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0b0b831016
This patch implements hypercalls allowing a PAPR guest to resize its own hash page table. This will eventually allow for more flexible memory hotplug. The implementation is partially asynchronous, handled in a special thread running the hpt_prepare_thread() function. The state of a pending resize is stored in SPAPR_MACHINE->pending_hpt. The H_RESIZE_HPT_PREPARE hypercall will kick off creation of a new HPT, or, if one is already in progress, monitor it for completion. If there is an existing HPT resize in progress that doesn't match the size specified in the call, it will cancel it, replacing it with a new one matching the given size. The H_RESIZE_HPT_COMMIT completes transition to a resized HPT, and can only be called successfully once H_RESIZE_HPT_PREPARE has successfully completed initialization of a new HPT. The guest must ensure that there are no concurrent accesses to the existing HPT while this is called (this effectively means stop_machine() for Linux guests). For now H_RESIZE_HPT_COMMIT goes through the whole old HPT, rehashing each HPTE into the new HPT. This can have quite high latency, but it seems to be of the order of typical migration downtime latencies for HPTs of size up to ~2GiB (which would be used in a 256GiB guest). In future we probably want to move more of the rehashing to the "prepare" phase, by having H_ENTER and other hcalls update both current and pending HPTs. That's a project for another day, but should be possible without any changes to the guest interface. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> |
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| .. | ||
| translate | ||
| arch_dump.c | ||
| compat.c | ||
| cpu-models.c | ||
| cpu-models.h | ||
| cpu-qom.h | ||
| cpu.c | ||
| cpu.h | ||
| dfp_helper.c | ||
| excp_helper.c | ||
| fpu_helper.c | ||
| gdbstub.c | ||
| helper.h | ||
| helper_regs.h | ||
| int_helper.c | ||
| internal.h | ||
| kvm-stub.c | ||
| kvm.c | ||
| kvm_ppc.h | ||
| machine.c | ||
| Makefile.objs | ||
| mem_helper.c | ||
| mfrom_table.c | ||
| mfrom_table_gen.c | ||
| misc_helper.c | ||
| mmu-book3s-v3.c | ||
| mmu-book3s-v3.h | ||
| mmu-hash32.c | ||
| mmu-hash32.h | ||
| mmu-hash64.c | ||
| mmu-hash64.h | ||
| mmu-radix64.c | ||
| mmu-radix64.h | ||
| mmu_helper.c | ||
| monitor.c | ||
| STATUS | ||
| timebase_helper.c | ||
| trace-events | ||
| translate.c | ||
| translate_init.c | ||
| user_only_helper.c | ||