1 /*
2 * f2fs IO tracer
3 *
4 * Copyright (c) 2014 Motorola Mobility
5 * Copyright (c) 2014 Jaegeuk Kim <jaegeuk@kernel.org>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11 #include <linux/fs.h>
12 #include <linux/f2fs_fs.h>
13 #include <linux/sched.h>
14 #include <linux/radix-tree.h>
15
16 #include "f2fs.h"
17 #include "trace.h"
18
19 static RADIX_TREE(pids, GFP_ATOMIC);
20 static spinlock_t pids_lock;
21 static struct last_io_info last_io;
22
__print_last_io(void)23 static inline void __print_last_io(void)
24 {
25 if (!last_io.len)
26 return;
27
28 trace_printk("%3x:%3x %4x %-16s %2x %5x %12x %4x\n",
29 last_io.major, last_io.minor,
30 last_io.pid, "----------------",
31 last_io.type,
32 last_io.fio.rw, last_io.fio.blk_addr,
33 last_io.len);
34 memset(&last_io, 0, sizeof(last_io));
35 }
36
__file_type(struct inode * inode,pid_t pid)37 static int __file_type(struct inode *inode, pid_t pid)
38 {
39 if (f2fs_is_atomic_file(inode))
40 return __ATOMIC_FILE;
41 else if (f2fs_is_volatile_file(inode))
42 return __VOLATILE_FILE;
43 else if (S_ISDIR(inode->i_mode))
44 return __DIR_FILE;
45 else if (inode->i_ino == F2FS_NODE_INO(F2FS_I_SB(inode)))
46 return __NODE_FILE;
47 else if (inode->i_ino == F2FS_META_INO(F2FS_I_SB(inode)))
48 return __META_FILE;
49 else if (pid)
50 return __NORMAL_FILE;
51 else
52 return __MISC_FILE;
53 }
54
f2fs_trace_pid(struct page * page)55 void f2fs_trace_pid(struct page *page)
56 {
57 struct inode *inode = page->mapping->host;
58 pid_t pid = task_pid_nr(current);
59 void *p;
60
61 page->private = pid;
62
63 if (radix_tree_preload(GFP_NOFS))
64 return;
65
66 spin_lock(&pids_lock);
67 p = radix_tree_lookup(&pids, pid);
68 if (p == current)
69 goto out;
70 if (p)
71 radix_tree_delete(&pids, pid);
72
73 f2fs_radix_tree_insert(&pids, pid, current);
74
75 trace_printk("%3x:%3x %4x %-16s\n",
76 MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev),
77 pid, current->comm);
78 out:
79 spin_unlock(&pids_lock);
80 radix_tree_preload_end();
81 }
82
f2fs_trace_ios(struct page * page,struct f2fs_io_info * fio,int flush)83 void f2fs_trace_ios(struct page *page, struct f2fs_io_info *fio, int flush)
84 {
85 struct inode *inode;
86 pid_t pid;
87 int major, minor;
88
89 if (flush) {
90 __print_last_io();
91 return;
92 }
93
94 inode = page->mapping->host;
95 pid = page_private(page);
96
97 major = MAJOR(inode->i_sb->s_dev);
98 minor = MINOR(inode->i_sb->s_dev);
99
100 if (last_io.major == major && last_io.minor == minor &&
101 last_io.pid == pid &&
102 last_io.type == __file_type(inode, pid) &&
103 last_io.fio.rw == fio->rw &&
104 last_io.fio.blk_addr + last_io.len == fio->blk_addr) {
105 last_io.len++;
106 return;
107 }
108
109 __print_last_io();
110
111 last_io.major = major;
112 last_io.minor = minor;
113 last_io.pid = pid;
114 last_io.type = __file_type(inode, pid);
115 last_io.fio = *fio;
116 last_io.len = 1;
117 return;
118 }
119
f2fs_build_trace_ios(void)120 void f2fs_build_trace_ios(void)
121 {
122 spin_lock_init(&pids_lock);
123 }
124
125 #define PIDVEC_SIZE 128
gang_lookup_pids(pid_t * results,unsigned long first_index,unsigned int max_items)126 static unsigned int gang_lookup_pids(pid_t *results, unsigned long first_index,
127 unsigned int max_items)
128 {
129 struct radix_tree_iter iter;
130 void **slot;
131 unsigned int ret = 0;
132
133 if (unlikely(!max_items))
134 return 0;
135
136 radix_tree_for_each_slot(slot, &pids, &iter, first_index) {
137 results[ret] = iter.index;
138 if (++ret == PIDVEC_SIZE)
139 break;
140 }
141 return ret;
142 }
143
f2fs_destroy_trace_ios(void)144 void f2fs_destroy_trace_ios(void)
145 {
146 pid_t pid[PIDVEC_SIZE];
147 pid_t next_pid = 0;
148 unsigned int found;
149
150 spin_lock(&pids_lock);
151 while ((found = gang_lookup_pids(pid, next_pid, PIDVEC_SIZE))) {
152 unsigned idx;
153
154 next_pid = pid[found - 1] + 1;
155 for (idx = 0; idx < found; idx++)
156 radix_tree_delete(&pids, pid[idx]);
157 }
158 spin_unlock(&pids_lock);
159 }
160