search for: eventfd

...1,9 0t0 1033 /dev/urandom qemu-kvm 13468 qemu 4u a_inode 0,9 0 6936 [signalfd] qemu-kvm 13468 qemu 5u a_inode 0,9 0 6936 [eventpoll] qemu-kvm 13468 qemu 6u a_inode 0,9 0 6936 [eventfd] qemu-kvm 13468 qemu 7u a_inode 0,9 0 6936 [eventpoll] qemu-kvm 13468 qemu 8u a_inode 0,9 0 6936 [eventfd] qemu-kvm 13468 qemu 9u a_inode 0,9 0 6936 [eventfd] qemu-kvm 13468 qemu 10u un...

I ran "ninja check-asan" and no errors. But "ninja check-msan" had 117 errors. I took the first FAILED test, which was for eventfd.cc, and executed the command line creating an eventfd executable in a temporary directory and then executed that file using gdb. Finally, used bt to dump the stack. I've emailed llvm-admin at lists.llvm.org to setup an account since self-registration is disable. After getting an account I'...

...t's more interesting to consider a 'vhost style' driver that > > > can be used with unmodified nvme host OS drivers. > > > > > > Dr. Hannes (CC'ed) had done something like this for megasas a few years > > > back using specialized QEMU emulation + eventfd based LIO fabric driver, > > > and got it working with Linux + MSFT guests. > > > > > > Doing something similar for nvme would (potentially) be on par with > > > current virtio-scsi+vhost-scsi small-block performance for scsi-mq > > > guests, without th...

...t's more interesting to consider a 'vhost style' driver that > > > can be used with unmodified nvme host OS drivers. > > > > > > Dr. Hannes (CC'ed) had done something like this for megasas a few years > > > back using specialized QEMU emulation + eventfd based LIO fabric driver, > > > and got it working with Linux + MSFT guests. > > > > > > Doing something similar for nvme would (potentially) be on par with > > > current virtio-scsi+vhost-scsi small-block performance for scsi-mq > > > guests, without th...

...39;t want to reserve a hardcoded range of memory, I added pci device for this instead. Used together with the kvm unittest patches I posted on kvm mailing list. To use, simply add the device on the pci bus. Example test output: vmcall 1519 .... outl_to_kernel 1745 .... mmio-no-eventfd:pci-mem 9075 mmio-wildcard-eventfd:pci-mem 3529 mmio-datamatch-eventfd:pci-mem 3509 mmio-pv-eventfd:pci-mem 1878 portio-no-eventfd:pci-io 5535 portio-wildcard-eventfd:pci-io 1846 portio-datamatch-eventfd:pci-io 1848 portio-pv-eventfd:pci-io 1842 First interesting concl...

...39;t want to reserve a hardcoded range of memory, I added pci device for this instead. Used together with the kvm unittest patches I posted on kvm mailing list. To use, simply add the device on the pci bus. Example test output: vmcall 1519 .... outl_to_kernel 1745 .... mmio-no-eventfd:pci-mem 9075 mmio-wildcard-eventfd:pci-mem 3529 mmio-datamatch-eventfd:pci-mem 3509 mmio-pv-eventfd:pci-mem 1878 portio-no-eventfd:pci-io 5535 portio-wildcard-eventfd:pci-io 1846 portio-datamatch-eventfd:pci-io 1848 portio-pv-eventfd:pci-io 1842 First interesting concl...

With KVM, MMIO is much slower than PIO, due to the need to do page walk and emulation. But with EPT, it does not have to be: we know the address from the VMCS so if the address is unique, we can look up the eventfd directly, bypassing emulation. Add an interface for userspace to specify this per-address, we can use this e.g. for virtio. The implementation adds a separate bus internally. This serves two purposes: - minimize overhead for old userspace that does not use PV MMIO - minimize disruption in other c...

With KVM, MMIO is much slower than PIO, due to the need to do page walk and emulation. But with EPT, it does not have to be: we know the address from the VMCS so if the address is unique, we can look up the eventfd directly, bypassing emulation. Add an interface for userspace to specify this per-address, we can use this e.g. for virtio. The implementation adds a separate bus internally. This serves two purposes: - minimize overhead for old userspace that does not use PV MMIO - minimize disruption in other c...

...;>>> >>>>>> During the virtio-networking meeting, Michael spots two possible >>>>>> issues: >>>>>> >>>>>> 1) do we need an new uAPI to stop the irq offloading? >>>>>> 2) can interrupt lost during the eventfd ctx? >>>>>> >>>>>> For 1) I think we probably not, we can allocate an independent >>>>>> eventfd which does not map to MSIX. So the consumer can't match >>>>>> the producer and we fallback to eventfd based irq. >>&g...

