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From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To: Anup Patel <apatel@ventanamicro.com>
Cc: Anup Patel <anup@brainfault.org>, Palmer Dabbelt <palmer@dabbelt.com>,
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 <ajones@ventanamicro.com>
Subject: Re: [PATCH v12 00/25] Linux RISC-V AIA Support
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Date: Wed, 07 Feb 2024 13:55:39 +0100
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Bj=C3=B6rn T=C3=B6pel <bjorn@kernel.org> writes:

>>> Hmm, seems like we're talking past each other, or at least I get the
>>> feeling I can't get my opinions out right. I'll try to do a quick PoC,
>>> to show you what I mean. That's probably easier than just talking about
>>> it. ...and maybe I'll come realizing I'm all wrong!
>>
>> I suggest to wait for my v13 and try something on top of that
>> otherwise we might duplicate efforts.
>
> OK!

I did some really rough code sketching, and I'm confident that you can
get rid of all ids_enabled_bitmap, hwirqs_used_bitmap, and the
corresponding functions/locks. I'd say one lock is enough, and the key
is having the per-cpu imsic_local_priv.vectors change from struct
imsic_vector * to struct imsic_vector **.

Using smp_call_function_single() to IPI enable (and disable if you don't
want to use the lazy timer disable mechanism) seems feasible as well!

(Let me know if you don't have the spare cycles, and I can help out.)


Bj=C3=B6rn