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Date:   Fri, 6 May 2022 16:53:36 +0530
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Subject: Re: [PATCH v2 1/3] x86: Use HALT in default_idle when idle=nomwait
 cmdline arg is passed
Content-Language: en-US
To:     Dave Hansen <dave.hansen@intel.com>, linux-kernel@vger.kernel.org
Cc:     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, peterz@infradead.org, chang.seok.bae@intel.com,
        keescook@chromium.org, metze@samba.org, zhengqi.arch@bytedance.com,
        mark.rutland@arm.com, puwen@hygon.cn, rafael.j.wysocki@intel.com,
        andrew.cooper3@citrix.com, jing2.liu@intel.com,
        jmattson@google.com, pawan.kumar.gupta@linux.intel.com
References: <20220505104856.452311-1-wyes.karny@amd.com>
 <20220505104856.452311-2-wyes.karny@amd.com>
 <12ce24d3-9b46-5c2e-c5c7-c690cb3ca81a@intel.com>
From:   Wyes Karny <wyes.karny@amd.com>
In-Reply-To: <12ce24d3-9b46-5c2e-c5c7-c690cb3ca81a@intel.com>
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On 5/5/2022 10:43 PM, Dave Hansen wrote:
> On 5/5/22 03:48, Wyes Karny wrote:
>> When kernel is booted with idle=nomwait avoid selecting MWAIT
>> as the  default idle state.
>>
>> If the user boots the kernel with idle=nomwait, it is a clear
>> indication that they do not prefer the use of mwait as the default
>> idle state.  However, the current code does not take this into
>> consideration while selecting the default idle state on x86.
>>
>> This patch fixes it by checking for the idle=nomwait boot option in
>> prefer_mwait_c1_over_halt().
> 
> There are a couple of places in the existing documentation that talk
> about idle=nomwait.  Could you please fix those up to make it clear that
> the option is no longer specific to intel_idle?  We don't need a rewrite
> or anything, just some small tweaks in the language.

Sure, will do. Thanks!