Re: [RFC PATCH] xfs: drop experimental warning for fsdax

Shiyang Ruan
2022-09-28T14:46:37Z

在 2022/9/28 7:51, Dave Chinner 写道:
> On Tue, Sep 27, 2022 at 09:02:48AM -0700, Darrick J. Wong wrote:
>> On Tue, Sep 27, 2022 at 02:53:14PM +0800, Shiyang Ruan wrote:
...
>>>
>>> I have tested these two mode for many times:
>>>
>>> xfs_dax mode did failed so many cases. (If you tested with this "drop"
>>> patch, some warning around "dax_dedupe_file_range_compare()" won't occur any
>>> more.) I think warning around "dax_disassociate_entry()" is a problem with
>>> concurrency. Still looking into it.
>>>
>>> But xfs_dax_noreflink didn't have so many failure, just 3 in my environment:
>>> Failures: generic/471 generic/519 xfs/148. I am thinking that did you
>>> forget to reformat the TEST_DEV to be non-reflink before run the test? If
>>> so it will make sense.
>
> No, I did not forget to turn off reflink for the test device:
>
> # ./run_check.sh --mkfs-opts "-m reflink=0,rmapbt=1" --run-opts "-s xfs_dax_noreflink -g auto"
> umount: /mnt/test: not mounted.
> umount: /mnt/scratch: not mounted.
> wrote 8589934592/8589934592 bytes at offset 0
> 8.000 GiB, 8192 ops; 0:00:03.99 (2.001 GiB/sec and 2049.0850 ops/sec)
> wrote 8589934592/8589934592 bytes at offset 0
> 8.000 GiB, 8192 ops; 0:00:04.13 (1.936 GiB/sec and 1982.5453 ops/sec)
> meta-data=/dev/pmem0 isize=512 agcount=4, agsize=524288 blks
> = sectsz=4096 attr=2, projid32bit=1
> = crc=1 finobt=1, sparse=1, rmapbt=1
> = reflink=0 bigtime=1 inobtcount=1 nrext64=0
> data = bsize=4096 blocks=2097152, imaxpct=25
> = sunit=0 swidth=0 blks
> naming =version 2 bsize=4096 ascii-ci=0, ftype=1
> log =internal log bsize=4096 blocks=16384, version=2
> = sectsz=4096 sunit=1 blks, lazy-count=1
> realtime =none extsz=4096 blocks=0, rtextents=0
> .....
> Running: MOUNT_OPTIONS= ./check -R xunit -b -s xfs_dax_noreflink -g auto
> SECTION -- xfs_dax_noreflink
> FSTYP -- xfs (debug)
> PLATFORM -- Linux/x86_64 test3 6.0.0-rc6-dgc+ #1543 SMP PREEMPT_DYNAMIC Mon Sep 19 07:46:37 AEST 2022
> MKFS_OPTIONS -- -f -m reflink=0,rmapbt=1 /dev/pmem1
> MOUNT_OPTIONS -- -o dax=always -o context=system_u:object_r:root_t:s0 /dev/pmem1 /mnt/scratch
>
> So, yeah, reflink was turned off on both test and scratch devices,
> and dax=always on both the test and scratch devices was used to
> ensure that DAX was always in use.
>
>
>> FWIW I saw dmesg failures in xfs/517 and xfs/013 starting with 6.0-rc5,
>> and I haven't even turned on reflink yet:
>>
>> run fstests xfs/517 at 2022-09-26 19:53:34
>> XFS (pmem1): EXPERIMENTAL Large extent counts feature in use. Use at your own risk!
>> XFS (pmem1): Mounting V5 Filesystem
>> XFS (pmem1): Ending clean mount
>> XFS (pmem1): Quotacheck needed: Please wait.
>> XFS (pmem1): Quotacheck: Done.
>> XFS (pmem1): Unmounting Filesystem
>> XFS (pmem0): EXPERIMENTAL online scrub feature in use. Use at your own risk!
>> XFS (pmem1): EXPERIMENTAL Large extent counts feature in use. Use at your own risk!
>> XFS (pmem1): Mounting V5 Filesystem
>> XFS (pmem1): Ending clean mount
>> XFS (pmem1): Quotacheck needed: Please wait.
>> XFS (pmem1): Quotacheck: Done.
>> ------------[ cut here ]------------
>> WARNING: CPU: 1 PID: 415317 at fs/dax.c:380 dax_insert_entry+0x22d/0x320
>> Modules linked in: xfs nft_chain_nat xt_REDIRECT nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_tcpudp ip_set_hash_ip ip_set_hash_net xt_set nft_compat ip_set_hash_mac ip_set nf_tables libcrc32c bfq nfnetlink pvpanic_mmio pvpanic nd_pmem dax_pmem nd_btt sch_fq_codel fuse configfs ip_tables x_tables overlay nfsv4 af_packet [last unloaded: scsi_d
>>
>> CPU: 1 PID: 415317 Comm: fsstress Tainted: G W 6.0.0-rc7-xfsx #rc7 727341edbd0773a36b78b09dab448fa1896eb3a5
>> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
>> RIP: 0010:dax_insert_entry+0x22d/0x320
>> Code: e0 48 83 c4 20 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 8b 58 20 48 8d 53 01 e9 62 ff ff ff 48 8b 58 20 48 8d 53 01 e9 4d ff ff ff <0f> 0b e9 6d ff ff ff 31 f6 48 89 ef e8 72 74 12 00 eb a1 83 e0 02
>> RSP: 0000:ffffc90004693b28 EFLAGS: 00010002
>> RAX: ffffea0010a20480 RBX: 0000000000000001 RCX: 0000000000000001
>> RDX: ffffea0000000000 RSI: 0000000000000033 RDI: ffffea0010a204c0
>> RBP: ffffc90004693c08 R08: 0000000000000000 R09: 0000000000000000
>> R10: ffff88800c226228 R11: 0000000000000001 R12: 0000000000000011
>> R13: ffff88800c226228 R14: ffffc90004693e08 R15: 0000000000000000
>> FS: 00007f3aad8db740(0000) GS:ffff88803ed00000(0000) knlGS:0000000000000000
>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00007f3aad8d1000 CR3: 0000000043104003 CR4: 00000000001706e0
>> Call Trace:
>> <TASK>
>> dax_fault_iter+0x26e/0x670
>> dax_iomap_pte_fault+0x1ab/0x3e0
>> __xfs_filemap_fault+0x32f/0x5a0 [xfs c617487f99e14abfa5deb24e923415b927df3d4b]
>> __do_fault+0x30/0x1e0
>> do_fault+0x316/0x6d0
>> ? mmap_region+0x2a5/0x620
>> __handle_mm_fault+0x649/0x1250
>> handle_mm_fault+0xc1/0x220
>> do_user_addr_fault+0x1ac/0x610
>> ? _copy_to_user+0x63/0x80
>> exc_page_fault+0x63/0x130
>> asm_exc_page_fault+0x22/0x30
>> RIP: 0033:0x7f3aada7f1ca
>> Code: c5 fe 7f 07 c5 fe 7f 47 20 c5 fe 7f 47 40 c5 fe 7f 47 60 c5 f8 77 c3 66 0f 1f 84 00 00 00 00 00 40 0f b6 c6 48 89 d1 48 89 fa <f3> aa 48 89 d0 c5 f8 77 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90
>> RSP: 002b:00007ffe47afa688 EFLAGS: 00010206
>> RAX: 000000000000002e RBX: 0000000000033000 RCX: 000000000000999c
>> RDX: 00007f3aad8d1000 RSI: 000000000000002e RDI: 00007f3aad8d1000
>> RBP: 0000558851e13240 R08: 0000000000000000 R09: 0000000000033000
>> R10: 0000000000000008 R11: 0000000000000246 R12: 028f5c28f5c28f5c
>> R13: 8f5c28f5c28f5c29 R14: 000000000000999c R15: 0000000000001c81
>> </TASK>
>> ---[ end trace 0000000000000000 ]---
>> XFS (pmem0): Unmounting Filesystem
>> XFS (pmem1): EXPERIMENTAL online scrub feature in use. Use at your own risk!
>> XFS (pmem1): *** REPAIR SUCCESS ino 0x80 type probe agno 0x0 inum 0x0 gen 0x0 flags 0x80000001 error 0
>> XFS (pmem1): Unmounting Filesystem
>> XFS (pmem1): EXPERIMENTAL Large extent counts feature in use. Use at your own risk!
>> XFS (pmem1): Mounting V5 Filesystem
>> XFS (pmem1): Ending clean mount
>> XFS (pmem1): Unmounting Filesystem
>
> Yup, that's the same as what I'm seeing.

