Oliver Upton <oliver.upton@xxxxxxxxx> writes:
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.
I'll change that.
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@xxxxxxxxxx>
---
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.
Apologies if I missed it. I'll remove gic_from the name.
