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  1. 30 10月, 2019 10 次提交
  3. 21 10月, 2019 1 次提交
  5. 06 9月, 2019 1 次提交
    • D
      xfs: prevent CIL push holdoff in log recovery · 8ab39f11
      由 Dave Chinner 提交于 
      generic/530 on a machine with enough ram and a non-preemptible
kernel can run the AGI processing phase of log recovery enitrely out
of cache. This means it never blocks on locks, never waits for IO
and runs entirely through the unlinked lists until it either
completes or blocks and hangs because it has run out of log space.

It runs out of log space because the background CIL push is
scheduled but never runs. queue_work() queues the CIL work on the
current CPU that is busy, and the workqueue code will not run it on
any other CPU. Hence if the unlinked list processing never yields
the CPU voluntarily, the push work is delayed indefinitely. This
results in the CIL aggregating changes until all the log space is
consumed.

When the log recoveyr processing evenutally blocks, the CIL flushes
but because the last iclog isn't submitted for IO because it isn't
full, the CIL flush never completes and nothing ever moves the log
head forwards, or indeed inserts anything into the tail of the log,
and hence nothing is able to get the log moving again and recovery
hangs.

There are several problems here, but the two obvious ones from
the trace are that:
	a) log recovery does not yield the CPU for over 4 seconds,
	b) binding CIL pushes to a single CPU is a really bad idea.

This patch addresses just these two aspects of the problem, and are
suitable for backporting to work around any issues in older kernels.
The more fundamental problem of preventing the CIL from consuming
more than 50% of the log without committing will take more invasive
and complex work, so will be done as followup work.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      8ab39f11
  7. 30 8月, 2019 1 次提交
    • D
      fs: Fill in max and min timestamps in superblock · 22b13969
      由 Deepa Dinamani 提交于 
      Fill in the appropriate limits to avoid inconsistencies
in the vfs cached inode times when timestamps are
outside the permitted range.

Even though some filesystems are read-only, fill in the
timestamps to reflect the on-disk representation.
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Acked-By: NTigran Aivazian <aivazian.tigran@gmail.com>
Acked-by: NJeff Layton <jlayton@kernel.org>
Cc: aivazian.tigran@gmail.com
Cc: al@alarsen.net
Cc: coda@cs.cmu.edu
Cc: darrick.wong@oracle.com
Cc: dushistov@mail.ru
Cc: dwmw2@infradead.org
Cc: hch@infradead.org
Cc: jack@suse.com
Cc: jaharkes@cs.cmu.edu
Cc: luisbg@kernel.org
Cc: nico@fluxnic.net
Cc: phillip@squashfs.org.uk
Cc: richard@nod.at
Cc: salah.triki@gmail.com
Cc: shaggy@kernel.org
Cc: linux-xfs@vger.kernel.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: reiserfs-devel@vger.kernel.org
      22b13969
  9. 29 6月, 2019 3 次提交
  11. 12 6月, 2019 1 次提交
  13. 02 5月, 2019 1 次提交
  15. 30 4月, 2019 1 次提交
  17. 27 4月, 2019 2 次提交
  19. 17 4月, 2019 1 次提交
  21. 07 4月, 2019 1 次提交
    • C
      block: remove CONFIG_LBDAF · 72deb455
      由 Christoph Hellwig 提交于 
      Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures.  These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time.  Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.

Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      72deb455
  23. 21 2月, 2019 1 次提交
    • C
      xfs: introduce an always_cow mode · 66ae56a5
      由 Christoph Hellwig 提交于 
      Add a mode where XFS never overwrites existing blocks in place.  This
is to aid debugging our COW code, and also put infatructure in place
for things like possible future support for zoned block devices, which
can't support overwrites.

This mode is enabled globally by doing a:

    echo 1 > /sys/fs/xfs/debug/always_cow

Note that the parameter is global to allow running all tests in xfstests
easily in this mode, which would not easily be possible with a per-fs
sysfs file.

In always_cow mode persistent preallocations are disabled, and fallocate
will fail when called with a 0 mode (with our without
FALLOC_FL_KEEP_SIZE), and not create unwritten extent for zeroed space
when called with FALLOC_FL_ZERO_RANGE or FALLOC_FL_UNSHARE_RANGE.

There are a few interesting xfstests failures when run in always_cow
mode:

 - generic/392 fails because the bytes used in the file used to test
   hole punch recovery are less after the log replay.  This is
   because the blocks written and then punched out are only freed
   with a delay due to the logging mechanism.
 - xfs/170 will fail as the already fragile file streams mechanism
   doesn't seem to interact well with the COW allocator
 - xfs/180 xfs/182 xfs/192 xfs/198 xfs/204 and xfs/208 will claim
   the file system is badly fragmented, but there is not much we
   can do to avoid that when always writing out of place
 - xfs/205 fails because overwriting a file in always_cow mode
   will require new space allocation and the assumption in the
   test thus don't work anymore.
 - xfs/326 fails to modify the file at all in always_cow mode after
   injecting the refcount error, leading to an unexpected md5sum
   after the remount, but that again is expected
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      66ae56a5
  25. 15 2月, 2019 1 次提交
  27. 13 12月, 2018 2 次提交
  29. 18 10月, 2018 2 次提交
  31. 30 7月, 2018 1 次提交
  33. 27 7月, 2018 1 次提交
  35. 12 7月, 2018 1 次提交
  37. 09 6月, 2018 1 次提交
  39. 07 6月, 2018 1 次提交
    • D
      xfs: convert to SPDX license tags · 0b61f8a4
      由 Dave Chinner 提交于 
      Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
	echo $f
	cat $f | awk -f hdr.awk > $f.new
	mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
	hdr = 1.0
	tag = "GPL-2.0"
	str = ""
}

