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From:   Andy Lutomirski <luto@kernel.org>
Date:   Tue, 25 Jun 2019 20:36:59 -0700
Message-ID: <CALCETrXyJ8y7PSqf+RmGKjM4VSLXmNEGi6K=Jzw4jmckRQECTg@mail.gmail.com>
Subject: Re: [PATCH 4/9] x86/mm/tlb: Flush remote and local TLBs concurrently
To:     Nadav Amit <namit@vmware.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        X86 ML <x86@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Sasha Levin <sashal@kernel.org>,
        Juergen Gross <jgross@suse.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        linux-hyperv@vger.kernel.org,
        Linux Virtualization <virtualization@lists.linux-foundation.org>,
        kvm list <kvm@vger.kernel.org>,
        xen-devel <xen-devel@lists.xenproject.org>
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On Wed, Jun 12, 2019 at 11:49 PM Nadav Amit <namit@vmware.com> wrote:
>
> To improve TLB shootdown performance, flush the remote and local TLBs
> concurrently. Introduce flush_tlb_multi() that does so. The current
> flush_tlb_others() interface is kept, since paravirtual interfaces need
> to be adapted first before it can be removed. This is left for future
> work. In such PV environments, TLB flushes are not performed, at this
> time, concurrently.

Would it be straightforward to have a default PV flush_tlb_multi()
that uses flush_tlb_others() under the hood?