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From: Pavel Fedin <p.fedin@samsung.com>
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Date: Wed, 14 Oct 2015 14:49:14 +0300
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Subject: Re: [Qemu-devel] [PATCH v2 0/3] Make KVM/MSI code device-ID-aware
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To: "'Michael S. Tsirkin'" <mst@redhat.com>
Cc: 'Peter Maydell' <peter.maydell@linaro.org>, qemu-devel@nongnu.org, 'Paolo Bonzini' <pbonzini@redhat.com>

 Hello!

> OK, so we could rename stream id to requester id. That at least would
> make sense at the pci level, and would make it unique per hierarchy.

 Yes, we can, i'm fine with the rename. Additionally, "requester ID" is the official term used in GICv3 architecture manual. When i
implemented it i didn't have arch manual, therefore had to invent the name.

> But I suspect all these optimizations break later when we need to support
> multiple root complex devices.

 Not necessarily. IIRC we have three bits used for other purposes in MemTxAttrs. So, we could extend our RID up to 24 bits and still
be fine. Even if we use 32 bits, our MemTxAttrs would still fit into register on 64-bit platforms, and into two registers on 32-bit
platforms. The same as MSIMessage (don't remember exact name).

 Should i post v3, including the rename, or will you just rename stream_id to requester_id yourself?

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia