[PATCH 1/3] x86/apic: Drop apic::delivery_mode

From: Andrew Cooper
Date: Thu Nov 02 2023 - 08:27:50 EST


This field is set to APIC_DELIVERY_MODE_FIXED in all cases, and is read
exactly once. Fold the constant in uv_program_mmr() and drop the field.

Searching for the origin of the stale HyperV comment reveals commit
a31e58e129f7 ("x86/apic: Switch all APICs to Fixed delivery mode") which
notes:

As a consequence of this change, the apic::irq_delivery_mode field is
now pointless, but this needs to be cleaned up in a separate patch.

6 years is long enough for this technical debt to have survived.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
arch/x86/include/asm/apic.h | 2 --
arch/x86/kernel/apic/apic_flat_64.c | 2 --
arch/x86/kernel/apic/apic_noop.c | 1 -
arch/x86/kernel/apic/apic_numachip.c | 2 --
arch/x86/kernel/apic/bigsmp_32.c | 1 -
arch/x86/kernel/apic/probe_32.c | 1 -
arch/x86/kernel/apic/x2apic_cluster.c | 1 -
arch/x86/kernel/apic/x2apic_phys.c | 1 -
arch/x86/kernel/apic/x2apic_uv_x.c | 1 -
arch/x86/platform/uv/uv_irq.c | 2 +-
drivers/pci/controller/pci-hyperv.c | 7 -------
11 files changed, 1 insertion(+), 20 deletions(-)

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 5af4ec1a0f71..841afbd7bfe7 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -272,8 +272,6 @@ struct apic {
void (*send_IPI_all)(int vector);
void (*send_IPI_self)(int vector);

- enum apic_delivery_modes delivery_mode;
-
u32 disable_esr : 1,
dest_mode_logical : 1,
x2apic_set_max_apicid : 1;
diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index 032a84e2c3cc..e526b226910b 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -82,7 +82,6 @@ static struct apic apic_flat __ro_after_init = {
.acpi_madt_oem_check = flat_acpi_madt_oem_check,
.apic_id_registered = default_apic_id_registered,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = true,

.disable_esr = 0,
@@ -153,7 +152,6 @@ static struct apic apic_physflat __ro_after_init = {
.acpi_madt_oem_check = physflat_acpi_madt_oem_check,
.apic_id_registered = default_apic_id_registered,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = false,

.disable_esr = 0,
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
index 966d7cf10b95..70e7dfc3cc84 100644
--- a/arch/x86/kernel/apic/apic_noop.c
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -45,7 +45,6 @@ static void noop_apic_write(u32 reg, u32 val)
struct apic apic_noop __ro_after_init = {
.name = "noop",

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = true,

.disable_esr = 0,
diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index 63f3d7be9dc7..8f5a42ad1f9f 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -222,7 +222,6 @@ static const struct apic apic_numachip1 __refconst = {
.probe = numachip1_probe,
.acpi_madt_oem_check = numachip1_acpi_madt_oem_check,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = false,

.disable_esr = 0,
@@ -259,7 +258,6 @@ static const struct apic apic_numachip2 __refconst = {
.probe = numachip2_probe,
.acpi_madt_oem_check = numachip2_acpi_madt_oem_check,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = false,

.disable_esr = 0,
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index 0e5535add4b5..863c3002a574 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -80,7 +80,6 @@ static struct apic apic_bigsmp __ro_after_init = {
.name = "bigsmp",
.probe = probe_bigsmp,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = false,

.disable_esr = 1,
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 9a06df6cdd68..f851ccf1e14f 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -35,7 +35,6 @@ static struct apic apic_default __ro_after_init = {
.probe = probe_default,
.apic_id_registered = default_apic_id_registered,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = true,

.disable_esr = 0,
diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c
index affbff65e497..7d15f6c3b718 100644
--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -227,7 +227,6 @@ static struct apic apic_x2apic_cluster __ro_after_init = {
.probe = x2apic_cluster_probe,
.acpi_madt_oem_check = x2apic_acpi_madt_oem_check,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = true,

.disable_esr = 0,
diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
index 788cdb4ee394..8bb740e22b7d 100644
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -145,7 +145,6 @@ static struct apic apic_x2apic_phys __ro_after_init = {
.probe = x2apic_phys_probe,
.acpi_madt_oem_check = x2apic_acpi_madt_oem_check,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = false,

.disable_esr = 0,
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 7d304ef1a7f5..ae4f0c1a7b43 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -805,7 +805,6 @@ static struct apic apic_x2apic_uv_x __ro_after_init = {
.probe = uv_probe,
.acpi_madt_oem_check = uv_acpi_madt_oem_check,

- .delivery_mode = APIC_DELIVERY_MODE_FIXED,
.dest_mode_logical = false,

.disable_esr = 0,
diff --git a/arch/x86/platform/uv/uv_irq.c b/arch/x86/platform/uv/uv_irq.c
index 4221259a5870..a379501b7a69 100644
--- a/arch/x86/platform/uv/uv_irq.c
+++ b/arch/x86/platform/uv/uv_irq.c
@@ -35,7 +35,7 @@ static void uv_program_mmr(struct irq_cfg *cfg, struct uv_irq_2_mmr_pnode *info)
mmr_value = 0;
entry = (struct uv_IO_APIC_route_entry *)&mmr_value;
entry->vector = cfg->vector;
- entry->delivery_mode = apic->delivery_mode;
+ entry->delivery_mode = APIC_DELIVERY_MODE_FIXED;
entry->dest_mode = apic->dest_mode_logical;
entry->polarity = 0;
entry->trigger = 0;
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index bed3cefdaf19..f5d2ef8572e7 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -650,13 +650,6 @@ static void hv_arch_irq_unmask(struct irq_data *data)
PCI_FUNC(pdev->devfn);
params->int_target.vector = hv_msi_get_int_vector(data);

- /*
- * Honoring apic->delivery_mode set to APIC_DELIVERY_MODE_FIXED by
- * setting the HV_DEVICE_INTERRUPT_TARGET_MULTICAST flag results in a
- * spurious interrupt storm. Not doing so does not seem to have a
- * negative effect (yet?).
- */
-
if (hbus->protocol_version >= PCI_PROTOCOL_VERSION_1_2) {
/*
* PCI_PROTOCOL_VERSION_1_2 supports the VP_SET version of the

--
2.30.2