Eric Lee / smarc-fsl-linux-kernel

11 Oct, 2007

2 commits

18 Jul, 2007

1 commit

11 Jul, 2007

1 commit

09 May, 2007

1 commit

26 Apr, 2007

2 commits

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
     

14 Sep, 2006

2 commits

20 Aug, 2006

1 commit

06 Jul, 2006

2 commits

03 Jul, 2006

1 commit

01 Jul, 2006

1 commit

27 Jun, 2006

1 commit

  • 1f1bd5fc3   [netdrvr] Remove long-unused bits from Becker template drivers ... Browse Code »

    Symbols such as PCI_USES_IO, PCI_ADDR0, etc. originated from Donald
    Becker's net driver template, but have been long unused. Remove.

    In a few drivers, this allows the further eliminate of the pci_flags (or
    just plain flags) member in the template driver probe structure.

    Most of this logic is simply open-coded in most drivers, since it never
    changes.

    Made a few other cleanups while I was in there, too:
    * constify, __devinitdata several PCI ID tables
    * replace table terminating entries such as "{0,}," and "{NULL},"
    with a more-clean "{ }".

    Signed-off-by: Jeff Garzik

    Jeff Garzik
     

04 Mar, 2006

1 commit

19 Aug, 2005

1 commit

29 Jun, 2005

1 commit

  • 689be4394   [NET]: Remove gratuitous use of skb->tail in network drivers. ... Browse Code »

    Many drivers use skb->tail unnecessarily.

    In these situations, the code roughly looks like:

    dev = dev_alloc_skb(...);

    [optional] skb_reserve(skb, ...);

    ... skb->tail ...

    But even if the skb_reserve() happens, skb->data equals
    skb->tail. So it doesn't make any sense to use anything
    other than skb->data in these cases.

    Another case was the s2io.c driver directly mucking with
    the skb->data and skb->tail pointers. It really just wanted
    to do an skb_reserve(), so that's what the code was changed
    to do instead.

    Another reason I'm making this change as it allows some SKB
    cleanups I have planned simpler to merge. In those cleanups,
    skb->head, skb->tail, and skb->end pointers are removed, and
    replaced with skb->head_room and skb->tail_room integers.

    Signed-off-by: David S. Miller
    Acked-by: Jeff Garzik

    David S. Miller
     

17 Apr, 2005

1 commit

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

    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