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  1. 26 11月, 2013 22 次提交
  3. 15 11月, 2013 1 次提交
  5. 14 11月, 2013 3 次提交
    • T
      preempt: Make PREEMPT_ACTIVE generic · 00d1a39e
      由 Thomas Gleixner 提交于 
      No point in having this bit defined by architecture.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130917183629.090698799@linutronix.de
      00d1a39e
    • T
      hardirq: Make hardirq bits generic · 54197e43
      由 Thomas Gleixner 提交于 
      There is no reason for per arch hardirq bits. Make them all generic
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130917183628.534494408@linutronix.de
      54197e43
    • T
      m68k: Simplify low level interrupt handling code · 09f90f66
      由 Thomas Gleixner 提交于 
      The low level interrupt entry code of m68k contains the following:

    add_preempt_count(HARDIRQ_OFFSET);

    do_IRQ();
	irq_enter();
	    add_preempt_count(HARDIRQ_OFFSET);
	handle_interrupt();    
	irq_exit();    
	    sub_preempt_count(HARDIRQ_OFFSET);
	    if (in_interrupt())
       	       return; <---- On m68k always taken!
	    if (local_softirq_pending())
       	       do_softirq();

    sub_preempt_count(HARDIRQ_OFFSET);
    if (in_hardirq())
       return;
    if (status_on_stack_has_interrupt_priority_mask > 0)
       return;
    if (local_softirq_pending())
       do_softirq();

    ret_from_exception:
	if (interrupted_context_is_kernel)
	   return:
	....

I tried to find a proper explanation for this, but the changelog is
sparse and there are no mails explaining it further. But obviously
this relates to the interrupt priority levels of the m68k and tries to
be extra clever with nested interrupts. Though this cleverness just
adds code bloat to the interrupt hotpath.

For the common case of non nested interrupts the code runs through two
extra conditionals to the only important one, which checks whether the
return is to kernel or user space.

For the nested case the checks for in_hardirq() and the priority mask
value on stack catch only the case where the nested interrupt happens
inside the hard irq context of the first interrupt. If the nested
interrupt happens while the first interrupt handles soft interrupts,
then these extra checks buy nothing. The nested interrupt will fall
through to the final kernel/user space return check at
ret_from_exception.

Changing the code flow in the following way:

    do_IRQ();
	irq_enter();
	    add_preempt_count(HARDIRQ_OFFSET);
	handle_interrupt();    
	irq_exit();    
	    sub_preempt_count(HARDIRQ_OFFSET);
	    if (in_interrupt())
       	       return;
	    if (local_softirq_pending())
       	       do_softirq();

    ret_from_exception:
	if (interrupted_context_is_kernel)
	   return:

makes the region protected by the hardirq count slightly smaller and
the softirq handling is invoked with a minimal deeper stack. But
otherwise it's completely functional equivalent and saves 104 bytes of
text in arch/m68k/kernel/entry.o.

This modification allows us further to get rid of the limitations
which m68k puts on the preempt_count layout, so we can make the
preempt count bits completely generic.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NMichael Schmitz <schmitz@biophys.uni-duesseldorf.de>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: Linux/m68k <linux-m68k@vger.kernel.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1311112052360.30673@ionos.tec.linutronix.de
      09f90f66
  7. 24 10月, 2013 1 次提交
  9. 26 9月, 2013 1 次提交
  11. 25 9月, 2013 1 次提交
  13. 13 9月, 2013 2 次提交
  15. 10 9月, 2013 1 次提交
  17. 26 8月, 2013 5 次提交
  19. 23 8月, 2013 2 次提交
    • G
      m68k/atari: ARAnyM - Always use physical addresses in NatFeat calls · 55490050
      由 Geert Uytterhoeven 提交于 
      Pointers passed to ARAnyM NatFeat calls should be physical addresses,
not virtual addresses. This worked before because on Atari, physical and
virtual kernel addresses are the same, as long as normal kernel memory
is concerned.

Correct the few remaining places where virtual addresses were used.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
      55490050
    • G
      m68k: Ignore disabled HSYNC interrupt on Atari for irqs_disabled() · 3c776a07
      由 Geert Uytterhoeven 提交于 
      When running a multi-platform kernel on Atari, warning messages like
the following may be printed:

    WARNING: at /root/linux-3.10.1/init/main.c:698 do_one_initcall+0x12e/0x13a()
    initcall param_sysfs_init+0x0/0x1a4 returned with disabled interrupts

This is caused by the different definitions of ALLOWINT for Atari and
other platforms:

    #if defined(MACH_ATARI_ONLY)
    #define ALLOWINT        (~0x500)
    #else
    #define ALLOWINT        (~0x700)
    #endif

On Atari, we want to disable the high-frequency HSYNC interrupt:
  - On Atari-only kernels, this is handled completely through ALLOWINT,
  - On multi-platform kernels, this is handled by disabling the HSYNC
    interrupt from the interrupt handler.

However, as in the latter case arch_irqs_disabled_flags() didn't ignore the
disabling of the HSYNC interrupt, irqs_disabled() would detect false
positives.

Ignore the HSYNC interrupt when running on Atari to fix this.
For single-platform kernels this test is optimized away by the compiler.
Reported-by: NThorsten Glaser <tg@debian.org>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Tested-by: NThorsten Glaser <tg@debian.org>
      3c776a07
  21. 14 8月, 2013 1 次提交
    • F
      m68k: hardirq_count() only need preempt_mask.h · a703f9b7
      由 Frederic Weisbecker 提交于 
      The m68k irqflags implementation needs to check hardirq
context in some cases.

As it is a very low level header file, it's better to
include preempt_mask.h rather than hardirq.h when the
only purpose is to use irq context APIs. This way we
can avoid future header circular dependencies when
vtime.h will expand to use static keys.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      a703f9b7