We weren't using cs_base in the hash calculations before. Since the
arm front end moved a chunk of flags in a378206a20 (target/arm: Move
mode specific TB flags to tb->cs_base) they comprise of an important
part of the execution state.
Widen the tb_hash_func to include cs_base and expand to qemu_xxhash8()
to accommodate it.
My initial benchmark shows very little difference in the
runtime.
Before:
armhf
➜ hyperfine -w 2 -m 20 "./arm-softmmu/qemu-system-arm -cpu cortex-a15 -machine
type=virt,highmem=off -display none -m 2048 -serial mon:stdio -netdev
user,id=unet,hostfwd=tcp::2222-:22 -device virtio-net-pci,netdev=unet -device
virtio-scsi-pci -blockdev
driver=raw,node-name=hd,discard=unmap,file.driver=host_device,file.filename=/dev/zen-disk/debian-bullseye-armhf
-device scsi-hd,drive=hd -smp 4 -kernel
/home/alex/lsrc/linux.git/builds/arm/arch/arm/boot/zImage -append 'console=ttyAMA0
root=/dev/sda2 systemd.unit=benchmark.service' -snapshot"
Benchmark 1: ./arm-softmmu/qemu-system-arm -cpu cortex-a15 -machine
type=virt,highmem=off -display none -m 2048 -serial mon:stdio -netdev
user,id=unet,hostfwd=tcp::2222-:22 -device virtio-net-pci,netdev=unet -device
virtio-scsi-pci -blockdev
driver=raw,node-name=hd,discard=unmap,file.driver=host_device,file.filename=/dev/zen-disk/debian-bullseye-armhf
-device scsi-hd,drive=hd -smp 4 -kernel
/home/alex/lsrc/linux.git/builds/arm/arch/arm/boot/zImage -append
'console=ttyAMA0 root=/dev/sda2 systemd.unit=benchmark.service' -snapshot
Time (mean ± σ): 24.627 s ± 2.708 s [User: 34.309 s, System: 1.797 s]
Range (min … max): 22.345 s … 29.864 s 20 runs
arm64
➜ hyperfine -w 2 -n 20 "./qemu-system-aarch64 -cpu max,pauth-impdef=on -machine
type=virt,virtualization=on,gic-version=3 -display none -serial mon:stdio -netdev
user,id=unet,hostfwd=tcp::2222-:22,hostfwd=tcp::1234-:1234 -device
virtio-net-pci,netdev=unet -device virtio-scsi-pci -blockdev
driver=raw,node-name=hd,discard=unmap,file.driver=host_device,file.filename=/dev/zen-disk/debian-bullseye-arm64
-device scsi-hd,drive=hd -smp 4 -kernel
~/lsrc/linux.git/builds/arm64/arch/arm64/boot/Image.gz -append 'console=ttyAMA0
root=/dev/sda2 systemd.unit=benchmark-pigz.service' -snapshot"
Benchmark 1: 20
Time (mean ± σ): 62.559 s ± 2.917 s [User: 189.115 s, System: 4.089
s]
Range (min … max): 59.997 s … 70.153 s 10 runs
After:
armhf
Benchmark 1: ./arm-softmmu/qemu-system-arm -cpu cortex-a15 -machine
type=virt,highmem=off -display none -m 2048 -serial mon:stdio -netdev
user,id=unet,hostfwd=tcp::2222-:22 -device virtio-net-pci,netdev=unet -device
virtio-scsi-pci -blockdev
driver=raw,node-name=hd,discard=unmap,file.driver=host_device,file.filename=/dev/zen-disk/debian-bullseye-armhf
-device scsi-hd,drive=hd -smp 4 -kernel
/home/alex/lsrc/linux.git/builds/arm/arch/arm/boot/zImage -append
'console=ttyAMA0 root=/dev/sda2 systemd.unit=benchmark.service' -snapshot
Time (mean ± σ): 24.223 s ± 2.151 s [User: 34.284 s, System: 1.906 s]
Range (min … max): 22.000 s … 28.476 s 20 runs
arm64
hyperfine -w 2 -n 20 "./qemu-system-aarch64 -cpu max,pauth-impdef=on -machine
type=virt,virtualization=on,gic-version=3 -display none -serial mon:stdio -netdev
user,id=unet,hostfwd=tcp::2222-:22,hostfwd=tcp::1234-:1234 -device
virtio-net-pci,netdev=unet -device virtio-scsi-pci -blockdev
driver=raw,node-name=hd,discard=unmap,file.driver=host_device,file.filename=/dev/zen-disk/debian-bullseye-arm64
-device scsi-hd,drive=hd -smp 4 -kernel
~/lsrc/linux.git/builds/arm64/arch/arm64/boot/Image.gz -append 'console=ttyAMA0
root=/dev/sda2 systemd.unit=benchmark-pigz.service' -snapshot"
Benchmark 1: 20
Time (mean ± σ): 62.769 s ± 1.978 s [User: 188.431 s, System: 5.269
s]
Range (min … max): 60.285 s … 66.868 s 10 runs
Signed-off-by: Alex Bennée<alex.bennee@linaro.org>
Message-Id:<20230523125000.3674739-11-alex.bennee@linaro.org>