The thread pool regulates itself: when idle, it kills threads until
empty, when in demand, it creates new threads until full. This behaviour
doesn't play well with latency sensitive workloads where the price of
creating a new thread is too high. For example, when paired with qemu's
'-mlock', or using safety features like SafeStack, creating a new thread
has been measured take multiple milliseconds.
In order to mitigate this let's introduce a new 'EventLoopBase'
property to set the thread pool size. The threads will be created during
the pool's initialization or upon updating the property's value, remain
available during its lifetime regardless of demand, and destroyed upon
freeing it. A properly characterized workload will then be able to
configure the pool to avoid any latency spikes.
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20220425075723.20019-4-nsaenzju@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
'event-loop-base' provides basic property handling for all 'AioContext'
based event loops. So let's define a new 'MainLoopClass' that inherits
from it. This will permit tweaking the main loop's properties through
qapi as well as through the command line using the '-object' keyword[1].
Only one instance of 'MainLoopClass' might be created at any time.
'EventLoopBaseClass' learns a new callback, 'can_be_deleted()' so as to
mark 'MainLoop' as non-deletable.
[1] For example:
-object main-loop,id=main-loop,aio-max-batch=<value>
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20220425075723.20019-3-nsaenzju@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Introduce the 'event-loop-base' abstract class, it'll hold the
properties common to all event loops and provide the necessary hooks for
their creation and maintenance. Then have iothread inherit from it.
EventLoopBaseClass is defined as user creatable and provides a hook for
its children to attach themselves to the user creatable class 'complete'
function. It also provides an update_params() callback to propagate
property changes onto its children.
The new 'event-loop-base' class will live in the root directory. It is
built on its own using the 'link_whole' option (there are no direct
function dependencies between the class and its children, it all happens
trough 'constructor' magic). And also imposes new compilation
dependencies:
qom <- event-loop-base <- blockdev (iothread.c)
And in subsequent patches:
qom <- event-loop-base <- qemuutil (util/main-loop.c)
All this forced some amount of reordering in meson.build:
- Moved qom build definition before qemuutil. Doing it the other way
around (i.e. moving qemuutil after qom) isn't possible as a lot of
core libraries that live in between the two depend on it.
- Process the 'hw' subdir earlier, as it introduces files into the
'qom' source set.
No functional changes intended.
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20220425075723.20019-2-nsaenzju@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Introduce new boolean 'kernel-hashes' option on the sev-guest object.
It will be used to to decide whether to add the hashes of
kernel/initrd/cmdline to SEV guest memory when booting with -kernel.
The default value is 'off'.
Signed-off-by: Dov Murik <dovmurik@linux.ibm.com>
Acked-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Add special feature 'unstable' everywhere the name starts with 'x-',
except for InputBarrierProperties member x-origin and
MemoryBackendProperties member x-use-canonical-path-for-ramblock-id,
because these two are actually stable.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-3-armbru@redhat.com>
Some of the ObjectType entries already depend on CONFIG_* switches.
Some others also only make sense with certain configurations, but
are currently always listed in the ObjectType enum. Let's make them
depend on the correpsonding CONFIG_* switches, too, so that upper
layers (like libvirt) have a better way to determine which features
are available in QEMU.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210928160232.432980-1-thuth@redhat.com>
[Do the same for MemoryBackendEpcProperties. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add the new 'memory-backend-epc' user creatable QOM object in
the ObjectOptions to support SGX since v6.1, or the sgx backend
object cannot bootup.
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20210719112136.57018-4-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Change the 'if' condition strings to be C-agnostic. It will accept
'[A-Z][A-Z0-9_]*' identifiers. This allows to express configuration
conditions in other languages (Rust or Python for ex) or other more
suitable forms.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: John Snow <jsnow@redhat.com>
Message-Id: <20210804083105.97531-11-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased with semantic conflict in redefined-event.json]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The `aio-max-batch` parameter will be propagated to AIO engines
and it will be used to control the maximum number of queued requests.
When there are in queue a number of requests equal to `aio-max-batch`,
the engine invokes the system call to forward the requests to the kernel.
This parameter allows us to control the maximum batch size to reduce
the latency that requests might accumulate while queued in the AIO
engine queue.
