[PATCH v6 04/10] hyperv: Introduce hv_recommend_using_aeoi()

From: Nuno Das Neves
Date: Fri Mar 14 2025 - 15:29:53 EST


Factor out the check for enabling auto eoi, to be reused in root
partition code.

No functional changes.

Signed-off-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Stanislav Kinsburskii <skinsburskii@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Easwar Hariharan <eahariha@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Michael Kelley <mhklinux@xxxxxxxxxxx>
Reviewed-by: Tianyu Lan <tiala@xxxxxxxxxxxxx>
---
drivers/hv/hv.c | 12 +-----------
include/asm-generic/mshyperv.h | 13 +++++++++++++
2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index a38f84548bc2..308c8f279df8 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -313,17 +313,7 @@ void hv_synic_enable_regs(unsigned int cpu)

shared_sint.vector = vmbus_interrupt;
shared_sint.masked = false;
-
- /*
- * On architectures where Hyper-V doesn't support AEOI (e.g., ARM64),
- * it doesn't provide a recommendation flag and AEOI must be disabled.
- */
-#ifdef HV_DEPRECATING_AEOI_RECOMMENDED
- shared_sint.auto_eoi =
- !(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED);
-#else
- shared_sint.auto_eoi = 0;
-#endif
+ shared_sint.auto_eoi = hv_recommend_using_aeoi();
hv_set_msr(HV_MSR_SINT0 + VMBUS_MESSAGE_SINT, shared_sint.as_uint64);

/* Enable the global synic bit */
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index c3697bc0598d..8519b8ec8e9d 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -77,6 +77,19 @@ u64 hv_do_fast_hypercall16(u16 control, u64 input1, u64 input2);
bool hv_isolation_type_snp(void);
bool hv_isolation_type_tdx(void);

+/*
+ * On architectures where Hyper-V doesn't support AEOI (e.g., ARM64),
+ * it doesn't provide a recommendation flag and AEOI must be disabled.
+ */
+static inline bool hv_recommend_using_aeoi(void)
+{
+#ifdef HV_DEPRECATING_AEOI_RECOMMENDED
+ return !(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED);
+#else
+ return false;
+#endif
+}
+
static inline struct hv_proximity_domain_info hv_numa_node_to_pxm_info(int node)
{
struct hv_proximity_domain_info pxm_info = {};
--
2.34.1