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authorLinus Torvalds <torvalds@linux-foundation.org>2024-05-14 20:01:29 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2024-05-14 20:01:29 +0300
commit9776dd36095be19f5a0ad9f07a4fc221d2a0609a (patch)
treebd2bf5c11cf57fc187569670911a51f0b16f2796 /arch/x86
parent6bfd2d442af5c373042f196eef1915e1f6ac058a (diff)
parent6ecc2e7932fe8f132d3b671685f9995785f19e9a (diff)
downloadlinux-9776dd36095be19f5a0ad9f07a4fc221d2a0609a.tar.xz
Merge tag 'x86-irq-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 interrupt handling updates from Thomas Gleixner: "Add support for posted interrupts on bare metal. Posted interrupts is a virtualization feature which allows to inject interrupts directly into a guest without host interaction. The VT-d interrupt remapping hardware sets the bit which corresponds to the interrupt vector in a vector bitmap which is either used to inject the interrupt directly into the guest via a virtualized APIC or in case that the guest is scheduled out provides a host side notification interrupt which informs the host that an interrupt has been marked pending in the bitmap. This can be utilized on bare metal for scenarios where multiple devices, e.g. NVME storage, raise interrupts with a high frequency. In the default mode these interrupts are handles independently and therefore require a full roundtrip of interrupt entry/exit. Utilizing posted interrupts this roundtrip overhead can be avoided by coalescing these interrupt entries to a single entry for the posted interrupt notification. The notification interrupt then demultiplexes the pending bits in a memory based bitmap and invokes the corresponding device specific handlers. Depending on the usage scenario and device utilization throughput improvements between 10% and 130% have been measured. As this is only relevant for high end servers with multiple device queues per CPU attached and counterproductive for situations where interrupts are arriving at distinct times, the functionality is opt-in via a kernel command line parameter" * tag 'x86-irq-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Use existing helper for pending vector check iommu/vt-d: Enable posted mode for device MSIs iommu/vt-d: Make posted MSI an opt-in command line option x86/irq: Extend checks for pending vectors to posted interrupts x86/irq: Factor out common code for checking pending interrupts x86/irq: Install posted MSI notification handler x86/irq: Factor out handler invocation from common_interrupt() x86/irq: Set up per host CPU posted interrupt descriptors x86/irq: Reserve a per CPU IDT vector for posted MSIs x86/irq: Add a Kconfig option for posted MSI x86/irq: Remove bitfields in posted interrupt descriptor x86/irq: Unionize PID.PIR for 64bit access w/o casting KVM: VMX: Move posted interrupt descriptor out of VMX code
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/Kconfig11
-rw-r--r--arch/x86/entry/entry_fred.c2
-rw-r--r--arch/x86/include/asm/apic.h6
-rw-r--r--arch/x86/include/asm/hardirq.h6
-rw-r--r--arch/x86/include/asm/idtentry.h6
-rw-r--r--arch/x86/include/asm/irq_remapping.h7
-rw-r--r--arch/x86/include/asm/irq_vectors.h8
-rw-r--r--arch/x86/include/asm/posted_intr.h118
-rw-r--r--arch/x86/kernel/apic/vector.c5
-rw-r--r--arch/x86/kernel/cpu/common.c3
-rw-r--r--arch/x86/kernel/idt.c3
-rw-r--r--arch/x86/kernel/irq.c172
-rw-r--r--arch/x86/kvm/vmx/posted_intr.c4
-rw-r--r--arch/x86/kvm/vmx/posted_intr.h93
-rw-r--r--arch/x86/kvm/vmx/vmx.c3
-rw-r--r--arch/x86/kvm/vmx/vmx.h2
16 files changed, 335 insertions, 114 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 07e8817278a4..9d16fee6bdb8 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -466,6 +466,17 @@ 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_64 && IRQ_REMAP
+ help
+ This enables MSIs that are under interrupt remapping to be delivered as
+ posted interrupts to the host kernel. Interrupt throughput can
+ potentially be improved by coalescing CPU notifications during high
+ frequency bursts.
