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  1. 06 9月, 2019 2 次提交
    • R
      xfs: fix missed wakeup on l_flush_wait · cdea5459
      由 Rik van Riel 提交于 
      The code in xlog_wait uses the spinlock to make adding the task to
the wait queue, and setting the task state to UNINTERRUPTIBLE atomic
with respect to the waker.

Doing the wakeup after releasing the spinlock opens up the following
race condition:

Task 1					task 2
add task to wait queue
					wake up task
set task state to UNINTERRUPTIBLE

This issue was found through code inspection as a result of kworkers
being observed stuck in UNINTERRUPTIBLE state with an empty
wait queue. It is rare and largely unreproducable.

Simply moving the spin_unlock to after the wake_up_all results
in the waker not being able to see a task on the waitqueue before
it has set its state to UNINTERRUPTIBLE.

This bug dates back to the conversion of this code to generic
waitqueue infrastructure from a counting semaphore back in 2008
which didn't place the wakeups consistently w.r.t. to the relevant
spin locks.

[dchinner: Also fix a similar issue in the shutdown path on
xc_commit_wait. Update commit log with more details of the issue.]

Fixes: d748c623 ("[XFS] Convert l_flushsema to a sv_t")
Reported-by: NChris Mason <clm@fb.com>
Signed-off-by: NRik van Riel <riel@surriel.com>
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>
      cdea5459
    • D
      xfs: push the AIL in xlog_grant_head_wake · 7c107afb
      由 Dave Chinner 提交于 
      In the situation where the log is full and the CIL has not recently
flushed, the AIL push threshold is throttled back to the where the
last write of the head of the log was completed. This is stored in
log->l_last_sync_lsn. Hence if the CIL holds > 25% of the log space
pinned by flushes and/or aggregation in progress, we can get the
situation where the head of the log lags a long way behind the
reservation grant head.

When this happens, the AIL push target is trimmed back from where
the reservation grant head wants to push the log tail to, back to
where the head of the log currently is. This means the push target
doesn't reach far enough into the log to actually move the tail
before the transaction reservation goes to sleep.

When the CIL push completes, it moves the log head forward such that
the AIL push target can now be moved, but that has no mechanism for
puhsing the log tail. Further, if the next tail movement of the log
is not large enough wake the waiter (i.e. still not enough space for
it to have a reservation granted), we don't wake anything up, and
hence we do not update the AIL push target to take into account the
head of the log moving and allowing the push target to be moved
forwards.

To avoid this particular condition, if we fail to wake the first
waiter on the grant head because we don't have enough space,
push on the AIL again. This will pick up any movement of the log
head and allow the push target to move forward due to completion of
CIL pushing.
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>
      7c107afb
  3. 27 8月, 2019 2 次提交
    • D
      xfs: add kmem_alloc_io() · f8f9ee47
      由 Dave Chinner 提交于 
      Memory we use to submit for IO needs strict alignment to the
underlying driver contraints. Worst case, this is 512 bytes. Given
that all allocations for IO are always a power of 2 multiple of 512
bytes, the kernel heap provides natural alignment for objects of
these sizes and that suffices.

Until, of course, memory debugging of some kind is turned on (e.g.
red zones, poisoning, KASAN) and then the alignment of the heap
objects is thrown out the window. Then we get weird IO errors and
data corruption problems because drivers don't validate alignment
and do the wrong thing when passed unaligned memory buffers in bios.

TO fix this, introduce kmem_alloc_io(), which will guaranteeat least
512 byte alignment of buffers for IO, even if memory debugging
options are turned on. It is assumed that the minimum allocation
size will be 512 bytes, and that sizes will be power of 2 mulitples
of 512 bytes.

Use this everywhere we allocate buffers for IO.

