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Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
21783c97 MS |
2 | #include <linux/init.h> |
3 | #include <linux/errno.h> | |
4 | #include <linux/kernel.h> | |
5 | #include <linux/proc_fs.h> | |
5a0e3ad6 | 6 | #include <linux/slab.h> |
21783c97 MS |
7 | #include <linux/types.h> |
8 | #include <asm/ptrace.h> | |
7c0f6ba6 | 9 | #include <linux/uaccess.h> |
21783c97 MS |
10 | |
11 | #define SAMPLE_BUFFER_SIZE 8192 | |
12 | ||
c1c8f558 JN |
13 | static char *sample_buffer; |
14 | static char *sample_buffer_pos; | |
21783c97 MS |
15 | static int prof_running = 0; |
16 | ||
c1c8f558 | 17 | void cris_profile_sample(struct pt_regs *regs) |
21783c97 | 18 | { |
542401d9 CG |
19 | 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 | ||
c1c8f558 | 27 | *(unsigned int *)(sample_buffer_pos + 4) = instruction_pointer(regs); |
542401d9 CG |
28 | sample_buffer_pos += 8; |
29 | ||
30 | if (sample_buffer_pos == sample_buffer + SAMPLE_BUFFER_SIZE) | |
31 | sample_buffer_pos = sample_buffer; | |
21783c97 MS |
32 | } |
33 | ||
34 | static ssize_t | |
542401d9 CG |
35 | read_cris_profile(struct file *file, char __user *buf, |
36 | size_t count, loff_t *ppos) | |
21783c97 | 37 | { |
542401d9 | 38 | unsigned long p = *ppos; |
ed62f77b | 39 | ssize_t ret; |
542401d9 | 40 | |
ed62f77b AM |
41 | ret = simple_read_from_buffer(buf, count, ppos, sample_buffer, |
42 | SAMPLE_BUFFER_SIZE); | |
43 | if (ret < 0) | |
44 | return ret; | |
542401d9 | 45 | |
ed62f77b | 46 | memset(sample_buffer + p, 0, ret); |
542401d9 | 47 | |
ed62f77b | 48 | return ret; |
21783c97 MS |
49 | } |
50 | ||
51 | static ssize_t | |
52 | write_cris_profile(struct file *file, const char __user *buf, | |
542401d9 | 53 | size_t count, loff_t *ppos) |
21783c97 | 54 | { |
542401d9 CG |
55 | sample_buffer_pos = sample_buffer; |
56 | memset(sample_buffer, 0, SAMPLE_BUFFER_SIZE); | |
c1c8f558 | 57 | return count < SAMPLE_BUFFER_SIZE ? count : SAMPLE_BUFFER_SIZE; |
21783c97 MS |
58 | } |
59 | ||
5dfe4c96 | 60 | static const struct file_operations cris_proc_profile_operations = { |
21783c97 MS |
61 | .read = read_cris_profile, |
62 | .write = write_cris_profile, | |
6038f373 | 63 | .llseek = default_llseek, |
21783c97 MS |
64 | }; |
65 | ||
c1c8f558 | 66 | static int __init init_cris_profile(void) |
21783c97 | 67 | { |
542401d9 CG |
68 | struct proc_dir_entry *entry; |
69 | ||
70 | sample_buffer = kmalloc(SAMPLE_BUFFER_SIZE, GFP_KERNEL); | |
71 | if (!sample_buffer) { | |
72 | return -ENOMEM; | |
73 | } | |
74 | ||
75 | sample_buffer_pos = sample_buffer; | |
76 | ||
c293819a DL |
77 | entry = proc_create("system_profile", S_IWUSR | S_IRUGO, NULL, |
78 | &cris_proc_profile_operations); | |
542401d9 | 79 | if (entry) { |
254844d3 | 80 | proc_set_size(entry, SAMPLE_BUFFER_SIZE); |
542401d9 CG |
81 | } |
82 | prof_running = 1; | |
83 | ||
84 | return 0; | |
21783c97 | 85 | } |
21783c97 | 86 | __initcall(init_cris_profile); |
c1c8f558 | 87 |