linux-kernel - Re: [PATCH v3 26/57] perf: Simplify event

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Message-ID: <1cbdae4a-d6ad-4dd8-aa75-9e226c4416fe@kadam.mountain>
Date:   Mon, 12 Jun 2023 17:46:47 +0300
From:   Dan Carpenter <dan.carpenter@...aro.org>
To:     Peter Zijlstra <peterz@...radead.org>
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Subject: Re: [PATCH v3 26/57] perf: Simplify event_function*()

On Mon, Jun 12, 2023 at 11:07:39AM +0200, Peter Zijlstra wrote:
> @@ -224,17 +243,15 @@ static int event_function(void *info)
>  	int ret = 0;
>  
>  	lockdep_assert_irqs_disabled();
> +	guard(perf_ctx_lock)(cpuctx, task_ctx);
>  
> -	perf_ctx_lock(cpuctx, task_ctx);
>  	/*
>  	 * Since we do the IPI call without holding ctx->lock things can have
>  	 * changed, double check we hit the task we set out to hit.
>  	 */
>  	if (ctx->task) {
> -		if (ctx->task != current) {
> -			ret = -ESRCH;
> -			goto unlock;
> -		}
> +		if (ctx->task != current)
> +			return -ESRCH;
>  
>  		/*
>  		 * We only use event_function_call() on established contexts,
> @@ -254,8 +271,6 @@ static int event_function(void *info)
>  	}
>  
>  	efs->func(event, cpuctx, ctx, efs->data);
> -unlock:
> -	perf_ctx_unlock(cpuctx, task_ctx);
>  
>  	return ret;


We can change this to a return 0; and get rid of the "ret" variable.

regards,
dan carpenter