Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
Hi Jan and Cam,
It has been tested with uio driver. And other opinion for the code?
Regards,
Pingfan
On Thu, Dec 6, 2012 at 2:37 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
Signed-off-by: Cam Macdonell c...@cs.ualberta.ca
---
hw/ivshmem.c | 54 +-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..b394b07 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque, int
version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq) =
0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msix_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On 2012-12-05 06:34, Cam Macdonell wrote:
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
Problem 1) in my tests is_enabled is always 0, so I don't think the
irqfds are getting setup
You likely want to call msix_enabled here.
Jan
--
Siemens AG, Corporate Technology, CT RTC ITP SDP-DE
Corporate Competence Center Embedded Linux
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
- Original Message -
On Tue, Dec 4, 2012 at 4:10 AM, Andrew Jones drjo...@redhat.com
wrote:
- Original Message -
On Thu, Nov 29, 2012 at 1:34 AM, liu ping fan qemul...@gmail.com
wrote:
On Thu, Nov 29, 2012 at 12:42 PM, Cam Macdonell
c...@cs.ualberta.ca wrote:
On Tue, Nov 27, 2012 at 7:53 PM, liu ping fan
qemul...@gmail.com
wrote:
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell
c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan
qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user
when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small
delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from
git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and
vm-id
bits
position (the codes conflict with ivshmem spec), it works (I
have
tested for V1).
Hello,
Which device driver are you using?
guest-code/kernel_module/standard/kvm_ivshmem.c
The uio driver is the recommended one, however if you want to use
the
kvm_ivshmem one and have it working, then feel free to continue.
If the uio driver is the recommended one, then can you please post
it
to lkml? It should be integrated into drivers/virt with an
appropriate
Kconfig update.
Sure. Should it go under drivers/virt or drivers/uio? It seems the
uio drivers all get grouped together.
Good point. That is the current practice. As there's still only a
handful of uio drivers, then I guess it doesn't make sense to try and
change that at this point. It seems that it would make more sense to
use drivers/uio just for generic uio drivers though, and then the other
uio drivers would go under drivers/type/uio, e.g. drivers/virt/uio
Drew
Thanks,
Cam
Thanks,
Drew
I had deleted it form the repo, but some users had based solutions
off
it, so I added it back.
btw, my hardware issue has been resolved, so I'll get to testing
your
patch soon.
Sincerely,
Cam
Cam
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54
+-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f,
void
*opaque, int version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned
vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n =
s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0
kvm_irqchip_add_irqfd_notifier(kvm_state,
n, virq) = 0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL,
NULL, NULL, NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup
irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned
vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n =
s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n,
virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev,
uint32_t
address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev,
ivshmem_vector_use,
+ivshmem_vector_release);
+} else if
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Wed, Dec 5, 2012 at 1:50 AM, Jan Kiszka jan.kis...@siemens.com wrote:
On 2012-12-05 06:34, Cam Macdonell wrote:
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
Problem 1) in my tests is_enabled is always 0, so I don't think the
irqfds are getting setup
You likely want to call msix_enabled here.
Yup, that gets it working.
Liu Ping, can you update the patch to use msix_enabled()?
Also, it seems that with irqfd enabled the user-level handlers are not
triggered, but it may still be a better idea to not add the user-level
handlers to the char devices at all if irqfd is enabled.
Cam
Jan
--
Siemens AG, Corporate Technology, CT RTC ITP SDP-DE
Corporate Competence Center Embedded Linux
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Thu, Dec 6, 2012 at 1:10 PM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Wed, Dec 5, 2012 at 1:50 AM, Jan Kiszka jan.kis...@siemens.com wrote:
On 2012-12-05 06:34, Cam Macdonell wrote:
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
Problem 1) in my tests is_enabled is always 0, so I don't think the
irqfds are getting setup
You likely want to call msix_enabled here.
Yup, that gets it working.
Liu Ping, can you update the patch to use msix_enabled()?
:-) , I just finish my test on uio before reading this
Also, it seems that with irqfd enabled the user-level handlers are not
triggered, but it may still be a better idea to not add the user-level
handlers to the char devices at all if irqfd is enabled.
Here, in ivshmem_vector_use(),
qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL, NULL)
serves this purpose. When irqfd enabled, the fake_irqfd will be
removed from eventfd's listeners.
I will fix the msix_enabled, and send out next version.
Regards,
Pingfan
Cam
Jan
--
Siemens AG, Corporate Technology, CT RTC ITP SDP-DE
Corporate Competence Center Embedded Linux
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
- Original Message -
On Thu, Nov 29, 2012 at 1:34 AM, liu ping fan qemul...@gmail.com
wrote:
On Thu, Nov 29, 2012 at 12:42 PM, Cam Macdonell
c...@cs.ualberta.ca wrote:
On Tue, Nov 27, 2012 at 7:53 PM, liu ping fan qemul...@gmail.com
wrote:
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell
c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan
qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user
when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small
delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from
git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and vm-id
bits
position (the codes conflict with ivshmem spec), it works (I have
tested for V1).
