31 Mar, 2011

1 commit


15 Sep, 2010

1 commit

  • The usage of the BKL in the OSS sound drivers is
    trivial, and each of them only locks against itself,
    so it can be turned into per-driver mutexes.

    This is the script that was used for the conversion:

    file=$1
    name=$2
    if grep -q lock_kernel ${file} ; then
    if grep -q 'include.*linux.mutex.h' ${file} ; then
    sed -i '/include.*/d' ${file}
    else
    sed -i 's/include.*.*$/include /g' ${file}
    fi
    sed -i ${file} \
    -e "/^#include.*linux.mutex.h/,$ {
    1,/^\(static\|int\|long\)/ {
    /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);

    } }" \
    -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
    -e '/[ ]*cycle_kernel_lock();/d'
    else
    sed -i -e '/include.*\/d' ${file} \
    -e '/cycle_kernel_lock()/d'
    fi

    Signed-off-by: Arnd Bergmann
    Signed-off-by: Takashi Iwai

    Arnd Bergmann
     

13 Jul, 2010

1 commit


12 Jul, 2010

1 commit

  • This moves the lock_kernel() call from soundcore_open
    to the individual OSS device drivers, where we can deal
    with it one driver at a time if needed, or just kill
    off the drivers.

    All core components in ALSA already provide
    adequate locking in their open()-functions
    and do not require the big kernel lock, so
    there is no need to add the BKL there.

    Signed-off-by: Arnd Bergmann
    Signed-off-by: Takashi Iwai

    Arnd Bergmann
     

21 Sep, 2009

1 commit


16 Mar, 2009

1 commit

  • Traditionally, changes to struct file->f_flags have been done under BKL
    protection, or with no protection at all. This patch causes all f_flags
    changes after file open/creation time to be done under protection of
    f_lock. This allows the removal of some BKL usage and fixes a number of
    longstanding (if microscopic) races.

    Reviewed-by: Christoph Hellwig
    Cc: Al Viro
    Signed-off-by: Jonathan Corbet

    Jonathan Corbet
     

21 Oct, 2008

1 commit


09 Feb, 2008

1 commit


09 May, 2007

1 commit


15 Feb, 2007

1 commit


13 Feb, 2007

1 commit


05 Oct, 2006

1 commit

  • 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
     

01 Oct, 2006

1 commit


26 Mar, 2006

1 commit

  • MODULE_PARM was actually breaking: recent gcc version optimize them out as
    unused. It's time to replace the last users, which are generally in the
    most unloved drivers anyway.

    Signed-off-by: Rusty Russell
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Rusty Russell
     

23 Mar, 2006

1 commit

  • Semaphore to mutex conversion.

    The conversion was generated via scripts, and the result was validated
    automatically via a script as well.

    Signed-off-by: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ingo Molnar
     

17 Apr, 2005

1 commit

  • 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