linux_dsm_epyc7002/arch/x86
Suresh Siddha 0280f7c416 x86, x2apic: cleanup the IO-APIC level migration with interrupt-remapping
Impact: simplification

In the current code, for level triggered migration, we need to modify the
io-apic RTE with the update vector information, along with modifying interrupt
remapping table entry(IRTE) with vector and destination. This is to ensure that
remote IRR bit inthe IOAPIC RTE gets cleared when the cpu does EOI.

With this patch, for level triggered, we eliminate the io-apic RTE modification
(with the updated vector information), by using a virtual vector (io-apic pin
number).  Real vector that is used for interrupting cpu will be coming from
the interrupt-remapping table entry. Trigger mode in the IRTE will always be
edge, and the actual level or edge trigger will be setup in the IO-APIC RTE.
So a level triggered interrupt will appear as an edge to the local apic
cpu but still as level to the IO-APIC.

With this change, level irq migration can be done by simply modifying
the interrupt-remapping table entry with out changing the io-apic RTE.
And as the interrupt appears as edge at the cpu, in addition to do the
local apic EOI, we need to do IO-APIC directed EOI to clear the remote
IRR bit in  the IO-APIC RTE.

This simplies the irq migration in the presence of interrupt-remapping.

Idea-by: Rajesh Sankaran <rajesh.sankaran@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17 15:44:27 -07:00
..
boot x86: use targets in the boot Makefile instead of CLEAN_FILES 2009-03-12 13:43:14 -07:00
configs Merge branches 'x86/apic', 'x86/defconfig', 'x86/memtest', 'x86/mm' and 'linus' into x86/core 2009-02-26 06:31:32 +01:00
crypto crypto: crc32c-intel - Switch to shash 2008-12-25 11:01:37 +11:00
ia32 x86: ia32_signal: introduce {get|set}_user_seg() 2009-02-22 17:54:47 +01:00
include/asm x86, x2apic: cleanup the IO-APIC level migration with interrupt-remapping 2009-03-17 15:44:27 -07:00
kernel x86, x2apic: cleanup the IO-APIC level migration with interrupt-remapping 2009-03-17 15:44:27 -07:00
kvm KVM: VMX: Flush volatile msrs before emulating rdmsr 2009-02-15 02:47:39 +02:00
lguest Merge branches 'x86/cleanups', 'x86/kexec', 'x86/mce2' and 'linus' into x86/core 2009-03-11 10:49:15 +01:00
lib x86: memcpy, clean up 2009-03-12 12:21:17 +01:00
math-emu Merge branch 'linus' into core/percpu 2009-03-11 10:29:28 +01:00
mm Merge branches 'x86/apic', 'x86/asm', 'x86/cleanups', 'x86/debug', 'x86/kconfig', 'x86/mm', 'x86/ptrace', 'x86/setup' and 'x86/urgent'; commit 'v2.6.29-rc8' into x86/core 2009-03-14 16:25:40 +01:00
oprofile x86: oprofile: don't set counter width from cpuid on Core2 2009-03-03 12:04:22 +01:00
pci x86: move a few device initialization objects into .devinit.rodata 2009-03-12 13:12:19 +01:00
power x86: use _types.h headers in asm where available 2009-02-13 11:35:01 -08:00
vdso x86, mm: rename TASK_SIZE64 => TASK_SIZE_MAX 2009-02-21 00:09:44 +01:00
video
xen Merge branch 'x86/core' into core/percpu 2009-03-04 02:29:19 +01:00
Kconfig Merge branches 'x86/apic', 'x86/asm', 'x86/cleanups', 'x86/debug', 'x86/kconfig', 'x86/mm', 'x86/ptrace', 'x86/setup' and 'x86/urgent'; commit 'v2.6.29-rc8' into x86/core 2009-03-14 16:25:40 +01:00
Kconfig.cpu Merge branch 'x86/urgent' into core/percpu 2009-02-10 00:41:02 +01:00
Kconfig.debug Merge branch 'linus' into x86/apic 2009-02-22 20:05:19 +01:00
Makefile x86: use targets in the boot Makefile instead of CLEAN_FILES 2009-03-12 13:43:14 -07:00
Makefile_32.cpu x86: merge winchip-2 and winchip-2a cpu choices 2008-10-13 10:22:48 +02:00