The Big QEMU Lock (BQL) has many names and they are confusing. The
actual QemuMutex variable is called qemu_global_mutex but it's commonly
referred to as the BQL in discussions and some code comments. The
locking APIs, however, are called qemu_mutex_lock_iothread() and
qemu_mutex_unlock_iothread().
The "iothread" name is historic and comes from when the main thread was
split into into KVM vcpu threads and the "iothread" (now called the main
loop thread). I have contributed to the confusion myself by introducing
a separate --object iothread, a separate concept unrelated to the BQL.
The "iothread" name is no longer appropriate for the BQL. Rename the
locking APIs to:
- void bql_lock(void)
- void bql_unlock(void)
- bool bql_locked(void)
There are more APIs with "iothread" in their names. Subsequent patches
will rename them. There are also comments and documentation that will be
updated in later patches.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Acked-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Clarify the behavior of TYPE_VFU_OBJECT when TYPE_REMOTE_MACHINE enables
the auto-shutdown property. Also, add notes to VFU_OBJECT_ERROR.
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
pci_bus_irqs() coupled together the assignment of pci_set_irq_fn and
pci_map_irq_fn to a PCI bus. This coupling gets in the way when the
pci_map_irq_fn is board-specific while the pci_set_irq_fn is device-
specific.
For example, both of QEMU's PIIX south bridge models have different
pci_map_irq_fn implementations which are board-specific rather than
device-specific. These implementations should therefore reside in board
code. The pci_set_irq_fn's, however, should stay in the device models
because they access memory internal to the model.
Factoring out pci_bus_map_irqs() from pci_bus_irqs() allows the
assignments to be decoupled, resolving the problem described above.
Note also how pci_vpb_realize() which gets touched in this commit
assigns different pci_map_irq_fn's depending on the board.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230109172347.1830-5-shentey@gmail.com>
[PMD: Factor out in vfu_object_set_bus_irq()]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The legacy function qdev_reset_all() performs a recursive reset,
starting from a qdev. However, it does not permit any of the devices
in the tree to use three-phase reset, because device reset goes
through the device_legacy_reset() function that only calls the single
DeviceClass::reset method.
Switch to using the device_cold_reset() function instead. This also
performs a recursive reset, where first the children are reset and
then finally the parent, but it uses the new (...in 2020...)
Resettable mechanism, which supports both the old style single-reset
method and also the new 3-phase reset handling.
This commit changes the five remaining uses of this function.
Commit created with:
sed -i -e 's/qdev_reset_all/device_cold_reset/g' hw/i386/xen/xen_platform.c hw/input/adb.c hw/remote/vfio-user-obj.c hw/s390x/s390-virtio-ccw.c hw/usb/dev-uas.c
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
include/qapi/error.h on ERRP_GUARD():
* It must be used when the function dereferences @errp or passes
* @errp to error_prepend(), error_vprepend(), or error_append_hint().
* It is safe to use even when it's not needed, but please avoid
* cluttering the source with useless code.
Clean up some of this clutter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221121085054.683122-3-armbru@redhat.com>
There were several different ways to deal with the situation where the
vector specified for a msix function is out of bound:
- early return a function and keep progresssing
- propagate the error to the caller
- mark msix unusable
- assert it is in bound
- just ignore
An out-of-bound vector should not be specified if the device
implementation is correct so let msix functions always assert that the
specified vector is in range.
An exceptional case is virtio-pci, which allows the guest to configure
vectors. For virtio-pci, it is more appropriate to introduce its own
checks because it is sometimes too late to check the vector range in
msix functions.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20220829083524.143640-1-akihiko.odaki@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Yuval Shaia <yuval.shaia.ml@gmail.com>
Signed-off-by: Akihiko Odaki <<a href="mailto:akihiko.odaki@daynix.com" target="_blank">akihiko.odaki@daynix.com</a>><br>