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Date: Wed, 7 Aug 2024 13:15:20 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: James Clark <james.clark@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org, Al Grant <al.grant@arm.com>,
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Subject: Re: [PATCH] drivers/perf: arm_spe: Use perf_allow_kernel() for
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In-Reply-To: <20240807105441.2156738-1-james.clark@linaro.org>

On Wed, Aug 07, 2024 at 11:54:41AM +0100, James Clark wrote:
> diff --git a/kernel/events/core.c b/kernel/events/core.c
> index aa3450bdc227..4a69583e329a 100644
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -417,6 +417,7 @@ static struct kmem_cache *perf_event_cache;
>   *   2 - disallow kernel profiling for unpriv
>   */
>  int sysctl_perf_event_paranoid __read_mostly = 2;
> +EXPORT_SYMBOL_GPL(sysctl_perf_event_paranoid);

I'm never a fan of exporting variables. Perhaps create a helper function
that returns the value and use that where required?

That avoids modules getting the idea it would be okay to change this
valie themselves.