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Date:   Sat, 25 Jan 2020 21:29:51 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     "Luck, Tony" <tony.luck@intel.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Arvind Sankar <nivedita@alum.mit.edu>,
        "Christopherson, Sean J" <sean.j.christopherson@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@kernel.org>,
        "Yu, Fenghua" <fenghua.yu@intel.com>,
        Ingo Molnar <mingo@redhat.com>, H Peter Anvin <hpa@zytor.com>,
        "Raj, Ashok" <ashok.raj@intel.com>,
        "Shankar, Ravi V" <ravi.v.shankar@intel.com>,
        linux-kernel <linux-kernel@vger.kernel.org>, x86 <x86@kernel.org>
Subject: Re: [PATCH v15] x86/split_lock: Enable split lock detection by kernel
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On Sat, Jan 25, 2020 at 11:55:13AM -0800, Luck, Tony wrote:
> I don't have a good abbreviation.  It would become the joint 2nd longest
> flag name ... top ten lengths look like this on my test machine. So while
> long, not unprecedented.

Yah, I guess we lost that battle long ago.

> Thomas explained how to fix it so we only call the function if TIF_SLD
> is set in either the previous or next process (but not both). So the
> overhead is just extra XOR/AND in the caller.

Yeah.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette