linux-kernel - Re: [PATCH 5/5] x86/mbm: Add support for MBM counter overflow handling

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Message-ID: <alpine.DEB.2.11.1602241131300.3670@nanos>
Date:	Wed, 24 Feb 2016 11:36:16 +0100 (CET)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	Vikas Shivappa <vikas.shivappa@...ux.intel.com>
cc:	vikas.shivappa@...el.com, x86@...nel.org,
	linux-kernel@...r.kernel.org, hpa@...or.com, mingo@...nel.org,
	peterz@...radead.org, ravi.v.shankar@...el.com,
	tony.luck@...el.com, fenghua.yu@...el.com,
	kanaka.d.juvva@...el.com, h.peter.anvin@...el.com
Subject: Re: [PATCH 5/5] x86/mbm: Add support for MBM counter overflow
 handling

On Wed, 10 Feb 2016, Vikas Shivappa wrote:
> +static enum hrtimer_restart mbm_hrtimer_handle(struct hrtimer *hrtimer)
> +{
> +	if (list_empty(&cache_groups))
> +		goto out;
> +
> +	list_for_each_entry(iter, &cache_groups, hw.cqm_groups_entry) {

....

> +		}
> +	}
> +
> +out:
> +	raw_spin_unlock_irqrestore(&cache_lock, flags);
> +	mutex_unlock(&cache_mutex);
> +
> +	hrtimer_forward_now(hrtimer, ms_to_ktime(MBM_CTR_OVERFLOW_TIME));
> +
> +	return HRTIMER_RESTART;

Why is that timer restarted if cache_groups is empty?

Thanks,

	tglx