Hello,
Which device driver are you using?
guest-code/kernel_module/standard/kvm_ivshmem.c
The uio driver is the recommended one, however if you want to use the
kvm_ivshmem one and have it working, then feel free to continue.
If the uio driver is the recommended one, then can you please post it
to lkml? It should be integrated into drivers/virt with an appropriate
Kconfig update.
Thanks,
Drew
I had deleted it form the repo, but some users had based solutions
off
it, so I added it back.
btw, my hardware issue has been resolved, so I'll get to testing your
patch soon.
Sincerely,
Cam
Cam
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54
+-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void
*opaque, int version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state,
n, virq) = 0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL,
NULL, NULL, NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup
irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned
vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t
address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice
*dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice
*dev)
migrate_del_blocker(s-migration_blocker);
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Tue, Dec 4, 2012 at 4:10 AM, Andrew Jones drjo...@redhat.com wrote:
- Original Message -
On Thu, Nov 29, 2012 at 1:34 AM, liu ping fan qemul...@gmail.com
wrote:
On Thu, Nov 29, 2012 at 12:42 PM, Cam Macdonell
c...@cs.ualberta.ca wrote:
On Tue, Nov 27, 2012 at 7:53 PM, liu ping fan qemul...@gmail.com
wrote:
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell
c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan
qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user
when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small
delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from
git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and vm-id
bits
position (the codes conflict with ivshmem spec), it works (I have
tested for V1).
Hello,
Which device driver are you using?
guest-code/kernel_module/standard/kvm_ivshmem.c
The uio driver is the recommended one, however if you want to use the
kvm_ivshmem one and have it working, then feel free to continue.
If the uio driver is the recommended one, then can you please post it
to lkml? It should be integrated into drivers/virt with an appropriate
Kconfig update.
Sure. Should it go under drivers/virt or drivers/uio? It seems the
uio drivers all get grouped together.
Thanks,
Cam
Thanks,
Drew
I had deleted it form the repo, but some users had based solutions
off
it, so I added it back.
btw, my hardware issue has been resolved, so I'll get to testing your
patch soon.
Sincerely,
Cam
Cam
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54
+-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void
*opaque, int version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state,
n, virq) = 0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL,
NULL, NULL, NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup
irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned
vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t
address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice
*dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] =
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Hi Liu Ping,
With this patch applied I was still seeing transitions to user-level
on the receipt of an msi interrupt.
uncomment DEBUG_IVSHMEM in hw/ivshmem.c (and fix one compile error in
the debug statement :) )
IVSHMEM: msix initialized (1 vectors)
...
IVSHMEM: interrupt on vector 0x7f2971b1d8d0 0
IVSHMEM: interrupt on vector 0x7f2971b1d8d0 0
if we're using irqfd, this should be avoided. Here's my command-line:
-device ivshmem,chardev=nahanni,msi=on,ioeventfd=on,size=2048,use64=1,role=peer
There are two issues as I see it:
1) irqfd is not being enabled in my tests
2) the defaults handlers are still being added
One difference is that I'm using the UIO driver, which enables PCI
using pci_enable_msix as follows
pci_enable_msix(ivs_info-dev, ivs_info-msix_entries,
ivs_info-nvectors);
and succeeds
[2.651253] uio_ivshmem :00:04.0: irq 43 for MSI/MSI-X
[2.651326] MSI-X enabled
(continued below)
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54 +-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque, int
version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq) =
0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
Problem 1) in my tests is_enabled is always 0, so I don't think the
irqfds are getting setup
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
Problem 2)
We'll also have to not add the handlers as below if irqfd is present
otherwise we'll get double interrupts, so we'll have to add a check
here too.
/* if MSI is supported we need multiple interrupts */
if (!ivshmem_has_feature(s, IVSHMEM_MSI)) {
s-eventfd_table[vector].pdev = s-dev;
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Thu, Nov 29, 2012 at 12:42 PM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Tue, Nov 27, 2012 at 7:53 PM, liu ping fan qemul...@gmail.com wrote:
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and vm-id bits
position (the codes conflict with ivshmem spec), it works (I have
tested for V1).
Hello,
Which device driver are you using?
guest-code/kernel_module/standard/kvm_ivshmem.c
Cam
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54 +-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque,
int version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq)
= 0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Thu, Nov 29, 2012 at 1:34 AM, liu ping fan qemul...@gmail.com wrote:
On Thu, Nov 29, 2012 at 12:42 PM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Tue, Nov 27, 2012 at 7:53 PM, liu ping fan qemul...@gmail.com wrote:
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and vm-id bits
position (the codes conflict with ivshmem spec), it works (I have
tested for V1).
Hello,
Which device driver are you using?
guest-code/kernel_module/standard/kvm_ivshmem.c
The uio driver is the recommended one, however if you want to use the
kvm_ivshmem one and have it working, then feel free to continue.
I had deleted it form the repo, but some users had based solutions off
it, so I added it back.
btw, my hardware issue has been resolved, so I'll get to testing your
patch soon.