+
+ If you don't know what to do here, say N.
+
config X86_MPPARSE
bool "Enable MPS table" if ACPI
default y
diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c
index 89c1476fcdd9..f004a4dc74c2 100644
--- a/arch/x86/entry/entry_fred.c
+++ b/arch/x86/entry/entry_fred.c
@@ -117,6 +117,8 @@ static idtentry_t sysvec_table[NR_SYSTEM_VECTORS] __ro_after_init = {
SYSVEC(POSTED_INTR_VECTOR, kvm_posted_intr_ipi),
SYSVEC(POSTED_INTR_WAKEUP_VECTOR, kvm_posted_intr_wakeup_ipi),
SYSVEC(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi),
+
+ SYSVEC(POSTED_MSI_NOTIFICATION_VECTOR, posted_msi_notification),
};
static bool fred_setup_done __initdata;
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 839c58f95114..9327eb00e96d 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -14,6 +14,7 @@
#include <asm/msr.h>
#include <asm/hardirq.h>
#include <asm/io.h>
+#include <asm/posted_intr.h>
#define ARCH_APICTIMER_STOPS_ON_C3 1
@@ -500,6 +501,11 @@ static inline bool lapic_vector_set_in_irr(unsigned int vector)
return !!(irr & (1U << (vector % 32)));
}
+static inline bool is_vector_pending(unsigned int vector)
+{
+ return lapic_vector_set_in_irr(vector) || pi_pending_this_cpu(vector);
+}
+
/*
* Warm reset vector position:
*/
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index fbc7722b87d1..c67fa6ad098a 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -44,10 +44,16 @@ typedef struct {
unsigned int irq_hv_reenlightenment_count;
unsigned int hyperv_stimer0_count;
#endif
+#ifdef CONFIG_X86_POSTED_MSI
+ unsigned int posted_msi_notification_count;
+#endif
} ____cacheline_aligned irq_cpustat_t;
DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
+#ifdef CONFIG_X86_POSTED_MSI
+DECLARE_PER_CPU_ALIGNED(struct pi_desc, posted_msi_pi_desc);
+#endif
#define __ARCH_IRQ_STAT
#define inc_irq_stat(member) this_cpu_inc(irq_stat.member)
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index 749c7411d2f1..d4f24499b256 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -751,6 +751,12 @@ DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_NESTED_VECTOR, sysvec_kvm_posted_intr_nested
# define fred_sysvec_kvm_posted_intr_nested_ipi NULL
#endif
+# ifdef CONFIG_X86_POSTED_MSI
+DECLARE_IDTENTRY_SYSVEC(POSTED_MSI_NOTIFICATION_VECTOR, sysvec_posted_msi_notification);
+#else
+# define fred_sysvec_posted_msi_notification NULL
+# endif
+
#if IS_ENABLED(CONFIG_HYPERV)
DECLARE_IDTENTRY_SYSVEC(HYPERVISOR_CALLBACK_VECTOR, sysvec_hyperv_callback);
DECLARE_IDTENTRY_SYSVEC(HYPERV_REENLIGHTENMENT_VECTOR, sysvec_hyperv_reenlightenment);
diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h
index 7a2ed154a5e1..5036f13ab69f 100644
--- a/arch/x86/include/asm/irq_remapping.h
+++ b/arch/x86/include/asm/irq_remapping.h
@@ -50,6 +50,13 @@ static inline struct irq_domain *arch_get_ir_parent_domain(void)
return x86_vector_domain;
}
+extern bool enable_posted_msi;
+
+static inline bool posted_msi_supported(void)
+{
+ return enable_posted_msi && irq_remapping_cap(IRQ_POSTING_CAP);
+}
+
#else /* CONFIG_IRQ_REMAP */
static inline bool irq_remapping_cap(enum irq_remap_cap cap) { return 0; }
diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index d18bfb238f66..13aea8fc3d45 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -97,10 +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
-#define FIRST_SYSTEM_VECTOR LOCAL_TIMER_VECTOR
+#define FIRST_SYSTEM_VECTOR POSTED_MSI_NOTIFICATION_VECTOR
#else
#define FIRST_SYSTEM_VECTOR NR_VECTORS
#endif
diff --git a/arch/x86/include/asm/posted_intr.h b/arch/x86/include/asm/posted_intr.h
new file mode 100644
index 000000000000..de788b400fba
--- /dev/null
+++ b/arch/x86/include/asm/posted_intr.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _X86_POSTED_INTR_H
+#define _X86_POSTED_INTR_H
+#include <asm/irq_vectors.h>
+
+#define POSTED_INTR_ON 0
+#define POSTED_INTR_SN 1
+
+#define PID_TABLE_ENTRY_VALID 1
+
+/* Posted-Interrupt Descriptor */
+struct pi_desc {
+ union {
+ u32 pir[8]; /* Posted interrupt requested */
+ u64 pir64[4];
+ };
+ union {
+ struct {
+ u16 notifications; /* Suppress and outstanding bits */
+ u8 nv;
+ u8 rsvd_2;
+ u32 ndst;
+ };
+ u64 control;
+ };
+ u32 rsvd[6];
+} __aligned(64);
+
+static inline bool pi_test_and_set_on(struct pi_desc *pi_desc)
+{
+ return test_and_set_bit(POSTED_INTR_ON, (unsigned long *)&pi_desc->control);
+}
+
+static inline bool pi_test_and_clear_on(struct pi_desc *pi_desc)
+{
+ return test_and_clear_bit(POSTED_INTR_ON, (unsigned long *)&pi_desc->control);
+}
+
+static inline bool pi_test_and_clear_sn(struct pi_desc *pi_desc)
+{
+ return test_and_clear_bit(POSTED_INTR_SN, (unsigned long *)&pi_desc->control);
+}
+
+static inline bool pi_test_and_set_pir(int vector, struct pi_desc *pi_desc)
+{
+ return test_and_set_bit(vector, (unsigned long *)pi_desc->pir);
+}
+
+static inline bool pi_is_pir_empty(struct pi_desc *pi_desc)
+{
+ return bitmap_empty((unsigned long *)pi_desc->pir, NR_VECTORS);
+}
+
+static inline void pi_set_sn(struct pi_desc *pi_desc)
+{
+ set_bit(POSTED_INTR_SN, (unsigned long *)&pi_desc->control);
+}
+
+static inline void pi_set_on(struct pi_desc *pi_desc)
+{
+ set_bit(POSTED_INTR_ON, (unsigned long *)&pi_desc->control);
+}
+
+static inline void pi_clear_on(struct pi_desc *pi_desc)
+{
+ clear_bit(POSTED_INTR_ON, (unsigned long *)&pi_desc->control);
+}
+
+static inline void pi_clear_sn(struct pi_desc *pi_desc)
+{
+ clear_bit(POSTED_INTR_SN, (unsigned long *)&pi_desc->control);
+}
+
+static inline bool pi_test_on(struct pi_desc *pi_desc)
+{
+ return test_bit(POSTED_INTR_ON, (unsigned long *)&pi_desc->control);
+}
+
+static inline bool pi_test_sn(struct pi_desc *pi_desc)
+{
+ return test_bit(POSTED_INTR_SN, (unsigned long *)&pi_desc->control);
+}
+
+/* Non-atomic helpers */
+static inline void __pi_set_sn(struct pi_desc *pi_desc)
+{
+ pi_desc->notifications |= BIT(POSTED_INTR_SN);
+}
+
+static inline void __pi_clear_sn(struct pi_desc *pi_desc)
+{
+ pi_desc->notifications &= ~BIT(POSTED_INTR_SN);
+}
+
+#ifdef CONFIG_X86_POSTED_MSI
+/*
+ * Not all external vectors are subject to interrupt remapping, e.g. IOMMU's
+ * own interrupts. Here we do not distinguish them since those vector bits in
+ * PIR will always be zero.
