lkml.org 
[lkml]   [2004]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH] fix platform_rename_gsi related ia32 build breakage
    From
    Date
    On Thu, 2004-11-11 at 17:30, Linus Torvalds wrote:
    >
    > On Thu, 11 Nov 2004, Len Brown wrote:
    > >
    > > I used a function pointer here because the same kernel binary must
    > be
    > > able to run on an ES7000 or a non-ES7000, so the compile-time inline
    > > idiom doesn't work.
    >
    > Sure it does. Do something like this in a header file
    >
    > static inline int translate_irq_number(...)
    > {
    > #ifdef CONFIG_ACPI_BOOT
    > return fn_ptr_xxx();
    > #else
    > return irq;
    > #endif
    > }

    sure, we could add a wrapper for the wrapper,
    but the ifdefs are already gone without doing this --
    platform_rename_gsi is present with or without ACPI.

    I suppose I could shrink the kernel by 4-bytes by compiling out the
    function pointer when IO_APIC is not defined. I'll be happy to optimize
    for that case if you think it justifies the code; though if I were
    optimizing for that case, this probably isn't where I'd start.

    > which means that yes, it uses the function pointer when it is
    > meaningful, but if there is no point, the code just goes away.
    >
    > > If you read this far and have suggestions for a more descriptive
    > name than platform_rename_gsi(), just let me know.
    >
    > At _least_ write out what the hell "gsi" is.
    >
    > TLA's are bad. "gsi" apparently isn't the Geological Survey of
    > Ireland, but that's all I can tell from google.

    The _gsi in platform_rename_gsi was consistent with the surrounding use
    in the ACPI case. I decided to re-use the same funtion for the MPS case
    for simplicity, even though io_apic.c uses _irq. If you like, I can add
    a synonym using an inline for _irq, but I thought we were moving away
    from using _irq, not towards it.

    GSI = Global System Interrupt
    IRQ = overused so much it means nothing at all

    While this fact may not win you over as a fan, GSI is actually
    consistent with the language in the ACPI spec. I don't know if that is
    where Bjorn came up with the name, but I do think it was a positive
    change. The reason is that "global" actually means something -- and it
    still has the same semantics no matter if your machine passes around cpu
    interrupt vectors or if it passes around pin numbers.

    cheers,
    -Len


    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 14:07    [W:0.026 / U:274.680 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site