Commit Graph

1760 Commits

Author SHA1 Message Date
Chao Yu
7041d5d286 f2fs: combine nat_bits and free_nid_bitmap cache
Both nat_bits cache and free_nid_bitmap cache provide same functionality
as a intermediate cache between free nid cache and disk, but with
different granularity of indicating free nid range, and different
persistence policy. nat_bits cache provides better persistence ability,
and free_nid_bitmap provides better granularity.

In this patch we combine advantage of both caches, so finally policy of
the intermediate cache would be:
- init: load free nid status from nat_bits into free_nid_bitmap
- lookup: scan free_nid_bitmap before load NAT blocks
- update: update free_nid_bitmap in real-time
- persistence: udpate and persist nat_bits in checkpoint

This patch also resolves performance regression reported by lkp-robot.

commit:
  4ac912427c ("f2fs: introduce free nid bitmap")
  d00030cf9cd0bb96fdccc41e33d3c91dcbb672ba ("f2fs: use __set{__clear}_bit_le")
  1382c0f3f9d3f936c8bc42ed1591cf7a593ef9f7 ("f2fs: combine nat_bits and free_nid_bitmap cache")

4ac912427c d00030cf9cd0bb96fdccc41e33 1382c0f3f9d3f936c8bc42ed15
---------------- -------------------------- --------------------------
         %stddev     %change         %stddev     %change         %stddev
             \          |                \          |                \
     77863 ±  0%      +2.1%      79485 ±  1%     +50.8%     117404 ±  0%  aim7.jobs-per-min
    231.63 ±  0%      -2.0%     227.01 ±  1%     -33.6%     153.80 ±  0%  aim7.time.elapsed_time
    231.63 ±  0%      -2.0%     227.01 ±  1%     -33.6%     153.80 ±  0%  aim7.time.elapsed_time.max
    896604 ±  0%      -0.8%     889221 ±  3%     -20.2%     715260 ±  1%  aim7.time.involuntary_context_switches
      2394 ±  1%      +4.6%       2503 ±  1%      +3.7%       2481 ±  2%  aim7.time.maximum_resident_set_size
      6240 ±  0%      -1.5%       6145 ±  1%     -14.1%       5360 ±  1%  aim7.time.system_time
   1111357 ±  3%      +1.9%    1132509 ±  2%      -6.2%    1041932 ±  2%  aim7.time.voluntary_context_switches
...

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Tested-by: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-20 10:00:18 -04:00
Chao Yu
586d1492f3 f2fs: skip scanning free nid bitmap of full NAT blocks
This patch adds to account free nids for each NAT blocks, and while
scanning all free nid bitmap, do check count and skip lookuping in
full NAT block.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-20 10:00:17 -04:00
Jaegeuk Kim
23380b8568 f2fs: use __set{__clear}_bit_le
This patch uses __set{__clear}_bit_le for highter speed.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-20 10:00:16 -04:00
Jaegeuk Kim
9f7e4a2c49 f2fs: declare static functions
This is to avoid build warning reported by kbuild test robot.

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-20 10:00:15 -04:00
Jaegeuk Kim
720037f939 f2fs: don't overwrite node block by SSR
This patch fixes that SSR can overwrite previous warm node block consisting of
a node chain since the last checkpoint.

Fixes: 5b6c6be2d8 ("f2fs: use SSR for warm node as well")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-03-20 10:00:14 -04:00
Linus Torvalds
590dce2d49 Merge branch 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs 'statx()' update from Al Viro.

This adds the new extended stat() interface that internally subsumes our
previous stat interfaces, and allows user mode to specify in more detail
what kind of information it wants.

It also allows for some explicit synchronization information to be
passed to the filesystem, which can be relevant for network filesystems:
is the cached value ok, or do you need open/close consistency, or what?

From David Howells.

Andreas Dilger points out that the first version of the extended statx
interface was posted June 29, 2010:

    https://www.spinics.net/lists/linux-fsdevel/msg33831.html

* 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  statx: Add a system call to make enhanced file info available
2017-03-03 11:38:56 -08:00
David Howells
a528d35e8b statx: Add a system call to make enhanced file info available
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.

The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode.  This change is propagated to the vfs_getattr*()
function.

Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.

========
OVERVIEW
========

The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.

A number of requests were gathered for features to be included.  The
following have been included:

 (1) Make the fields a consistent size on all arches and make them large.

 (2) Spare space, request flags and information flags are provided for
     future expansion.

 (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
     __s64).

 (4) Creation time: The SMB protocol carries the creation time, which could
     be exported by Samba, which will in turn help CIFS make use of
     FS-Cache as that can be used for coherency data (stx_btime).

     This is also specified in NFSv4 as a recommended attribute and could
     be exported by NFSD [Steve French].

 (5) Lightweight stat: Ask for just those details of interest, and allow a
     netfs (such as NFS) to approximate anything not of interest, possibly
     without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
     Dilger] (AT_STATX_DONT_SYNC).

 (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
     its cached attributes are up to date [Trond Myklebust]
     (AT_STATX_FORCE_SYNC).

And the following have been left out for future extension:

 (7) Data version number: Could be used by userspace NFS servers [Aneesh
     Kumar].

     Can also be used to modify fill_post_wcc() in NFSD which retrieves
     i_version directly, but has just called vfs_getattr().  It could get
     it from the kstat struct if it used vfs_xgetattr() instead.

     (There's disagreement on the exact semantics of a single field, since
     not all filesystems do this the same way).

 (8) BSD stat compatibility: Including more fields from the BSD stat such
     as creation time (st_btime) and inode generation number (st_gen)
     [Jeremy Allison, Bernd Schubert].

 (9) Inode generation number: Useful for FUSE and userspace NFS servers
     [Bernd Schubert].

     (This was asked for but later deemed unnecessary with the
     open-by-handle capability available and caused disagreement as to
     whether it's a security hole or not).

(10) Extra coherency data may be useful in making backups [Andreas Dilger].

     (No particular data were offered, but things like last backup
     timestamp, the data version number and the DOS archive bit would come
     into this category).

(11) Allow the filesystem to indicate what it can/cannot provide: A
     filesystem can now say it doesn't support a standard stat feature if
     that isn't available, so if, for instance, inode numbers or UIDs don't
     exist or are fabricated locally...

     (This requires a separate system call - I have an fsinfo() call idea
     for this).

(12) Store a 16-byte volume ID in the superblock that can be returned in
     struct xstat [Steve French].

     (Deferred to fsinfo).

(13) Include granularity fields in the time data to indicate the
     granularity of each of the times (NFSv4 time_delta) [Steve French].

     (Deferred to fsinfo).

(14) FS_IOC_GETFLAGS value.  These could be translated to BSD's st_flags.
     Note that the Linux IOC flags are a mess and filesystems such as Ext4
     define flags that aren't in linux/fs.h, so translation in the kernel
     may be a necessity (or, possibly, we provide the filesystem type too).

     (Some attributes are made available in stx_attributes, but the general
     feeling was that the IOC flags were to ext[234]-specific and shouldn't
     be exposed through statx this way).

(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
     Michael Kerrisk].

     (Deferred, probably to fsinfo.  Finding out if there's an ACL or
     seclabal might require extra filesystem operations).

(16) Femtosecond-resolution timestamps [Dave Chinner].

     (A __reserved field has been left in the statx_timestamp struct for
     this - if there proves to be a need).

(17) A set multiple attributes syscall to go with this.

===============
NEW SYSTEM CALL
===============

The new system call is:

	int ret = statx(int dfd,
			const char *filename,
			unsigned int flags,
			unsigned int mask,
			struct statx *buffer);

The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat().  There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags.  There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.

Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):

 (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
     respect.

 (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
     its attributes with the server - which might require data writeback to
     occur to get the timestamps correct.

 (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
     network filesystem.  The resulting values should be considered
     approximate.

mask is a bitmask indicating the fields in struct statx that are of
interest to the caller.  The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat().  It should be noted that asking for
more information may entail extra I/O operations.

buffer points to the destination for the data.  This must be 256 bytes in
size.

