Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into per-bucket bit spinlock

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From	Ming Lei <tom.leiming@gmail.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into per-bucket bit spinlock
Date	Sat, 26 Dec 2015 10:00:03 +0100
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On Fri, Dec 18, 2015 at 2:20 PM, Alexei Starovoitov
<alexei.starovoitov@gmail.com> wrote:
> On Wed, Dec 16, 2015 at 02:58:08PM +0800, Ming Lei wrote:
>> On Wed, Dec 16, 2015 at 1:01 PM, Yang Shi <shy828301@gmail.com> wrote:
>>
>> >
>> > I recalled Steven confirmed raw_spin_lock has the lockdep benefit too in the
>> > patch review for changing to raw lock.
>> >
>> > Please check this thread out
>> >  http://lists.openwall.net/netdev/2015/10/31/7
>>
>> OK, looks I was wrong about the lockdep benifit, :-(
>>
>> But for this lock, I think lockdep isn't such important, because it is the
>> intermost lock, and it can be used just for protecting the bucket list
>> and nothing else need to be covered.
>
> I still think that overhead of normal spinlock per bucket is acceptable.
> Makes the whole thing much easier to read.

OK, let's use per-bucket spinlock first.

--
Ming Lei
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[PATCH 4/6] bpf: hash: convert per-hashtable lock into per-bucket bit spinlock Ming Lei <tom.leiming@gmail.com> - 2015-12-15 12:30 +0100
  Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into  per-bucket bit spinlock Alexei Starovoitov <alexei.starovoitov@gmail.com> - 2015-12-16 00:00 +0100
    Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into per-bucket  bit spinlock Ming Lei <tom.leiming@gmail.com> - 2015-12-16 04:00 +0100
      Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into per-bucket  bit spinlock Ming Lei <tom.leiming@gmail.com> - 2015-12-16 08:00 +0100
        Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into  per-bucket bit spinlock Alexei Starovoitov <alexei.starovoitov@gmail.com> - 2015-12-18 07:30 +0100
          Re: [PATCH 4/6] bpf: hash: convert per-hashtable lock into per-bucket  bit spinlock Ming Lei <tom.leiming@gmail.com> - 2015-12-26 10:00 +0100

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