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From:   Nadav Amit <namit@vmware.com>
To:     Andy Lutomirski <luto@kernel.org>
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        LKML <linux-kernel@vger.kernel.org>,
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        Linux Virtualization <virtualization@lists.linux-foundation.org>,
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Subject: Re: [PATCH 4/9] x86/mm/tlb: Flush remote and local TLBs concurrently
Thread-Topic: [PATCH 4/9] x86/mm/tlb: Flush remote and local TLBs concurrently
Thread-Index: AQHVIbQneqvfvnASJUSZoJZyXs9UlaatXWmAgAADTQA=
Date:   Wed, 26 Jun 2019 03:48:49 +0000
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> On Jun 25, 2019, at 8:36 PM, Andy Lutomirski <luto@kernel.org> wrote:
>=20
> 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.
>=20
> Would it be straightforward to have a default PV flush_tlb_multi()
> that uses flush_tlb_others() under the hood?

I prefer not to have a default PV implementation that should anyhow go away=
.

I can create unoptimized untested versions for Xen and Hyper-V, if you want=
.