From: Paolo Bonzini <pbonzini@redhat.com>
To: Alexey Kardashevskiy <aik@ozlabs.ru>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH qemu v3 01/13] memory: Postpone flatview and dispatch tree building till all devices are added
Date: Tue, 19 Sep 2017 16:23:13 +0200 [thread overview]
Message-ID: <89a582f4-e4b8-a8ae-8e8e-2fa83e1fd31d@redhat.com> (raw)
In-Reply-To: <2f185edf-3281-e01f-5859-cc43a5df413e@ozlabs.ru>
On 19/09/2017 16:12, Alexey Kardashevskiy wrote:
>>> What is the exact concern about the "[PATCH qemu v3 01/13] memory: Postpone
>>> flatview and dispatch tree building till all devices are added"? Is it that
>>> you missed that modern AS thing in virtio and thought we can do well even
>>> without it?
>> I am afraid that some of the special sysbus devices (not PCI, those go
>> through the bus master DMA region and it's empty on startup) might write
>> to memory during initialization.
>
> And somehow QEMU guarantees that all RAM MRs are rendered to FlatViews even
> though some might be added via -device (can they btw?)?
I don't know, but as discussed on IRC, I think this is a pretty
different change from the rest of the series---which should have zero
change except for going faster---so I'd prefer to keep it out for now
and see where optimization can get us.
Paolo
next prev parent reply other threads:[~2017-09-19 14:23 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-18 10:16 [Qemu-devel] [PATCH qemu v3 00/13] memory: Reduce memory use Alexey Kardashevskiy
2017-09-18 10:16 ` [Qemu-devel] [PATCH qemu v3 01/13] memory: Postpone flatview and dispatch tree building till all devices are added Alexey Kardashevskiy
2017-09-18 14:54 ` Paolo Bonzini
2017-09-19 2:09 ` Alexey Kardashevskiy
2017-09-19 6:57 ` Alexey Kardashevskiy
2017-09-19 7:40 ` Paolo Bonzini
2017-09-19 7:57 ` Alexey Kardashevskiy
2017-09-19 7:59 ` Paolo Bonzini
2017-09-19 7:42 ` Paolo Bonzini
2017-09-19 10:39 ` Alexey Kardashevskiy
2017-09-19 10:47 ` Paolo Bonzini
2017-09-19 14:12 ` Alexey Kardashevskiy
2017-09-19 14:23 ` Paolo Bonzini [this message]
2017-09-18 10:16 ` [Qemu-devel] [PATCH qemu v3 02/13] exec: Explicitely export target AS from address_space_translate_internal Alexey Kardashevskiy
2017-09-18 14:28 ` Eric Blake
2017-09-19 0:15 ` Alexey Kardashevskiy
2017-09-18 10:16 ` [Qemu-devel] [PATCH qemu v3 03/13] memory: Open code FlatView rendering Alexey Kardashevskiy
2017-09-18 14:28 ` Eric Blake
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 04/13] memory: Move FlatView allocation to a helper Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 05/13] memory: Move AddressSpaceDispatch from AddressSpace to FlatView Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 06/13] memory: Remove AddressSpace pointer from AddressSpaceDispatch Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 07/13] memory: Switch memory from using AddressSpace to FlatView Alexey Kardashevskiy
2017-09-18 14:06 ` Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 08/13] memory: Cleanup after switching " Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 09/13] memory: Rename mem_begin/mem_commit/mem_add helpers Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 10/13] memory: Store physical root MR in FlatView Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 11/13] memory: Share FlatView's and dispatch trees between address spaces Alexey Kardashevskiy
2017-09-18 14:37 ` Paolo Bonzini
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 12/13] memory: Get rid of address_space_init_shareable Alexey Kardashevskiy
2017-09-18 10:17 ` [Qemu-devel] [PATCH qemu v3 13/13] memory: Add flat views to HMP "info mtree" Alexey Kardashevskiy
2017-09-18 10:36 ` [Qemu-devel] [PATCH qemu v3 00/13] memory: Reduce memory use no-reply
2017-09-18 14:59 ` Paolo Bonzini
2017-09-19 0:19 ` Alexey Kardashevskiy
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