Re: [PATCH RESEND 2/2] perf/x86/lbr: Move cpuc->lbr_xsave allocation out of sleeping region

[Peter Zijlstra]

On Wed, Apr 21, 2021 at 10:18:25AM +0800, Like Xu wrote:
> -int x86_reserve_hardware(void)
> +int x86_reserve_hardware(struct perf_event *event)
>  {
>  	int err = 0;
>  
> @@ -398,8 +398,10 @@ int x86_reserve_hardware(void)
>  		if (atomic_read(&pmc_refcount) == 0) {
>  			if (!reserve_pmc_hardware())
>  				err = -EBUSY;
> -			else
> +			else {
>  				reserve_ds_buffers();
> +				reserve_lbr_buffers(event);
> +			}
>  		}
>  		if (!err)
>  			atomic_inc(&pmc_refcount);
> @@ -650,7 +652,7 @@ static int __x86_pmu_event_init(struct perf_event *event)
>  	if (!x86_pmu_initialized())
>  		return -ENODEV;
>  
> -	err = x86_reserve_hardware();
> +	err = x86_reserve_hardware(event);
>  	if (err)
>  		return err;
>  

This is still complete garbage..