blob: b917549a7d94b72735fb461d7a213f8a68da8f1e [file] [log] [blame]
Mikael Starvik21783c92005-07-27 11:44:40 -07001#include <linux/init.h>
2#include <linux/errno.h>
3#include <linux/kernel.h>
4#include <linux/proc_fs.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +09005#include <linux/slab.h>
Mikael Starvik21783c92005-07-27 11:44:40 -07006#include <linux/types.h>
7#include <asm/ptrace.h>
8#include <asm/uaccess.h>
9
10#define SAMPLE_BUFFER_SIZE 8192
11
12static char* sample_buffer;
13static char* sample_buffer_pos;
14static int prof_running = 0;
15
16void
17cris_profile_sample(struct pt_regs* regs)
18{
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070019 if (!prof_running)
20 return;
21
22 if (user_mode(regs))
23 *(unsigned int*)sample_buffer_pos = current->pid;
24 else
25 *(unsigned int*)sample_buffer_pos = 0;
26
27 *(unsigned int*)(sample_buffer_pos + 4) = instruction_pointer(regs);
28 sample_buffer_pos += 8;
29
30 if (sample_buffer_pos == sample_buffer + SAMPLE_BUFFER_SIZE)
31 sample_buffer_pos = sample_buffer;
Mikael Starvik21783c92005-07-27 11:44:40 -070032}
33
34static ssize_t
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070035read_cris_profile(struct file *file, char __user *buf,
36 size_t count, loff_t *ppos)
Mikael Starvik21783c92005-07-27 11:44:40 -070037{
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070038 unsigned long p = *ppos;
Akinobu Mitaed62f772008-07-23 21:28:46 -070039 ssize_t ret;
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070040
Akinobu Mitaed62f772008-07-23 21:28:46 -070041 ret = simple_read_from_buffer(buf, count, ppos, sample_buffer,
42 SAMPLE_BUFFER_SIZE);
43 if (ret < 0)
44 return ret;
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070045
Akinobu Mitaed62f772008-07-23 21:28:46 -070046 memset(sample_buffer + p, 0, ret);
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070047
Akinobu Mitaed62f772008-07-23 21:28:46 -070048 return ret;
Mikael Starvik21783c92005-07-27 11:44:40 -070049}
50
51static ssize_t
52write_cris_profile(struct file *file, const char __user *buf,
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070053 size_t count, loff_t *ppos)
Mikael Starvik21783c92005-07-27 11:44:40 -070054{
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070055 sample_buffer_pos = sample_buffer;
56 memset(sample_buffer, 0, SAMPLE_BUFFER_SIZE);
Mikael Starvik21783c92005-07-27 11:44:40 -070057}
58
Arjan van de Ven5dfe4c92007-02-12 00:55:31 -080059static const struct file_operations cris_proc_profile_operations = {
Mikael Starvik21783c92005-07-27 11:44:40 -070060 .read = read_cris_profile,
61 .write = write_cris_profile,
62};
63
64static int
65__init init_cris_profile(void)
66{
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070067 struct proc_dir_entry *entry;
68
69 sample_buffer = kmalloc(SAMPLE_BUFFER_SIZE, GFP_KERNEL);
70 if (!sample_buffer) {
71 return -ENOMEM;
72 }
73
74 sample_buffer_pos = sample_buffer;
75
Denis V. Lunevc2938192008-04-29 01:02:23 -070076 entry = proc_create("system_profile", S_IWUSR | S_IRUGO, NULL,
77 &cris_proc_profile_operations);
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070078 if (entry) {
Cyrill Gorcunov542401d2007-05-06 14:50:56 -070079 entry->size = SAMPLE_BUFFER_SIZE;
80 }
81 prof_running = 1;
82
83 return 0;
Mikael Starvik21783c92005-07-27 11:44:40 -070084}
85
86__initcall(init_cris_profile);