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Date:   Wed, 5 Oct 2022 11:07:07 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Xu Kuohai <xukuohai@huawei.com>
Cc:     Florent Revest <revest@chromium.org>,
        Mark Rutland <mark.rutland@arm.com>,
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Subject: Re: [PATCH bpf-next v2 0/4] Add ftrace direct call for arm64
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On Wed, 5 Oct 2022 22:54:15 +0800
Xu Kuohai <xukuohai@huawei.com> wrote:

> 1.3 attach bpf prog with with direct call, bpftrace -e 'kfunc:vfs_write {}'
> 
> # dd if=/dev/zero of=/dev/null count=1000000
> 1000000+0 records in
> 1000000+0 records out
> 512000000 bytes (512 MB, 488 MiB) copied, 1.72973 s, 296 MB/s
> 
> 
> 1.4 attach bpf prog with with indirect call, bpftrace -e 'kfunc:vfs_write {}'
> 
> # dd if=/dev/zero of=/dev/null count=1000000
> 1000000+0 records in
> 1000000+0 records out
> 512000000 bytes (512 MB, 488 MiB) copied, 1.99179 s, 257 MB/s

Can you show the implementation of the indirect call you used?

Thanks,

-- Steve