Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Thu, 6 Sep 2018 16:47:51 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Reinette Chatre <reinette.chatre@intel.com>
Cc:     tglx@linutronix.de, fenghua.yu@intel.com, tony.luck@intel.com,
        mingo@redhat.com, acme@kernel.org, vikas.shivappa@linux.intel.com,
        gavin.hindman@intel.com, jithu.joseph@intel.com,
        dave.hansen@intel.com, hpa@zytor.com, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH V2 4/6] x86/intel_rdt: Add helper to obtain performance
 counter index
Message-ID: <20180906144751.GH24106@hirez.programming.kicks-ass.net>
References: <cover.1534450299.git.reinette.chatre@intel.com>
 <ec245dd86408b92b5cb1553b7004a6a391d54640.1534450299.git.reinette.chatre@intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <ec245dd86408b92b5cb1553b7004a6a391d54640.1534450299.git.reinette.chatre@intel.com>
User-Agent: Mutt/1.10.0 (2018-05-17)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Thu, Aug 16, 2018 at 01:16:07PM -0700, Reinette Chatre wrote:

> +static inline int x86_perf_rdpmc_ctr_get(struct perf_event *event)
> +{
> +	lockdep_assert_irqs_disabled();
> +
> +	return IS_ERR_OR_NULL(event) ? -1 : event->hw.event_base_rdpmc;
> +}

That should be in arch/x86/include/asm/perf_event.h if anywhere. Also,
call the thing x86_perf_rdpmc_index(), that's consistent with the other
naming.

I don't think there's any point in testing for !event, this is an
interface that mandates you know wth you're doing anyway.