Kernel KVM virtualization development
 help / color / mirror / Atom feed
From: Andrew Jones <andrew.jones@linux.dev>
To: 何琼 <heqiong1557@phytium.com.cn>
Cc: kvm <kvm@vger.kernel.org>
Subject: Re: [kvm-unit-tests 1/1] arm64: microbench: Move the read of the count register and the ISB operation out of the while loop
Date: Wed, 1 Nov 2023 11:06:27 +0100	[thread overview]
Message-ID: <20231101-923f359769ccf8db69c25c4f@orel> (raw)
In-Reply-To: <7ac00102.1c5.18b89fcf84f.Coremail.heqiong1557@phytium.com.cn>

Hi,

It's quite hard to read this mail because of the formatting. Also, please
do not submit patches as attachments. Despite it being an attachment, I
took a look and it looks fine, but it's missing a signed-off-by.

Please resubmit with this mail as a cover-letter and formatted properly
with line wraps, etc. and the patch, as it's own message, in-reply-to the
cover letter. You may want to use git-send-email.

Thanks,
drew



On Wed, Nov 01, 2023 at 04:25:39PM +0800, 何琼 wrote:
> 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]#
> 
> 
> 
> 
> 
> 
> 
> 
> 

> From 518cd47c33fce60ef86ed66dfa9e904b66499933 Mon Sep 17 00:00:00 2001
> From: heqiong <heqiong1557@phytium.com.cn>
> 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
> 


  reply	other threads:[~2023-11-01 10:06 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-01  8:25 [kvm-unit-tests 1/1] arm64: microbench: Move the read of the count register and the ISB operation out of the while loop 何琼
2023-11-01 10:06 ` Andrew Jones [this message]
2023-11-01 11:04 ` Alexandru Elisei
2023-11-02  7:40   ` 回复: " 何琼
2023-11-02  7:59     ` Yi Liu
  -- strict thread matches above, loose matches on Subject: below --
2023-11-07  6:40 heqiong
2023-11-07  8:40 ` Andrew Jones
2023-11-07  9:07 ` Alexandru Elisei

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20231101-923f359769ccf8db69c25c4f@orel \
    --to=andrew.jones@linux.dev \
    --cc=heqiong1557@phytium.com.cn \
    --cc=kvm@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox