hi,
This patch mainly includes the following content.
Reducing the impact of the cntvct_el0 register and isb() operation on microbenchmark test results to improve testing accuracy and reduce latency in test results.
Test in kunpeng920,
Test results before applying the patch:
[root@localhost tests]# ./micro-bench
BUILD_HEAD=767629ca
Test marked not to be run by default, are you sure (y/N)? y
timeout -k 1s --foreground 90s numactl -C 0-3 -m 0 /usr/libexec/qemu-kvm -nodefaults -machine virt,gic-version=host -accel kvm -cpu host -device virtio-serial-device -device virtconsole,chardev=ctd -chardev testdev,id=ctd -device pci-testdev -display none -serial stdio -kernel /tmp/tmp.y4c4YHIprP -smp 2 # -initrd /tmp/tmp.KLLmjTuq2d
Timer Frequency 100000000 Hz (Output in microseconds)
name total ns avg ns
--------------------------------------------------------------------------------------------
hvc 26774980.0 408.0
mmio_read_user 151183350.0 2306.0
mmio_read_vgic 41849830.0 638.0
eoi 1735610.0 26.0
ipi 111260770.0 1697.0
ipi_hw test skipped
lpi 142124570.0 2168.0
timer_10ms 466660.0 1822.0
EXIT: STATUS=1
PASS micro-bench
[root@localhost tests]#
Test results after applying the patch:
[root@localhost kvm-unit-tests]# cd tests/
[root@localhost tests]# ./micro-bench
BUILD_HEAD=767629ca
Test marked not to be run by default, are you sure (y/N)? y
timeout -k 1s --foreground 90s numactl -C 0-3 -m 0 /usr/libexec/qemu-kvm -nodefaults -machine virt,gic-version=host -accel kvm -cpu host -device virtio-serial-device -device virtconsole,chardev=ctd -chardev testdev,id=ctd -device pci-testdev -display none -serial stdio -kernel /tmp/tmp.FiBID6KLxB -smp 2 # -initrd /tmp/tmp.oSKZeugleF
Timer Frequency 100000000 Hz (Output in microseconds)
name total ns avg ns
--------------------------------------------------------------------------------------------
hvc 26721040.0 407.0
mmio_read_user 150824560.0 2301.0
mmio_read_vgic 41845380.0 638.0
eoi 1109180.0 16.0
ipi 106062150.0 1618.0
ipi_hw test skipped
lpi 141700760.0 2162.0
timer_10ms 470870.0 1839.0
EXIT: STATUS=1
PASS micro-bench
[root@localhost tests]#
Test in phytium S2500,
Test results before applying the patch:
[root@primecontroller tests]# ./micro-bench
BUILD_HEAD=518cd47c
Test marked not to be run by default, are you sure (y/N)? y
timeout -k 1s --foreground 90s numactl -C 0-3 -m 0 /usr/local/bin/qemu-system-aarch64 -nodefaults -machine virt,gic-version=host -accel kvm -cpu host -device virtio-serial-device -device virtconsole,chardev=ctd -chardev testdev,id=ctd -device pci-testdev -display none -serial stdio -kernel /tmp/tmp.lrJJqSuLmN -smp 2 # -initrd /tmp/tmp.s18C3k2jfO
Timer Frequency 50000000 Hz (Output in microseconds)
name total ns avg ns
--------------------------------------------------------------------------------------------
hvc 100668780.0 1536.0
mmio_read_user 472806800.0 7214.0
mmio_read_vgic 140912320.0 2150.0
eoi 2972280.0 45.0
ipi 326332780.0 4979.0
ipi_hw test skipped
lpi 359226600.0 5481.0
timer_10ms 1271960.0 4968.0
EXIT: STATUS=1
PASS micro-bench
[root@primecontroller tests]#
Test results after applying the patch:
[root@primecontroller tests]# ./micro-bench
BUILD_HEAD=518cd47c
Test marked not to be run by default, are you sure (y/N)? y
timeout -k 1s --foreground 90s numactl -C 0-3 -m 0 /usr/local/bin/qemu-system-aarch64 -nodefaults -machine virt,gic-version=host -accel kvm -cpu host -device virtio-serial-device -device virtconsole,chardev=ctd -chardev testdev,id=ctd -device pci-testdev -display none -serial stdio -kernel /tmp/tmp.IsEtcs1W1g -smp 2 # -initrd /tmp/tmp.885IpeoGw4
Timer Frequency 50000000 Hz (Output in microseconds)
name total ns avg ns
--------------------------------------------------------------------------------------------
hvc 99490080.0 1518.0
mmio_read_user 474781300.0 7244.0
mmio_read_vgic 140470760.0 2143.0
eoi 1693260.0 25.0
ipi 323551200.0 4936.0
ipi_hw test skipped
lpi 355690620.0 5427.0
timer_10ms 1318540.0 5150.0
EXIT: STATUS=1
PASS micro-bench
[root@primecontroller tests]#
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From 518cd47c33fce60ef86ed66dfa9e904b66499933 Mon Sep 17 00:00:00 2001
From: heqiong <heqiong1557@xxxxxxxxxxxxxx>
Date: Wed, 1 Nov 2023 15:06:28 +0800
Subject: [kvm-unit-tests 1/1] arm64: microbench: Move the read of the count
register and the ISB operation out of the while loop
Reducing the impact of the cntvct_el0 register and isb() operation
on microbenchmark test results to improve testing accuracy and reduce
latency in test results.
---
arm/micro-bench.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index fbe59d03..ee5b9ca0 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -346,17 +346,18 @@ static void loop_test(struct exit_test *test)
}
}
+ start = read_sysreg(cntpct_el0);
+ isb();
while (ntimes < test->times && total_ns.ns < NS_5_SECONDS) {
- isb();
- start = read_sysreg(cntvct_el0);
test->exec();
- isb();
- end = read_sysreg(cntvct_el0);
ntimes++;
- total_ticks += (end - start);
- ticks_to_ns_time(total_ticks, &total_ns);
}
+ isb();
+ end = read_sysreg(cntpct_el0);
+
+ total_ticks = end - start;
+ ticks_to_ns_time(total_ticks, &total_ns);
if (test->post) {
test->post(ntimes, &total_ticks);
--
2.31.1
