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Date:   Mon, 22 Jun 2020 21:49:37 +0300
From:   Cyrill Gorcunov <gorcunov@gmail.com>
To:     kan.liang@linux.intel.com
Cc:     peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
        tglx@linutronix.de, bp@alien8.de, x86@kernel.org,
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        alexander.shishkin@linux.intel.com, jolsa@redhat.com,
        namhyung@kernel.org, dave.hansen@intel.com, yu-cheng.yu@intel.com,
        bigeasy@linutronix.de, hpa@zytor.com,
        alexey.budankov@linux.intel.com, eranian@google.com,
        ak@linux.intel.com, like.xu@linux.intel.com,
        yao.jin@linux.intel.com
Subject: Re: [PATCH 21/21] perf/x86/intel/lbr: Support XSAVES for arch LBR
 read
Message-ID: <20200622184937.GV134822@grain>
References: <1592575449-64278-1-git-send-email-kan.liang@linux.intel.com>
 <1592575449-64278-22-git-send-email-kan.liang@linux.intel.com>
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On Fri, Jun 19, 2020 at 07:04:09AM -0700, kan.liang@linux.intel.com wrote:
...
> +static void intel_pmu_arch_lbr_read_xsave(struct cpu_hw_events *cpuc)
> +{
> +	struct x86_perf_task_context_arch_lbr_xsave *xsave = cpuc->lbr_xsave;
> +	struct arch_lbr_entry *lbr;
> +	int i;
> +
> +	if (!xsave)
> +		goto rollback;

Why not make it simplier?

	if (!xsave) {
		intel_pmu_arch_lbr_read(cpuc);
		return;
	}

The goto and "return" statement before the "rollback" label
looks pretty ugly. I'm sorry I didn't follow the series
in details so if you plan to add more handlers at "rollback"
then sure.