netdev - Question about concurrent accesses to an eBPF map

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Message-ID: <CANuct4v1GjHrkw8uwTdjzDWoq0ZVy6NY49TXT1QSO+d7eh9iCg@mail.gmail.com>
Date:   Wed, 9 Oct 2019 14:09:53 +0800
From:   Chen鹏 <mobemhit@...il.com>
To:     netdev@...r.kernel.org
Subject: Question about concurrent accesses to an eBPF map

Hi,

Now I have an eBPF program which adds or updates elements in an eBPF
map. Meanwhile, I have a user space application which reads and
deletes elements in the aforementioned eBPF map. For a specific
element in the eBPF map, if an update happens between the read and
delete, I will lose some data. I'm using 4.9.30 upstream kernel, and
I'm wondering if there is any mechanism in eBPF which can make the
"read and delete" an atomic operation.

Thanks in advance,
Paul