Commit Graph

9 Commits

Author SHA1 Message Date
Eric Auger
f41389ae3c KVM_CAP_IRQFD and KVM_CAP_IRQFD_RESAMPLE checks
Compute kvm_irqfds_allowed by checking the KVM_CAP_IRQFD extension.
Remove direct settings in architecture specific files.

Add a new kvm_resamplefds_allowed variable, initialized by
checking the KVM_CAP_IRQFD_RESAMPLE extension. Add a corresponding
kvm_resamplefds_enabled() function.

A special notice for s390 where KVM_CAP_IRQFD was not immediatly
advirtised when irqfd capability was introduced in the kernel.
KVM_CAP_IRQ_ROUTING was advertised instead.

This was fixed in "KVM: s390: announce irqfd capability",
ebc3226202d5956a5963185222982d435378b899 whereas irqfd support
was brought in 84223598778ba08041f4297fda485df83414d57e,
"KVM: s390: irq routing for adapter interrupts".  Both commits
first appear in 3.15 so there should not be any kernel
version impacted by this QEMU modification.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:01 +01:00
Alexey Kardashevskiy
a7e519a8cf xics: Disable flags reset on xics reset
Since islsi[] array has been merged into the ICSState struct,
we must not reset flags as they tell if the interrupt is in use.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-27 13:48:26 +02:00
Alexey Kardashevskiy
4af88944d0 xics: Add flags for interrupts
The existing interrupt allocation scheme in SPAPR assumes that
interrupts are allocated at the start time, continously and the config
will not change. However, there are cases when this is not going to work
such as:

1. migration - we will have to have an ability to choose interrupt
numbers for devices in the command line and this will create gaps in
interrupt space.

2. PCI hotplug - interrupts from unplugged device need to be returned
back to interrupt pool, otherwise we will quickly run out of interrupts.

This replaces a separate lslsi[] array with a byte in the ICSIRQState
struct and defines "LSI" and "MSI" flags. Neither of these flags set
signals that the descriptor is not allocated and not in use.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-27 13:48:26 +02:00
Alexey Kardashevskiy
3a3b8502e6 spapr: Fix RTAS token numbers
At the moment spapr_rtas_register() allocates a new token number for every
new RTAS callback so numbers are not fixed and depend on the number of
supported RTAS handlers and the exact order of spapr_rtas_register() calls.
These tokens are copied into the device tree and remain the same during
the guest lifetime.

When we start another guest to receive a migration, it calls
spapr_rtas_register() as well. If the number of RTAS handlers or their
order is different in QEMU on source and destination sides, the "/rtas"
node in the device tree will differ. Since migration overwrites the device
tree (as it overwrites the entire RAM), the actual RTAS config on
the destination side gets broken.

This defines global contant values for every RTAS token which QEMU
is using today.

This changes spapr_rtas_register() to accept a token number instead of
allocating one. This changes all users of spapr_rtas_register().

This changes XICS-KVM not to cache tokens registered with KVM as they
constant now.

This makes TOKEN_BASE global as RTAS_XXX use TOKEN_BASE as
a base. TOKEN_MAX is moved and renamed too and its value is changed
to the last token + 1. Boundary checks for token values are adjusted.

This reserves token numbers for "os-term" handlers and PCI hotplug
which we are working on.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-27 13:48:22 +02:00
Cornelia Huck
48add816cf ppc: use kvm_vcpu_enable_cap()
Convert existing users of KVM_ENABLE_CAP to new helper.

Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2014-04-30 14:39:58 +02:00
Alexey Kardashevskiy
fb0e843a11 xics-kvm: Fix reset function
Currently interrupt priorities are set to 0 (highest) at the very
beginning of the guest execution which is not correct and makes the guest
produce random interrupt error messages such as:
"Interrupt 0x1001 (real) is invalid, disabling it".
This also prevents interrupt states from correct migration.

This initializes priority to 0xFF as the emulated XICS does.

Suggested-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 03:49:48 +01:00
Alexey Kardashevskiy
0f20ba62c3 target-ppc: spapr: e500: fix to use cpu_dt_id
This makes use of @cpu_dt_id and related API in:
1. emulated XICS hypercall handlers as they receive fixed CPU indexes;
2. XICS-KVM to enable in-kernel XICS on right CPU;
3. device-tree renderer.

This removes @cpu_index fixup as @cpu_dt_id is used instead so QEMU monitor
can accept command-line CPU indexes again.

This changes kvm_arch_vcpu_id() to use ppc_get_vcpu_dt_id() as at the moment
KVM CPU id and device tree ID are calculated using the same algorithm.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Mike Day <ncmike@ncultra.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-03-05 03:07:04 +01:00
Alexey Kardashevskiy
9554233c9b xics-kvm: enable irqfd for MSI
This enables IRQFD support for sPAPR. The feature decreases the latency
of interrupt handling.

To enable IRQFD for MSI, this sets kvm_gsi_direct_mapping to true which
enables direct MSI mapping.

To enable IRQFD for LSI (level triggered INTx interrupts), a PCI host bus
callback is required. The patch for that is coming next.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-25 23:25:47 +02:00
David Gibson
11ad93f681 xics-kvm: Support for in-kernel XICS interrupt controller
Recent (host) kernels support emulating the PAPR defined "XICS" interrupt
controller system within KVM.  This patch allows qemu to initialize and
configure the in-kernel XICS, and keep its state in sync with qemu's XICS
state as necessary.

This should give considerable performance improvements.  e.g. on a simple
IPI ping-pong test between hardware threads, using qemu XICS gives us
around 5,000 irqs/second, whereas the in-kernel XICS gives us around
70,000 irqs/s on the same hardware configuration.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[Mike Qiu <qiudayu@linux.vnet.ibm.com>: fixed mistype which caused ics_set_kvm_state() to fail]
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-25 23:25:47 +02:00