linux/fs/btrfs/tests/btrfs-tests.c
Nikolay Borisov 46cc775e29 btrfs: Adjust loop in free_extent_buffer
The loop construct in free_extent_buffer was added in
242e18c7c1 ("Btrfs: reduce lock contention on extent buffer locks")
as means of reducing the times the eb lock is taken, the non-last ref
count is decremented and lock is released. As the special handling
of UNMAPPED extent buffers was removed now there is only one decrement
op which is happening for EXTENT_BUFFER_UNMAPPED case.

This commit modifies the loop condition so that in case of UNMAPPED
buffers the eb's lock is taken only if we are 100% sure the eb is going
to be freed by the current executor of the code. Additionally, remove
superfluous ref count ops in btrfs test.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00

277 lines
6.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2013 Fusion IO. All rights reserved.
*/
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/magic.h>
#include "btrfs-tests.h"
#include "../ctree.h"
#include "../free-space-cache.h"
#include "../free-space-tree.h"
#include "../transaction.h"
#include "../volumes.h"
#include "../disk-io.h"
#include "../qgroup.h"
static struct vfsmount *test_mnt = NULL;
static const struct super_operations btrfs_test_super_ops = {
.alloc_inode = btrfs_alloc_inode,
.destroy_inode = btrfs_test_destroy_inode,
};
static struct dentry *btrfs_test_mount(struct file_system_type *fs_type,
int flags, const char *dev_name,
void *data)
{
return mount_pseudo(fs_type, "btrfs_test:", &btrfs_test_super_ops,
NULL, BTRFS_TEST_MAGIC);
}
static struct file_system_type test_type = {
.name = "btrfs_test_fs",
.mount = btrfs_test_mount,
.kill_sb = kill_anon_super,
};
struct inode *btrfs_new_test_inode(void)
{
return new_inode(test_mnt->mnt_sb);
}
static int btrfs_init_test_fs(void)
{
int ret;
ret = register_filesystem(&test_type);
if (ret) {
printk(KERN_ERR "btrfs: cannot register test file system\n");
return ret;
}
test_mnt = kern_mount(&test_type);
if (IS_ERR(test_mnt)) {
printk(KERN_ERR "btrfs: cannot mount test file system\n");
unregister_filesystem(&test_type);
return PTR_ERR(test_mnt);
}
return 0;
}
static void btrfs_destroy_test_fs(void)
{
kern_unmount(test_mnt);
unregister_filesystem(&test_type);
}
struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(u32 nodesize, u32 sectorsize)
{
struct btrfs_fs_info *fs_info = kzalloc(sizeof(struct btrfs_fs_info),
GFP_KERNEL);
if (!fs_info)
return fs_info;
fs_info->fs_devices = kzalloc(sizeof(struct btrfs_fs_devices),
GFP_KERNEL);
if (!fs_info->fs_devices) {
kfree(fs_info);
return NULL;
}
fs_info->super_copy = kzalloc(sizeof(struct btrfs_super_block),
GFP_KERNEL);
if (!fs_info->super_copy) {
kfree(fs_info->fs_devices);
kfree(fs_info);
return NULL;
}
fs_info->nodesize = nodesize;
fs_info->sectorsize = sectorsize;
if (init_srcu_struct(&fs_info->subvol_srcu)) {
kfree(fs_info->fs_devices);
kfree(fs_info->super_copy);
kfree(fs_info);
return NULL;
}
spin_lock_init(&fs_info->buffer_lock);
spin_lock_init(&fs_info->qgroup_lock);
spin_lock_init(&fs_info->qgroup_op_lock);
spin_lock_init(&fs_info->super_lock);
spin_lock_init(&fs_info->fs_roots_radix_lock);
spin_lock_init(&fs_info->tree_mod_seq_lock);
mutex_init(&fs_info->qgroup_ioctl_lock);
mutex_init(&fs_info->qgroup_rescan_lock);
rwlock_init(&fs_info->tree_mod_log_lock);
fs_info->running_transaction = NULL;
fs_info->qgroup_tree = RB_ROOT;
fs_info->qgroup_ulist = NULL;
atomic64_set(&fs_info->tree_mod_seq, 0);
INIT_LIST_HEAD(&fs_info->dirty_qgroups);
INIT_LIST_HEAD(&fs_info->dead_roots);
INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