======================
MAIN ATTRIBUTES RECORD
======================

The following structures are defined in which to return the main attribute
set:

	struct statx_timestamp {
		__s64	tv_sec;
		__s32	tv_nsec;
		__s32	__reserved;
	};

	struct statx {
		__u32	stx_mask;
		__u32	stx_blksize;
		__u64	stx_attributes;
		__u32	stx_nlink;
		__u32	stx_uid;
		__u32	stx_gid;
		__u16	stx_mode;
		__u16	__spare0[1];
		__u64	stx_ino;
		__u64	stx_size;
		__u64	stx_blocks;
		__u64	__spare1[1];
		struct statx_timestamp	stx_atime;
		struct statx_timestamp	stx_btime;
		struct statx_timestamp	stx_ctime;
		struct statx_timestamp	stx_mtime;
		__u32	stx_rdev_major;
		__u32	stx_rdev_minor;
		__u32	stx_dev_major;
		__u32	stx_dev_minor;
		__u64	__spare2[14];
	};

The defined bits in request_mask and stx_mask are:

	STATX_TYPE		Want/got stx_mode & S_IFMT
	STATX_MODE		Want/got stx_mode & ~S_IFMT
	STATX_NLINK		Want/got stx_nlink
	STATX_UID		Want/got stx_uid
	STATX_GID		Want/got stx_gid
	STATX_ATIME		Want/got stx_atime{,_ns}
	STATX_MTIME		Want/got stx_mtime{,_ns}
	STATX_CTIME		Want/got stx_ctime{,_ns}
	STATX_INO		Want/got stx_ino
	STATX_SIZE		Want/got stx_size
	STATX_BLOCKS		Want/got stx_blocks
	STATX_BASIC_STATS	[The stuff in the normal stat struct]
	STATX_BTIME		Want/got stx_btime{,_ns}
	STATX_ALL		[All currently available stuff]

stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.

Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution.  Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.

The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does.  The following
attributes map to FS_*_FL flags and are the same numerical value:

	STATX_ATTR_COMPRESSED		File is compressed by the fs
	STATX_ATTR_IMMUTABLE		File is marked immutable
	STATX_ATTR_APPEND		File is append-only
	STATX_ATTR_NODUMP		File is not to be dumped
	STATX_ATTR_ENCRYPTED		File requires key to decrypt in fs

Within the kernel, the supported flags are listed by:

	KSTAT_ATTR_FS_IOC_FLAGS

[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]

New flags include:

	STATX_ATTR_AUTOMOUNT		Object is an automount trigger

These are for the use of GUI tools that might want to mark files specially,
depending on what they are.

Fields in struct statx come in a number of classes:

 (0) stx_dev_*, stx_blksize.

     These are local system information and are always available.

 (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
     stx_size, stx_blocks.

     These will be returned whether the caller asks for them or not.  The
     corresponding bits in stx_mask will be set to indicate whether they
     actually have valid values.

     If the caller didn't ask for them, then they may be approximated.  For
     example, NFS won't waste any time updating them from the server,
     unless as a byproduct of updating something requested.

     If the values don't actually exist for the underlying object (such as
     UID or GID on a DOS file), then the bit won't be set in the stx_mask,
     even if the caller asked for the value.  In such a case, the returned
     value will be a fabrication.

     Note that there are instances where the type might not be valid, for
     instance Windows reparse points.

 (2) stx_rdev_*.

     This will be set only if stx_mode indicates we're looking at a
     blockdev or a chardev, otherwise will be 0.

 (3) stx_btime.

     Similar to (1), except this will be set to 0 if it doesn't exist.

=======
TESTING
=======

The following test program can be used to test the statx system call:

	samples/statx/test-statx.c

Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.

Here's some example output.  Firstly, an NFS directory that crosses to
another FSID.  Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.

	[root@andromeda ~]# /tmp/test-statx -A /warthog/data
	statx(/warthog/data) = 0
	results=7ff
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:26           Inode: 1703937     Links: 125
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2016-11-24 09:02:12.219699527+0000
	Modify: 2016-11-17 10:44:36.225653653+0000
	Change: 2016-11-17 10:44:36.225653653+0000
	Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)

Secondly, the result of automounting on that directory.

