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([2a01:4b00:bd1f:f500:f867:fc8a:5174:5755]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-43fe4e4d6casm4797952f8f.32.2026.04.17.08.16.34 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 17 Apr 2026 08:16:35 -0700 (PDT) Message-ID: <4c0e73e1-43c3-48a3-ab89-239fed7e6c23@gmail.com> Date: Fri, 17 Apr 2026 16:16:34 +0100 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC bpf-next v2 00/18] bpf: Introduce resizable hash map To: Herbert Xu Cc: Alexei Starovoitov , bpf , Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Martin Lau , Kernel Team , Eduard , Kumar Kartikeya Dwivedi , Mykyta Yatsenko References: <20260408-rhash-v2-0-3b3675da1f6e@meta.com> <96b6f76e-1dc9-4d54-9f92-8586796ef607@gmail.com> Content-Language: en-US From: Mykyta Yatsenko In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/17/26 7:54 AM, Herbert Xu wrote: > On Thu, Apr 16, 2026 at 04:10:35PM +0100, Mykyta Yatsenko wrote: >> >> There is a problem though is the get_next_key interface: >> >> int get_next_key(struct bpf_map *map, void *key, void *next_key) > > Any chance of changing the interface? > > If not then perhaps a better solution is to use a linked list > in conjunction with rhashtable. It'll cost a little bit of > extra memory, but really provides you with the ideal solution > for what you're trying to do. > > Cheers, Changing interface is practically not possible - this comes from the bpf syscall. Linked list solution: we probably can't afford it performance-wise, it's not worth it to pay for the linked list maintenance in insert/delete operations, to make traversals work well.