Could you send me your kernel config (or other configs needed for the
test)? I still cannot reproduce this warning when reflink is off, even
without this drop patch. Maybe something different in config file?

PS: I specifically tried the two cases Darrick mentioned (on v6.0-rc6):

[root@f33 xfstests-dev]# mkfs.xfs -m reflink=0,rmapbt=1 /dev/pmem0.1 -f
meta-data=/dev/pmem0.1 isize=512 agcount=4, agsize=257920 blks
= sectsz=4096 attr=2, projid32bit=1
= crc=1 finobt=1, sparse=1, rmapbt=1
= reflink=0 bigtime=1 inobtcount=1
nrext64=0
data = bsize=4096 blocks=1031680, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0, ftype=1
log =internal log bsize=4096 blocks=16384, version=2
= sectsz=4096 sunit=1 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@f33 xfstests-dev]# mkfs.xfs -m reflink=0,rmapbt=1 /dev/pmem0 -f
meta-data=/dev/pmem0 isize=512 agcount=4, agsize=257920 blks
= sectsz=4096 attr=2, projid32bit=1
= crc=1 finobt=1, sparse=1, rmapbt=1
= reflink=0 bigtime=1 inobtcount=1
nrext64=0
data = bsize=4096 blocks=1031680, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0, ftype=1
log =internal log bsize=4096 blocks=16384, version=2
= sectsz=4096 sunit=1 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@f33 xfstests-dev]# ./check xfs/013 xfs/517
FSTYP -- xfs (debug)
PLATFORM -- Linux/x86_64 f33 6.0.0-rc6 #84 SMP PREEMPT_DYNAMIC Wed
Sep 28 18:27:33 CST 2022
MKFS_OPTIONS -- -f -m reflink=0,rmapbt=1 /dev/pmem0.1
MOUNT_OPTIONS -- -o dax -o context=system_u:object_r:root_t:s0
/dev/pmem0.1 /mnt/scratch

xfs/013 127s ... 166s
xfs/517 66s ... 66s
Ran: xfs/013 xfs/517
Passed all 2 tests

--
Thanks,
Ruan.

>
> Cheers,
>
> Dave.