extent_io_tree_init(&fs_info->freed_extents[0], NULL);
extent_io_tree_init(&fs_info->freed_extents[1], NULL);
fs_info->pinned_extents = &fs_info->freed_extents[0];
set_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
test_mnt->mnt_sb->s_fs_info = fs_info;
return fs_info;
}
void btrfs_free_dummy_fs_info(struct btrfs_fs_info *fs_info)
{
struct radix_tree_iter iter;
void **slot;
if (!fs_info)
return;
if (WARN_ON(!test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO,
&fs_info->fs_state)))
return;
test_mnt->mnt_sb->s_fs_info = NULL;
spin_lock(&fs_info->buffer_lock);
radix_tree_for_each_slot(slot, &fs_info->buffer_radix, &iter, 0) {
struct extent_buffer *eb;
eb = radix_tree_deref_slot_protected(slot, &fs_info->buffer_lock);
if (!eb)
continue;
/* Shouldn't happen but that kind of thinking creates CVE's */
if (radix_tree_exception(eb)) {
if (radix_tree_deref_retry(eb))
slot = radix_tree_iter_retry(&iter);
continue;
}
slot = radix_tree_iter_resume(slot, &iter);
spin_unlock(&fs_info->buffer_lock);
free_extent_buffer_stale(eb);
spin_lock(&fs_info->buffer_lock);
}
spin_unlock(&fs_info->buffer_lock);
btrfs_free_qgroup_config(fs_info);
btrfs_free_fs_roots(fs_info);
cleanup_srcu_struct(&fs_info->subvol_srcu);
kfree(fs_info->super_copy);
kfree(fs_info->fs_devices);
kfree(fs_info);
}
void btrfs_free_dummy_root(struct btrfs_root *root)
{
if (!root)
return;
/* Will be freed by btrfs_free_fs_roots */
if (WARN_ON(test_bit(BTRFS_ROOT_IN_RADIX, &root->state)))
return;
if (root->node) {
/* One for allocate_extent_buffer */
free_extent_buffer(root->node);
}
kfree(root);
}
struct btrfs_block_group_cache *
btrfs_alloc_dummy_block_group(struct btrfs_fs_info *fs_info,
unsigned long length)
{
struct btrfs_block_group_cache *cache;
cache = kzalloc(sizeof(*cache), GFP_KERNEL);
if (!cache)
return NULL;
cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
GFP_KERNEL);
if (!cache->free_space_ctl) {
kfree(cache);
return NULL;
}
cache->key.objectid = 0;
cache->key.offset = length;
cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
cache->full_stripe_len = fs_info->sectorsize;
cache->fs_info = fs_info;
INIT_LIST_HEAD(&cache->list);
INIT_LIST_HEAD(&cache->cluster_list);
INIT_LIST_HEAD(&cache->bg_list);
btrfs_init_free_space_ctl(cache);
mutex_init(&cache->free_space_lock);
return cache;
}
void btrfs_free_dummy_block_group(struct btrfs_block_group_cache *cache)
{
if (!cache)
return;
__btrfs_remove_free_space_cache(cache->free_space_ctl);
kfree(cache->free_space_ctl);
kfree(cache);
}
void btrfs_init_dummy_trans(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
memset(trans, 0, sizeof(*trans));
trans->transid = 1;
trans->type = __TRANS_DUMMY;
trans->fs_info = fs_info;
}
int btrfs_run_sanity_tests(void)
{
int ret, i;
u32 sectorsize, nodesize;
u32 test_sectorsize[] = {
PAGE_SIZE,
};
ret = btrfs_init_test_fs();
if (ret)
return ret;
for (i = 0; i < ARRAY_SIZE(test_sectorsize); i++) {
sectorsize = test_sectorsize[i];
for (nodesize = sectorsize;
nodesize <= BTRFS_MAX_METADATA_BLOCKSIZE;
nodesize <<= 1) {
pr_info("BTRFS: selftest: sectorsize: %u nodesize: %u\n",
sectorsize, nodesize);
ret = btrfs_test_free_space_cache(sectorsize, nodesize);
if (ret)
goto out;
ret = btrfs_test_extent_buffer_operations(sectorsize,
nodesize);
if (ret)
goto out;
ret = btrfs_test_extent_io(sectorsize, nodesize);
if (ret)
goto out;
ret = btrfs_test_inodes(sectorsize, nodesize);
if (ret)
goto out;
ret = btrfs_test_qgroups(sectorsize, nodesize);
if (ret)
goto out;
ret = btrfs_test_free_space_tree(sectorsize, nodesize);
if (ret)
goto out;
}
}
ret = btrfs_test_extent_map();
out:
btrfs_destroy_test_fs();
return ret;
}