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 %5x %12x %4x\n",
29 last_io.major, last_io.minor,
30 last_io.pid, "----------------",
31 last_io.type,
32 last_io.fio.op, last_io.fio.op_flags,
33 last_io.fio.new_blkaddr,
34 last_io.len);
35 memset(&last_io, 0, sizeof(last_io));
36 }
37
__file_type(struct inode * inode,pid_t pid)38 static int __file_type(struct inode *inode, pid_t pid)
39 {
40 if (f2fs_is_atomic_file(inode))
41 return __ATOMIC_FILE;
42 else if (f2fs_is_volatile_file(inode))
43 return __VOLATILE_FILE;
44 else if (S_ISDIR(inode->i_mode))
45 return __DIR_FILE;
46 else if (inode->i_ino == F2FS_NODE_INO(F2FS_I_SB(inode)))
47 return __NODE_FILE;
48 else if (inode->i_ino == F2FS_META_INO(F2FS_I_SB(inode)))
49 return __META_FILE;
50 else if (pid)
51 return __NORMAL_FILE;
52 else
53 return __MISC_FILE;
54 }
55
f2fs_trace_pid(struct page * page)56 void f2fs_trace_pid(struct page *page)
57 {
58 struct inode *inode = page->mapping->host;
59 pid_t pid = task_pid_nr(current);
60 void *p;
61
62 set_page_private(page, (unsigned long)pid);
63
64 retry:
65 if (radix_tree_preload(GFP_NOFS))
66 return;
67
68 spin_lock(&pids_lock);
69 p = radix_tree_lookup(&pids, pid);
70 if (p == current)
71 goto out;
72 if (p)
73 radix_tree_delete(&pids, pid);
74
75 if (radix_tree_insert(&pids, pid, current)) {
76 spin_unlock(&pids_lock);
77 radix_tree_preload_end();
78 cond_resched();
79 goto retry;
80 }
81
82 trace_printk("%3x:%3x %4x %-16s\n",
83 MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev),
84 pid, current->comm);
85 out:
86 spin_unlock(&pids_lock);
87 radix_tree_preload_end();
88 }
89
f2fs_trace_ios(struct f2fs_io_info * fio,int flush)90 void f2fs_trace_ios(struct f2fs_io_info *fio, int flush)
91 {
92 struct inode *inode;
93 pid_t pid;
94 int major, minor;
95
96 if (flush) {
97 __print_last_io();
98 return;
99 }
100
101 inode = fio->page->mapping->host;
102 pid = page_private(fio->page);
103
104 major = MAJOR(inode->i_sb->s_dev);
105 minor = MINOR(inode->i_sb->s_dev);
106
107 if (last_io.major == major && last_io.minor == minor &&
108 last_io.pid == pid &&
109 last_io.type == __file_type(inode, pid) &&
110 last_io.fio.op == fio->op &&
111 last_io.fio.op_flags == fio->op_flags &&
112 last_io.fio.new_blkaddr + last_io.len ==
113 fio->new_blkaddr) {
114 last_io.len++;
115 return;
116 }
117
118 __print_last_io();
119
120 last_io.major = major;
121 last_io.minor = minor;
122 last_io.pid = pid;
123 last_io.type = __file_type(inode, pid);
124 last_io.fio = *fio;
125 last_io.len = 1;
126 return;
127 }
128
f2fs_build_trace_ios(void)129 void f2fs_build_trace_ios(void)
130 {
131 spin_lock_init(&pids_lock);
132 }
133
134 #define PIDVEC_SIZE 128
gang_lookup_pids(pid_t * results,unsigned long first_index,unsigned int max_items)135 static unsigned int gang_lookup_pids(pid_t *results, unsigned long first_index,
136 unsigned int max_items)
137 {
138 struct radix_tree_iter iter;
139 void **slot;
140 unsigned int ret = 0;
141
142 if (unlikely(!max_items))
143 return 0;
144
145 radix_tree_for_each_slot(slot, &pids, &iter, first_index) {
146 results[ret] = iter.index;
147 if (++ret == max_items)
148 break;
149 }
150 return ret;
151 }
152
f2fs_destroy_trace_ios(void)153 void f2fs_destroy_trace_ios(void)
154 {
155 pid_t pid[PIDVEC_SIZE];
156 pid_t next_pid = 0;
157 unsigned int found;
158
159 spin_lock(&pids_lock);
160 while ((found = gang_lookup_pids(pid, next_pid, PIDVEC_SIZE))) {
161 unsigned idx;
162
163 next_pid = pid[found - 1] + 1;
164 for (idx = 0; idx < found; idx++)
165 radix_tree_delete(&pids, pid[idx]);
166 }
167 spin_unlock(&pids_lock);
168 }
169