1. 16 10月, 2007 10 次提交
  2. 15 10月, 2007 2 次提交
  3. 18 9月, 2007 1 次提交
  4. 18 7月, 2007 1 次提交
    • R
      Freezer: make kernel threads nonfreezable by default · 83144186
      Rafael J. Wysocki 提交于
      Currently, the freezer treats all tasks as freezable, except for the kernel
      threads that explicitly set the PF_NOFREEZE flag for themselves.  This
      approach is problematic, since it requires every kernel thread to either
      set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
      care for the freezing of tasks at all.
      
      It seems better to only require the kernel threads that want to or need to
      be frozen to use some freezer-related code and to remove any
      freezer-related code from the other (nonfreezable) kernel threads, which is
      done in this patch.
      
      The patch causes all kernel threads to be nonfreezable by default (ie.  to
      have PF_NOFREEZE set by default) and introduces the set_freezable()
      function that should be called by the freezable kernel threads in order to
      unset PF_NOFREEZE.  It also makes all of the currently freezable kernel
      threads call set_freezable(), so it shouldn't cause any (intentional)
      change of behaviour to appear.  Additionally, it updates documentation to
      describe the freezing of tasks more accurately.
      
      [akpm@linux-foundation.org: build fixes]
      Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
      Acked-by: NNigel Cunningham <nigel@nigel.suspend2.net>
      Cc: Pavel Machek <pavel@ucw.cz>
      Cc: Oleg Nesterov <oleg@tv-sign.ru>
      Cc: Gautham R Shenoy <ego@in.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      83144186
  5. 14 7月, 2007 2 次提交
    • D
      [XFS] Fix remount,readonly path to flush everything correctly. · 516b2e7c
      David Chinner 提交于
      The remount readonly path can fail to writeback properly because we still
      have active transactions after calling xfs_quiesce_fs(). Further
      investigation shows that this path is broken in the same ways that the xfs
      freeze path was broken so fix it the same way.
      
      SGI-PV: 964464
      SGI-Modid: xfs-linux-melb:xfs-kern:28869a
      Signed-off-by: NDavid Chinner <dgc@sgi.com>
      Signed-off-by: NChristoph Hellwig <hch@infradead.org>
      Signed-off-by: NTim Shimmin <tes@sgi.com>
      516b2e7c
    • D
      [XFS] Lazy Superblock Counters · 92821e2b
      David Chinner 提交于
      When we have a couple of hundred transactions on the fly at once, they all
      typically modify the on disk superblock in some way.
      create/unclink/mkdir/rmdir modify inode counts, allocation/freeing modify
      free block counts.
      
      When these counts are modified in a transaction, they must eventually lock
      the superblock buffer and apply the mods. The buffer then remains locked
      until the transaction is committed into the incore log buffer. The result
      of this is that with enough transactions on the fly the incore superblock
      buffer becomes a bottleneck.
      
      The result of contention on the incore superblock buffer is that
      transaction rates fall - the more pressure that is put on the superblock
      buffer, the slower things go.
      
      The key to removing the contention is to not require the superblock fields
      in question to be locked. We do that by not marking the superblock dirty
      in the transaction. IOWs, we modify the incore superblock but do not
      modify the cached superblock buffer. In short, we do not log superblock
      modifications to critical fields in the superblock on every transaction.
      In fact we only do it just before we write the superblock to disk every
      sync period or just before unmount.
      
      This creates an interesting problem - if we don't log or write out the
      fields in every transaction, then how do the values get recovered after a
      crash? the answer is simple - we keep enough duplicate, logged information
      in other structures that we can reconstruct the correct count after log
      recovery has been performed.
      
      It is the AGF and AGI structures that contain the duplicate information;
      after recovery, we walk every AGI and AGF and sum their individual
      counters to get the correct value, and we do a transaction into the log to
      correct them. An optimisation of this is that if we have a clean unmount
      record, we know the value in the superblock is correct, so we can avoid
      the summation walk under normal conditions and so mount/recovery times do
      not change under normal operation.
      
