Eric Lee / smarc-ti-linux-kernel

08 Oct, 2006

1 commit

05 Oct, 2006

1 commit

  • 7d12e780e   IRQ: Maintain regs pointer globally rather than passing to IRQ handlers ... Browse Code »

    Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
    of passing regs around manually through all ~1800 interrupt handlers in the
    Linux kernel.

    The regs pointer is used in few places, but it potentially costs both stack
    space and code to pass it around. On the FRV arch, removing the regs parameter
    from all the genirq function results in a 20% speed up of the IRQ exit path
    (ie: from leaving timer_interrupt() to leaving do_IRQ()).

    Where appropriate, an arch may override the generic storage facility and do
    something different with the variable. On FRV, for instance, the address is
    maintained in GR28 at all times inside the kernel as part of general exception
    handling.

    Having looked over the code, it appears that the parameter may be handed down
    through up to twenty or so layers of functions. Consider a USB character
    device attached to a USB hub, attached to a USB controller that posts its
    interrupts through a cascaded auxiliary interrupt controller. A character
    device driver may want to pass regs to the sysrq handler through the input
    layer which adds another few layers of parameter passing.

    I've build this code with allyesconfig for x86_64 and i386. I've runtested the
    main part of the code on FRV and i386, though I can't test most of the drivers.
    I've also done partial conversion for powerpc and MIPS - these at least compile
    with minimal configurations.

    This will affect all archs. Mostly the changes should be relatively easy.
    Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

    struct pt_regs *old_regs = set_irq_regs(regs);

    And put the old one back at the end:

    set_irq_regs(old_regs);

    Don't pass regs through to generic_handle_irq() or __do_IRQ().

    In timer_interrupt(), this sort of change will be necessary:

    - update_process_times(user_mode(regs));
    - profile_tick(CPU_PROFILING, regs);
    + update_process_times(user_mode(get_irq_regs()));
    + profile_tick(CPU_PROFILING);

    I'd like to move update_process_times()'s use of get_irq_regs() into itself,
    except that i386, alone of the archs, uses something other than user_mode().

    Some notes on the interrupt handling in the drivers:

    (*) input_dev() is now gone entirely. The regs pointer is no longer stored in
    the input_dev struct.

    (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
    something different depending on whether it's been supplied with a regs
    pointer or not.

    (*) Various IRQ handler function pointers have been moved to type
    irq_handler_t.

    Signed-Off-By: David Howells
    (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

    David Howells
     

02 Oct, 2006

1 commit

  • b68e31d0e   [PATCH] const struct tty_operations ... Browse Code »

    As part of an SMP cleanliness pass over UML, I consted a bunch of
    structures in order to not have to document their locking. One of these
    structures was a struct tty_operations. In order to const it in UML
    without introducing compiler complaints, the declaration of
    tty_set_operations needs to be changed, and then all of its callers need to
    be fixed.

    This patch declares all struct tty_operations in the tree as const. In all
    cases, they are static and used only as input to tty_set_operations. As an
    extra check, I ran an i386 allyesconfig build which produced no extra
    warnings.

    53 drivers are affected. I checked the history of a bunch of them, and in
    most cases, there have been only a handful of maintenance changes in the
    last six months. serial_core.c was the busiest one that I looked at.

    Signed-off-by: Jeff Dike
    Acked-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jeff Dike
     

03 Jul, 2006

1 commit

01 Jul, 2006

1 commit

27 Jun, 2006

2 commits

23 Mar, 2006

1 commit

  • 41c28ff16   [PATCH] kill _INLINE_ ... Browse Code »

    This patch removes all occurances of _INLINE_ in the kernel.

    With the exception of tty_flip.h, I've simply removed the inline's since
    gcc should know best which functions to be inlined.

    Signed-off-by: Adrian Bunk
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Adrian Bunk
     

08 Feb, 2006

1 commit

18 Nov, 2005

1 commit

08 Nov, 2005

1 commit

30 Oct, 2005

4 commits

13 Sep, 2005

1 commit

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »
    212

    Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds