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Date:   Thu, 29 Jun 2023 10:37:36 -0700
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Subject: Re: [PATCH v2 1/1] Add a new sysctl to disable io_uring system-wide
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To:     Matteo Rizzo <matteorizzo@google.com>
Cc:     linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        io-uring@vger.kernel.org, jordyzomer@google.com, evn@google.com,
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        dave.hansen@linux.intel.com, ribalda@chromium.org,
        chenhuacai@kernel.org, steve@sk2.org, gpiccoli@igalia.com,
        ldufour@linux.ibm.com, bhe@redhat.com, oleksandr@natalenko.name
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From:   Bart Van Assche <bvanassche@acm.org>
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On 6/29/23 08:28, Matteo Rizzo wrote:
> On Thu, 29 Jun 2023 at 17:16, Bart Van Assche <bvanassche@acm.org> wrote:
>>
>> On 6/29/23 06:27, Matteo Rizzo wrote:
>>> +static int __read_mostly sysctl_io_uring_disabled;
>>
>> Shouldn't this be a static key instead of an int in order to minimize the
>> performance impact on the io_uring_setup() system call? See also
>> Documentation/staging/static-keys.rst.
>>
> Is io_uring_setup in any hot path? io_uring_create is marked as __cold.

I confused io_uring_setup() with io_uring_enter() so please ignore my comment.

Bart.