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Message-ID: <371c84608bd10736de6b1a8abee3fd1d43664a9a.camel@gmail.com>
Subject: Re: [PATCH RFC bpf-next v6 1/6] bpf/helpers: introduce sleepable
 bpf_timers
From: Eduard Zingerman <eddyz87@gmail.com>
To: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: Benjamin Tissoires <bentiss@kernel.org>, Alexei Starovoitov
 <ast@kernel.org>,  Daniel Borkmann <daniel@iogearbox.net>, Andrii Nakryiko
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 Fomichev <sdf@google.com>, Hao Luo <haoluo@google.com>, Jiri Olsa
 <jolsa@kernel.org>,  Mykola Lysenko <mykolal@fb.com>, Shuah Khan
 <shuah@kernel.org>, bpf@vger.kernel.org,  linux-kernel@vger.kernel.org,
 linux-kselftest@vger.kernel.org
Date: Tue, 09 Apr 2024 00:17:38 +0300
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On Mon, 2024-04-08 at 19:20 +0200, Benjamin Tissoires wrote:

[...]

> That was my initial assumption too, but Alexei told me it was fine.
> And I think he is correct because kfree_rcu doesn't need the rcu_head
> to be initialized.
>=20
> So in the end, we initialize the memory as a work_struct, and when
> that work kicks in, we reuse that exact same memory as the rcu_head.
> This is fine because that work will never be reused.

Oh, I get it, thank you for explanation.

Thanks,
Eduard