GNU Linux-libre 4.9.308-gnu1
[releases.git] / fs / f2fs / trace.c
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
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
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
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         page->private = 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
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
129 void f2fs_build_trace_ios(void)
130 {
131         spin_lock_init(&pids_lock);
132 }
133
134 #define PIDVEC_SIZE     128
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 == PIDVEC_SIZE)
148                         break;
149         }
150         return ret;
151 }
152
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 }