+ */
+static inline bool pi_pending_this_cpu(unsigned int vector)
+{
+ struct pi_desc *pid = this_cpu_ptr(&posted_msi_pi_desc);
+
+ if (WARN_ON_ONCE(vector > NR_VECTORS || vector < FIRST_EXTERNAL_VECTOR))
+ return false;
+
+ return test_bit(vector, (unsigned long *)pid->pir);
+}
+
+extern void intel_posted_msi_init(void);
+#else
+static inline bool pi_pending_this_cpu(unsigned int vector) { return false; }
+
+static inline void intel_posted_msi_init(void) {};
+#endif /* X86_POSTED_MSI */
+
+#endif /* _X86_POSTED_INTR_H */
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 185738c72766..9eec52925fa3 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -965,7 +965,7 @@ static void __vector_cleanup(struct vector_cleanup *cl, bool check_irr)
lockdep_assert_held(&vector_lock);
hlist_for_each_entry_safe(apicd, tmp, &cl->head, clist) {
- unsigned int irr, vector = apicd->prev_vector;
+ unsigned int vector = apicd->prev_vector;
/*
* Paranoia: Check if the vector that needs to be cleaned
@@ -979,8 +979,7 @@ static void __vector_cleanup(struct vector_cleanup *cl, bool check_irr)
* fixup_irqs() was just called to scan IRR for set bits and
* forward them to new destination CPUs via IPIs.
*/
- irr = check_irr ? apic_read(APIC_IRR + (vector / 32 * 0x10)) : 0;
- if (irr & (1U << (vector % 32))) {
+ if (check_irr && is_vector_pending(vector)) {
pr_warn_once("Moved interrupt pending in old target APIC %u\n", apicd->irq);
rearm = true;
continue;
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index cdaa795a9371..2b170da84f97 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -68,6 +68,7 @@
#include <asm/traps.h>
#include <asm/sev.h>
#include <asm/tdx.h>
+#include <asm/posted_intr.h>
#include "cpu.h"
@@ -2222,6 +2223,8 @@ void cpu_init(void)
barrier();
x2apic_setup();
+
+ intel_posted_msi_init();
}
mmgrab(&init_mm);
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index fc37c8d83daf..f445bec516a0 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -163,6 +163,9 @@ static const __initconst struct idt_data apic_idts[] = {
# endif
INTG(SPURIOUS_APIC_VECTOR, asm_sysvec_spurious_apic_interrupt),
INTG(ERROR_APIC_VECTOR, asm_sysvec_error_interrupt),
+# ifdef CONFIG_X86_POSTED_MSI
+ INTG(POSTED_MSI_NOTIFICATION_VECTOR, asm_sysvec_posted_msi_notification),
+# endif
#endif
};
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 35fde0107901..385e3a5fc304 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -22,6 +22,8 @@
#include <asm/desc.h>
#include <asm/traps.h>
#include <asm/thermal.h>
+#include <asm/posted_intr.h>
+#include <asm/irq_remapping.h>
#define CREATE_TRACE_POINTS
#include <asm/trace/irq_vectors.h>
@@ -182,6 +184,13 @@ int arch_show_interrupts(struct seq_file *p, int prec)
irq_stats(j)->kvm_posted_intr_wakeup_ipis);
seq_puts(p, " Posted-interrupt wakeup event\n");
#endif
+#ifdef CONFIG_X86_POSTED_MSI
+ seq_printf(p, "%*s: ", prec, "PMN");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ",
+ irq_stats(j)->posted_msi_notification_count);
+ seq_puts(p, " Posted MSI notification event\n");
+#endif
return 0;
}
@@ -240,24 +249,16 @@ static __always_inline void handle_irq(struct irq_desc *desc,
__handle_irq(desc, regs);
}
-/*
- * common_interrupt() handles all normal device IRQ's (the special SMP
- * cross-CPU interrupts have their own entry points).