...;>>> >>>>>> During the virtio-networking meeting, Michael spots two possible >>>>>> issues: >>>>>> >>>>>> 1) do we need an new uAPI to stop the irq offloading? >>>>>> 2) can interrupt lost during the eventfd ctx? >>>>>> >>>>>> For 1) I think we probably not, we can allocate an independent >>>>>> eventfd which does not map to MSIX. So the consumer can't match >>>>>> the producer and we fallback to eventfd based irq. >>&g...

...e-target > > > > I think it's more interesting to consider a 'vhost style' driver that > can be used with unmodified nvme host OS drivers. > > Dr. Hannes (CC'ed) had done something like this for megasas a few years > back using specialized QEMU emulation + eventfd based LIO fabric driver, > and got it working with Linux + MSFT guests. > > Doing something similar for nvme would (potentially) be on par with > current virtio-scsi+vhost-scsi small-block performance for scsi-mq > guests, without the extra burden of a new command set specific virti...

...e-target > > > > I think it's more interesting to consider a 'vhost style' driver that > can be used with unmodified nvme host OS drivers. > > Dr. Hannes (CC'ed) had done something like this for megasas a few years > back using specialized QEMU emulation + eventfd based LIO fabric driver, > and got it working with Linux + MSFT guests. > > Doing something similar for nvme would (potentially) be on par with > current virtio-scsi+vhost-scsi small-block performance for scsi-mq > guests, without the extra burden of a new command set specific virti...

...+++ b/drivers/vhost/Kconfig > @@ -11,19 +11,23 @@ config VHOST_RING > This option is selected by any driver which needs to access > the host side of a virtio ring. > > -menuconfig VHOST > - tristate "Host kernel accelerator for virtio (VHOST)" > - depends on EVENTFD > +config VHOST > + tristate > select VHOST_IOTLB > help > This option is selected by any driver which needs to access > the core of vhost. > > -if VHOST > +menuconfig VHOST_MENU > + bool "VHOST drivers" > + default y > + > +if VHOST_ME...

...+++ b/drivers/vhost/Kconfig > @@ -11,19 +11,23 @@ config VHOST_RING > This option is selected by any driver which needs to access > the host side of a virtio ring. > > -menuconfig VHOST > - tristate "Host kernel accelerator for virtio (VHOST)" > - depends on EVENTFD > +config VHOST > + tristate > select VHOST_IOTLB > help > This option is selected by any driver which needs to access > the core of vhost. > > -if VHOST > +menuconfig VHOST_MENU > + bool "VHOST drivers" > + default y > + > +if VHOST_ME...

...1,23 @@ config VHOST_RING > > > This option is selected by any driver which needs to access > > > the host side of a virtio ring. > > > -menuconfig VHOST > > > - tristate "Host kernel accelerator for virtio (VHOST)" > > > - depends on EVENTFD > > > +config VHOST > > > + tristate > > > select VHOST_IOTLB > > > help > > > This option is selected by any driver which needs to access > > > the core of vhost. > > > -if VHOST > > > +menuconfig VHOST_MENU &g...

...1,23 @@ config VHOST_RING > > > This option is selected by any driver which needs to access > > > the host side of a virtio ring. > > > -menuconfig VHOST > > > - tristate "Host kernel accelerator for virtio (VHOST)" > > > - depends on EVENTFD > > > +config VHOST > > > + tristate > > > select VHOST_IOTLB > > > help > > > This option is selected by any driver which needs to access > > > the core of vhost. > > > -if VHOST > > > +menuconfig VHOST_MENU &g...

? 2023/2/28 17:41, Xie Yongji ??: > Add eventfd for the vdpa callback so that user > can signal it directly instead of running the > callback. It will be used for vhost-vdpa case. > > Signed-off-by: Xie Yongji <xieyongji at bytedance.com> > --- > drivers/vhost/vdpa.c | 2 ++ > drivers/virtio/virtio_vdpa.c |...

...This option is selected by any driver which needs to access > > > > > the host side of a virtio ring. > > > > > -menuconfig VHOST > > > > > - tristate "Host kernel accelerator for virtio (VHOST)" > > > > > - depends on EVENTFD > > > > > +config VHOST > > > > > + tristate > > > > > select VHOST_IOTLB > > > > > help > > > > > This option is selected by any driver which needs to access > > > > > the core of vhost. &...

I've "successfully" built 3.9.0 release but when I run "ninja check-all" I got 208 Unexpected failures: Expected Passes : 33997 Expected Failures : 198 Unsupported Tests : 685 Unexpected Failures: 208 Below is the log I captured running "time ninja check-all | tee ninja-check-all.txt" https://drive.google.com/open?id=0B-KTY7zi7eZHU2hGYTRtd01QZjA

Hi, This is the first attempt to add a new qemu nvme backend using in-kernel nvme target. Most code are ported from qemu-nvme and also borrow code from Hannes Reinecke's rts-megasas. It's similar as vhost-scsi, but doesn't use virtio. The advantage is guest can run unmodified NVMe driver. So guest can be any OS that has a NVMe driver. The goal is to get as good performance as