2015-08-10 13:31:58

by Eric Auger

[permalink] [raw]
Subject: [PATCH v5 0/5] KVM: irqfd consumer based on IRQ bypass manager

This series transforms irqfd into an IRQ bypass consumer and
introduce the infrastructure shared by Intel posted-interrupts
and ARM forwarded IRQ series.

The bypass manager gets compiled for x86 and arm/arm64 when
KVM is used. A new kvm_irqfd.h header is created to externalize
some irqfd declarations going to be used by architecture specific
code. A new CONFIG_HAVE_KVM_IRQ_BYPASS option is introduced
to enable architecture specific IRQ manager hooks.

the series depends on the IRQ bypass manager:
- [PATCH v4] virt: IRQ bypass manager (https://lkml.org/lkml/2015/8/6/526)

can be found at:
https://git.linaro.org/people/eric.auger/linux.git/shortlog/refs/heads/v4.2-rc6-irq-forward-v3

Best Regards

Eric

History:

v4 -> v5:
- remove kvm_arch static inline stubs
- add pr_info on registration failure

v3 -> v4:
- fix compilation for arm/arm64
- rearrange signoffs/history on some patch files

v2 -> v3 (Feng Wu):
- rebase on IRQ bypass manager [PATCH v2] virt: IRQ bypass manager:
https://lkml.org/lkml/2015/7/16/810
- Correct some minor errors and typo
- Add something needed for posted-interrupts

v1 -> v2:
- isolate the bypass manager and irqfd consumer in this series
- take into account Paolo's comments and use container_of strategy and
remove additional fields introduced in v1.
- create kvm_irqfd.h
- add unregistration in irqfd_shutdown

v1: originally part of [RFC 00/17] ARM IRQ forward control based on IRQ
bypass manager (https://lkml.org/lkml/2015/7/2/268)

Eric Auger (4):
KVM: arm/arm64: select IRQ_BYPASS_MANAGER
KVM: create kvm_irqfd.h
KVM: introduce kvm_arch functions for IRQ bypass
KVM: eventfd: add irq bypass consumer management

Feng Wu (1):
KVM: x86: select IRQ_BYPASS_MANAGER

arch/arm/kvm/Kconfig | 2 +
arch/arm/kvm/Makefile | 1 +
arch/arm64/kvm/Kconfig | 2 +
arch/arm64/kvm/Makefile | 1 +
arch/x86/kvm/Kconfig | 2 +
arch/x86/kvm/Makefile | 3 ++
include/linux/kvm_host.h | 10 +++++
include/linux/kvm_irqfd.h | 71 ++++++++++++++++++++++++++++++
virt/kvm/Kconfig | 3 ++
virt/kvm/eventfd.c | 110 ++++++++++++++++------------------------------
10 files changed, 133 insertions(+), 72 deletions(-)
create mode 100644 include/linux/kvm_irqfd.h

--
1.9.1


2015-08-10 13:33:44

by Eric Auger

[permalink] [raw]
Subject: [PATCH v5 1/5] KVM: x86: select IRQ_BYPASS_MANAGER

From: Feng Wu <[email protected]>

Select IRQ_BYPASS_MANAGER for x86 when CONFIG_KVM is set

Signed-off-by: Feng Wu <[email protected]>
---
arch/x86/kvm/Kconfig | 2 ++
arch/x86/kvm/Makefile | 3 +++
2 files changed, 5 insertions(+)

diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index d8a1d56..c951d44 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -3,6 +3,7 @@
#

source "virt/kvm/Kconfig"
+source "virt/lib/Kconfig"

menuconfig VIRTUALIZATION
bool "Virtualization"
@@ -28,6 +29,7 @@ config KVM
select ANON_INODES
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQFD
+ select IRQ_BYPASS_MANAGER
select HAVE_KVM_IRQ_ROUTING
select HAVE_KVM_EVENTFD
select KVM_APIC_ARCHITECTURE
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 67d215c..05cc2d7 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -6,6 +6,9 @@ CFLAGS_svm.o := -I.
CFLAGS_vmx.o := -I.

