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| author | Nicholas Piggin <npiggin@gmail.com> | 2018-05-17 09:59:10 +0300 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2018-05-18 08:38:23 +0300 |
| commit | b7557451475d747740bc1598045bd273ece80ab0 (patch) | |
| tree | 95e5efbb1667f88712274c0b3152dff2699b2b77 /arch/powerpc/include/asm/kvm_host.h | |
| parent | f19d1f367a506bc645f8d6695942b8873fc82c84 (diff) | |
| download | linux-b7557451475d747740bc1598045bd273ece80ab0.tar.xz | |
KVM: PPC: Book3S HV: Lockless tlbie for HPT hcalls
tlbies to an LPAR do not have to be serialised since POWER4/PPC970,
after which the MMU_FTR_LOCKLESS_TLBIE feature was introduced to
avoid tlbie locking.
Since commit c17b98cf6028 ("KVM: PPC: Book3S HV: Remove code for
PPC970 processors"), KVM no longer supports processors that do not
have this feature, so the tlbie locking can be removed completely.
A sanity check for the feature is put in kvmppc_mmu_hv_init.
Testing was done on a POWER9 system in HPT mode, with a -smp 32 guest
in HPT mode. 32 instances of the powerpc fork benchmark from selftests
were run with --fork, and the results measured.
Without this patch, total throughput was about 13.5K/sec, and this is
the top of the host profile:
74.52% [k] do_tlbies
2.95% [k] kvmppc_book3s_hv_page_fault
1.80% [k] calc_checksum
1.80% [k] kvmppc_vcpu_run_hv
1.49% [k] kvmppc_run_core
After this patch, throughput was about 51K/sec, with this profile:
21.28% [k] do_tlbies
5.26% [k] kvmppc_run_core
4.88% [k] kvmppc_book3s_hv_page_fault
3.30% [k] _raw_spin_lock_irqsave
3.25% [k] gup_pgd_range
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'arch/powerpc/include/asm/kvm_host.h')
| -rw-r--r-- | arch/powerpc/include/asm/kvm_host.h | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8b0ee5e09ea3..89f44ecc4dbd 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -269,7 +269,6 @@ struct kvm_arch { unsigned long host_lpcr; unsigned long sdr1; unsigned long host_sdr1; - int tlbie_lock; unsigned long lpcr; unsigned long vrma_slb_v; int mmu_ready; |