If `aio-max-batch` is equal to 0 (default value), the AIO engine will
use its default maximum batch size value.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20210721094211.69853-3-sgarzare@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Let's provide a way to control the use of RAM_NORESERVE via memory
backends using the "reserve" property which defaults to true (old
behavior).
Only Linux currently supports clearing the flag (and support is checked at
runtime, depending on the setting of "/proc/sys/vm/overcommit_memory").
Windows and other POSIX systems will bail out with "reserve=false".
The target use case is virtio-mem, which dynamically exposes memory
inside a large, sparse memory area to the VM. This essentially allows
avoiding to set "/proc/sys/vm/overcommit_memory == 0") when using
virtio-mem and also supporting hugetlbfs in the future.
As really only Linux implements RAM_NORESERVE right now, let's expose
the property only with CONFIG_LINUX. Setting the property to "false"
will then only fail in corner cases -- for example on very old kernels
or when memory overcommit was completely disabled by the admin.
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210510114328.21835-11-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The qtest server right now can only be created using the -qtest
and -qtest-log options. Allow an alternative way to create it
using "-object qtest,chardev=...,log=...".
This is part of the long term plan to make more (or all) of
QEMU configurable through QMP and preconfig mode.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Creating and destroying QOM objects does not require a fully constructed
machine. Allow running object-add and object-del before machine
initialization has concluded.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The ObjectType enum and ObjectOptions are included from qapi-types-qom.h
into common code. We should not use target-specific config switches like
CONFIG_VIRTIO_CRYPTO here, since this is not defined in common code and
thus the enum will look differently between common and target specific
code. For this case, it's hopefully enough to check for CONFIG_VHOST_CRYPTO
only (which is a host specific config switch, i.e. it's the same on all
targets).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210412160710.639800-1-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
ObjectType and ObjectOptions are defined in a target-independent file,
therefore they do not have access to target-specific configuration
symbols such as CONFIG_PSERIES or CONFIG_SEV. For this reason,
pef-guest and sev-guest are currently omitted when compiling the
generated QAPI files. In addition, this causes ObjectType to have
different definitions depending on the file that is including
qapi-types-qom.h (currently this is not causing any issues, but it
is wrong).
Define the two enum entries and the SevGuestProperties type
unconditionally to avoid the issue. We do not expect to have
many target-dependent user-creatable classes, so it is not
particularly problematic.
Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This converts object-add from 'gen': false to the ObjectOptions QAPI
type. As an immediate benefit, clients can now use QAPI schema
introspection for user creatable QOM objects.
It is also the first step towards making the QAPI schema the only
external interface for the creation of user creatable objects. Once all
other places (HMP and command lines of the system emulator and all
tools) go through QAPI, too, some object implementations can be
simplified because some checks (e.g. that mandatory options are set) are
already performed by QAPI, and in another step, QOM boilerplate code
could be generated from the schema.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the x-remote-object
object.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the input-* objects.
ui.json cannot be included in qom.json because the storage daemon can't
use it, so move GrabToggleKeys to common.json.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the objects implementing
the confidential-guest-support interface.
pef-guest and s390x-pv-guest don't have any properties, so they only
need to be added to the ObjectType enum without adding a new branch to
ObjectOptions.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the pr-manager-helper
object.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the filter-* objects.
Some parts of the interface (in particular NetfilterProperties.position)
are very unusual for QAPI, but for now just describe the existing
interface.
net.json can't be included in qom.json because the storage daemon
doesn't have it. NetFilterDirection is still required in the new object
property definitions in qom.json, so move this enum to common.json.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the colo-compare object.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the can-* objects.
can-bus doesn't have any properties, so it only needs to be added to the
ObjectType enum without adding a new branch to ObjectOptions.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the tls-* objects.
The 'loaded' property doesn't seem to make sense as an external
interface: It is automatically set to true in ucc->complete, and
explicitly setting it to true earlier just means that additional options
will be silently ignored.
In other words, the 'loaded' property is useless. Mark it as deprecated
in the schema from the start.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the secret* objects.
The 'loaded' property doesn't seem to make sense as an external
interface: It is automatically set to true in ucc->complete, and
explicitly setting it to true earlier just means that additional options
will be silently ignored.
