linux/fs/f2fs/trace.c
Sahitya Tummala 9083977dab f2fs: do not use mutex lock in atomic context
Fix below warning coming because of using mutex lock in atomic context.

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:98
in_atomic(): 1, irqs_disabled(): 0, pid: 585, name: sh
Preemption disabled at: __radix_tree_preload+0x28/0x130
Call trace:
 dump_backtrace+0x0/0x2b4
 show_stack+0x20/0x28
 dump_stack+0xa8/0xe0
 ___might_sleep+0x144/0x194
 __might_sleep+0x58/0x8c
 mutex_lock+0x2c/0x48
 f2fs_trace_pid+0x88/0x14c
 f2fs_set_node_page_dirty+0xd0/0x184

Do not use f2fs_radix_tree_insert() to avoid doing cond_resched() with
spin_lock() acquired.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-03-05 19:58:06 -08:00

166 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* f2fs IO tracer
*
* Copyright (c) 2014 Motorola Mobility
* Copyright (c) 2014 Jaegeuk Kim <jaegeuk@kernel.org>
*/
#include <linux/fs.h>
#include <linux/f2fs_fs.h>
#include <linux/sched.h>
#include <linux/radix-tree.h>
#include "f2fs.h"
#include "trace.h"
static RADIX_TREE(pids, GFP_ATOMIC);
static spinlock_t pids_lock;
static struct last_io_info last_io;
static inline void __print_last_io(void)
{
if (!last_io.len)
return;
trace_printk("%3x:%3x %4x %-16s %2x %5x %5x %12x %4x\n",
last_io.major, last_io.minor,
last_io.pid, "----------------",
last_io.type,
last_io.fio.op, last_io.fio.op_flags,
last_io.fio.new_blkaddr,
last_io.len);
memset(&last_io, 0, sizeof(last_io));
}
static int __file_type(struct inode *inode, pid_t pid)
{
if (f2fs_is_atomic_file(inode))
return __ATOMIC_FILE;
else if (f2fs_is_volatile_file(inode))
return __VOLATILE_FILE;
else if (S_ISDIR(inode->i_mode))
return __DIR_FILE;
else if (inode->i_ino == F2FS_NODE_INO(F2FS_I_SB(inode)))
return __NODE_FILE;
else if (inode->i_ino == F2FS_META_INO(F2FS_I_SB(inode)))
return __META_FILE;
else if (pid)
return __NORMAL_FILE;
else
return __MISC_FILE;
}
void f2fs_trace_pid(struct page *page)
{
struct inode *inode = page->mapping->host;
pid_t pid = task_pid_nr(current);
void *p;
set_page_private(page, (unsigned long)pid);
retry:
if (radix_tree_preload(GFP_NOFS))
return;
spin_lock(&pids_lock);
p = radix_tree_lookup(&pids, pid);
if (p == current)
goto out;
if (p)
radix_tree_delete(&pids, pid);
if (radix_tree_insert(&pids, pid, current)) {
spin_unlock(&pids_lock);
radix_tree_preload_end();
cond_resched();
goto retry;
}
trace_printk("%3x:%3x %4x %-16s\n",
MAJOR(inode->i_sb->s_dev), MINOR(inode->i_sb->s_dev),
pid, current->comm);
out:
spin_unlock(&pids_lock);
radix_tree_preload_end();
}
void f2fs_trace_ios(struct f2fs_io_info *fio, int flush)
{
struct inode *inode;
pid_t pid;
int major, minor;
if (flush) {
__print_last_io();
return;
}
inode = fio->page->mapping->host;
pid = page_private(fio->page);
major = MAJOR(inode->i_sb->s_dev);
minor = MINOR(inode->i_sb->s_dev);
if (last_io.major == major && last_io.minor == minor &&
last_io.pid == pid &&
last_io.type == __file_type(inode, pid) &&
last_io.fio.op == fio->op &&
last_io.fio.op_flags == fio->op_flags &&
last_io.fio.new_blkaddr + last_io.len ==
fio->new_blkaddr) {
last_io.len++;
return;
}
__print_last_io();
last_io.major = major;
last_io.minor = minor;
last_io.pid = pid;
last_io.type = __file_type(inode, pid);
last_io.fio = *fio;
last_io.len = 1;
return;
}
void f2fs_build_trace_ios(void)
{
spin_lock_init(&pids_lock);
}
#define PIDVEC_SIZE 128
static unsigned int gang_lookup_pids(pid_t *results, unsigned long first_index,
unsigned int max_items)
{
struct radix_tree_iter iter;
void **slot;
unsigned int ret = 0;
if (unlikely(!max_items))
return 0;
radix_tree_for_each_slot(slot, &pids, &iter, first_index) {
results[ret] = iter.index;
if (++ret == max_items)
break;
}
return ret;
}
void f2fs_destroy_trace_ios(void)
{
pid_t pid[PIDVEC_SIZE];
pid_t next_pid = 0;
unsigned int found;
spin_lock(&pids_lock);
while ((found = gang_lookup_pids(pid, next_pid, PIDVEC_SIZE))) {
unsigned idx;
next_pid = pid[found - 1] + 1;
for (idx = 0; idx < found; idx++)
radix_tree_delete(&pids, pid[idx]);
}
spin_unlock(&pids_lock);
}