KVM := ../../../virt/kvm
+LIB := ../../../virt/lib
+
+obj-$(CONFIG_IRQ_BYPASS_MANAGER) += $(LIB)/

kvm-y += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o \
$(KVM)/eventfd.o $(KVM)/irqchip.o $(KVM)/vfio.o
--
1.9.1

2015-08-10 13:32:04

by Eric Auger

[permalink] [raw]
Subject: [PATCH v5 2/5] KVM: arm/arm64: select IRQ_BYPASS_MANAGER

Select IRQ_BYPASS_MANAGER when CONFIG_KVM is set
Also add compilation of virt/lib.

Signed-off-by: Eric Auger <[email protected]>
Signed-off-by: Feng Wu <[email protected]>

---

v3 -> v4:
- add compilation of virt/lib in arm/arm64 KVM

v2 -> v3:
- [Feng Wu] Correct a typo in 'arch/arm64/kvm/Kconfig'

v1 -> v2:
- also set IRQ_BYPASS_MANAGER for arm64
---
arch/arm/kvm/Kconfig | 2 ++
arch/arm/kvm/Makefile | 1 +
arch/arm64/kvm/Kconfig | 2 ++
arch/arm64/kvm/Makefile | 1 +
4 files changed, 6 insertions(+)

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index bfb915d..3c565b9 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -3,6 +3,7 @@
#

source "virt/kvm/Kconfig"
+source "virt/lib/Kconfig"

menuconfig VIRTUALIZATION
bool "Virtualization"
@@ -31,6 +32,7 @@ config KVM
select KVM_VFIO
select HAVE_KVM_EVENTFD
select HAVE_KVM_IRQFD
+ select IRQ_BYPASS_MANAGER
depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER
---help---
Support hosting virtualized guest machines.
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index c5eef02c..a6a41dd 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -24,3 +24,4 @@ obj-y += $(KVM)/arm/vgic.o
obj-y += $(KVM)/arm/vgic-v2.o
obj-y += $(KVM)/arm/vgic-v2-emul.o
obj-y += $(KVM)/arm/arch_timer.o
+obj-y += ../../../virt/lib/
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index bfffe8f..2509539 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -3,6 +3,7 @@
#

source "virt/kvm/Kconfig"
+source "virt/lib/Kconfig"

menuconfig VIRTUALIZATION
bool "Virtualization"
@@ -31,6 +32,7 @@ config KVM
select KVM_VFIO
select HAVE_KVM_EVENTFD
select HAVE_KVM_IRQFD
+ select IRQ_BYPASS_MANAGER
---help---
Support hosting virtualized guest machines.

diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index f90f4aa..55eec69 100644
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -27,3 +27,4 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v3.o
kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic-v3-emul.o
kvm-$(CONFIG_KVM_ARM_HOST) += vgic-v3-switch.o
kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/arch_timer.o
+kvm-$(CONFIG_KVM_ARM_HOST) += ../../../virt/lib/
--
1.9.1

2015-08-10 13:32:13

by Eric Auger

[permalink] [raw]
Subject: [PATCH v5 3/5] KVM: create kvm_irqfd.h

Move _irqfd_resampler and _irqfd struct declarations in a new
public header: kvm_irqfd.h. They are respectively renamed into
kvm_kernel_irqfd_resampler and kvm_kernel_irqfd. Those datatypes
will be used by architecture specific code, in the context of
IRQ bypass manager integration.

