From: Jens Axboe <axboe@kernel.dk>
To: Olivier Langlois <olivier@trillion01.com>,
Pavel Begunkov <asml.silence@gmail.com>,
io-uring@vger.kernel.org
Subject: Re: [PATCH 1/2] io_uring/napi: Introduce io_napi_tracking_ops
Date: Wed, 14 Aug 2024 07:17:57 -0600 [thread overview]
Message-ID: <db299eac-8a5f-4cb1-9b1e-ab6e86fea9b9@kernel.dk> (raw)
In-Reply-To: <f86da1b705e98cac8c72e807ca50d2b4ce3a50a2.camel@trillion01.com>
On 8/14/24 5:44 AM, Olivier Langlois wrote:
> At this point, the only thing remaining point to determine is which
> between calling a function pointer of calling a 2 conditional branches
> code is more efficient. and I am of the opinion that the function
> pointer is better due to my C++ background but this is debatable...
As mentioned earlier, your C++ background for systems programming isn't
super relevant here. Even without mitigations, a perfectly predictable
branch is surely faster than an indirect function call. And with
mitigations, it's not even close.
It's a single handler, just do the branches. I don't think this is worth
fretting over.
--
Jens Axboe
next prev parent reply other threads:[~2024-08-14 13:18 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-08-13 16:44 [PATCH 0/2] abstract napi tracking strategy Olivier Langlois
2024-08-13 17:10 ` [PATCH 1/2] io_uring/napi: Introduce io_napi_tracking_ops Olivier Langlois
2024-08-14 11:44 ` Olivier Langlois
2024-08-14 13:17 ` Jens Axboe [this message]
2024-08-13 17:11 ` [PATCH 2/2] io_uring/napi: add static napi tracking strategy Olivier Langlois
2024-08-13 18:33 ` [PATCH 0/2] abstract " Jens Axboe
2024-08-13 21:25 ` Olivier Langlois
2024-08-13 21:44 ` Jens Axboe
2024-08-15 22:17 ` Olivier Langlois
2024-08-15 22:44 ` Olivier Langlois
2024-08-16 14:26 ` Pavel Begunkov
2024-09-16 18:29 ` Olivier Langlois
2024-08-13 22:36 ` Pavel Begunkov
2024-08-14 13:28 ` Pavel Begunkov
2024-08-13 21:34 ` Olivier Langlois
2024-08-13 21:45 ` Jens Axboe
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