- */
-DEFINE_IDTENTRY_IRQ(common_interrupt)
+static __always_inline int call_irq_handler(int vector, struct pt_regs *regs)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
struct irq_desc *desc;
-
- /* entry code tells RCU that we're not quiescent. Check it. */
- RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
+ int ret = 0;
desc = __this_cpu_read(vector_irq[vector]);
if (likely(!IS_ERR_OR_NULL(desc))) {
handle_irq(desc, regs);
} else {
- apic_eoi();
-
+ ret = -EINVAL;
if (desc == VECTOR_UNUSED) {
pr_emerg_ratelimited("%s: %d.%u No irq handler for vector\n",
__func__, smp_processor_id(),
@@ -267,6 +268,23 @@ DEFINE_IDTENTRY_IRQ(common_interrupt)
}
}
+ return ret;
+}
+
+/*
+ * common_interrupt() handles all normal device IRQ's (the special SMP
+ * cross-CPU interrupts have their own entry points).
+ */
+DEFINE_IDTENTRY_IRQ(common_interrupt)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ /* entry code tells RCU that we're not quiescent. Check it. */
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
+
+ if (unlikely(call_irq_handler(vector, regs)))
+ apic_eoi();
+
set_irq_regs(old_regs);
}
@@ -334,12 +352,139 @@ DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_nested_ipi)
}
#endif
+#ifdef CONFIG_X86_POSTED_MSI
+
+/* Posted Interrupt Descriptors for coalesced MSIs to be posted */
+DEFINE_PER_CPU_ALIGNED(struct pi_desc, posted_msi_pi_desc);
+
+void intel_posted_msi_init(void)
+{
+ u32 destination;
+ u32 apic_id;
+
+ this_cpu_write(posted_msi_pi_desc.nv, POSTED_MSI_NOTIFICATION_VECTOR);
+
+ /*
+ * APIC destination ID is stored in bit 8:15 while in XAPIC mode.
+ * VT-d spec. CH 9.11
+ */
+ apic_id = this_cpu_read(x86_cpu_to_apicid);
+ destination = x2apic_enabled() ? apic_id : apic_id << 8;
+ this_cpu_write(posted_msi_pi_desc.ndst, destination);
+}
+
+/*
+ * De-multiplexing posted interrupts is on the performance path, the code
+ * below is written to optimize the cache performance based on the following
+ * considerations:
+ * 1.Posted interrupt descriptor (PID) fits in a cache line that is frequently
+ * accessed by both CPU and IOMMU.
+ * 2.During posted MSI processing, the CPU needs to do 64-bit read and xchg
+ * for checking and clearing posted interrupt request (PIR), a 256 bit field
+ * within the PID.
+ * 3.On the other side, the IOMMU does atomic swaps of the entire PID cache
+ * line when posting interrupts and setting control bits.
+ * 4.The CPU can access the cache line a magnitude faster than the IOMMU.
+ * 5.Each time the IOMMU does interrupt posting to the PIR will evict the PID
+ * cache line. The cache line states after each operation are as follows:
+ * CPU IOMMU PID Cache line state
+ * ---------------------------------------------------------------
+ *...read64 exclusive
+ *...lock xchg64 modified
+ *... post/atomic swap invalid
+ *...-------------------------------------------------------------
+ *
+ * To reduce L1 data cache miss, it is important to avoid contention with
+ * IOMMU's interrupt posting/atomic swap. Therefore, a copy of PIR is used
+ * to dispatch interrupt handlers.
+ *
+ * In addition, the code is trying to keep the cache line state consistent
+ * as much as possible. e.g. when making a copy and clearing the PIR
+ * (assuming non-zero PIR bits are present in the entire PIR), it does:
+ * read, read, read, read, xchg, xchg, xchg, xchg
+ * instead of:
+ * read, xchg, read, xchg, read, xchg, read, xchg
+ */
+static __always_inline bool handle_pending_pir(u64 *pir, struct pt_regs *regs)
+{
+ int i, vec = FIRST_EXTERNAL_VECTOR;
+ unsigned long pir_copy[4];
+ bool handled = false;
+
+ for (i = 0; i < 4; i++)
+ pir_copy[i] = pir[i];
+
+ for (i = 0; i < 4; i++) {
+ if (!pir_copy[i])
+ continue;
+
+ pir_copy[i] = arch_xchg(&pir[i], 0);
+ handled = true;
+ }
+
+ if (handled) {
+ for_each_set_bit_from(vec, pir_copy, FIRST_SYSTEM_VECTOR)
+ call_irq_handler(vec, regs);
+ }
+
+ return handled;
+}
+
+/*
+ * Performance data shows that 3 is good enough to harvest 90+% of the benefit
+ * on high IRQ rate workload.
