bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Joanne Koong <joannekoong@fb.com>,
	Martin KaFai Lau <kafai@fb.com>, bpf <bpf@vger.kernel.org>,
	Kernel Team <Kernel-team@fb.com>
Subject: Re: [PATCH v3 bpf-next 1/5] bpf: Add bloom filter map implementation
Date: Tue, 28 Sep 2021 20:17:15 -0700	[thread overview]
Message-ID: <20210929031715.wvicuaf6iixm7xsb@ast-mbp.dhcp.thefacebook.com> (raw)
In-Reply-To: <CAEf4BzbH8v2m4tJEz2hFU+PGxMxP6QrFXcRmD3ESiQi_jqBbtw@mail.gmail.com>

On Tue, Sep 28, 2021 at 05:14:55PM -0700, Andrii Nakryiko wrote:
> 
> So for Bloom filter you get performance advantage from a dedicated map
> (due to having just 1 helper call to do N hashing operations). For
> pure bitset, there seems to be little benefit at all because it is
> basically ARRAY.

I brought up bitset only as an idea to make bloomfilter map a bit more
generic and was looking for feedback whether to call the new map
"bitset that allows bloomfilter operations" or call it
"bloomfilter that simplifies to bitset" with nr_hashes=0.

It sounds that using bloomfilter as a base name fits better.

> I haven't found SPDX header or any mention of GPL in
> include/linux/jhash.h, so I assumed someone can just copy paste the
> code (given the references to public domain). Seems like that's not
> the case? Just curious about implications, license-wise, if there is
> no SPDX? Is it still considered GPL?

I believe so. Every project that copy pasted jhash from the kernel
add SPDX gpl-2 to its source.

  reply	other threads:[~2021-09-29  3:17 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-21 21:02 [PATCH v3 bpf-next 0/5] Implement bloom filter map Joanne Koong
2021-09-21 21:02 ` [PATCH v3 bpf-next 1/5] bpf: Add bloom filter map implementation Joanne Koong
2021-09-21 23:44   ` Andrii Nakryiko
2021-09-22 19:06     ` Joanne Koong
2021-09-22 19:38       ` Martin KaFai Lau
2021-09-22 20:52         ` Andrii Nakryiko
2021-09-22 22:08           ` Martin KaFai Lau
2021-09-22 23:07             ` Andrii Nakryiko
2021-09-23  1:28               ` Martin KaFai Lau
2021-09-23 18:42                 ` Andrii Nakryiko
2021-09-23 19:42                   ` Martin KaFai Lau
2021-09-23 20:30                     ` Alexei Starovoitov
2021-09-23 21:12                       ` Andrii Nakryiko
2021-09-23 22:28                         ` Joanne Koong
2021-09-23 23:46                           ` Martin KaFai Lau
2021-09-24  2:23                           ` Andrii Nakryiko
2021-09-24 16:32                             ` Joanne Koong
2021-09-24 23:12                               ` Andrii Nakryiko
2021-09-27 16:41                                 ` Alexei Starovoitov
2021-09-27 21:14                                   ` Andrii Nakryiko
2021-09-27 23:51                                     ` Alexei Starovoitov
2021-09-28  0:36                                       ` Andrii Nakryiko
2021-09-28 16:21                                         ` Alexei Starovoitov
     [not found]                                           ` <aa967ed2-a958-f995-3a09-bbd6b6e775d4@fb.com>
2021-09-28 23:54                                             ` Andrii Nakryiko
2021-09-29  1:54                                               ` Joanne Koong
2021-09-29  0:14                                           ` Andrii Nakryiko
2021-09-29  3:17                                             ` Alexei Starovoitov [this message]
2021-09-29  3:38                                               ` Joanne Koong
2021-09-28  1:09                                 ` Martin KaFai Lau
2021-09-22 20:44       ` Andrii Nakryiko
2021-09-21 21:02 ` [PATCH v3 bpf-next 2/5] libbpf: Allow the number of hashes in bloom filter maps to be configurable Joanne Koong
2021-09-21 22:24   ` Joanne Koong
2021-09-22 23:14     ` Andrii Nakryiko
2021-09-21 23:57   ` Andrii Nakryiko
2021-09-21 21:02 ` [PATCH v3 bpf-next 3/5] selftests/bpf: Add bloom filter map test cases Joanne Koong
2021-09-21 21:02 ` [PATCH v3 bpf-next 4/5] bpf/benchs: Add benchmark test for bloom filter maps Joanne Koong
2021-09-21 21:02 ` [PATCH v3 bpf-next 5/5] bpf/benchs: Add benchmarks for comparing hashmap lookups with vs. without bloom filter Joanne Koong

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=20210929031715.wvicuaf6iixm7xsb@ast-mbp.dhcp.thefacebook.com \
    --to=alexei.starovoitov@gmail.com \
    --cc=Kernel-team@fb.com \
    --cc=andrii.nakryiko@gmail.com \
    --cc=bpf@vger.kernel.org \
    --cc=joannekoong@fb.com \
    --cc=kafai@fb.com \
    /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;
as well as URLs for NNTP newsgroup(s).