/^ \* This program is free software/ {
	hdr = 2.0;
	next
}

/any later version./ {
	tag = "GPL-2.0+"
	next
}

/^ \*\// {
	if (hdr > 0.0) {
		print "// SPDX-License-Identifier: " tag
		print str
		print $0
		str=""
		hdr = 0.0
		next
	}
	print $0
	next
}

/^ \* / {
	if (hdr > 1.0)
		next
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
	next
}

/^ \*/ {
	if (hdr > 0.0)
		next
	print $0
	next
}

// {
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
}

END { }
$
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      0b61f8a4
  41. 31 5月, 2018 3 次提交
  43. 16 5月, 2018 3 次提交
    • D
      xfs: clear sb->s_fs_info on mount failure · c9fbd7bb
      由 Dave Chinner 提交于 
      We recently had an oops reported on a 4.14 kernel in
xfs_reclaim_inodes_count() where sb->s_fs_info pointed to garbage
and so the m_perag_tree lookup walked into lala land.

Essentially, the machine was under memory pressure when the mount
was being run, xfs_fs_fill_super() failed after allocating the
xfs_mount and attaching it to sb->s_fs_info. It then cleaned up and
freed the xfs_mount, but the sb->s_fs_info field still pointed to
the freed memory. Hence when the superblock shrinker then ran
it fell off the bad pointer.

With the superblock shrinker problem fixed at teh VFS level, this
stale s_fs_info pointer is still a problem - we use it
unconditionally in ->put_super when the superblock is being torn
down, and hence we can still trip over it after a ->fill_super
call failure. Hence we need to clear s_fs_info if
xfs-fs_fill_super() fails, and we need to check if it's valid in
the places it can potentially be dereferenced after a ->fill_super
failure.
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      c9fbd7bb
    • D
      xfs: add mount delay debug option · dae5cd81
      由 Dave Chinner 提交于 
      Similar to log_recovery_delay, this delay occurs between the VFS
superblock being initialised and the xfs_mount being fully
initialised. It also poisons the per-ag radix tree node so that it
can be used for triggering shrinker races during mount
such as the following:

<run memory pressure workload in background>

$ cat dirty-mount.sh
#! /bin/bash

umount -f /dev/pmem0
mkfs.xfs -f /dev/pmem0
mount /dev/pmem0 /mnt/test
rm -f /mnt/test/foo
xfs_io -fxc "pwrite 0 4k" -c fsync -c "shutdown" /mnt/test/foo
umount /dev/pmem0

# let's crash it now!
echo 30 > /sys/fs/xfs/debug/mount_delay
mount /dev/pmem0 /mnt/test
echo 0 > /sys/fs/xfs/debug/mount_delay
umount /dev/pmem0
$ sudo ./dirty-mount.sh
.....
[   60.378118] CPU: 3 PID: 3577 Comm: fs_mark Tainted: G      D W        4.16.0-rc5-dgc #440
[   60.378120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   60.378124] RIP: 0010:radix_tree_next_chunk+0x76/0x320
[   60.378127] RSP: 0018:ffffc9000276f4f8 EFLAGS: 00010282
[   60.383670] RAX: a5a5a5a5a5a5a5a4 RBX: 0000000000000010 RCX: 000000000000001a
[   60.385277] RDX: 0000000000000000 RSI: ffffc9000276f540 RDI: 0000000000000000
[   60.386554] RBP: 0000000000000000 R08: 0000000000000000 R09: a5a5a5a5a5a5a5a5
[   60.388194] R10: 0000000000000006 R11: 0000000000000001 R12: ffffc9000276f598
[   60.389288] R13: 0000000000000040 R14: 0000000000000228 R15: ffff880816cd6458
[   60.390827] FS:  00007f5c124b9740(0000) GS:ffff88083fc00000(0000) knlGS:0000000000000000
[   60.392253] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   60.393423] CR2: 00007f5c11bba0b8 CR3: 000000035580e001 CR4: 00000000000606e0
[   60.394519] Call Trace:
[   60.395252]  radix_tree_gang_lookup_tag+0xc4/0x130
[   60.395948]  xfs_perag_get_tag+0x37/0xf0
[   60.396522]  xfs_reclaim_inodes_count+0x32/0x40
[   60.397178]  xfs_fs_nr_cached_objects+0x11/0x20
[   60.397837]  super_cache_count+0x35/0xc0
[   60.399159]  shrink_slab.part.66+0xb1/0x370
[   60.400194]  shrink_node+0x7e/0x1a0
[   60.401058]  try_to_free_pages+0x199/0x470
[   60.402081]  __alloc_pages_slowpath+0x3a1/0xd20
[   60.403729]  __alloc_pages_nodemask+0x1c3/0x200
[   60.404941]  cache_grow_begin+0x20b/0x2e0
[   60.406164]  fallback_alloc+0x160/0x200
[   60.407088]  kmem_cache_alloc+0x111/0x4e0
[   60.408038]  ? xfs_buf_rele+0x61/0x430
[   60.408925]  kmem_zone_alloc+0x61/0xe0
[   60.409965]  xfs_inode_alloc+0x24/0x1d0
.....
Signed-Off-By: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      dae5cd81
    • D
      xfs: halt auto-reclamation activities while rebuilding rmap · d6b636eb
      由 Darrick J. Wong 提交于 
      Rebuilding the reverse-mapping tree requires us to quiesce all inodes in
the filesystem, so we must stop background reclamation of post-EOF and
CoW prealloc blocks.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      d6b636eb