All of lore.kernel.org
 help / color / mirror / Atom feed
From: Joanne Koong <joannekoong@fb.com>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: 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 20:38:45 -0700	[thread overview]
Message-ID: <c74f5df1-4953-29ca-2217-e63c3f112463@fb.com> (raw)
In-Reply-To: <20210929031715.wvicuaf6iixm7xsb@ast-mbp.dhcp.thefacebook.com>

On 9/28/21 8:17 PM, Alexei Starovoitov wrote:

> 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 am in favor of calling the new map "bitset that allows bloom filter 
operations"
and having the map be BPF_MAP_TYPE_BITSET everywhere.
To me that is more intuitive since the bloom filter is based on top of a 
bitset.
And I think more people will generally be using bitsets than the bloom 
filter.
Additionally, for users who don't know or care what a bloom filter is, they
might skip this map type altogether and not realize it also can be used as
a bitset.
>> 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  3:38 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
2021-09-29  3:38                                               ` Joanne Koong [this message]
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=c74f5df1-4953-29ca-2217-e63c3f112463@fb.com \
    --to=joannekoong@fb.com \
    --cc=Kernel-team@fb.com \
    --cc=alexei.starovoitov@gmail.com \
    --cc=andrii.nakryiko@gmail.com \
    --cc=bpf@vger.kernel.org \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.