Le 28/06/2022 à 16:19, Igor Mammedov a écrit :
On Thu, 23 Jun 2022 16:58:28 +0200 Brice Goglin <brice.gog...@inria.fr> wrote:The "Memory Proximity Domain Attributes" structure of the ACPI HMAT has a "Processor Proximity Domain Valid" flag that is currently always set because Qemu -numa requires an initiator=X value when hmat=on. Unsetting this flag allows to create more complex memory topologies by having multiple best initiators for a single memory target. This patch allows -numa without initiator=X when hmat=on by keeping the default value MAX_NODES in numa_state->nodes[i].initiator. All places reading numa_state->nodes[i].initiator already check whether it's different from MAX_NODES before using it. Tested with qemu-system-x86_64 -accel kvm \ -machine pc,hmat=on \ -drive if=pflash,format=raw,file=./OVMF.fd \ -drive media=disk,format=qcow2,file=efi.qcow2 \ -smp 4 \ -m 3G \ -object memory-backend-ram,size=1G,id=ram0 \ -object memory-backend-ram,size=1G,id=ram1 \ -object memory-backend-ram,size=1G,id=ram2 \ -numa node,nodeid=0,memdev=ram0,cpus=0-1 \ -numa node,nodeid=1,memdev=ram1,cpus=2-3 \ -numa node,nodeid=2,memdev=ram2 \ -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-latency,latency=10 \ -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-bandwidth,bandwidth=10485760 \ -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-latency,latency=20 \ -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-bandwidth,bandwidth=5242880 \ -numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-latency,latency=30 \ -numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-bandwidth,bandwidth=1048576 \ -numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-latency,latency=20 \ -numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-bandwidth,bandwidth=5242880 \ -numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-latency,latency=10 \ -numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-bandwidth,bandwidth=10485760 \ -numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-latency,latency=30 \ -numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-bandwidth,bandwidth=1048576 which reports NUMA node2 at same distance from both node0 and node1 as seen in lstopo: Machine (2966MB total) + Package P#0 NUMANode P#2 (979MB) Group0 NUMANode P#0 (980MB) Core P#0 + PU P#0 Core P#1 + PU P#1 Group0 NUMANode P#1 (1007MB) Core P#2 + PU P#2 Core P#3 + PU P#3 Before this patch, we had to add ",initiator=X" to "-numa node,nodeid=2,memdev=ram2". The lstopo output difference between initiator=1 and no initiator is: @@ -1,10 +1,10 @@ Machine (2966MB total) + Package P#0 + NUMANode P#2 (979MB) Group0 NUMANode P#0 (980MB) Core P#0 + PU P#0 Core P#1 + PU P#1 Group0 NUMANode P#1 (1007MB) - NUMANode P#2 (979MB) Core P#2 + PU P#2 Core P#3 + PU P#3 Corresponding changes in the HMAT MPDA structure: @@ -49,10 +49,10 @@ [078h 0120 2] Structure Type : 0000 [Memory Proximity Domain Attributes] [07Ah 0122 2] Reserved : 0000 [07Ch 0124 4] Length : 00000028 -[080h 0128 2] Flags (decoded below) : 0001 - Processor Proximity Domain Valid : 1 +[080h 0128 2] Flags (decoded below) : 0000 + Processor Proximity Domain Valid : 0 [082h 0130 2] Reserved1 : 0000 -[084h 0132 4] Attached Initiator Proximity Domain : 00000001 +[084h 0132 4] Attached Initiator Proximity Domain : 00000080^^^^^^^^ where does this value come from?
This is #define MAX_NODES 128, the default value for initiator field in Qemu. But it's meaningless here because "Processor Proximity Domain Valid" flag above is 0.
Brice
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