From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Subject: Re: [PATCH 06/19] kernel: convert perf_event_context.refcount from
 atomic_t to refcount_t
Date: Mon, 20 Feb 2017 11:28:25 +0100
Message-ID: <20170220102825.GL6500@twins.programming.kicks-ass.net>
References: <1487585948-6401-1-git-send-email-elena.reshetova@intel.com>
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To: Elena Reshetova <elena.reshetova-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
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List-Id: linux-audit@redhat.com

On Mon, Feb 20, 2017 at 12:18:55PM +0200, Elena Reshetova wrote:
> +++ b/kernel/events/core.c
> @@ -1108,7 +1108,7 @@ static void perf_event_ctx_deactivate(struct perf_event_context *ctx)
>  
>  static void get_ctx(struct perf_event_context *ctx)
>  {
> -	WARN_ON(!atomic_inc_not_zero(&ctx->refcount));
> +	WARN_ON(!refcount_inc_not_zero(&ctx->refcount));
>  }

You can change that to refcount_inc(), as that has the exact same
semantics.