| Message ID | 20200605213853.14959-1-sean.j.christopherson@intel.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | KVM: Cleanup and unify kvm_mmu_memory_cache usage | expand |
Hi Sean, On 2020-06-05 22:38, Sean Christopherson wrote: > This series resurrects Christoffer Dall's series[1] to provide a common > MMU memory cache implementation that can be shared by x86, arm64 and > MIPS. > > It also picks up a suggested change from Ben Gardon[2] to clear shadow > page tables during initial allocation so as to avoid clearing entire > pages while holding mmu_lock. > > The front half of the patches do house cleaning on x86's memory cache > implementation in preparation for moving it to common code, along with > a > fair bit of cleanup on the usage. The middle chunk moves the patches > to > common KVM, and the last two chunks convert arm64 and MIPS to the > common > implementation. > > Cleanup aside, the notable difference from Christoffer and Ben's > proposed > patches is to make __GFP_ZERO optional, e.g. to allow x86 to skip > zeroing > for its gfns array and to provide line of sight for my > cannot-yet-be-discussed-in-detail use case for non-zero initialized > shadow > page tables[3]. > > Tested on x86 only, no testing whatsoever on arm64 or MIPS. I've given it a go on a small bunch of arm64 boxes, and nothing caught fire! As Ben noticed, the series isn't bisectable (easily fixed) and there is some nagging conflicts with the current state of mainline. Overall, a very welcome cleanup. The only point of contention is the change in allocation accounting on arm64, but there is an easy fix for that. Thanks, M.
This series resurrects Christoffer Dall's series[1] to provide a common MMU memory cache implementation that can be shared by x86, arm64 and MIPS. It also picks up a suggested change from Ben Gardon[2] to clear shadow page tables during initial allocation so as to avoid clearing entire pages while holding mmu_lock. The front half of the patches do house cleaning on x86's memory cache implementation in preparation for moving it to common code, along with a fair bit of cleanup on the usage. The middle chunk moves the patches to common KVM, and the last two chunks convert arm64 and MIPS to the common implementation. Cleanup aside, the notable difference from Christoffer and Ben's proposed patches is to make __GFP_ZERO optional, e.g. to allow x86 to skip zeroing for its gfns array and to provide line of sight for my cannot-yet-be-discussed-in-detail use case for non-zero initialized shadow page tables[3]. Tested on x86 only, no testing whatsoever on arm64 or MIPS. [1] https://lkml.kernel.org/r/20191105110357.8607-1-christoffer.dall@arm.com [2] https://lkml.kernel.org/r/20190926231824.149014-4-bgardon@google.com [3] https://lkml.kernel.org/r/20191127180731.GC16845@linux.intel.com Sean Christopherson (21): KVM: x86/mmu: Track the associated kmem_cache in the MMU caches KVM: x86/mmu: Consolidate "page" variant of memory cache helpers KVM: x86/mmu: Use consistent "mc" name for kvm_mmu_memory_cache locals KVM: x86/mmu: Remove superfluous gotos from mmu_topup_memory_caches() KVM: x86/mmu: Try to avoid crashing KVM if a MMU memory cache is empty KVM: x86/mmu: Move fast_page_fault() call above mmu_topup_memory_caches() KVM: x86/mmu: Topup memory caches after walking GVA->GPA KVM: x86/mmu: Clean up the gorilla math in mmu_topup_memory_caches() KVM: x86/mmu: Separate the memory caches for shadow pages and gfn arrays KVM: x86/mmu: Make __GFP_ZERO a property of the memory cache KVM: x86/mmu: Zero allocate shadow pages (outside of mmu_lock) KVM: x86/mmu: Skip filling the gfn cache for guaranteed direct MMU topups KVM: x86/mmu: Prepend "kvm_" to memory cache helpers that will be global KVM: Move x86's version of struct kvm_mmu_memory_cache to common code KVM: Move x86's MMU memory cache helpers to common KVM code KVM: arm64: Drop @max param from mmu_topup_memory_cache() KVM: arm64: Use common code's approach for __GFP_ZERO with memory caches KVM: arm64: Use common KVM implementation of MMU memory caches KVM: MIPS: Drop @max param from mmu_topup_memory_cache() KVM: MIPS: Account pages used for GPA page tables KVM: MIPS: Use common KVM implementation of MMU memory caches arch/arm64/include/asm/kvm_host.h | 11 --- arch/arm64/include/asm/kvm_types.h | 8 ++ arch/arm64/kvm/arm.c | 2 + arch/arm64/kvm/mmu.c | 54 +++-------- arch/mips/include/asm/kvm_host.h | 11 --- arch/mips/include/asm/kvm_types.h | 7 ++ arch/mips/kvm/mmu.c | 44 ++------- arch/powerpc/include/asm/kvm_types.h | 5 ++ arch/s390/include/asm/kvm_types.h | 5 ++ arch/x86/include/asm/kvm_host.h | 14 +-- arch/x86/include/asm/kvm_types.h | 7 ++ arch/x86/kvm/mmu/mmu.c | 129 +++++++++------------------ arch/x86/kvm/mmu/paging_tmpl.h | 10 +-- include/linux/kvm_host.h | 7 ++ include/linux/kvm_types.h | 19 ++++ virt/kvm/kvm_main.c | 55 ++++++++++++ 16 files changed, 178 insertions(+), 210 deletions(-) create mode 100644 arch/arm64/include/asm/kvm_types.h create mode 100644 arch/mips/include/asm/kvm_types.h create mode 100644 arch/powerpc/include/asm/kvm_types.h create mode 100644 arch/s390/include/asm/kvm_types.h create mode 100644 arch/x86/include/asm/kvm_types.h