+ */
+#define MAX_POSTED_MSI_COALESCING_LOOP 3
+
+/*
+ * For MSIs that are delivered as posted interrupts, the CPU notifications
+ * can be coalesced if the MSIs arrive in high frequency bursts.
+ */
+DEFINE_IDTENTRY_SYSVEC(sysvec_posted_msi_notification)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ struct pi_desc *pid;
+ int i = 0;
+
+ pid = this_cpu_ptr(&posted_msi_pi_desc);
+
+ inc_irq_stat(posted_msi_notification_count);
+ irq_enter();
+
+ /*
+ * Max coalescing count includes the extra round of handle_pending_pir
+ * after clearing the outstanding notification bit. Hence, at most
+ * MAX_POSTED_MSI_COALESCING_LOOP - 1 loops are executed here.
+ */
+ while (++i < MAX_POSTED_MSI_COALESCING_LOOP) {
+ if (!handle_pending_pir(pid->pir64, regs))
+ break;
+ }
+
+ /*
+ * Clear outstanding notification bit to allow new IRQ notifications,
+ * do this last to maximize the window of interrupt coalescing.
+ */
+ pi_clear_on(pid);
+
+ /*
+ * There could be a race of PI notification and the clearing of ON bit,
+ * process PIR bits one last time such that handling the new interrupts
+ * are not delayed until the next IRQ.
+ */
+ handle_pending_pir(pid->pir64, regs);
+
+ apic_eoi();
+ irq_exit();
+ set_irq_regs(old_regs);
+}
+#endif /* X86_POSTED_MSI */
#ifdef CONFIG_HOTPLUG_CPU
/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
void fixup_irqs(void)
{
- unsigned int irr, vector;
+ unsigned int vector;
struct irq_desc *desc;
struct irq_data *data;
struct irq_chip *chip;
@@ -366,8 +511,7 @@ void fixup_irqs(void)
if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector])))
continue;
- irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
- if (irr & (1 << (vector % 32))) {
+ if (is_vector_pending(vector)) {
desc = __this_cpu_read(vector_irq[vector]);
raw_spin_lock(&desc->lock);
diff --git a/arch/x86/kvm/vmx/posted_intr.c b/arch/x86/kvm/vmx/posted_intr.c
index af662312fd07..ec08fa3caf43 100644
--- a/arch/x86/kvm/vmx/posted_intr.c
+++ b/arch/x86/kvm/vmx/posted_intr.c
@@ -107,7 +107,7 @@ void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu)
* handle task migration (@cpu != vcpu->cpu).