This no longer fails with log recovery errors when KASAN is enabled
due to the brd driver not handling unaligned memory buffers:

# mkfs.xfs -f /dev/ram0 ; mount /dev/ram0 /mnt/test
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-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>
      f8f9ee47
    • T
      fs: xfs: Remove KM_NOSLEEP and KM_SLEEP. · 707e0dda
      由 Tetsuo Handa 提交于 
      Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      707e0dda
  5. 04 8月, 2019 1 次提交
    • T
      fs: xfs: xfs_log: Don't use KM_MAYFAIL at xfs_log_reserve(). · 294fc7a4
      由 Tetsuo Handa 提交于 
      When the system is close-to-OOM, fsync() may fail due to -ENOMEM because
xfs_log_reserve() is using KM_MAYFAIL. It is a bad thing to fail writeback
operation due to user-triggerable OOM condition. Since we are not using
KM_MAYFAIL at xfs_trans_alloc() before calling xfs_log_reserve(), let's
use the same flags at xfs_log_reserve().

  oom-torture: page allocation failure: order:0, mode:0x46c40(GFP_NOFS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP), nodemask=(null)
  CPU: 7 PID: 1662 Comm: oom-torture Kdump: loaded Not tainted 5.3.0-rc2+ #925
  Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00
  Call Trace:
   dump_stack+0x67/0x95
   warn_alloc+0xa9/0x140
   __alloc_pages_slowpath+0x9a8/0xbce
   __alloc_pages_nodemask+0x372/0x3b0
   alloc_slab_page+0x3a/0x8d0
   new_slab+0x330/0x420
   ___slab_alloc.constprop.94+0x879/0xb00
   __slab_alloc.isra.89.constprop.93+0x43/0x6f
   kmem_cache_alloc+0x331/0x390
   kmem_zone_alloc+0x9f/0x110 [xfs]
   kmem_zone_alloc+0x9f/0x110 [xfs]
   xlog_ticket_alloc+0x33/0xd0 [xfs]
   xfs_log_reserve+0xb4/0x410 [xfs]
   xfs_trans_reserve+0x1d1/0x2b0 [xfs]
   xfs_trans_alloc+0xc9/0x250 [xfs]
   xfs_setfilesize_trans_alloc.isra.27+0x44/0xc0 [xfs]
   xfs_submit_ioend.isra.28+0xa5/0x180 [xfs]
   xfs_vm_writepages+0x76/0xa0 [xfs]
   do_writepages+0x17/0x80
   __filemap_fdatawrite_range+0xc1/0xf0
   file_write_and_wait_range+0x53/0xa0
   xfs_file_fsync+0x87/0x290 [xfs]
   vfs_fsync_range+0x37/0x80
   do_fsync+0x38/0x60
   __x64_sys_fsync+0xf/0x20
   do_syscall_64+0x4a/0x1c0
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: eb01c9cd ("[XFS] Remove the xlog_ticket allocator")
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
      294fc7a4
  7. 03 7月, 2019 1 次提交
  9. 29 6月, 2019 18 次提交
  11. 24 5月, 2019 1 次提交
    • D
      xfs: fix broken log reservation debugging · d31d7185
      由 Darrick J. Wong 提交于 
      xlog_print_tic_res() is supposed to print a human readable string for
each element of the log ticket reservation array.  Unfortunately, I
forgot to update the string array when we added rmap & reflink support,
so the debug message prints "region[3]: (null) - 352 bytes" which isn't
useful at all.  Add the missing elements and add a build check so that
we don't forget again to add a string when adding a new XLOG_REG_TYPE.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
      d31d7185
  13. 15 4月, 2019 1 次提交
  15. 03 8月, 2018 1 次提交
  17. 01 8月, 2018 1 次提交
  19. 24 7月, 2018 2 次提交
  21. 09 6月, 2018 1 次提交
  23. 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
  25. 10 5月, 2018 2 次提交
  27. 10 4月, 2018 1 次提交
  29. 24 3月, 2018 2 次提交
  31. 15 3月, 2018 3 次提交