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KVM: PPC: Book3S HV: Move HPT guest TLB flushing to C code

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This replaces assembler code in book3s_hv_rmhandlers.S that checks
the kvm->arch.need_tlb_flush cpumask and optionally does a TLB flush
with C code in book3s_hv_builtin.c.  Note that unlike the radix
version, the hash version doesn't do an explicit ERAT invalidation
because we will invalidate and load up the SLB before entering the
guest, and that will invalidate the ERAT.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Paul Mackerras 2019-04-29 19:00:40 +10:00
parent 7ae9bda7ed
commit 2940ba0c48
3 changed files with 35 additions and 34 deletions
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2
arch/powerpc/include/asm/kvm_ppc.h
View File

@ -476,6 +476,8 @@ extern void kvm_hv_vm_activated(void);
extern void kvm_hv_vm_deactivated(void);
extern bool kvm_hv_mode_active(void);
extern void kvmppc_hpt_check_need_tlb_flush(struct kvm *kvm);
#else
static inline void __init kvm_cma_reserve(void)
{}

29
arch/powerpc/kvm/book3s_hv_builtin.c
View File

@ -805,3 +805,32 @@ void kvmppc_guest_entry_inject_int(struct kvm_vcpu *vcpu)
vcpu->arch.doorbell_request = 0;
}
}
void kvmppc_hpt_check_need_tlb_flush(struct kvm *kvm)
{
int pcpu = raw_smp_processor_id();
unsigned long rb, set;
/*
* On POWER9, individual threads can come in here, but the
* TLB is shared between the 4 threads in a core, hence
* invalidating on one thread invalidates for all.
* Thus we make all 4 threads use the same bit.
*/
if (cpu_has_feature(CPU_FTR_ARCH_300))
pcpu = cpu_first_thread_sibling(pcpu);
if (cpumask_test_cpu(pcpu, &kvm->arch.need_tlb_flush)) {
rb = PPC_BIT(52); /* IS = 2 */
for (set = 0; set < kvm->arch.tlb_sets; ++set) {
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r" (rb), "i" (0), "i" (0), "i" (0),
"r" (0) : "memory");
rb += PPC_BIT(51); /* increment set number */
}
asm volatile("ptesync": : :"memory");
/* Clear the bit after the TLB flush */
cpumask_clear_cpu(pcpu, &kvm->arch.need_tlb_flush);
}
}

38
arch/powerpc/kvm/book3s_hv_rmhandlers.S
View File

@ -623,40 +623,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
isync
/* See if we need to flush the TLB. Hash has to be done in RM */
lhz r6,PACAPACAINDEX(r13) /* test_bit(cpu, need_tlb_flush) */
BEGIN_FTR_SECTION
/*
* On POWER9, individual threads can come in here, but the
* TLB is shared between the 4 threads in a core, hence
* invalidating on one thread invalidates for all.
* Thus we make all 4 threads use the same bit here.
*/
clrrdi r6,r6,2
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
clrldi r7,r6,64-6 /* extract bit number (6 bits) */
srdi r6,r6,6 /* doubleword number */
sldi r6,r6,3 /* address offset */
add r6,r6,r9
addi r6,r6,KVM_NEED_FLUSH /* dword in kvm->arch.need_tlb_flush */
li r8,1
sld r8,r8,r7
ld r7,0(r6)
and. r7,r7,r8
beq 22f
/* Flush the TLB of any entries for this LPID */
lwz r0,KVM_TLB_SETS(r9)
mtctr r0
li r7,0x800 /* IS field = 0b10 */
ptesync
li r0,0 /* RS for P9 version of tlbiel */
28: tlbiel r7 /* On P9, rs=0, RIC=0, PRS=0, R=0 */
addi r7,r7,0x1000
bdnz 28b
ptesync
23: ldarx r7,0,r6 /* clear the bit after TLB flushed */
andc r7,r7,r8
stdcx. r7,0,r6
bne 23b
mr r3, r9 /* kvm pointer */
bl kvmppc_hpt_check_need_tlb_flush
nop
ld r5, HSTATE_KVM_VCORE(r13)
/* Add timebase offset onto timebase */
22: ld r8,VCORE_TB_OFFSET(r5)