Sincerely,
Cam
Cam
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54
+-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque,
int version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq)
= 0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Tue, Nov 27, 2012 at 7:53 PM, liu ping fan qemul...@gmail.com wrote:
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and vm-id bits
position (the codes conflict with ivshmem spec), it works (I have
tested for V1).
Hello,
Which device driver are you using?
Cam
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54 +-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque,
int version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq) =
0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small delay in
me being able to test this. I'll follow up as soon as I can.
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54 +-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque, int
version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq) =
0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
Re: [Qemu-devel] [PATCH v2 2/2] ivshmem: use irqfd to interrupt among VMs
On Wed, Nov 28, 2012 at 5:48 AM, Cam Macdonell c...@cs.ualberta.ca wrote:
On Sat, Nov 24, 2012 at 8:51 PM, Liu Ping Fan qemul...@gmail.com wrote:
From: Liu Ping Fan pingf...@linux.vnet.ibm.com
Using irqfd, so we can avoid switch between kernel and user when
VMs interrupts each other.
Nice work. Due to a hardware failure, there will be a small delay in
me being able to test this. I'll follow up as soon as I can.
BTW where can I find the latest guest code for test?
I got the guest code from git://gitorious.org/nahanni/guest-code.git.
But it seems outdated, after fixing the unlocked_ioctl, and vm-id bits
position (the codes conflict with ivshmem spec), it works (I have
tested for V1).
Regards,
Pingfan
Signed-off-by: Liu Ping Fan pingf...@linux.vnet.ibm.com
---
hw/ivshmem.c | 54 +-
1 files changed, 53 insertions(+), 1 deletions(-)
diff --git a/hw/ivshmem.c b/hw/ivshmem.c
index 7c8630c..5709e89 100644
--- a/hw/ivshmem.c
+++ b/hw/ivshmem.c
@@ -19,6 +19,7 @@
#include hw.h
#include pc.h
#include pci.h
+#include msi.h
#include msix.h
#include kvm.h
#include migration.h
@@ -83,6 +84,7 @@ typedef struct IVShmemState {
uint32_t vectors;
uint32_t features;
EventfdEntry *eventfd_table;
+int *vector_virqs;
Error *migration_blocker;
@@ -625,16 +627,62 @@ static int ivshmem_load(QEMUFile* f, void *opaque, int
version_id)
return 0;
}
+static int ivshmem_vector_use(PCIDevice *dev, unsigned vector,
+ MSIMessage msg)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+int virq;
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+
+virq = kvm_irqchip_add_msi_route(kvm_state, msg);
+if (virq = 0 kvm_irqchip_add_irqfd_notifier(kvm_state, n, virq) =
0) {
+s-vector_virqs[vector] = virq;
+qemu_chr_add_handlers(s-eventfd_chr[vector], NULL, NULL, NULL,
NULL);
+} else if (virq = 0) {
+kvm_irqchip_release_virq(kvm_state, virq);
+error_report(ivshmem, can not setup irqfd\n);
+return -1;
+} else {
+error_report(ivshmem, no enough msi route to setup irqfd\n);
+return -1;
+}
+
+return 0;
+}
+
+static void ivshmem_vector_release(PCIDevice *dev, unsigned vector)
+{
+IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
+EventNotifier *n = s-peers[s-vm_id].eventfds[vector];
+int virq = s-vector_virqs[vector];
+
+if (s-vector_virqs[vector] = 0) {
+kvm_irqchip_remove_irqfd_notifier(kvm_state, n, virq);
+kvm_irqchip_release_virq(kvm_state, virq);
+s-vector_virqs[vector] = -1;
+}
+}
+
static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
+bool is_enabled, was_enabled = msi_enabled(pci_dev);
+
pci_default_write_config(pci_dev, address, val, len);
+is_enabled = msi_enabled(pci_dev);
+if (!was_enabled is_enabled) {
+msix_set_vector_notifiers(pci_dev, ivshmem_vector_use,
+ivshmem_vector_release);
+} else if (was_enabled !is_enabled) {
+msix_unset_vector_notifiers(pci_dev);
+}
}
static int pci_ivshmem_init(PCIDevice *dev)
{
IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
uint8_t *pci_conf;
+int i;
if (s-sizearg == NULL)
s-ivshmem_size = 4 20; /* 4 MB default */
@@ -758,7 +806,10 @@ static int pci_ivshmem_init(PCIDevice *dev)
}
s-dev.config_write = ivshmem_write_config;
-
+s-vector_virqs = g_new0(int, s-vectors);
+for (i = 0; i s-vectors; i++) {
+s-vector_virqs[i] = -1;
+}
return 0;
}
@@ -770,6 +821,7 @@ static void pci_ivshmem_uninit(PCIDevice *dev)
migrate_del_blocker(s-migration_blocker);
error_free(s-migration_blocker);
}
+g_free(s-vector_virqs);
memory_region_destroy(s-ivshmem_mmio);
memory_region_del_subregion(s-bar, s-ivshmem);
--
1.7.4.4
