should vn_fullpath1() ever return a path with "." in it?

Ilia Noskov phantom at phantom.su
Fri Mar 15 13:21:27 UTC 2013


On 03/14/2013 02:10 PM, Ilia Noskov wrote:
> On 03/14/2013 01:08 PM, Konstantin Belousov wrote:
>> On Thu, Mar 14, 2013 at 11:29:11AM +0400, Noskov Ilia wrote:
>>> Strange behavior on nfs-client after apply this patch:
>>>
>>> sysctl debug.disablecwd=0
>>> sysctl debug.disablefullpath=0
>>>
>>> # mount -v -t nfs
>>> 192.168.168.1:/pool on /home (nfs, noatime, nfsv4acls, fsid
>>> 02ff003a3a000000)
>>> # ls /home | wc -l
>>>       4946
>>> # cd /home/user6308/.ro
>>> # time pwd
>>> /home/user6308/.ro
>>> 0.008u 0.269s 0:08.47 3.0%    4+157k 0+0io 0pf+0w
>>> # ktrace -t+ -i pwd
>>>
>>>
>>> ktrace.out is big (1MB). Attach or not?
>>>
>>>
>>>
>>> A small piece of trace:
>>>    19527 pwd      CALL
>>> mmap(0,0x400000,0x3<PROT_READ|PROT_WRITE>,0x1002<MAP_PRIVATE|MAP_ANON>,0xffffffff,0)
>>>
>>>    19527 pwd      RET   mmap 34376515584/0x801000000
>>>    19527 pwd      CALL  __getcwd(0x801006400,0x400)
>>>    19527 pwd      NAMI  ".."
>>>    19527 pwd      NAMI  ".."
>>>    19527 pwd      RET   __getcwd -1 errno 2 No such file or directory
>>>    19527 pwd      CALL  stat(0x800947a14,0x7fffffffd940)
>>>    19527 pwd      NAMI  "/"
>>>    19527 pwd      STRU  struct stat {dev=98, ino=2, mode=drwxr-xr-x ,
>>> nlink=19, uid=0, gid=0, rdev=2120, atime=1363244893, stime=1362653279,
>>> ctime=1362653279, birthtime=1200836451, size=1024, blksize=16384,
>>> blocks=4, flags=0x0 }
>>>    19527 pwd      RET   stat 0
>>>    19527 pwd      CALL  lstat(0x80094779c,0x7fffffffd940)
>>>    19527 pwd      NAMI  "."
>>>    19527 pwd      STRU  struct stat {dev=1230702064, ino=145,
>>> mode=drwxr-xr-x , nlink=2, uid=0, gid=0, rdev=4294967295,
>>> atime=1363244672.246785874, stime=1363244792.864201338,
>>> ctime=1363244792.864201338, birthtime=-1, size=3, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   lstat 0
>>>    19527 pwd      CALL  openat(0xffffff9c,0x80094779b,0x100000,0x2)
>>>    19527 pwd      NAMI  ".."
>>>    19527 pwd      RET   openat 3
>>>    19527 pwd      CALL  fstat(0x3,0x7fffffffd880)
>>>    19527 pwd      STRU  struct stat {dev=1230702064, ino=4,
>>> mode=drwxr-xr-x , nlink=9, uid=0, gid=0, rdev=4294967295,
>>> atime=1363244665.232140704, stime=1363010116.496298252,
>>> ctime=1363010116.496298252, birthtime=-1, size=14, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   fstat 0
>>>    19527 pwd      CALL  fcntl(0x3,F_SETFD,FD_CLOEXEC)
>>>    19527 pwd      RET   fcntl 0
>>>    19527 pwd      CALL  fstatfs(0x3,0x7fffffffd660)
>>>    19527 pwd      RET   fstatfs 0
>>>    19527 pwd      CALL  fstat(0x3,0x7fffffffd940)
>>>    19527 pwd      STRU  struct stat {dev=1230702064, ino=4,
>>> mode=drwxr-xr-x , nlink=9, uid=0, gid=0, rdev=4294967295,
>>> atime=1363244665.232140704, stime=1363010116.496298252,
>>> ctime=1363010116.496298252, birthtime=-1, size=14, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   fstat 0
>>>    19527 pwd      CALL
>>> getdirentries(0x3,0x801018000,0x1000,0x8010160a8)
>>>    19527 pwd      RET   getdirentries 4096/0x1000
>>>    19527 pwd      CALL  fstat(0x3,0x7fffffffd940)
>>>    19527 pwd      STRU  struct stat {dev=1230702064, ino=4,
>>> mode=drwxr-xr-x , nlink=9, uid=0, gid=0, rdev=4294967295,
>>> atime=1363244665.232140704, stime=1363010116.496298252,
>>> ctime=1363010116.496298252, birthtime=-1, size=14, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   fstat 0
>>>    19527 pwd      CALL  openat(0x3,0x80094779b,0x100000,0)
>>>    19527 pwd      NAMI  ".."