	[root@andromeda ~]# /tmp/test-statx /warthog/data
	statx(/warthog/data) = 0
	results=7ff
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:27           Inode: 2           Links: 125
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2016-11-24 09:02:12.219699527+0000
	Modify: 2016-11-17 10:44:36.225653653+0000
	Change: 2016-11-17 10:44:36.225653653+0000

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-02 20:51:15 -05:00
Ingo Molnar
174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Linus Torvalds
25c4e6c3f0 for-f2fs-4.11
This round introduces several interesting features such as on-disk NAT bitmaps,
 IO alignment, and a discard thread. And it includes a couple of major bug fixes
 as below.
 
 == Enhancement ==
 - introduce on-disk bitmaps to avoid scanning NAT blocks when getting free nids
 - support IO alignment to prepare open-channel SSD integration in future
 - introduce a discard thread to avoid long latency during checkpoint and fstrim
 - use SSR for warm node and enable inline_xattr by default
 - introduce in-memory bitmaps to check FS consistency for debugging
 - improve write_begin by avoiding needless read IO
 
 == Bug fix ==
 - fix broken zone_reset behavior for SMR drive
 - fix wrong victim selection policy during GC
 - fix missing behavior when preparing discard commands
 - fix bugs in atomic write support and fiemap
 - workaround to handle multiple f2fs_add_link calls having same name
 
 And it includes a bunch of clean-up patches as well.
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Merge tag 'for-f2fs-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "This round introduces several interesting features such as on-disk NAT
  bitmaps, IO alignment, and a discard thread. And it includes a couple
  of major bug fixes as below.

  Enhancements:

   - introduce on-disk bitmaps to avoid scanning NAT blocks when getting
     free nids

   - support IO alignment to prepare open-channel SSD integration in
     future

   - introduce a discard thread to avoid long latency during checkpoint
     and fstrim

   - use SSR for warm node and enable inline_xattr by default

   - introduce in-memory bitmaps to check FS consistency for debugging

   - improve write_begin by avoiding needless read IO

  Bug fixes:

   - fix broken zone_reset behavior for SMR drive

   - fix wrong victim selection policy during GC

   - fix missing behavior when preparing discard commands

   - fix bugs in atomic write support and fiemap

   - workaround to handle multiple f2fs_add_link calls having same name

  ... and it includes a bunch of clean-up patches as well"

* tag 'for-f2fs-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (97 commits)
  f2fs: avoid to flush nat journal entries
  f2fs: avoid to issue redundant discard commands
  f2fs: fix a plint compile warning
  f2fs: add f2fs_drop_inode tracepoint
  f2fs: Fix zoned block device support
  f2fs: remove redundant set_page_dirty()
  f2fs: fix to enlarge size of write_io_dummy mempool
  f2fs: fix memory leak of write_io_dummy mempool during umount
  f2fs: fix to update F2FS_{CP_}WB_DATA count correctly
  f2fs: use MAX_FREE_NIDS for the free nids target
  f2fs: introduce free nid bitmap
  f2fs: new helper cur_cp_crc() getting crc in f2fs_checkpoint
  f2fs: update the comment of default nr_pages to skipping
  f2fs: drop the duplicate pval in f2fs_getxattr
  f2fs: Don't update the xattr data that same as the exist
  f2fs: kill __is_extent_same
  f2fs: avoid bggc->fggc when enough free segments are avaliable after cp
  f2fs: select target segment with closer temperature in SSR mode
  f2fs: show simple call stack in fault injection message
  f2fs: no need lock_op in f2fs_write_inline_data
  ...
2017-03-01 15:55:04 -08:00
Jaegeuk Kim
900f736251 f2fs: avoid to flush nat journal entries
This patch adds a missing condition which flushes nat journal entries
unnecessarily introduced by:

    f2fs: add bitmaps for empty or full NAT blocks

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-28 09:57:13 -08:00
Jaegeuk Kim
8b107f5b97 f2fs: avoid to issue redundant discard commands
If segs_per_sec is over 1 like under SMR, previously f2fs issues discard
commands redundantly on the same section, since we didn't move end position
for the previous discard command.

