KVM: PPC: Book3S HV: Make radix handle process scoped LPID flush in C, with relocation on

The radix guest code can has fewer restrictions about what context it
can run in, so move this flushing out of assembly and have it use the
Linux TLB flush implementations introduced previously.

This allows powerpc:tlbie trace events to be used.

This changes the tlbiel sequence to only execute RIC=2 flush once on
the first set flushed, then RIC=0 for the rest of the sets. The end
result of the flush should be unchanged. This matches the local PID
flush pattern that was introduced in a5998fcb92 ("powerpc/mm/radix:
Optimise tlbiel flush all case").

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 336e3468e70002191ef8ec729ba15f1e0441c58e..9b6a118ea77169056f8b4ce34b428a0deb044bc5 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2958,6 +2958,32 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc)
        for (sub = 0; sub < core_info.n_subcores; ++sub)
                spin_unlock(&core_info.vc[sub]->lock);
 
+       if (kvm_is_radix(vc->kvm)) {
+               int tmp = pcpu;
+
+               /*
+                * Do we need to flush the process scoped TLB for the LPAR?
+                *
+                * 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.
+                *
+                * Hash must be flushed in realmode in order to use tlbiel.
+                */
+               mtspr(SPRN_LPID, vc->kvm->arch.lpid);
+               isync();
+
+               if (cpu_has_feature(CPU_FTR_ARCH_300))
+                       tmp &= ~0x3UL;
+
+               if (cpumask_test_cpu(tmp, &vc->kvm->arch.need_tlb_flush)) {
+                       radix__local_flush_tlb_lpid_guest(vc->kvm->arch.lpid);
+                       /* Clear the bit after the TLB flush */
+                       cpumask_clear_cpu(tmp, &vc->kvm->arch.need_tlb_flush);
+               }
+       }
+
        /*
         * Interrupts will be enabled once we get into the guest,
         * so tell lockdep that we're about to enable interrupts.

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index 07ca1b2a7966b5f58188b8b0b685eb581cc2b695..ef9e665fc8e285d0d927fe084b1777d9aadbc3ec 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -636,6 +636,10 @@ kvmppc_hv_entry:
        /* Primary thread switches to guest partition. */
        cmpwi   r6,0
        bne     10f
+
+       /* Radix has already switched LPID and flushed core TLB */
+       bne     cr7, 22f
+
        lwz     r7,KVM_LPID(r9)
 BEGIN_FTR_SECTION
        ld      r6,KVM_SDR1(r9)
@@ -647,7 +651,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
        mtspr   SPRN_LPID,r7
        isync
 
-       /* See if we need to flush the TLB */
+       /* 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
        /*
@@ -674,15 +678,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
        li      r7,0x800                /* IS field = 0b10 */
        ptesync
        li      r0,0                    /* RS for P9 version of tlbiel */
-       bne     cr7, 29f
 28:    tlbiel  r7                      /* On P9, rs=0, RIC=0, PRS=0, R=0 */
        addi    r7,r7,0x1000
        bdnz    28b
-       b       30f
-29:    PPC_TLBIEL(7,0,2,1,1)           /* for radix, RIC=2, PRS=1, R=1 */
-       addi    r7,r7,0x1000
-       bdnz    29b
-30:    ptesync
+       ptesync
 23:    ldarx   r7,0,r6                 /* clear the bit after TLB flushed */
        andc    r7,r7,r8
        stdcx.  r7,0,r6