Eric Lee / smarc-fsl-linux-kernel

10 May, 2007

1 commit

  • 2f4dfe206   Remove hardcoding of hard_smp_processor_id on UP systems ... Browse Code »

    With the advent of kdump, the assumption that the boot CPU when booting an UP
    kernel is always the CPU with a particular hardware ID (often 0) (usually
    referred to as BSP on some architectures) is not valid anymore. The reason
    being that the dump capture kernel boots on the crashed CPU (the CPU that
    invoked crash_kexec), which may be or may not be that particular CPU.

    Move definition of hard_smp_processor_id for the UP case to
    architecture-specific code ("asm/smp.h") where it belongs, so that each
    architecture can provide its own implementation.

    Signed-off-by: Fernando Luis Vazquez Cao
    Cc: "Luck, Tony"
    Acked-by: Andi Kleen
    Cc: "Eric W. Biederman"
    Cc: Vivek Goyal
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Fernando Luis Vazquez Cao
     

07 Feb, 2007

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
     

26 Apr, 2006

1 commit

27 Mar, 2006

1 commit

  • 4df20460a   [PATCH] powerpc: Allow non zero boot cpuids ... Browse Code »

    We currently have a hack to flip the boot cpu and its secondary thread
    to logical cpuid 0 and 1. This means the logical - physical mapping will
    differ depending on which cpu is boot cpu. This is most apparent on
    kexec, where we might kexec on any cpu and therefore change the mapping
    from boot to boot.

    The patch below does a first pass early on to work out the logical cpuid
    of the boot thread. We then fix up some paca structures to match.

    Ive also removed the boot_cpuid_phys variable for ppc64, to be
    consistent we use get_hard_smp_processor_id(boot_cpuid) everywhere.

    Signed-off-by: Anton Blanchard
    Signed-off-by: Paul Mackerras

    Anton Blanchard
     

07 Nov, 2005

1 commit

  • 2249ca9d6   powerpc: Various UP build fixes ... Browse Code »

    Mostly this involves adding #include , since that defines
    things like boot_cpuid[_phys] and [gs]et_hard_smp_processor_id, which
    are SMP-related but still needed on UP. This incorporates fixes
    posted by Olof Johansson and Heikki Lindholm.

    Signed-off-by: Paul Mackerras

    Paul Mackerras
     

05 Nov, 2005

1 commit