E.g.,

                       start  end
                         |    |
      prefree_bitmap = [01111100111100]

And, after issue discard for this section,
                             end      start
                              |        |
      prefree_bitmap = [01111100111100]

Select this section again by searching from (end + 1),
                             start  end
                                |   |
      prefree_bitmap = [01111100111100]

Fixes: 36abef4e79 ("f2fs: introduce mode=lfs mount option")
Cc: <stable@vger.kernel.org>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 13:44:08 -08:00
Hou Pengyang
37e79cd31c f2fs: fix a plint compile warning
fix such pclint warning:
...
Loss of precision (arg. no. 2) (unsigned long long to unsigned int))

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:51:21 -08:00
Hou Pengyang
b8d96a30b6 f2fs: add f2fs_drop_inode tracepoint
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:51:20 -08:00
Masato Suzuki
7bb3a371d1 f2fs: Fix zoned block device support
The introduction of the multi-device feature partially broke the support
for zoned block devices. In the function f2fs_scan_devices, sbi->devs
allocation and initialization is skipped in the case of a single device
mount. This result in no device information structure being allocated
for the device. This is fine if the device is a regular device, but in
the case of a zoned block device, the device zone type array is not
initialized, which causes the function __f2fs_issue_discard_zone to fail
as get_blkz_type is unable to determine the zone type of a section.

Fix this by always allocating and initializing the sbi->devs device
information array even in the case of a single device if that device is
zoned. For this particular case, make sure to obtain a reference on the
single device so that the call to blkdev_put() in destroy_device_list
operates as expected.

Fixes: 3c62be17d4 ("f2fs: support multiple devices")
Cc: <stable@vger.kernel.org> # v4.10
Signed-off-by: Masato Suzuki <masato.suzuki@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:40:12 -08:00
Yunlei He
4fcf589ad4 f2fs: remove redundant set_page_dirty()
This patch remove redundant set_page_dirty in truncate_blocks

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:40:11 -08:00
Chao Yu
a3ebfe4fd8 f2fs: fix to enlarge size of write_io_dummy mempool
It needs to double cache size of write_io_dummy mempool, otherwise we may
run out of cache in scenraio of Data/Node IOs were issued concurrently.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:40:10 -08:00
Chao Yu
b6895e8f99 f2fs: fix memory leak of write_io_dummy mempool during umount
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:40:09 -08:00
Chao Yu
540faedb00 f2fs: fix to update F2FS_{CP_}WB_DATA count correctly
We should only account F2FS_{CP_}WB_DATA IOs for write path, fix it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:40:08 -08:00
Kinglong Mee
f0cdbfe6ef f2fs: use MAX_FREE_NIDS for the free nids target
F2FS has define MAX_FREE_NIDS for maximum of cached free nids target.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:48 -08:00
Chao Yu
4ac912427c f2fs: introduce free nid bitmap
In scenario of intensively node allocation, free nids will be ran out
soon, then it needs to stop to load free nids by traversing NAT blocks,
in worse case, if NAT blocks does not be cached in memory, it generates
IOs which slows down our foreground operations.

In order to speed up node allocation, in this patch we introduce a new
free_nid_bitmap array, so there is an bitmap table for each NAT block,
Once the NAT block is loaded, related bitmap cache will be switched on,
and bitmap will be set during traversing nat entries in NAT block, later
we can query and update nid usage status in memory completely.

With such implementation, I expect performance of node allocation can be
improved in the long-term after filesystem image is mounted.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:47 -08:00
Kinglong Mee
ced2c7ea8e f2fs: new helper cur_cp_crc() getting crc in f2fs_checkpoint
There are four places that getting the crc value in f2fs_checkpoint,
just add a new helper cur_cp_crc for them.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:47 -08:00
Kinglong Mee
727ebb091e f2fs: update the comment of default nr_pages to skipping
Fixes: 2c237ebaa4 ("f2fs: avoid writing node/metapages during writes")
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:46 -08:00
Kinglong Mee
0ec4a5b647 f2fs: drop the duplicate pval in f2fs_getxattr
Fixes: ba38c27eb9 ("f2fs: enhance lookup xattr")
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:45 -08:00
Kinglong Mee
5f35a2cd5b f2fs: Don't update the xattr data that same as the exist
f2fs removes the old xattr data and appends the new data although
the new data is same as the exist.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:44 -08:00
Chao Yu
317e130096 f2fs: kill __is_extent_same
Since commit ee6d182f2a ("f2fs: remove syncing inode page in all the
cases") delayed inode element updating from inode cache to node page
cache, so once largest cached extent is updated, we can make inode dirty
immediately instead of checking and updating it in the end of extent
cache update.