Signed-off-by: Eric Auger <[email protected]>
---
include/linux/kvm_irqfd.h | 69 ++++++++++++++++++++++++++++++++++
virt/kvm/eventfd.c | 95 ++++++++++++-----------------------------------
2 files changed, 92 insertions(+), 72 deletions(-)
create mode 100644 include/linux/kvm_irqfd.h

diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h
new file mode 100644
index 0000000..f926b39
--- /dev/null
+++ b/include/linux/kvm_irqfd.h
@@ -0,0 +1,69 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * irqfd: Allows an fd to be used to inject an interrupt to the guest
+ * Credit goes to Avi Kivity for the original idea.
+ */
+
+#ifndef __LINUX_KVM_IRQFD_H
+#define __LINUX_KVM_IRQFD_H
+
+#include <linux/kvm_host.h>
+#include <linux/poll.h>
+
+/*
+ * Resampling irqfds are a special variety of irqfds used to emulate
+ * level triggered interrupts. The interrupt is asserted on eventfd
+ * trigger. On acknowledgment through the irq ack notifier, the
+ * interrupt is de-asserted and userspace is notified through the
+ * resamplefd. All resamplers on the same gsi are de-asserted
+ * together, so we don't need to track the state of each individual
+ * user. We can also therefore share the same irq source ID.
+ */
+struct kvm_kernel_irqfd_resampler {
+ struct kvm *kvm;
+ /*
+ * List of resampling struct _irqfd objects sharing this gsi.
+ * RCU list modified under kvm->irqfds.resampler_lock
+ */
+ struct list_head list;
+ struct kvm_irq_ack_notifier notifier;
+ /*
+ * Entry in list of kvm->irqfd.resampler_list. Use for sharing
+ * resamplers among irqfds on the same gsi.
+ * Accessed and modified under kvm->irqfds.resampler_lock
+ */
+ struct list_head link;
+};
+
+struct kvm_kernel_irqfd {
+ /* Used for MSI fast-path */
+ struct kvm *kvm;
+ wait_queue_t wait;
+ /* Update side is protected by irqfds.lock */
+ struct kvm_kernel_irq_routing_entry irq_entry;
+ seqcount_t irq_entry_sc;
+ /* Used for level IRQ fast-path */
+ int gsi;
+ struct work_struct inject;
+ /* The resampler used by this irqfd (resampler-only) */
+ struct kvm_kernel_irqfd_resampler *resampler;
+ /* Eventfd notified on resample (resampler-only) */
+ struct eventfd_ctx *resamplefd;
+ /* Entry in list of irqfds for a resampler (resampler-only) */
+ struct list_head resampler_link;
+ /* Used for setup/shutdown */
+ struct eventfd_ctx *eventfd;
+ struct list_head list;
+ poll_table pt;
+ struct work_struct shutdown;
+};
+
+#endif /* __LINUX_KVM_IRQFD_H */
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 9ff4193..647ffb8 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -23,6 +23,7 @@

#include <linux/kvm_host.h>
#include <linux/kvm.h>
+#include <linux/kvm_irqfd.h>
#include <linux/workqueue.h>
#include <linux/syscalls.h>
#include <linux/wait.h>
@@ -39,68 +40,14 @@
#include <kvm/iodev.h>

#ifdef CONFIG_HAVE_KVM_IRQFD
-/*
- * --------------------------------------------------------------------
- * irqfd: Allows an fd to be used to inject an interrupt to the guest
- *
- * Credit goes to Avi Kivity for the original idea.
- * --------------------------------------------------------------------
- */
-
-/*
- * Resampling irqfds are a special variety of irqfds used to emulate
- * level triggered interrupts. The interrupt is asserted on eventfd
- * trigger. On acknowledgement through the irq ack notifier, the
- * interrupt is de-asserted and userspace is notified through the
- * resamplefd. All resamplers on the same gsi are de-asserted
- * together, so we don't need to track the state of each individual
- * user. We can also therefore share the same irq source ID.
- */
-struct _irqfd_resampler {
- struct kvm *kvm;
- /*
- * List of resampling struct _irqfd objects sharing this gsi.
- * RCU list modified under kvm->irqfds.resampler_lock
- */
- struct list_head list;
- struct kvm_irq_ack_notifier notifier;
- /*
- * Entry in list of kvm->irqfd.resampler_list. Use for sharing
- * resamplers among irqfds on the same gsi.
- * Accessed and modified under kvm->irqfds.resampler_lock
- */
- struct list_head link;
-};
-
-struct _irqfd {
- /* Used for MSI fast-path */
- struct kvm *kvm;
- wait_queue_t wait;
- /* Update side is protected by irqfds.lock */
- struct kvm_kernel_irq_routing_entry irq_entry;
- seqcount_t irq_entry_sc;
- /* Used for level IRQ fast-path */
- int gsi;
- struct work_struct inject;
- /* The resampler used by this irqfd (resampler-only) */
- struct _irqfd_resampler *resampler;
- /* Eventfd notified on resample (resampler-only) */
- struct eventfd_ctx *resamplefd;
- /* Entry in list of irqfds for a resampler (resampler-only) */
- struct list_head resampler_link;
- /* Used for setup/shutdown */
- struct eventfd_ctx *eventfd;
- struct list_head list;
- poll_table pt;
- struct work_struct shutdown;
-};

static struct workqueue_struct *irqfd_cleanup_wq;

static void
irqfd_inject(struct work_struct *work)
{
- struct _irqfd *irqfd = container_of(work, struct _irqfd, inject);
+ struct kvm_kernel_irqfd *irqfd =
+ container_of(work, struct kvm_kernel_irqfd, inject);
struct kvm *kvm = irqfd->kvm;

if (!irqfd->resampler) {
@@ -121,12 +68,13 @@ irqfd_inject(struct work_struct *work)
static void
irqfd_resampler_ack(struct kvm_irq_ack_notifier *kian)
{
- struct _irqfd_resampler *resampler;
+ struct kvm_kernel_irqfd_resampler *resampler;
struct kvm *kvm;
- struct _irqfd *irqfd;
+ struct kvm_kernel_irqfd *irqfd;
int idx;

- resampler = container_of(kian, struct _irqfd_resampler, notifier);
+ resampler = container_of(kian,
+ struct kvm_kernel_irqfd_resampler, notifier);
kvm = resampler->kvm;

kvm_set_irq(kvm, KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID,
@@ -141,9 +89,9 @@ irqfd_resampler_ack(struct kvm_irq_ack_notifier *kian)
}

static void
-irqfd_resampler_shutdown(struct _irqfd *irqfd)
+irqfd_resampler_shutdown(struct kvm_kernel_irqfd *irqfd)
{
- struct _irqfd_resampler *resampler = irqfd->resampler;
+ struct kvm_kernel_irqfd_resampler *resampler = irqfd->resampler;
struct kvm *kvm = resampler->kvm;

mutex_lock(&kvm->irqfds.resampler_lock);
@@ -168,7 +116,8 @@ irqfd_resampler_shutdown(struct _irqfd *irqfd)
static void
irqfd_shutdown(struct work_struct *work)
{
- struct _irqfd *irqfd = container_of(work, struct _irqfd, shutdown);
+ struct kvm_kernel_irqfd *irqfd =
+ container_of(work, struct kvm_kernel_irqfd, shutdown);
u64 cnt;

/*
@@ -198,7 +147,7 @@ irqfd_shutdown(struct work_struct *work)

/* assumes kvm->irqfds.lock is held */
static bool
-irqfd_is_active(struct _irqfd *irqfd)
+irqfd_is_active(struct kvm_kernel_irqfd *irqfd)
{
return list_empty(&irqfd->list) ? false : true;
}
@@ -209,7 +158,7 @@ irqfd_is_active(struct _irqfd *irqfd)
* assumes kvm->irqfds.lock is held
*/
static void
-irqfd_deactivate(struct _irqfd *irqfd)
+irqfd_deactivate(struct kvm_kernel_irqfd *irqfd)
{
BUG_ON(!irqfd_is_active(irqfd));

