Subject: Re: [PATCH v7 8/8] x86/tlb: just do tlb flush on one of siblings
 of SMT
From: Peter Zijlstra <peterz@infradead.org>
To: Jan Beulich <JBeulich@suse.com>
Cc: Alex Shi <alex.shi@intel.com>, borislav.petkov@amd.com, arnd@arndb.de,
        akinobu.mita@gmail.com, eric.dumazet@gmail.com, fweisbec@gmail.com,
        rostedt@goodmis.org, hughd@google.com, jeremy@goop.org,
        len.brown@intel.com, tony.luck@intel.com, yongjie.ren@intel.com,
        kamezawa.hiroyu@jp.fujitsu.com, seto.hidetoshi@jp.fujitsu.com,
        penberg@kernel.org, yinghai@kernel.org, tglx@linutronix.de,
        akpm@linux-foundation.org, ak@linux.intel.com, luto@mit.edu,
        avi@redhat.com, dhowells@redhat.com, mingo@redhat.com, riel@redhat.com,
        cpw@sgi.com, steiner@sgi.com, linux-kernel@vger.kernel.org,
        viro@zeniv.linux.org.uk, hpa@zytor.com
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Date: Wed, 23 May 2012 19:15:38 +0200
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On Wed, 2012-05-23 at 19:09 +0200, Peter Zijlstra wrote:
> > There is no comment or anything else indicating that this is
> > suitable for dual-thread CPUs only - when there are more than
> > 2 threads per core, the intended effect won't be achieved.
> 
> Why would that be? Won't higher thread count still share the same
> resources just more so? 

Ah, I see, you're saying his code is buggy for >2 threads. Agreed.

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