The above commit didn't clean up unneeded codes in extent_cache.c, let's
finish the job in this patch.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:43 -08:00
Hou Pengyang
19f4e688f8 f2fs: avoid bggc->fggc when enough free segments are avaliable after cp
We use has_not_enough_free_secs to check if there are enough free segments,

    	(free_sections(sbi) + freed) <=
	        (node_secs + 2 * dent_secs + imeta_secs +
			         reserved_sections(sbi) + needed);

Under scenario with large number of dirty nodes, these nodes would be flushed
during cp, as a result, right side of the inequality would be decreased, while
left side stays unchanged if these nodes are flushed in SSR way, which means
there are enough free segments after this cp.

For this case, we just do a bggc instead of fggc.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 10:07:37 -08:00
Chao Yu
d27c3d89db f2fs: select target segment with closer temperature in SSR mode
In SSR mode, we can allocate target segment which has different
temperature type from the type of current block, in order to avoid
mixing coldest and hottest data/node as much as possible, change
SSR allocation policy to select closer temperature for current
block prior.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:56 -08:00
Chao Yu
55523519bc f2fs: show simple call stack in fault injection message
Previously kernel message can show that in which function we do the
injection, but unfortunately, most of the caller are the same, for
tracking more information of injection path, it needs to show upper
caller's name. This patch supports that ability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:55 -08:00
Yunlei He
dd7b2333e6 f2fs: no need lock_op in f2fs_write_inline_data
Similar as f2fs_write_inode, f2fs_write_inline_data just
mark inode page dirty, so it's no need to write inline data
under read lock of cp_rwsem.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:55 -08:00
Jaegeuk Kim
22ad0b6ab4 f2fs: add bitmaps for empty or full NAT blocks
This patches adds bitmaps to represent empty or full NAT blocks containing
free nid entries.

If we can find valid crc|cp_ver in the last block of checkpoint pack, we'll
use these bitmaps when building free nids. In order to avoid checkpointing
burden, up-to-date bitmaps will be flushed only during umount time. So,
normally we can get this gain, but when power-cut happens, we rely on fsck.f2fs
which recovers this bitmap again.

After this patch, we build free nids from nid #0 at mount time to make more
full NAT blocks, but in runtime, we check empty NAT blocks to load free nids
without loading any NAT pages from disk.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:54 -08:00
Yunlei He
5e8256ac2e f2fs: replace rw semaphore extent_tree_lock with mutex lock
This patch replace rw semaphore extent_tree_lock with mutex lock
for no read cases with this lock.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:53 -08:00
Kinglong Mee
3f2be04304 f2fs: avoid m_flags overlay when allocating more data blocks
When more than one data blocks are allocated, the F2FS_MAP_UNWRITTEN/MAPPED
flags will be overlapped by F2FS_MAP_NEW at the later times.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:52 -08:00
Hou Pengyang
6bfaf7b150 f2fs: remove unsafe bitmap checking
proc A:                      proc B:
- writeback_sb_inodes
- __writeback_single_inode
- do_writepages
- f2fs_write_node_pages
- f2fs_balance_fs_bg         - write_checkpoint
- build_free_nids            - flush_nat_entries
- __build_free_nids          - __flush_nat_entry_set
- ra_meta_pages              - get_next_nat_page
- current_nat_addr           - set_to_next_nat
[do nat_bitmap checking]     - f2fs_change_bit

For proc A, nat_bitmap and nat_bitmap_mir would be compared without lock_op and
nm_i->nat_tree_lock, while proc B is changing nat_bitmap/nat_bitmap_ver in cp.

So it is normal for nat_bitmap/nat_bitmap diffrence under such scenario.

This patch fix this by removing the monitoring point.

