linux/arch
Suresh Siddha 5231a68614 x86: Remove local_irq_enable()/local_irq_disable() in fixup_irqs()
To ensure that we handle all the pending interrupts (destined
for this cpu that is going down) in the interrupt subsystem
before the cpu goes offline, fixup_irqs() does:

	local_irq_enable();
	mdelay(1);
	local_irq_disable();

Enabling interrupts is not a good thing as this cpu is already
offline. So this patch replaces that logic with,

	mdelay(1);
	check APIC_IRR bits
	Retrigger the irq at the new destination if any interrupt has arrived
	via IPI.

For IO-APIC level triggered interrupts, this retrigger IPI will
appear as an edge interrupt. ack_apic_level() will detect this
condition and IO-APIC RTE's remoteIRR is cleared using directed
EOI(using IO-APIC EOI register) on Intel platforms and for
others it uses the existing mask+edge logic followed by
unmask+level.

We can also remove mdelay() and then send spuriuous interrupts
to new cpu targets for all the irqs that were handled previously
by this cpu that is going offline. While it works, I have seen
spurious interrupt messages (nothing wrong but still annoying
messages during cpu offline, which can be seen during
suspend/resume etc)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Gary Hade <garyhade@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <20091026230002.043281924@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-02 15:56:37 +01:00
..
alpha alpha: Fix duplicate <asm/thread_info.h> include 2009-09-27 14:46:05 -07:00
arm ARM: force dcache flush if dcache_dirty bit set 2009-10-12 17:52:26 +01:00
avr32 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next 2009-09-23 15:37:02 -07:00
blackfin headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
cris const: constify remaining file_operations 2009-10-01 16:11:11 -07:00
frv FRV: Flash mappings for the MB93090-MB00 motherboard 2009-09-24 17:18:38 -07:00
h8300 h8300: Cleanup linker script using new linker script macros. 2009-09-24 17:16:22 -07:00
ia64 const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
m32r headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
m68k revert "m68k: convert to asm-generic/hardirq.h" 2009-10-01 16:11:11 -07:00
m68knommu m68knommu: fix rename of pt_regs offset defines breakage 2009-09-30 10:06:07 +10:00
microblaze microblaze: Clear sticky FSR register after saving it to func parametr 2009-10-05 11:37:47 +02:00
mips MIPS: Avoid spurious make includecheck message 2009-09-30 21:47:02 +02:00
mn10300 mn10300: fix kernel build failures when using gcc-4.x 2009-10-01 16:11:12 -07:00
parisc parisc: Fix linker script breakage. 2009-09-28 00:25:07 -04:00
powerpc const: constify remaining file_operations 2009-10-01 16:11:11 -07:00
s390 [S390] Add EX_TABLE for addressing exception in usercopy functions. 2009-10-06 10:35:10 +02:00
score Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next 2009-09-23 15:37:02 -07:00
sh sh: Don't allocate smaller sized mappings on every iteration 2009-10-09 11:26:35 +09:00
sparc Merge branch 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-10-08 12:05:50 -07:00
um headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
x86 x86: Remove local_irq_enable()/local_irq_disable() in fixup_irqs() 2009-11-02 15:56:37 +01:00
xtensa headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
.gitignore
Kconfig oprofile: fix oprofile regression: select RING_BUFFER_ALLOW_SWAP 2009-09-17 15:53:42 -04:00