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From: Jacob Pan <jacob.jun.pan@linux.intel.com>
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Cc: Paul Luse <paul.e.luse@intel.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Jens Axboe <axboe@kernel.dk>,
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	"Bjorn Helgaas" <helgaas@kernel.org>,
	guang.zeng@intel.com,
	robert.hoo.linux@gmail.com,
	Jacob Pan <jacob.jun.pan@linux.intel.com>
Subject: [PATCH v2 05/13] x86/irq: Reserve a per CPU IDT vector for posted MSIs
Date: Fri,  5 Apr 2024 15:31:02 -0700
Message-Id: <20240405223110.1609888-6-jacob.jun.pan@linux.intel.com>
In-Reply-To: <20240405223110.1609888-1-jacob.jun.pan@linux.intel.com>
References: <20240405223110.1609888-1-jacob.jun.pan@linux.intel.com>
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When posted MSI is enabled, all device MSIs are multiplexed into a single
notification vector. MSI handlers will be de-multiplexed at run-time by
system software without IDT delivery.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>

---
v2:
 - Add missing CONFIG_ in #ifdef
 - Extend changes to x86 tools
---
 arch/x86/include/asm/irq_vectors.h       | 9 ++++++++-
 tools/arch/x86/include/asm/irq_vectors.h | 9 ++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index d18bfb238f66..1ee00be8218d 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -97,9 +97,16 @@
 
 #define LOCAL_TIMER_VECTOR		0xec
 
+/*
+ * Posted interrupt notification vector for all device MSIs delivered to
+ * the host kernel.
+ */
+#define POSTED_MSI_NOTIFICATION_VECTOR	0xeb
 #define NR_VECTORS			 256
 
-#ifdef CONFIG_X86_LOCAL_APIC
+#ifdef CONFIG_X86_POSTED_MSI
+#define FIRST_SYSTEM_VECTOR		POSTED_MSI_NOTIFICATION_VECTOR
+#elif defined(CONFIG_X86_LOCAL_APIC)
 #define FIRST_SYSTEM_VECTOR		LOCAL_TIMER_VECTOR
 #else
 #define FIRST_SYSTEM_VECTOR		NR_VECTORS
diff --git a/tools/arch/x86/include/asm/irq_vectors.h b/tools/arch/x86/include/asm/irq_vectors.h
index 3f73ac3ed3a0..989816ca7c9e 100644
--- a/tools/arch/x86/include/asm/irq_vectors.h
+++ b/tools/arch/x86/include/asm/irq_vectors.h
@@ -99,9 +99,16 @@
 
 #define LOCAL_TIMER_VECTOR		0xec
 
+/*
+ * Posted interrupt notification vector for all device MSIs delivered to
+ * the host kernel.
+ */
+#define POSTED_MSI_NOTIFICATION_VECTOR	0xeb
 #define NR_VECTORS			 256
 
-#ifdef CONFIG_X86_LOCAL_APIC
+#ifdef CONFIG_X86_POSTED_MSI
+#define FIRST_SYSTEM_VECTOR		POSTED_MSI_NOTIFICATION_VECTOR
+#elif defined(CONFIG_X86_LOCAL_APIC)
 #define FIRST_SYSTEM_VECTOR		LOCAL_TIMER_VECTOR
 #else
 #define FIRST_SYSTEM_VECTOR		NR_VECTORS
-- 
2.25.1