[Fix: 599a09b f2fs: check in-memory nat version bitmap]
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:51 -08:00
Hou Pengyang
e15882b6c6 f2fs: init local extent_info to avoid stale stack info in tp
To avoid such stale(fops, blk, len) info in f2fs_lookup_extent_tree_end tp

dio-23095 [005] ...1 17878.856859: f2fs_lookup_extent_tree_end:
			dev = (259,30), ino = 856, pgofs = 0,
			ext_info(fofs: 3441207040, blk: 4294967232, len: 3481143808)

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:50 -08:00
Yunlong Song
77190e1f31 f2fs: remove unnecessary condition check for write_checkpoint in f2fs_gc
Since has_not_enough_free_secs(sbi, 0, 0) must be true if has_not_enough_
free_secs(sbi, sec_freed, 0) is true, write_checkpoint is sure to execute in
both conditions.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:50 -08:00
Jaegeuk Kim
9259228571 f2fs: check discard alignment only for SEQWRITE zones
For converntional zones, we don't need to align discard commands to exact zone
size.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:46 -08:00
Jaegeuk Kim
40465257ac f2fs: wait for discard completion after submission
We don't need to wait for each discard commands when unmounting the image.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:39 -08:00
Jaegeuk Kim
47b8980816 f2fs: much larger batched trim_fs job
We have a kernel thread to issue discard commands, so we can increase the
number of batched discard sections. By default, now it becomes 4GB range.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:30 -08:00
Jaegeuk Kim
ad4d307fce f2fs: avoid very large discard command
This patch adds MAX_DISCARD_BLOCKS() to avoid issuing too much large single
discard command.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27 09:59:20 -08:00
Dave Jiang
11bac80004 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Jaegeuk Kim
70d625cbdb f2fs: do SSR for node segments more aggresively
This patch gives more SSR chances for node blocks.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-24 10:01:41 -08:00
Jaegeuk Kim
c192f7a477 f2fs: find data segments across all the types
Previously, if type is CURSEG_HOT_DATA, we only check CURSEG_HOT_DATA only.
This patch fixes to search all the different types for SSR.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-24 10:01:08 -08:00
Jaegeuk Kim
d0db7703ac f2fs: do SSR in higher priority
Let's check SSR in prior to LFS allocation.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-24 09:39:53 -08:00
Yunlong Song
035e97adab f2fs: do SSR for data when there is enough free space
In allocate_segment_by_default(), need_SSR() already detected it's time to do
SSR. So, let's try to find victims for data segments more aggressively in time.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-24 09:39:52 -08:00
Hou Pengyang
b9cd20619e f2fs: node segment is prior to data segment selected victim
As data segment gc may lead dnode dirty, so the greedy cost for data segment
should be valid blocks * 2, that is data segment is prior to node segment.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-24 09:39:40 -08:00
Yunlong Song
3436c4bdb3 f2fs: put allocate_segment after refresh_sit_entry
SIT information should be updated before segment allocation, since SSR needs
latest valid block information. Current code does not update the old_blkaddr
info in sit_entry, so adjust the allocate_segment to its proper location. Commit
5e443818fa ("f2fs: handle dirty segments inside
refresh_sit_entry") puts it into wrong location.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-24 09:37:30 -08:00
Hou Pengyang
e93b986525 f2fs: add ovp valid_blocks check for bg gc victim to fg_gc
For foreground gc, greedy algorithm should be adapted, which makes
this formula work well:

	(2 * (100 / config.overprovision + 1) + 6)

But currently, we fg_gc have a prior to select bg_gc victim segments to gc
first, these victims are selected by cost-benefit algorithm, we can't guarantee
such segments have the small valid blocks, which may destroy the f2fs rule, on
the worstest case, would consume all the free segments.

This patch fix this by add a filter in check_bg_victims, if segment's has # of
valid blocks over overprovision ratio, skip such segments.

Cc: <stable@vger.kernel.org>
Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-23 11:28:20 -08:00
Jaegeuk Kim
86d54795c9 f2fs: do not wait for writeback in write_begin
Otherwise we can get livelock like below.

