accel/tcg/tcg-accel-ops-rr: ensure fairness with icount

The round-robin scheduler will iterate over the CPU list with an
assigned budget until the next timer expiry and may exit early because
of a T

accel/tcg/tcg-accel-ops-rr: ensure fairness with icount

The round-robin scheduler will iterate over the CPU list with an
assigned budget until the next timer expiry and may exit early because
of a TB exit. This is fine under normal operation but with icount
enabled and SMP it is possible for a CPU to be starved of run time and
the system live-locks.

For example, booting a riscv64 platform with '-icount
shift=0,align=off,sleep=on -smp 2' we observe a livelock once the kernel
has timers enabled and starts performing TLB shootdowns. In this case
we have CPU 0 in M-mode with interrupts disabled sending an IPI to CPU
1. As we enter the TCG loop, we assign the icount budget to next timer
interrupt to CPU 0 and begin executing where the guest is sat in a busy
loop exhausting all of the budget before we try to execute CPU 1 which
is the target of the IPI but CPU 1 is left with no budget with which to
execute and the process repeats.

We try here to add some fairness by splitting the budget across all of
the CPUs on the thread fairly before entering each one. The CPU count
is cached on CPU list generation ID to avoid iterating the list on each
loop iteration. With this change it is possible to boot an SMP rv64
guest with icount enabled and no hangs.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Jamie Iles <quic_jiles@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427020925.51003-3-quic_jiles@quicinc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

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Clean up header guards that don't match their file name

Header guard symbols should match their file name to make guard
collisions less likely.

Cleaned up with scripts/clean-header-guards.pl, follo

Clean up header guards that don't match their file name

Header guard symbols should match their file name to make guard
collisions less likely.

Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220506134911.2856099-2-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[Change to generated file ebpf/rss.bpf.skeleton.h backed out]

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accel: replace struct CpusAccel with AccelOpsClass

This will allow us to centralize the registration of
the cpus.c module accelerator operations (in accel/accel-softmmu.c),
and trigger it automatica

accel: replace struct CpusAccel with AccelOpsClass

This will allow us to centralize the registration of
the cpus.c module accelerator operations (in accel/accel-softmmu.c),
and trigger it automatically using object hierarchy lookup from the
new accel_init_interfaces() initialization step, depending just on
which accelerators are available in the code.

Rename all tcg-cpus.c, kvm-cpus.c, etc to tcg-accel-ops.c,
kvm-accel-ops.c, etc, matching the object type names.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20210204163931.7358-18-cfontana@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,virtio,pci: fixes, features,code removal

Fixes all over the place.
Ability to control ACPI OEM ID's.
Ability to control

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pc,virtio,pci: fixes, features,code removal

Fixes all over the place.
Ability to control ACPI OEM ID's.
Ability to control rom BAR size.
Removal of deprecated pc machine types.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 05 Feb 2021 13:54:32 GMT
# gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
tests/acpi: disallow updates for expected data files
tests/acpi: update expected data files
tests/acpi: add OEM ID and OEM TABLE ID test
acpi: use constants as strncpy limit
acpi: Permit OEM ID and OEM table ID fields to be changed
tests/acpi: allow updates for expected data files
vhost: Check for valid vdev in vhost_backend_handle_iotlb_msg
hw/virtio/virtio-balloon: Remove the "class" property
hw/i386: Remove the deprecated pc-1.x machine types
vhost: Unbreak SMMU and virtio-iommu on dev-iotlb support
virtio-pmem: add trace events
virtio: Add corresponding memory_listener_unregister to unrealize
virtio-mmio: fix guest kernel crash with SHM regions
virtio: move 'use-disabled-flag' property to hw_compat_4_2
pci: add romsize property
pci: reject too large ROMs

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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