@@ -224,7 +173,8 @@ irqfd_deactivate(struct _irqfd *irqfd)
static int
irqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
{
- struct _irqfd *irqfd = container_of(wait, struct _irqfd, wait);
+ struct kvm_kernel_irqfd *irqfd =
+ container_of(wait, struct kvm_kernel_irqfd, wait);
unsigned long flags = (unsigned long)key;
struct kvm_kernel_irq_routing_entry irq;
struct kvm *kvm = irqfd->kvm;
@@ -274,12 +224,13 @@ static void
irqfd_ptable_queue_proc(struct file *file, wait_queue_head_t *wqh,
poll_table *pt)
{
- struct _irqfd *irqfd = container_of(pt, struct _irqfd, pt);
+ struct kvm_kernel_irqfd *irqfd =
+ container_of(pt, struct kvm_kernel_irqfd, pt);
add_wait_queue(wqh, &irqfd->wait);
}

/* Must be called under irqfds.lock */
-static void irqfd_update(struct kvm *kvm, struct _irqfd *irqfd)
+static void irqfd_update(struct kvm *kvm, struct kvm_kernel_irqfd *irqfd)
{
struct kvm_kernel_irq_routing_entry *e;
struct kvm_kernel_irq_routing_entry entries[KVM_NR_IRQCHIPS];
@@ -304,7 +255,7 @@ static void irqfd_update(struct kvm *kvm, struct _irqfd *irqfd)
static int
kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
{
- struct _irqfd *irqfd, *tmp;
+ struct kvm_kernel_irqfd *irqfd, *tmp;
struct fd f;
struct eventfd_ctx *eventfd = NULL, *resamplefd = NULL;
int ret;
@@ -340,7 +291,7 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
irqfd->eventfd = eventfd;

if (args->flags & KVM_IRQFD_FLAG_RESAMPLE) {
- struct _irqfd_resampler *resampler;
+ struct kvm_kernel_irqfd_resampler *resampler;

resamplefd = eventfd_ctx_fdget(args->resamplefd);
if (IS_ERR(resamplefd)) {
@@ -525,7 +476,7 @@ kvm_eventfd_init(struct kvm *kvm)
static int
kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd *args)
{
- struct _irqfd *irqfd, *tmp;
+ struct kvm_kernel_irqfd *irqfd, *tmp;
struct eventfd_ctx *eventfd;

eventfd = eventfd_ctx_fdget(args->fd);
@@ -581,7 +532,7 @@ kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args)
void
kvm_irqfd_release(struct kvm *kvm)
{
- struct _irqfd *irqfd, *tmp;
+ struct kvm_kernel_irqfd *irqfd, *tmp;

spin_lock_irq(&kvm->irqfds.lock);

@@ -604,7 +555,7 @@ kvm_irqfd_release(struct kvm *kvm)
*/
void kvm_irq_routing_update(struct kvm *kvm)
{
- struct _irqfd *irqfd;
+ struct kvm_kernel_irqfd *irqfd;

spin_lock_irq(&kvm->irqfds.lock);

--
1.9.1

2015-08-10 13:32:09

by Eric Auger

[permalink] [raw]
Subject: [PATCH v5 4/5] KVM: introduce kvm_arch functions for IRQ bypass

This patch introduces
- kvm_arch_irq_bypass_add_producer
- kvm_arch_irq_bypass_del_producer
- kvm_arch_irq_bypass_stop
- kvm_arch_irq_bypass_start

They make possible to specialize the KVM IRQ bypass consumer in
case CONFIG_KVM_HAVE_IRQ_BYPASS is set.

Signed-off-by: Eric Auger <[email protected]>
Signed-off-by: Feng Wu <[email protected]>

---
v4 -> v5:
- remove static inline stub functions

v2 -> v3 (Feng Wu):
- use 'kvm_arch_irq_bypass_start' instead of 'kvm_arch_irq_bypass_resume'
- Remove 'kvm_arch_irq_bypass_update', which is not needed to be
a irqbypass callback per Alex's comments.
- Make kvm_arch_irq_bypass_add_producer return 'int'

v1 -> v2:
- use CONFIG_KVM_HAVE_IRQ_BYPASS instead CONFIG_IRQ_BYPASS_MANAGER
- rename all functions according to Paolo's proposal
- add kvm_arch_irq_bypass_update according to Feng's need
---
include/linux/kvm_host.h | 10 ++++++++++
virt/kvm/Kconfig | 3 +++
2 files changed, 13 insertions(+)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 05e99b8..5ac8d21 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -24,6 +24,7 @@
#include <linux/err.h>
#include <linux/irqflags.h>
#include <linux/context_tracking.h>
+#include <linux/irqbypass.h>
#include <asm/signal.h>

#include <linux/kvm.h>
@@ -1151,5 +1152,14 @@ static inline void kvm_vcpu_set_dy_eligible(struct kvm_vcpu *vcpu, bool val)
{
}
#endif /* CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT */
+
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *,
+ struct irq_bypass_producer *);
+void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *,
+ struct irq_bypass_producer *);
+void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *);
+void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *);
+#endif /* CONFIG_HAVE_KVM_IRQ_BYPASS */
#endif

diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index e2c876d..9f8014d 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -47,3 +47,6 @@ config KVM_GENERIC_DIRTYLOG_READ_PROTECT
config KVM_COMPAT
def_bool y
depends on COMPAT && !S390
+
+config HAVE_KVM_IRQ_BYPASS
+ bool
--
1.9.1

2015-08-10 13:33:19

by Eric Auger

[permalink] [raw]
Subject: [PATCH v5 5/5] KVM: eventfd: add irq bypass consumer management

This patch adds the registration/unregistration of an
irq_bypass_consumer on irqfd assignment/deassignment.

Signed-off-by: Eric Auger <[email protected]>
Signed-off-by: Feng Wu <[email protected]>

---

v4 -> v5:
- due to removal of static inline stubs, add
#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
around consumer registration/unregistration
- add pr_info when registration fails

v2 -> v3 (Feng Wu):
- Use kvm_arch_irq_bypass_start
- Remove kvm_arch_irq_bypass_update
- Add member 'struct irq_bypass_producer *producer' in
'struct kvm_kernel_irqfd', it is needed by posted interrupt.
- Remove 'irq_bypass_unregister_consumer' in kvm_irqfd_deassign()

v1 -> v2:
- populate of kvm and gsi removed
- unregister the consumer on irqfd_shutdown
---
include/linux/kvm_irqfd.h | 2 ++
virt/kvm/eventfd.c | 15 +++++++++++++++
2 files changed, 17 insertions(+)

diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h
index f926b39..0c1de05 100644
--- a/include/linux/kvm_irqfd.h
+++ b/include/linux/kvm_irqfd.h
@@ -64,6 +64,8 @@ struct kvm_kernel_irqfd {
struct list_head list;
poll_table pt;
struct work_struct shutdown;
+ struct irq_bypass_consumer consumer;
+ struct irq_bypass_producer *producer;
};

#endif /* __LINUX_KVM_IRQFD_H */
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index 647ffb8..d7a230f 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -35,6 +35,7 @@
#include <linux/srcu.h>
#include <linux/slab.h>
#include <linux/seqlock.h>
+#include <linux/irqbypass.h>
#include <trace/events/kvm.h>

