exit(sputrace_exit);

MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud