btrfs-progs/utils.h
Anand Jain 2f55fd7019 btrfs-progs: optimize btrfs_scan_lblkid() for multiple calls
btrfs_scan_lblikd() is called by most the device related command functions.
And btrfs_scan_lblkid() is most expensive function and it becomes more expensive
as number of devices in the system increase. Further some threads call this
function more than once for absolutely no extra benefit and the real waste of
resources. Below list of threads and number of times btrfs_scan_lblkid()
is called in that thread.

  btrfs-find-root            1
  btrfs rescue super-recover 2
  btrfs-debug-tree           1
  btrfs-image -r             2
  btrfs check                2
  btrfs restore              2
  calc-size                  NC
  btrfs-corrupt-block        NC
  btrfs-image                NC
  btrfs-map-logical          1
  btrfs-select-super         NC
  btrfstune                  2
  btrfs-zero-log             NC
  tester                     NC
  quick-test.c               NC
  btrfs-convert              0
  mkfs                       #number of devices to be mkfs
  btrfs label set unmounted  2
  btrfs get label unmounted  2

This patch will:
  move out calling register_one_device with in btrfs_scan_lblkid()
  and so function setting the BTRFS_UPDATE_KERNEL to yes will
  call btrfs_register_all_devices() separately.

  introduce a global variable scan_done, which is set when scan is
  done succssfully per thread. So that following calls to this function
  will just return success.

  Further if any function needs to force scan after scan_done is set,
  then it can be done when there is such a requirement, but as of now there
  isn't any such requirement.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-11-03 19:17:11 +01:00

165 lines
5.9 KiB
C

/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef __UTILS__
#define __UTILS__
#include <sys/stat.h>
#include "ctree.h"
#include <dirent.h>
#define BTRFS_MKFS_SYSTEM_GROUP_SIZE (4 * 1024 * 1024)
#define BTRFS_MKFS_SMALL_VOLUME_SIZE (1024 * 1024 * 1024)
#define BTRFS_SCAN_MOUNTED (1ULL << 0)
#define BTRFS_SCAN_LBLKID (1ULL << 1)
#define BTRFS_UPDATE_KERNEL 1
#define BTRFS_ARG_UNKNOWN 0
#define BTRFS_ARG_MNTPOINT 1
#define BTRFS_ARG_UUID 2
#define BTRFS_ARG_BLKDEV 3
#define BTRFS_UUID_UNPARSED_SIZE 37
#define ARGV0_BUF_SIZE 64
int check_argc_exact(int nargs, int expected);
int check_argc_min(int nargs, int expected);
int check_argc_max(int nargs, int expected);
void fixup_argv0(char **argv, const char *token);
void set_argv0(char **argv);
/*
* Output modes of size
*/
#define UNITS_RESERVED (0)
#define UNITS_BYTES (1)
#define UNITS_KBYTES (2)
#define UNITS_MBYTES (3)
#define UNITS_GBYTES (4)
#define UNITS_TBYTES (5)
#define UNITS_RAW (1U << UNITS_MODE_SHIFT)
#define UNITS_BINARY (2U << UNITS_MODE_SHIFT)
#define UNITS_DECIMAL (3U << UNITS_MODE_SHIFT)
#define UNITS_MODE_MASK ((1U << UNITS_MODE_SHIFT) - 1)
#define UNITS_MODE_SHIFT (8)
#define UNITS_HUMAN_BINARY (UNITS_BINARY)
#define UNITS_HUMAN_DECIMAL (UNITS_DECIMAL)
#define UNITS_HUMAN (UNITS_HUMAN_BINARY)
#define UNITS_DEFAULT (UNITS_HUMAN)
void units_set_mode(unsigned *units, unsigned mode);
void units_set_base(unsigned *units, unsigned base);
int make_btrfs(int fd, const char *device, const char *label,
char *fs_uuid, u64 blocks[6], u64 num_bytes, u32 nodesize,
u32 leafsize, u32 sectorsize, u32 stripesize, u64 features);
int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 objectid);
int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret,
u64 max_block_count, int *mixed, int discard);
int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int fd, char *path,
u64 block_count, u32 io_width, u32 io_align,
u32 sectorsize);
int btrfs_scan_for_fsid(int run_ioctls);
int btrfs_register_one_device(const char *fname);
int btrfs_register_all_devices(void);
char *canonicalize_dm_name(const char *ptname);
char *canonicalize_path(const char *path);
int check_mounted(const char *devicename);
int check_mounted_where(int fd, const char *file, char *where, int size,
struct btrfs_fs_devices **fs_devices_mnt);
int btrfs_device_already_in_root(struct btrfs_root *root, int fd,
int super_offset);
int pretty_size_snprintf(u64 size, char *str, size_t str_bytes, unsigned unit_mode);
#define pretty_size(size) pretty_size_mode(size, UNITS_DEFAULT)
#define pretty_size_mode(size, mode) \
({ \
static __thread char _str[32]; \
(void)pretty_size_snprintf((size), _str, sizeof(_str), (mode)); \
_str; \
})
int get_mountpt(char *dev, char *mntpt, size_t size);
int btrfs_scan_block_devices(int run_ioctl);
u64 parse_size(char *s);
u64 arg_strtou64(const char *str);
int open_file_or_dir(const char *fname, DIR **dirstream);
int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags);
void close_file_or_dir(int fd, DIR *dirstream);
int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args,
struct btrfs_ioctl_dev_info_args **di_ret);
int get_label(const char *btrfs_dev, char *label);
int set_label(const char *btrfs_dev, const char *label);
char *__strncpy__null(char *dest, const char *src, size_t n);
int is_block_device(const char *file);
int is_mount_point(const char *file);
int open_path_or_dev_mnt(const char *path, DIR **dirstream);
u64 btrfs_device_size(int fd, struct stat *st);
/* Helper to always get proper size of the destination string */
#define strncpy_null(dest, src) __strncpy__null(dest, src, sizeof(dest))
int test_dev_for_mkfs(char *file, int force_overwrite, char *estr);
int get_label_mounted(const char *mount_path, char *labelp);
int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
u64 dev_cnt, int mixed, char *estr);
int is_vol_small(char *file);
int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
int verify);
int ask_user(char *question);
int lookup_ino_rootid(int fd, u64 *rootid);
int btrfs_scan_lblkid(void);
int get_btrfs_mount(const char *dev, char *mp, size_t mp_size);
int find_mount_root(const char *path, char **mount_root);
int get_device_info(int fd, u64 devid,
struct btrfs_ioctl_dev_info_args *di_args);
int test_uuid_unique(char *fs_uuid);
int test_minimum_size(const char *file, u32 leafsize);
int test_issubvolname(const char *name);
int test_isdir(const char *path);
/*
* Btrfs minimum size calculation is complicated, it should include at least:
* 1. system group size
* 2. minimum global block reserve
* 3. metadata used at mkfs
* 4. space reservation to create uuid for first mount.
* Also, raid factor should also be taken into consideration.
* To avoid the overkill calculation, (system group + global block rsv) * 2
* for *EACH* device should be good enough.
*/
static inline u64 btrfs_min_global_blk_rsv_size(u32 leafsize)
{
return leafsize << 10;
}
static inline u64 btrfs_min_dev_size(u32 leafsize)
{
return 2 * (BTRFS_MKFS_SYSTEM_GROUP_SIZE +
btrfs_min_global_blk_rsv_size(leafsize));
}
int find_next_key(struct btrfs_path *path, struct btrfs_key *key);
#endif