[PATCH RFC 02/13] x86: Add a Kconfig option for posted MSI

[Jacob Pan]

This option will be used to support delivering MSIs as posted
interrupts. Interrupt remapping is required.

Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
---
 arch/x86/Kconfig | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 66bfabae8814..f16882ddb390 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -463,6 +463,16 @@ config X86_X2APIC
 
 	  If you don't know what to do here, say N.
 
+config X86_POSTED_MSI
+	bool "Enable MSI and MSI-x delivery by posted interrupts"
+	depends on X86_X2APIC && X86_64 && IRQ_REMAP
+	help
+	  This enables MSIs that are under IRQ remapping to be delivered as posted
+	  interrupts to the host kernel. IRQ throughput can potentially be improved
+	  by coalescing CPU notifications during high frequency IRQ bursts.
+
+	  If you don't know what to do here, say N.
+
 config X86_MPPARSE
 	bool "Enable MPS table" if ACPI
 	default y
-- 
2.25.1