      One wrinkle that was discovered during development was that the blocks
      used in the freespace btrees are never accounted for in the AGF counters.
      This was once a valid optimisation to make; when the filesystem is full,
      the free space btrees are empty and consume no space. Hence when it
      matters, the "accounting" is correct. But that means the when we do the
      AGF summations, we would not have a correct count and xfs_check would
      complain. Hence a new counter was added to track the number of blocks used
      by the free space btrees. This is an *on-disk format change*.
      
      As a result of this, lazy superblock counters are a mkfs option and at the
      moment on linux there is no way to convert an old filesystem. This is
      possible - xfs_db can be used to twiddle the right bits and then
      xfs_repair will do the format conversion for you. Similarly, you can
      convert backwards as well. At some point we'll add functionality to
      xfs_admin to do the bit twiddling easily....
      
      SGI-PV: 964999
      SGI-Modid: xfs-linux-melb:xfs-kern:28652a
      Signed-off-by: NDavid Chinner <dgc@sgi.com>
      Signed-off-by: NChristoph Hellwig <hch@infradead.org>
      Signed-off-by: NTim Shimmin <tes@sgi.com>
      92821e2b
  6. 17 5月, 2007 1 次提交
    • C
      Remove SLAB_CTOR_CONSTRUCTOR · a35afb83
      Christoph Lameter 提交于
      SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it.
      Signed-off-by: NChristoph Lameter <clameter@sgi.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      Cc: Steven French <sfrench@us.ibm.com>
      Cc: Michael Halcrow <mhalcrow@us.ibm.com>
      Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
      Cc: Miklos Szeredi <miklos@szeredi.hu>
      Cc: Steven Whitehouse <swhiteho@redhat.com>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Cc: David Woodhouse <dwmw2@infradead.org>
      Cc: Dave Kleikamp <shaggy@austin.ibm.com>
      Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
      Cc: "J. Bruce Fields" <bfields@fieldses.org>
      Cc: Anton Altaparmakov <aia21@cantab.net>
      Cc: Mark Fasheh <mark.fasheh@oracle.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Jan Kara <jack@ucw.cz>
      Cc: David Chinner <dgc@sgi.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a35afb83
  7. 08 5月, 2007 1 次提交
    • C
      slab allocators: Remove SLAB_DEBUG_INITIAL flag · 50953fe9
      Christoph Lameter 提交于
      I have never seen a use of SLAB_DEBUG_INITIAL.  It is only supported by
      SLAB.
      
      I think its purpose was to have a callback after an object has been freed
      to verify that the state is the constructor state again?  The callback is
      performed before each freeing of an object.
      
      I would think that it is much easier to check the object state manually
      before the free.  That also places the check near the code object
      manipulation of the object.
      
      Also the SLAB_DEBUG_INITIAL callback is only performed if the kernel was
      compiled with SLAB debugging on.  If there would be code in a constructor
      handling SLAB_DEBUG_INITIAL then it would have to be conditional on
      SLAB_DEBUG otherwise it would just be dead code.  But there is no such code
      in the kernel.  I think SLUB_DEBUG_INITIAL is too problematic to make real
      use of, difficult to understand and there are easier ways to accomplish the
      same effect (i.e.  add debug code before kfree).
      
      There is a related flag SLAB_CTOR_VERIFY that is frequently checked to be
      clear in fs inode caches.  Remove the pointless checks (they would even be
      pointless without removeal of SLAB_DEBUG_INITIAL) from the fs constructors.
      
      This is the last slab flag that SLUB did not support.  Remove the check for
      unimplemented flags from SLUB.
      Signed-off-by: NChristoph Lameter <clameter@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      50953fe9
  8. 21 2月, 2007 1 次提交
  9. 10 2月, 2007 5 次提交
  10. 08 12月, 2006 1 次提交
  11. 11 11月, 2006 1 次提交
  12. 28 9月, 2006 1 次提交
    • D
      [XFS] Really fix use after free in xfs_iunpin. · f273ab84
      David Chinner 提交于
      The previous attempts to fix the linux inode use-after-free in xfs_iunpin
      simply made the problem harder to hit. We actually need complete exclusion
      between xfs_reclaim and xfs_iunpin, as well as ensuring that the i_flags
      are consistent during both of these functions. Introduce a new spinlock
      for exclusion and the i_flags, and fix up xfs_iunpin to use igrab before
      marking the inode dirty.
      
