30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

11 Dec, 2009

1 commit


04 Dec, 2009

1 commit

  • That is "success", "unknown", "through", "performance", "[re|un]mapping"
    , "access", "default", "reasonable", "[con]currently", "temperature"
    , "channel", "[un]used", "application", "example","hierarchy", "therefore"
    , "[over|under]flow", "contiguous", "threshold", "enough" and others.

    Signed-off-by: André Goddard Rosa
    Signed-off-by: Jiri Kosina

    André Goddard Rosa
     

01 Dec, 2009

1 commit

  • Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
    ls_allocation would be GFP_KERNEL for userland lockspaces
    and GFP_NOFS for file system lockspaces.

    It was discovered that any lockspaces on the system can
    affect all others by triggering memory reclaim in the
    file system which could in turn call back into the dlm
    to acquire locks, deadlocking dlm threads that were
    shared by all lockspaces, like dlm_recv.

    Signed-off-by: David Teigland

    David Teigland
     

19 Jun, 2009

1 commit

  • Fix a regression from the original addition of nfs lock support
    586759f03e2e9031ac5589912a51a909ed53c30a. When a synchronous
    (non-nfs) plock completes, the waiting thread will wake up and
    free the op struct. This races with the user thread in
    dev_write() which goes on to read the op's callback field to
    check if the lock is async and needs a callback. This check
    can happen on the freed op. The fix is to note the callback
    value before the op can be freed.

    Signed-off-by: David Teigland

    David Teigland
     

22 Jan, 2009

2 commits

  • dlm_posix_get fills out the relevant fields in the file_lock before
    returning when there is a lock conflict, but doesn't clean out any of
    the other fields in the file_lock.

    When nfsd does a NFSv4 lockt call, it sets the fl_lmops to
    nfsd_posix_mng_ops before calling the lower fs. When the lock comes back
    after testing a lock on GFS2, it still has that field set. This confuses
    nfsd into thinking that the file_lock is a nfsd4 lock.

    Fix this by making DLM reinitialize the file_lock before copying the
    fields from the conflicting lock.

    Signed-off-by: Jeff Layton
    Signed-off-by: David Teigland

    Jeff Layton
     
  • We should use the original copy of the file_lock, fl, instead
    of the copy, flc in the lockd notify callback. The range in flc has
    been modified by posix_lock_file(), so it will not match a copy of the
    lock in lockd.

    Signed-off-by: David Teigland

    David Teigland
     

26 Jul, 2008

1 commit

  • Use a special error value FILE_LOCK_DEFERRED to mean that a locking
    operation returned asynchronously. This is returned by

    posix_lock_file() for sleeping locks to mean that the lock has been
    queued on the block list, and will be woken up when it might become
    available and needs to be retried (either fl_lmops->fl_notify() is
    called or fl_wait is woken up).

    f_op->lock() to mean either the above, or that the filesystem will
    call back with fl_lmops->fl_grant() when the result of the locking
    operation is known. The filesystem can do this for sleeping as well
    as non-sleeping locks.

    This is to make sure, that return values of -EAGAIN and -EINPROGRESS by
    filesystems are not mistaken to mean an asynchronous locking.

    This also makes error handling in fs/locks.c and lockd/svclock.c slightly
    cleaner.

    Signed-off-by: Miklos Szeredi
    Cc: Trond Myklebust
    Cc: "J. Bruce Fields"
    Cc: Matthew Wilcox
    Cc: David Teigland
    Cc: Christoph Hellwig
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Miklos Szeredi
     

20 May, 2008

1 commit


22 Apr, 2008

1 commit