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Reply-To: noloader@gmail.com
From:   Jeffrey Walton <noloader@gmail.com>
Date:   Thu, 4 Aug 2022 12:08:00 -0400
Message-ID: <CAH8yC8nwHPMtsHHbkvUYrqjWBBs6WtuaFKjXpMP5cSnp+AJyKg@mail.gmail.com>
Subject: Re: [PATCH RFC v1] random: implement getrandom() in vDSO
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        X86 ML <x86@kernel.org>
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On Thu, Aug 4, 2022 at 11:40 AM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> On Wed, Aug 03, 2022 at 12:27:43AM +0200, Thomas Gleixner wrote:
> > Jason!
>
>  ...
> > Vs. the storage problem. That yells TLS, but that makes your process
> > wide sharing moot, which might not be the worst of all things IMO.
>
> Yea, TLS is what we want here. The `void *state` argument thing is meant
> for this. You allocate an array of states using that alloc function, and
> then you divvy them up per-thread.

I think it would be wise to give each thread its own state. It will
simplify locking and help avoid contention.

Jeff