#include <kvm/iodev.h>
@@ -140,6 +141,9 @@ irqfd_shutdown(struct work_struct *work)
/*
* It is now safe to release the object's resources
*/
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+ irq_bypass_unregister_consumer(&irqfd->consumer);
+#endif
eventfd_ctx_put(irqfd->eventfd);
kfree(irqfd);
}
@@ -379,6 +383,17 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
* we might race against the POLLHUP
*/
fdput(f);
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+ irqfd->consumer.token = (void *)irqfd->eventfd;
+ irqfd->consumer.add_producer = kvm_arch_irq_bypass_add_producer;
+ irqfd->consumer.del_producer = kvm_arch_irq_bypass_del_producer;
+ irqfd->consumer.stop = kvm_arch_irq_bypass_stop;
+ irqfd->consumer.start = kvm_arch_irq_bypass_start;
+ ret = irq_bypass_register_consumer(&irqfd->consumer);
+ if (ret)
+ pr_info("irq bypass consumer (token %p) registration fails: %d\n",
+ irqfd->consumer.token, ret);
+#endif

return 0;

--
1.9.1

2015-08-12 19:05:12

by Alex Williamson

[permalink] [raw]
Subject: Re: [PATCH v5 5/5] KVM: eventfd: add irq bypass consumer management

On Mon, 2015-08-10 at 15:31 +0200, Eric Auger wrote:
> This patch adds the registration/unregistration of an
> irq_bypass_consumer on irqfd assignment/deassignment.
>
> Signed-off-by: Eric Auger <[email protected]>
> Signed-off-by: Feng Wu <[email protected]>
>
> ---
>
> v4 -> v5:
> - due to removal of static inline stubs, add
> #ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
> around consumer registration/unregistration
> - add pr_info when registration fails
>
> v2 -> v3 (Feng Wu):
> - Use kvm_arch_irq_bypass_start
> - Remove kvm_arch_irq_bypass_update
> - Add member 'struct irq_bypass_producer *producer' in
> 'struct kvm_kernel_irqfd', it is needed by posted interrupt.
> - Remove 'irq_bypass_unregister_consumer' in kvm_irqfd_deassign()
>
> v1 -> v2:
> - populate of kvm and gsi removed
> - unregister the consumer on irqfd_shutdown
> ---
> include/linux/kvm_irqfd.h | 2 ++
> virt/kvm/eventfd.c | 15 +++++++++++++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h
> index f926b39..0c1de05 100644
> --- a/include/linux/kvm_irqfd.h
> +++ b/include/linux/kvm_irqfd.h
> @@ -64,6 +64,8 @@ struct kvm_kernel_irqfd {
> struct list_head list;
> poll_table pt;
> struct work_struct shutdown;
> + struct irq_bypass_consumer consumer;
> + struct irq_bypass_producer *producer;
> };
>
> #endif /* __LINUX_KVM_IRQFD_H */
> diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
> index 647ffb8..d7a230f 100644
> --- a/virt/kvm/eventfd.c
> +++ b/virt/kvm/eventfd.c
> @@ -35,6 +35,7 @@
> #include <linux/srcu.h>
> #include <linux/slab.h>
> #include <linux/seqlock.h>
> +#include <linux/irqbypass.h>
> #include <trace/events/kvm.h>
>
> #include <kvm/iodev.h>
> @@ -140,6 +141,9 @@ irqfd_shutdown(struct work_struct *work)
> /*
> * It is now safe to release the object's resources
> */
> +#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
> + irq_bypass_unregister_consumer(&irqfd->consumer);
> +#endif
> eventfd_ctx_put(irqfd->eventfd);
> kfree(irqfd);
> }
> @@ -379,6 +383,17 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
> * we might race against the POLLHUP
> */
> fdput(f);
> +#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
> + irqfd->consumer.token = (void *)irqfd->eventfd;
> + irqfd->consumer.add_producer = kvm_arch_irq_bypass_add_producer;
> + irqfd->consumer.del_producer = kvm_arch_irq_bypass_del_producer;
> + irqfd->consumer.stop = kvm_arch_irq_bypass_stop;
> + irqfd->consumer.start = kvm_arch_irq_bypass_start;
> + ret = irq_bypass_register_consumer(&irqfd->consumer);
> + if (ret)
> + pr_info("irq bypass consumer (token %p) registration fails: %d\n",
> + irqfd->consumer.token, ret);
> +#endif

Does this series compile on its own? Aren't all these arch function
unresolved?

