In irqfd mode, current code attempts to set a resamplefd whatever
the type of the IRQ. For an edge-sensitive IRQ this attempt fails
and as a consequence, the whole irqfd setup fails and we fall back
to the slow mode. This patch bypasses the resamplefd setting for
non level-sentive IRQs.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
unmask EventNotifier might not be initialized in case of edge
sensitive irq. Using EventNotifier pointers make life simpler to
handle the edge-sensitive irqfd setup.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
With current implementation, eventfd VFIO signaling is first set up and
then irqfd is setup, if supported and allowed.
This start sequence causes several issues with IRQ forwarding setup
which, if supported, is transparently attempted on irqfd setup:
IRQ forwarding setup is likely to fail if the IRQ is detected as under
injection into the guest (active at irqchip level or VFIO masked).
This currently always happens because the current sequence explicitly
VFIO-masks the IRQ before setting irqfd.
Even if that masking were removed, we couldn't prevent the case where
the IRQ is under injection into the guest.
So the simpler solution is to remove this 2-step startup and directly
attempt irqfd setup. This is what this patch does.
Also in case the eventfd setup fails, there is no reason to go farther:
let's abort.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The default should be to allow mmap and new drivers shouldn't need to
expose an option or set it to other than the allocation default in
their initfn. Take advantage of the experimental flag to change this
option to the correct polarity.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Minor cleanup.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This patch aims at optimizing IRQ handling using irqfd framework.
Instead of handling the eventfds on user-side they are handled on
kernel side using
- the KVM irqfd framework,
- the VFIO driver virqfd framework.
the virtual IRQ completion is trapped at interrupt controller
This removes the need for fast/slow path swap.
Overall this brings significant performance improvements.
Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Include linux/vfio.h after sys/ioctl.h, just like in hw/vfio/common.c.
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Message-id: 1434544500-22405-1-git-send-email-leon.alrae@imgtec.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
g_malloc0_n() is introduced since glib-2.24 while QEMU currently
requires glib-2.22. This may cause a link error on some distributions.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch adds the code requested to assign interrupts to
a guest. The interrupts are mediated through user handled
eventfds only.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Minimal VFIO platform implementation supporting register space
user mapping but not IRQ assignment.
Signed-off-by: Kim Phillips <kim.phillips@linaro.org>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
