1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * f2fs IO tracer
  4 *
  5 * Copyright (c) 2014 Motorola Mobility
  6 * Copyright (c) 2014 Jaegeuk Kim <jaegeuk@kernel.org>
  7 */
  8#include <linux/fs.h>
  9#include <linux/f2fs_fs.h>
 10#include <linux/sched.h>
 11#include <linux/radix-tree.h>
 12
 13#include "f2fs.h"
 14#include "trace.h"
 15
 16static RADIX_TREE(pids, GFP_ATOMIC);
 17static spinlock_t pids_lock;
 18static struct last_io_info last_io;
 19
 20static inline void __print_last_io(void)
 21{
 22	if (!last_io.len)
 23		return;
 24
 25	trace_printk("%3x:%3x %4x %-16s %2x %5x %5x %12x %4x\n",
 26			last_io.major, last_io.minor,
 27			last_io.pid, "----------------",
 28			last_io.type,
 29			last_io.fio.op, last_io.fio.op_flags,
 30			last_io.fio.new_blkaddr,
 31			last_io.len);
 32	memset(&last_io, 0, sizeof(last_io));
 33}
 34
 35static int __file_type(struct inode *inode, pid_t pid)
 36{
 37	if (f2fs_is_atomic_file(inode))
 38		return __ATOMIC_FILE;
 39	else if (f2fs_is_volatile_file(inode))
 40		return __VOLATILE_FILE;
 41	else if (S_ISDIR(inode->i_mode))
 42		return __DIR_FILE;
 43	else if (inode->i_ino == F2FS_NODE_INO(F2FS_I_SB(inode)))
 44		return __NODE_FILE;
 45	else if (inode->i_ino == F2FS_META_INO(F2FS_I_SB(inode)))
 46		return __META_FILE;
 47	else if (pid)
 48		return __NORMAL_FILE;
 49	else
 50		return __MISC_FILE;
 51}
 52
 53void f2fs_trace_pid(struct page *page)
 54{
 55	struct inode *inode = page->mapping->host;
 56	pid_t pid = task_pid_nr(current);
 57	void *p;
 58
 59	set_page_private(page, (unsigned long)pid);
 60
 61retry:
 62	if (radix_tree_preload(GFP_NOFS))
 63		return;
 64
 65	spin_lock(&pids_lock);
 66	p = radix_tree_lookup(&pids, pid);
 67	if (p == current)
 68		goto out;
 69	if (p)
 70		radix_tree_delete(&pids, pid);
 71
 72	if (radix_tree_insert(&pids, pid, current)) {
 73		spin_unlock(&pids_lock);
 74		radix_tree_preload_end();
 75		cond_resched();
 76		goto retry;
 77	}
 78
 79	trace_printk("%3x:%3x %4x %-16s\n",
 80			MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev),
 81			pid, current->comm);
 82out:
 83	spin_unlock(&pids_lock);
 84	radix_tree_preload_end();
 85}
 86
 87void f2fs_trace_ios(struct f2fs_io_info *fio, int flush)
 88{
 89	struct inode *inode;
 90	pid_t pid;
 91	int major, minor;
 92
 93	if (flush) {
 94		__print_last_io();
 95		return;
 96	}
 97
 98	inode = fio->page->mapping->host;
 99	pid = page_private(fio->page);
100
101	major = MAJOR(inode->i_sb->s_dev);
102	minor = MINOR(inode->i_sb->s_dev);
103
104	if (last_io.major == major && last_io.minor == minor &&
105			last_io.pid == pid &&
106			last_io.type == __file_type(inode, pid) &&
107			last_io.fio.op == fio->op &&
108			last_io.fio.op_flags == fio->op_flags &&
109			last_io.fio.new_blkaddr + last_io.len ==
110							fio->new_blkaddr) {
111		last_io.len++;
112		return;
113	}
114
115	__print_last_io();
116
117	last_io.major = major;
118	last_io.minor = minor;
119	last_io.pid = pid;
120	last_io.type = __file_type(inode, pid);
121	last_io.fio = *fio;
122	last_io.len = 1;
123	return;
124}
125
126void f2fs_build_trace_ios(void)
127{
128	spin_lock_init(&pids_lock);
129}
130
131#define PIDVEC_SIZE	128
132static unsigned int gang_lookup_pids(pid_t *results, unsigned long first_index,
133							unsigned int max_items)
134{
135	struct radix_tree_iter iter;
136	void **slot;
137	unsigned int ret = 0;
138
139	if (unlikely(!max_items))
140		return 0;
141
142	radix_tree_for_each_slot(slot, &pids, &iter, first_index) {
143		results[ret] = iter.index;
144		if (++ret == max_items)
145			break;
146	}
147	return ret;
148}
149
150void f2fs_destroy_trace_ios(void)
151{
152	pid_t pid[PIDVEC_SIZE];
153	pid_t next_pid = 0;
154	unsigned int found;
155
156	spin_lock(&pids_lock);
157	while ((found = gang_lookup_pids(pid, next_pid, PIDVEC_SIZE))) {
158		unsigned idx;
159
160		next_pid = pid[found - 1] + 1;
161		for (idx = 0; idx < found; idx++)
162			radix_tree_delete(&pids, pid[idx]);
163	}
164	spin_unlock(&pids_lock);
165}