In other words, the 'loaded' property is useless. Mark it as deprecated
in the schema from the start.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the throttle-group object.
The only purpose of the x-* properties is to make the nested options in
'limits' available for a command line parser that doesn't support
structs. Any parser that will use the QAPI schema will supports structs,
though, so they will not be needed in the schema in the future.
To keep the conversion straightforward, add them to the schema anyway.
We can then remove the options and adjust documentation, test cases etc.
in a separate patch.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the rng-* objects.
The 'opened' property doesn't seem to make sense as an external
interface: It is automatically set to true in ucc->complete, and
explicitly setting it to true earlier just means that trying to set
additional options will result in an error. After the property has once
been set to true (i.e. when the object construction has completed), it
can never be reset to false. In other words, the 'opened' property is
useless. Mark it as deprecated in the schema from the start.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the memory-backend-*
objects.
HostMemPolicy has to be moved to an include file that can be used by the
storage daemon, too, because ObjectOptions must be the same in all
binaries if we don't want to compile the whole code multiple times.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the dbus-vmstate object.
A list represented as a comma separated string is clearly not very
QAPI-like, but for now just describe the existing interface.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the cryptodev-* objects.
These interfaces have some questionable aspects (cryptodev-backend is
really an abstract base class without function, and the queues option
only makes sense for cryptodev-vhost-user), but as the goal is to
represent the existing interface in QAPI, leave these things in place.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
This adds a QAPI schema for the properties of the authz-* objects.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Acked-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Add an ObjectOptions union that will eventually describe the options of
all user creatable object types. As unions can't exist without any
branches, also add the first object type.
This adds a QAPI schema for the properties of the iothread object.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The option has been deprecated in QEMU 5.0, remove it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The various schemas included in QEMU use a JSON-based format which
is, however, strictly speaking not valid JSON.
As a consequence, when vim tries to apply syntax highlight rules
for JSON (as guessed from the file name), the result is an unreadable
mess which mostly consist of red markers pointing out supposed errors
in, well, pretty much everything.
Using Python syntax highlighting produces much better results, and
in fact these files already start with specially-formatted comments
that instruct Emacs to process them as if they were Python files.
This commit adds the equivalent special comments for vim.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Message-Id: <20200729185024.121766-1-abologna@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Mapping object-add to the command line as is doesn't result in nice
syntax because of the nesting introduced with 'props'. This becomes
nicer and more consistent with device_add and netdev_add when we accept
properties for the object on the top level instead.
'props' is still accepted after this patch, but marked as deprecated.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200224143008.13362-8-kwolf@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The current doc generation doesn't care much about indentation levels,
but we would like to switch to an rST format, and rST does care about
indentation.
Make the doc comments more strongly consistent about indentation
for multiline constructs like:
@arg: description line 1
description line 2
Returns: line one
line 2
so that there is always exactly one space after the colon, and
subsequent lines align with the first.
This commit is a purely whitespace change, and it does not alter the
generated .texi files (because the texi generation code strips away
all the extra whitespace). This does mean that we end up with some
over-length lines.
Note that when the documentation for an argument fits on a single
line like this:
@arg: one line only
then stray extra spaces after the ':' don't affect the rST output, so
I have not attempted to methodically fix them, though the preference
is a single space here too.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200213175647.17628-10-peter.maydell@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Report the default value associated with a property.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-26-marcandre.lureau@redhat.com>
[Report it as type "any", not string. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move commands object-add, object-del, qom-get, qom-list,
qom-list-properties, qom-list-types, and qom-set with their types from
misc.json to new qom.json.
Move commands device-list-properties, device_add, device-del, and
event DEVICE_DELETED from misc.json to new qdev.json.
Add both new files to MAINTAINERS section QOM.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190619201050.19040-5-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[Straightforwardly updated for "MAINTAINERS: Make section "QOM" cover
qdev as well"]
Nicolas Saenz Julienne
Dov Murik
Markus Armbruster
Thomas Huth
Yang Zhong
Marc-André Lureau
Stefano Garzarella
David Hildenbrand
Paolo Bonzini
Michael Tokarev
Kevin Wolf
Andrea Bolognani
Peter Maydell