[79880.428136] dbench          D    0 18405  18404 0x00000000
[79880.428139] Call Trace:
[79880.428142]  __schedule+0x219/0x6b0
[79880.428144]  schedule+0x36/0x80
[79880.428147]  schedule_timeout+0x243/0x2e0
[79880.428152]  ? update_sd_lb_stats+0x16b/0x5f0
[79880.428155]  ? ktime_get+0x3c/0xb0
[79880.428157]  io_schedule_timeout+0xa6/0x110
[79880.428161]  __lock_page+0xf7/0x130
[79880.428164]  ? unlock_page+0x30/0x30
[79880.428167]  pagecache_get_page+0x16b/0x250
[79880.428171]  grab_cache_page_write_begin+0x20/0x40
[79880.428182]  f2fs_write_begin+0xa2/0xdb0 [f2fs]
[79880.428192]  ? f2fs_mark_inode_dirty_sync+0x16/0x30 [f2fs]
[79880.428197]  ? kmem_cache_free+0x79/0x200
[79880.428203]  ? __mark_inode_dirty+0x17f/0x360
[79880.428206]  generic_perform_write+0xbb/0x190
[79880.428213]  ? file_update_time+0xa4/0xf0
[79880.428217]  __generic_file_write_iter+0x19b/0x1e0
[79880.428226]  f2fs_file_write_iter+0x9c/0x180 [f2fs]
[79880.428231]  __vfs_write+0xc5/0x140
[79880.428235]  vfs_write+0xb2/0x1b0
[79880.428238]  SyS_write+0x46/0xa0
[79880.428242]  entry_SYSCALL_64_fastpath+0x1e/0xad

Fixes: cae96a5c8a ("f2fs: check io submission more precisely")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-23 11:23:27 -08:00
Yunlei He
05eeb118a0 f2fs: replace __get_victim by dirty_segments in FG_GC
In FG_GC process, it will search victim section twice. This will
cause some dirty section with less valid blocks skip garbage
collection.

section # 26425 : valid blocks # 3
142.037567: get_victim_by_default: victim 26425 : valid blocks # 3
142.037585: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
142.039494: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19022 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24
142.070247: new_curseg: Debug: alloc new segment 26746
142.244341: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26054 ofs_unit = 1, pre_victim_secno = 26054, prefree = 0, free = 243
142.254475: do_garbage_collect: Debug: FG_GC, seg_freed = 1
142.293131: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23466 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244
142.319001: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23467 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244
142.368879: get_victim_by_default: victim 26425 : valid blocks # 3
142.368894: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
142.378127: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19612 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24
142.416917: new_curseg: Debug: alloc new segment 26054
142.656794: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 25404 ofs_unit = 1, pre_victim_secno = 25404, prefree = 0, free = 243
142.662139: do_garbage_collect: Debug: FG_GC, seg_freed = 1
142.684159: new_curseg: Debug: alloc new segment 25197
142.685059: get_victim_by_default: victim 26425 : valid blocks # 3
142.685079: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 243
142.701427: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26238 ofs_unit = 1, pre_victim_secno = 26238, prefree = 0, free = 243
142.707105: do_garbage_collect: Debug: FG_GC, seg_freed = 1
142.802444: f2fs_get_victim: dev = (259,30), type = Warm DATA, policy = (Background GC, SSR-mode, Greedy), victim = 23473 ofs_unit = 1, pre_victim_secno = -1, prefree = 0, free = 244
142.804422: get_victim_by_default: victim 26425 : valid blocks # 3
142.804443: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244
142.851567: f2fs_get_victim: dev = (259,30), type = Hot DATA, policy = (Background GC, SSR-mode, Greedy), victim = 19092 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 24
142.865014: new_curseg: Debug: alloc new segment 26238
143.082245: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26307 ofs_unit = 1, pre_victim_secno = 26307, prefree = 0, free = 244
143.088252: do_garbage_collect: Debug: FG_GC, seg_freed = 1
143.128307: new_curseg: Debug: alloc new segment 25404
143.181846: get_victim_by_default: victim 26425 : valid blocks # 3
143.181872: f2fs_get_victim: dev = (259,30), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 26425 ofs_unit = 1, pre_victim_secno = 26425, prefree = 0, free = 244

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-23 11:23:26 -08:00
Jaegeuk Kim
88c5c13a50 f2fs: fix multiple f2fs_add_link() calls having same name
It turns out a stakable filesystem like sdcardfs in AOSP can trigger multiple
vfs_create() to lower filesystem. In that case, f2fs will add multiple dentries
having same name which breaks filesystem consistency.

Until upper layer fixes, let's work around by f2fs, which shows actually not
much performance regression.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-23 11:23:25 -08:00