*/
new.ndst = dest;
- new.sn = 0;
+ __pi_clear_sn(&new);
/*
* Restore the notification vector; in the blocking case, the
@@ -157,7 +157,7 @@ static void pi_enable_wakeup_handler(struct kvm_vcpu *vcpu)
&per_cpu(wakeup_vcpus_on_cpu, vcpu->cpu));
raw_spin_unlock(&per_cpu(wakeup_vcpus_on_cpu_lock, vcpu->cpu));
- WARN(pi_desc->sn, "PI descriptor SN field set before blocking");
+ WARN(pi_test_sn(pi_desc), "PI descriptor SN field set before blocking");
old.control = READ_ONCE(pi_desc->control);
do {
diff --git a/arch/x86/kvm/vmx/posted_intr.h b/arch/x86/kvm/vmx/posted_intr.h
index 26992076552e..6b2a0226257e 100644
--- a/arch/x86/kvm/vmx/posted_intr.h
+++ b/arch/x86/kvm/vmx/posted_intr.h
@@ -1,98 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __KVM_X86_VMX_POSTED_INTR_H
#define __KVM_X86_VMX_POSTED_INTR_H
-
-#define POSTED_INTR_ON 0
-#define POSTED_INTR_SN 1
-
-#define PID_TABLE_ENTRY_VALID 1
-
-/* Posted-Interrupt Descriptor */
-struct pi_desc {
- u32 pir[8]; /* Posted interrupt requested */
- union {
- struct {
- /* bit 256 - Outstanding Notification */
- u16 on : 1,
- /* bit 257 - Suppress Notification */
- sn : 1,
- /* bit 271:258 - Reserved */
- rsvd_1 : 14;
- /* bit 279:272 - Notification Vector */
- u8 nv;
- /* bit 287:280 - Reserved */
- u8 rsvd_2;
- /* bit 319:288 - Notification Destination */
- u32 ndst;
- };
- u64 control;
- };
- u32 rsvd[6];
-} __aligned(64);
-
-static inline bool pi_test_and_set_on(struct pi_desc *pi_desc)
-{
- return test_and_set_bit(POSTED_INTR_ON,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline bool pi_test_and_clear_on(struct pi_desc *pi_desc)
-{
- return test_and_clear_bit(POSTED_INTR_ON,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline bool pi_test_and_clear_sn(struct pi_desc *pi_desc)
-{
- return test_and_clear_bit(POSTED_INTR_SN,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline bool pi_test_and_set_pir(int vector, struct pi_desc *pi_desc)
-{
- return test_and_set_bit(vector, (unsigned long *)pi_desc->pir);
-}
-
-static inline bool pi_is_pir_empty(struct pi_desc *pi_desc)
-{
- return bitmap_empty((unsigned long *)pi_desc->pir, NR_VECTORS);
-}
-
-static inline void pi_set_sn(struct pi_desc *pi_desc)
-{
- set_bit(POSTED_INTR_SN,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline void pi_set_on(struct pi_desc *pi_desc)
-{
- set_bit(POSTED_INTR_ON,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline void pi_clear_on(struct pi_desc *pi_desc)
-{
- clear_bit(POSTED_INTR_ON,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline void pi_clear_sn(struct pi_desc *pi_desc)
-{
- clear_bit(POSTED_INTR_SN,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline bool pi_test_on(struct pi_desc *pi_desc)
-{
- return test_bit(POSTED_INTR_ON,
- (unsigned long *)&pi_desc->control);
-}
-
-static inline bool pi_test_sn(struct pi_desc *pi_desc)
-{
- return test_bit(POSTED_INTR_SN,
- (unsigned long *)&pi_desc->control);
-}
+#include <asm/posted_intr.h>
void vmx_vcpu_pi_load(struct kvm_vcpu *vcpu, int cpu);
void vmx_vcpu_pi_put(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 22411f4aff53..becefaf95cab 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -70,6 +70,7 @@
#include "x86.h"
#include "smm.h"
#include "vmx_onhyperv.h"
+#include "posted_intr.h"
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
@@ -4844,7 +4845,7 @@ static void __vmx_vcpu_reset(struct kvm_vcpu *vcpu)
* or POSTED_INTR_WAKEUP_VECTOR.
*/
vmx->pi_desc.nv = POSTED_INTR_VECTOR;
- vmx->pi_desc.sn = 1;
+ __pi_set_sn(&vmx->pi_desc);
}
static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 90f9e4434646..7e483366b31e 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -7,10 +7,10 @@
#include <asm/kvm.h>
#include <asm/intel_pt.h>
#include <asm/perf_event.h>
+#include <asm/posted_intr.h>
#include "capabilities.h"
#include "../kvm_cache_regs.h"
-#include "posted_intr.h"
#include "vmcs.h"
#include "vmx_ops.h"
#include "../cpuid.h"