>>>    19527 pwd      RET   openat 4
>>> [..............................]
>>>    19527 pwd      CALL  madvise(0x801016000,0x1000,MADV_FREE)
>>>    19527 pwd      RET   madvise 0
>>>    19527 pwd      CALL  madvise(0x801018000,0x2000,MADV_FREE)
>>>    19527 pwd      RET   madvise 0
>>>    19527 pwd      CALL  close(0x3)
>>>    19527 pwd      RET   close 0
>>>    19527 pwd      CALL  fstat(0x4,0x7fffffffd880)
>>>    19527 pwd      STRU  struct stat {dev=973143810, ino=4,
>>> mode=drwxr-xr-x , nlink=4948, uid=0, gid=0, rdev=4294967295,
>>> atime=1363244767.460164771, stime=1363172100.380266923,
>>> ctime=1363172100.380266923, birthtime=-1, size=4948, blksize=4096,
>>> blocks=713, flags=0x0 }
>>>    19527 pwd      RET   fstat 0
>>>    19527 pwd      CALL  fcntl(0x4,F_SETFD,FD_CLOEXEC)
>>>    19527 pwd      RET   fcntl 0
>>>    19527 pwd      CALL  fstatfs(0x4,0x7fffffffd660)
>>>    19527 pwd      RET   fstatfs 0
>>>    19527 pwd      CALL  fstat(0x4,0x7fffffffd940)
>>>    19527 pwd      STRU  struct stat {dev=973143810, ino=4,
>>> mode=drwxr-xr-x , nlink=4948, uid=0, gid=0, rdev=4294967295,
>>> atime=1363244767.460164771, stime=1363172100.380266923,
>>> ctime=1363172100.380266923, birthtime=-1, size=4948, blksize=4096,
>>> blocks=713, flags=0x0 }
>>>    19527 pwd      RET   fstat 0
>>>    19527 pwd      CALL
>>> getdirentries(0x4,0x801018000,0x1000,0x8010160a8)
>>>    19527 pwd      RET   getdirentries 4096/0x1000
>>>    19527 pwd      CALL  fstatat(0x4,0x801018030,0x7fffffffd940,0x200)
>>>    19527 pwd      NAMI  "user6158"
>>>    19527 pwd      STRU  struct stat {dev=1774902232, ino=4,
>>> mode=drwxr-xr-x , nlink=9, uid=0, gid=0, rdev=4294967295,
>>> atime=1363009687.040357529, stime=1363010116.496298252,
>>> ctime=1363010116.496298252, birthtime=-1, size=14, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   fstatat 0
>>>    19527 pwd      CALL  fstatat(0x4,0x80101804c,0x7fffffffd940,0x200)
>>>    19527 pwd      NAMI  "user2289"
>>>    19527 pwd      STRU  struct stat {dev=1988229825, ino=4,
>>> mode=drwxr-xr-x , nlink=9, uid=0, gid=0, rdev=4294967295,
>>> atime=1363009687.040357529, stime=1363010116.496298252,
>>> ctime=1363010116.496298252, birthtime=-1, size=14, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   fstatat 0
>>>    19527 pwd      CALL  fstatat(0x4,0x801018068,0x7fffffffd940,0x200)
>>>    19527 pwd      NAMI  "user4761"
>>>    19527 pwd      STRU  struct stat {dev=2438657130, ino=4,
>>> mode=drwxr-xr-x , nlink=9, uid=0, gid=0, rdev=4294967295,
>>> atime=1363009687.040357529, stime=1363010116.496298252,
>>> ctime=1363010116.496298252, birthtime=-1, size=14, blksize=4096,
>>> blocks=3, flags=0x0 }
>>>    19527 pwd      RET   fstatat 0
>>>    19527 pwd      CALL  fstatat(0x4,0x801018084,0x7fffffffd940,0x200)
>>>    19527 pwd      NAMI  "user6055"
>>> [.........................................]
>>>
>>> and next get stat of all directories in /home
>>
>> Slightly different version of the patch was committed as r247560.
>>
>> The situation could only happen if the parent directory contains the "."
>> entry with inode number equal to the inode number of the subdirectory.
>> Can you confirm that this is your case ?
>>
>
> Yes, it is.
> I'll try again on the latest snapshot. Thanks!
>

Yes.
On latest r248313 similar situation - if path contains "." then 
nfsclient get stat of all directories in /home.





-- 
      Best Regards,

      Ilia Noskov
      Regional Network Information Center (RU-CENTER)
      phone: +7 495 737-0601
      fax: +7 495 737-0602
      http://www.nic.ru


More information about the freebsd-fs mailing list