| Message ID | 20240307183907.1184775-3-coltonlewis@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add arch_timer_edge_cases selftest | expand |
nitpick: Shortlog should read KVM: selftests: Ensure pending interrupts are handled in arch_timer test The fact that we're dealing with pending interrupts is critical here; the ISB has no interaction with the GIC in terms of interrupt timing as it gets to the PE. On Thu, Mar 07, 2024 at 06:39:06PM +0000, Colton Lewis wrote: > Break up the asm instructions poking daifclr and daifset to handle > interrupts. R_RBZYL specifies pending interrupts will be handle after > context synchronization events such as an ISB. > > Introduce a function wrapper for the WFI instruction. > > Signed-off-by: Colton Lewis <coltonlewis@google.com> > --- > tools/testing/selftests/kvm/aarch64/vgic_irq.c | 12 ++++++------ > tools/testing/selftests/kvm/include/aarch64/gic.h | 3 +++ > tools/testing/selftests/kvm/lib/aarch64/gic.c | 5 +++++ > 3 files changed, 14 insertions(+), 6 deletions(-) > > diff --git a/tools/testing/selftests/kvm/aarch64/vgic_irq.c b/tools/testing/selftests/kvm/aarch64/vgic_irq.c > index d3bf584d2cc1..85f182704d79 100644 > --- a/tools/testing/selftests/kvm/aarch64/vgic_irq.c > +++ b/tools/testing/selftests/kvm/aarch64/vgic_irq.c > @@ -269,13 +269,13 @@ static void guest_inject(struct test_args *args, > KVM_INJECT_MULTI(cmd, first_intid, num); > > while (irq_handled < num) { > - asm volatile("wfi\n" > - "msr daifclr, #2\n" > - /* handle IRQ */ > - "msr daifset, #2\n" > - : : : "memory"); > + gic_wfi(); > + local_irq_enable(); > + isb(); > + /* handle IRQ */ > + local_irq_disable(); Sorry, this *still* annoys me. Please move the comment above the ISB, you're documenting a behavior that is implied by the instruction, not anything else. > } > - asm volatile("msr daifclr, #2" : : : "memory"); > + local_irq_enable(); > > GUEST_ASSERT_EQ(irq_handled, num); > for (i = first_intid; i < num + first_intid; i++) > diff --git a/tools/testing/selftests/kvm/include/aarch64/gic.h b/tools/testing/selftests/kvm/include/aarch64/gic.h > index 9043eaef1076..f474714e4cb2 100644 > --- a/tools/testing/selftests/kvm/include/aarch64/gic.h > +++ b/tools/testing/selftests/kvm/include/aarch64/gic.h > @@ -47,4 +47,7 @@ void gic_irq_clear_pending(unsigned int intid); > bool gic_irq_get_pending(unsigned int intid); > void gic_irq_set_config(unsigned int intid, bool is_edge); > > +/* Execute a Wait For Interrupt instruction. */ > +void gic_wfi(void); > + > #endif /* SELFTEST_KVM_GIC_H */ > diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic.c b/tools/testing/selftests/kvm/lib/aarch64/gic.c > index 9d15598d4e34..392e3f581ae0 100644 > --- a/tools/testing/selftests/kvm/lib/aarch64/gic.c > +++ b/tools/testing/selftests/kvm/lib/aarch64/gic.c > @@ -164,3 +164,8 @@ void gic_irq_set_config(unsigned int intid, bool is_edge) > GUEST_ASSERT(gic_common_ops); > gic_common_ops->gic_irq_set_config(intid, is_edge); > } > + > +void gic_wfi(void) > +{ > + asm volatile("wfi"); > +} Ok, I left a comment about this last time... WFI instructions are only relevant in the context of a PE, so it would be natural to add such a helper to aarch64/processor.h. There are definitely implementations out there that do not use a GIC and still have WFI instructions.
diff --git a/tools/testing/selftests/kvm/aarch64/vgic_irq.c b/tools/testing/selftests/kvm/aarch64/vgic_irq.c index d3bf584d2cc1..85f182704d79 100644 --- a/tools/testing/selftests/kvm/aarch64/vgic_irq.c +++ b/tools/testing/selftests/kvm/aarch64/vgic_irq.c @@ -269,13 +269,13 @@ static void guest_inject(struct test_args *args, KVM_INJECT_MULTI(cmd, first_intid, num); while (irq_handled < num) { - asm volatile("wfi\n" - "msr daifclr, #2\n" - /* handle IRQ */ - "msr daifset, #2\n" - : : : "memory"); + gic_wfi(); + local_irq_enable(); + isb(); + /* handle IRQ */ + local_irq_disable(); } - asm volatile("msr daifclr, #2" : : : "memory"); + local_irq_enable(); GUEST_ASSERT_EQ(irq_handled, num); for (i = first_intid; i < num + first_intid; i++) diff --git a/tools/testing/selftests/kvm/include/aarch64/gic.h b/tools/testing/selftests/kvm/include/aarch64/gic.h index 9043eaef1076..f474714e4cb2 100644 --- a/tools/testing/selftests/kvm/include/aarch64/gic.h +++ b/tools/testing/selftests/kvm/include/aarch64/gic.h @@ -47,4 +47,7 @@ void gic_irq_clear_pending(unsigned int intid); bool gic_irq_get_pending(unsigned int intid); void gic_irq_set_config(unsigned int intid, bool is_edge); +/* Execute a Wait For Interrupt instruction. */ +void gic_wfi(void); + #endif /* SELFTEST_KVM_GIC_H */ diff --git a/tools/testing/selftests/kvm/lib/aarch64/gic.c b/tools/testing/selftests/kvm/lib/aarch64/gic.c index 9d15598d4e34..392e3f581ae0 100644 --- a/tools/testing/selftests/kvm/lib/aarch64/gic.c +++ b/tools/testing/selftests/kvm/lib/aarch64/gic.c @@ -164,3 +164,8 @@ void gic_irq_set_config(unsigned int intid, bool is_edge) GUEST_ASSERT(gic_common_ops); gic_common_ops->gic_irq_set_config(intid, is_edge); } + +void gic_wfi(void) +{ + asm volatile("wfi"); +}
Break up the asm instructions poking daifclr and daifset to handle interrupts. R_RBZYL specifies pending interrupts will be handle after context synchronization events such as an ISB. Introduce a function wrapper for the WFI instruction. Signed-off-by: Colton Lewis <coltonlewis@google.com> --- tools/testing/selftests/kvm/aarch64/vgic_irq.c | 12 ++++++------ tools/testing/selftests/kvm/include/aarch64/gic.h | 3 +++ tools/testing/selftests/kvm/lib/aarch64/gic.c | 5 +++++ 3 files changed, 14 insertions(+), 6 deletions(-)