>
> return 0;
>


2015-08-13 09:20:09

by Eric Auger

[permalink] [raw]
Subject: Re: [PATCH v5 5/5] KVM: eventfd: add irq bypass consumer management

Hi Alex,
On 08/12/2015 09:05 PM, Alex Williamson wrote:
> On Mon, 2015-08-10 at 15:31 +0200, Eric Auger wrote:
>> This patch adds the registration/unregistration of an
>> irq_bypass_consumer on irqfd assignment/deassignment.
>>
>> Signed-off-by: Eric Auger <[email protected]>
>> Signed-off-by: Feng Wu <[email protected]>
>>
>> ---
>>
>> v4 -> v5:
>> - due to removal of static inline stubs, add
>> #ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
>> around consumer registration/unregistration
>> - add pr_info when registration fails
>>
>> v2 -> v3 (Feng Wu):
>> - Use kvm_arch_irq_bypass_start
>> - Remove kvm_arch_irq_bypass_update
>> - Add member 'struct irq_bypass_producer *producer' in
>> 'struct kvm_kernel_irqfd', it is needed by posted interrupt.
>> - Remove 'irq_bypass_unregister_consumer' in kvm_irqfd_deassign()
>>
>> v1 -> v2:
>> - populate of kvm and gsi removed
>> - unregister the consumer on irqfd_shutdown
>> ---
>> include/linux/kvm_irqfd.h | 2 ++
>> virt/kvm/eventfd.c | 15 +++++++++++++++
>> 2 files changed, 17 insertions(+)
>>
>> diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h
>> index f926b39..0c1de05 100644
>> --- a/include/linux/kvm_irqfd.h
>> +++ b/include/linux/kvm_irqfd.h
>> @@ -64,6 +64,8 @@ struct kvm_kernel_irqfd {
>> struct list_head list;
>> poll_table pt;
>> struct work_struct shutdown;
>> + struct irq_bypass_consumer consumer;
>> + struct irq_bypass_producer *producer;
>> };
>>
>> #endif /* __LINUX_KVM_IRQFD_H */
>> diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
>> index 647ffb8..d7a230f 100644
>> --- a/virt/kvm/eventfd.c
>> +++ b/virt/kvm/eventfd.c
>> @@ -35,6 +35,7 @@
>> #include <linux/srcu.h>
>> #include <linux/slab.h>
>> #include <linux/seqlock.h>
>> +#include <linux/irqbypass.h>
>> #include <trace/events/kvm.h>
>>
>> #include <kvm/iodev.h>
>> @@ -140,6 +141,9 @@ irqfd_shutdown(struct work_struct *work)
>> /*
>> * It is now safe to release the object's resources
>> */
>> +#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
>> + irq_bypass_unregister_consumer(&irqfd->consumer);
>> +#endif
>> eventfd_ctx_put(irqfd->eventfd);
>> kfree(irqfd);
>> }
>> @@ -379,6 +383,17 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
>> * we might race against the POLLHUP
>> */
>> fdput(f);
>> +#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
>> + irqfd->consumer.token = (void *)irqfd->eventfd;
>> + irqfd->consumer.add_producer = kvm_arch_irq_bypass_add_producer;
>> + irqfd->consumer.del_producer = kvm_arch_irq_bypass_del_producer;
>> + irqfd->consumer.stop = kvm_arch_irq_bypass_stop;
>> + irqfd->consumer.start = kvm_arch_irq_bypass_start;
>> + ret = irq_bypass_register_consumer(&irqfd->consumer);
>> + if (ret)
>> + pr_info("irq bypass consumer (token %p) registration fails: %d\n",
>> + irqfd->consumer.token, ret);
>> +#endif
>
> Does this series compile on its own? Aren't all these arch function
> unresolved?
yes it does since by default CONFIG_HAVE_KVM_IRQ_BYPASS is not defined

Best Regards

Eric
>
>>
>> return 0;
>>
>
>
>