Eric Lee / smarc-fsl-linux-kernel

01 Nov, 2011

1 commit

20 Mar, 2011

1 commit

30 Mar, 2010

1 commit

  • 5a0e3ad6a   include cleanup: Update gfp.h and slab.h includes to prepare for breaking implic… ... Browse Code »

    …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
     

19 Jun, 2009

1 commit

02 May, 2007

1 commit

  • 9c1600eda   i2c: Add i2c_board_info and i2c_new_device() ... Browse Code »

    This provides partial support for new-style I2C driver binding. It builds
    on "struct i2c_board_info" declarations that identify I2C devices on a given
    board. This is needed on systems with I2C devices that can't be fully probed
    and/or autoconfigured, such as many embedded Linux configurations where the
    way a given I2C device is wired may affect how it must be used.

    There are two models for declaring such devices:

    * LATE -- using a public function i2c_new_device(). This lets modules
    declare I2C devices found *AFTER* a given I2C adapter becomes available.

    For example, a PCI card could create adapters giving access to utility
    chips on that card, and this would be used to associate those chips with
    those adapters.

    * EARLY -- from arch_initcall() level code, using a non-exported function
    i2c_register_board_info(). This copies the declarations *BEFORE* such
    an i2c_adapter becomes available, arranging that i2c_new_device() will
    be called later when i2c-core registers the relevant i2c_adapter.

    For example, arch/.../.../board-*.c files would declare the I2C devices
    along with their platform data, and I2C devices would behave much like
    PNPACPI devices. (That is, both enumerate from board-specific tables.)

    To match the exported i2c_new_device(), the previously-private function
    i2c_unregister_device() is now exported.

    Pending later patches using these new APIs, this is effectively a NOP.

    Signed-off-by: David Brownell
    Signed-off-by: Jean Delvare

    David Brownell