      SGI-PV: 952967
      SGI-Modid: xfs-linux-melb:xfs-kern:26964a
      Signed-off-by: NDavid Chinner <dgc@sgi.com>
      Signed-off-by: NTim Shimmin <tes@sgi.com>
      f273ab84
  13. 27 9月, 2006 1 次提交
  14. 28 7月, 2006 1 次提交
  15. 23 6月, 2006 3 次提交
    • D
      [PATCH] XFS: Use the dentry passed to statfs() to limit the scope of the results · d6938d1b
      David Howells 提交于
      Enable XFS to limit the statfs() results to the project quota covering the
      dentry used as a base for call.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NNathan Scott <nathans@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d6938d1b
    • D
      [PATCH] VFS: Permit filesystem to perform statfs with a known root dentry · 726c3342
      David Howells 提交于
      Give the statfs superblock operation a dentry pointer rather than a superblock
      pointer.
      
      This complements the get_sb() patch.  That reduced the significance of
      sb->s_root, allowing NFS to place a fake root there.  However, NFS does
      require a dentry to use as a target for the statfs operation.  This permits
      the root in the vfsmount to be used instead.
      
      linux/mount.h has been added where necessary to make allyesconfig build
      successfully.
      
      Interest has also been expressed for use with the FUSE and XFS filesystems.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
      Cc: Nathan Scott <nathans@sgi.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      726c3342
    • D
      [PATCH] VFS: Permit filesystem to override root dentry on mount · 454e2398
      David Howells 提交于
      Extend the get_sb() filesystem operation to take an extra argument that
      permits the VFS to pass in the target vfsmount that defines the mountpoint.
      
      The filesystem is then required to manually set the superblock and root dentry
      pointers.  For most filesystems, this should be done with simple_set_mnt()
      which will set the superblock pointer and then set the root dentry to the
      superblock's s_root (as per the old default behaviour).
      
      The get_sb() op now returns an integer as there's now no need to return the
      superblock pointer.
      
      This patch permits a superblock to be implicitly shared amongst several mount
      points, such as can be done with NFS to avoid potential inode aliasing.  In
      such a case, simple_set_mnt() would not be called, and instead the mnt_root
      and mnt_sb would be set directly.
      
      The patch also makes the following changes:
      
       (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
           pointer argument and return an integer, so most filesystems have to change
           very little.
      
       (*) If one of the convenience function is not used, then get_sb() should
           normally call simple_set_mnt() to instantiate the vfsmount. This will
           always return 0, and so can be tail-called from get_sb().
      
       (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
           dcache upon superblock destruction rather than shrink_dcache_anon().
      
           This is required because the superblock may now have multiple trees that
           aren't actually bound to s_root, but that still need to be cleaned up. The
           currently called functions assume that the whole tree is rooted at s_root,
           and that anonymous dentries are not the roots of trees which results in
           dentries being left unculled.
      
           However, with the way NFS superblock sharing are currently set to be
           implemented, these assumptions are violated: the root of the filesystem is
           simply a dummy dentry and inode (the real inode for '/' may well be
           inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
           with child trees.
      
           [*] Anonymous until discovered from another tree.
      
       (*) The documentation has been adjusted, including the additional bit of
           changing ext2_* into foo_* in the documentation.
      
      [akpm@osdl.org: convert ipath_fs, do other stuff]
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
      Cc: Nathan Scott <nathans@sgi.com>
      Cc: Roland Dreier <rolandd@cisco.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      454e2398
  16. 20 6月, 2006 1 次提交
  17. 19 6月, 2006 1 次提交
  18. 09 6月, 2006 2 次提交
  19. 31 3月, 2006 1 次提交
  20. 27 3月, 2006 1 次提交
  21. 22 3月, 2006 1 次提交
  22. 17 3月, 2006 1 次提交