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Date:   Tue, 5 Apr 2022 16:07:19 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Wyes Karny <wyes.karny@amd.com>
Cc:     linux-kernel@vger.kernel.org, Lewis.Carroll@amd.com,
        Mario.Limonciello@amd.com, gautham.shenoy@amd.com,
        Ananth.Narayan@amd.com, bharata@amd.com, len.brown@intel.com,
        x86@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        dave.hansen@linux.intel.com, hpa@zytor.com,
        chang.seok.bae@intel.com, keescook@chromium.org, metze@samba.org,
        zhengqi.arch@bytedance.com, mark.rutland@arm.com
Subject: Re: [PATCH] x86: Prefer MWAIT over HALT on AMD processors
Message-ID: <YkxNFyXqC12nXyfM@hirez.programming.kicks-ass.net>
References: <20220405130021.557880-1-wyes.karny@amd.com>
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On Tue, Apr 05, 2022 at 06:30:21PM +0530, Wyes Karny wrote:
> +static inline bool early_mwait_supported(const struct cpuinfo_x86 *c)
> +{
> +	if (c->x86_vendor == X86_VENDOR_INTEL)
> +		return true;
> +
> +	if (c->x86_vendor == X86_VENDOR_AMD && cpu_has(c, X86_FEATURE_ZEN))

What about Hygon? For some reason you guys don't co-ordinate and we end
up getting endless 'make-same' patches, sometimes separated by years :/

> +		return true;
> +
> +	return false;
> +}