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| author | Paul Mackerras <paulus@ozlabs.org> | 2018-10-08 08:30:48 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-10-09 08:04:27 +0300 |
| commit | d24ea8a7336a2c392728e2cf909d607a680feb7b (patch) | |
| tree | 1bc989b981481e26fb0197e8c8f013eeff490b21 /arch/powerpc/kvm/book3s_hv_rmhandlers.S | |
| parent | e7b17d50471a8bfddf7c976c7d3a68104272b2f3 (diff) | |
| download | linux-d24ea8a7336a2c392728e2cf909d607a680feb7b.tar.xz | |
KVM: PPC: Book3S: Simplify external interrupt handling
Currently we use two bits in the vcpu pending_exceptions bitmap to
indicate that an external interrupt is pending for the guest, one
for "one-shot" interrupts that are cleared when delivered, and one
for interrupts that persist until cleared by an explicit action of
the OS (e.g. an acknowledge to an interrupt controller). The
BOOK3S_IRQPRIO_EXTERNAL bit is used for one-shot interrupt requests
and BOOK3S_IRQPRIO_EXTERNAL_LEVEL is used for persisting interrupts.
In practice BOOK3S_IRQPRIO_EXTERNAL never gets used, because our
Book3S platforms generally, and pseries in particular, expect
external interrupt requests to persist until they are acknowledged
at the interrupt controller. That combined with the confusion
introduced by having two bits for what is essentially the same thing
makes it attractive to simplify things by only using one bit. This
patch does that.
With this patch there is only BOOK3S_IRQPRIO_EXTERNAL, and by default
it has the semantics of a persisting interrupt. In order to avoid
breaking the ABI, we introduce a new "external_oneshot" flag which
preserves the behaviour of the KVM_INTERRUPT ioctl with the
KVM_INTERRUPT_SET argument.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_rmhandlers.S')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 1d14046124a0..77960e68f7b0 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1122,11 +1122,11 @@ kvmppc_cede_reentry: /* r4 = vcpu, r13 = paca */ /* Check if we can deliver an external or decrementer interrupt now */ ld r0, VCPU_PENDING_EXC(r4) - rldicl r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL_LEVEL, 63 + rldicl r0, r0, 64 - BOOK3S_IRQPRIO_EXTERNAL, 63 cmpdi cr1, r0, 0 andi. r8, r11, MSR_EE mfspr r8, SPRN_LPCR - /* Insert EXTERNAL_LEVEL bit into LPCR at the MER bit position */ + /* Insert EXTERNAL bit into LPCR at the MER bit position */ rldimi r8, r0, LPCR_MER_SH, 63 - LPCR_MER_SH mtspr SPRN_LPCR, r8 isync |