[tip: x86/apic] x86/apic: Remove pointless arguments from [native_]eoi_write()

From: tip-bot2 for Thomas Gleixner
Date: Wed Aug 09 2023 - 16:36:39 EST

The following commit has been merged into the x86/apic branch of tip:

Commit-ID: 185c8f33a048bd04fdedd08e7bd7861a85158834
Gitweb: https://git.kernel.org/tip/185c8f33a048bd04fdedd08e7bd7861a85158834
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Tue, 08 Aug 2023 15:04:15 -07:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Wed, 09 Aug 2023 11:58:33 -07:00

x86/apic: Remove pointless arguments from [native_]eoi_write()

Every callsite hands in the same constants which is a pointless exercise
and cannot be optimized by the compiler due to the indirect calls.

Use the constants in the eoi() callbacks and remove the arguments.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Reviewed-by: Wei Liu <wei.liu@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Tested-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
Tested-by: Juergen Gross <jgross@xxxxxxxx> # Xen PV (dom0 and unpriv. guest)
---
arch/x86/hyperv/hv_apic.c | 6 +++---
arch/x86/include/asm/apic.h | 17 +++++++++++------
arch/x86/kernel/apic/apic.c | 8 ++++----
arch/x86/kernel/apic/apic_flat_64.c | 4 ++--
arch/x86/kernel/apic/apic_noop.c | 3 ++-
arch/x86/kernel/apic/apic_numachip.c | 4 ++--
arch/x86/kernel/apic/bigsmp_32.c | 2 +-
arch/x86/kernel/apic/probe_32.c | 2 +-
arch/x86/kernel/apic/x2apic_cluster.c | 2 +-
arch/x86/kernel/apic/x2apic_phys.c | 2 +-
arch/x86/kernel/apic/x2apic_uv_x.c | 2 +-
arch/x86/kernel/kvm.c | 6 +++---
arch/x86/xen/apic.c | 7 ++++++-
13 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/arch/x86/hyperv/hv_apic.c b/arch/x86/hyperv/hv_apic.c
index 1fbda2f..5513f60 100644
--- a/arch/x86/hyperv/hv_apic.c
+++ b/arch/x86/hyperv/hv_apic.c
@@ -86,14 +86,14 @@ static void hv_apic_write(u32 reg, u32 val)
}
}

-static void hv_apic_eoi_write(u32 reg, u32 val)
+static void hv_apic_eoi_write(void)
{
struct hv_vp_assist_page *hvp = hv_vp_assist_page[smp_processor_id()];

if (hvp && (xchg(&hvp->apic_assist, 0) & 0x1))
return;

- wrmsr(HV_X64_MSR_EOI, val, 0);
+ wrmsr(HV_X64_MSR_EOI, APIC_EOI_ACK, 0);
}

static bool cpu_is_self(int cpu)
@@ -310,7 +310,7 @@ void __init hv_apic_init(void)
* lazy EOI when available, but the same accessor works for
* both xapic and x2apic because the field layout is the same.
*/
- apic_set_eoi_write(hv_apic_eoi_write);
+ apic_set_eoi_cb(hv_apic_eoi_write);
if (!x2apic_enabled()) {
apic->read = hv_apic_read;
apic->write = hv_apic_write;
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index ccf4e36..790f15d 100644
--- a/arch/x86/include/asm/apic.h
+++ b/arch/x86/include/asm/apic.h
@@ -98,6 +98,11 @@ static inline u32 native_apic_mem_read(u32 reg)
return *((volatile u32 *)(APIC_BASE + reg));
}

+static inline void native_apic_mem_eoi(void)
+{
+ native_apic_mem_write(APIC_EOI, APIC_EOI_ACK);
+}
+
extern void native_apic_icr_write(u32 low, u32 id);
extern u64 native_apic_icr_read(void);

@@ -189,7 +194,7 @@ static inline void native_apic_msr_write(u32 reg, u32 v)
wrmsr(APIC_BASE_MSR + (reg >> 4), v, 0);
}

-static inline void native_apic_msr_eoi_write(u32 reg, u32 v)
+static inline void native_apic_msr_eoi(void)
{
__wrmsr(APIC_BASE_MSR + (APIC_EOI >> 4), APIC_EOI_ACK, 0);
}
@@ -250,8 +255,8 @@ struct irq_data;
*/
struct apic {
/* Hotpath functions first */
- void (*eoi_write)(u32 reg, u32 v);
- void (*native_eoi_write)(u32 reg, u32 v);
+ void (*eoi)(void);
+ void (*native_eoi)(void);
void (*write)(u32 reg, u32 v);
u32 (*read)(u32 reg);

@@ -351,7 +356,7 @@ static inline void apic_write(u32 reg, u32 val)

static inline void apic_eoi(void)
{
- apic->eoi_write(APIC_EOI, APIC_EOI_ACK);
+ apic->eoi();
}

static inline u64 apic_icr_read(void)
@@ -380,7 +385,7 @@ static inline bool apic_id_valid(u32 apic_id)
return apic_id <= apic->max_apic_id;
}

-extern void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v));
+extern void __init apic_set_eoi_cb(void (*eoi)(void));

#else /* CONFIG_X86_LOCAL_APIC */

@@ -391,7 +396,7 @@ static inline u64 apic_icr_read(void) { return 0; }
static inline void apic_icr_write(u32 low, u32 high) { }
static inline void apic_wait_icr_idle(void) { }
static inline u32 safe_apic_wait_icr_idle(void) { return 0; }
-static inline void apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v)) {}
+static inline void apic_set_eoi_cb(void (*eoi)(void)) {}

#endif /* CONFIG_X86_LOCAL_APIC */

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 80a31f2..33d5ed6 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2502,15 +2502,15 @@ void __init acpi_wake_cpu_handler_update(wakeup_cpu_handler handler)
* interrupts disabled, so we know this does not race with actual APIC driver
* use.
*/
-void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
+void __init apic_set_eoi_cb(void (*eoi)(void))
{
struct apic **drv;

for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
/* Should happen once for each apic */
- WARN_ON((*drv)->eoi_write == eoi_write);
- (*drv)->native_eoi_write = (*drv)->eoi_write;
- (*drv)->eoi_write = eoi_write;
+ WARN_ON((*drv)->eoi == eoi);
+ (*drv)->native_eoi = (*drv)->eoi;
+ (*drv)->eoi = eoi;
}
}

diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c
index f65419d..5ce1b37 100644
--- a/arch/x86/kernel/apic/apic_flat_64.c
+++ b/arch/x86/kernel/apic/apic_flat_64.c
@@ -106,7 +106,7 @@ static struct apic apic_flat __ro_after_init = {

.read = native_apic_mem_read,
.write = native_apic_mem_write,
- .eoi_write = native_apic_mem_write,
+ .eoi = native_apic_mem_eoi,
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
@@ -182,7 +182,7 @@ static struct apic apic_physflat __ro_after_init = {

.read = native_apic_mem_read,
.write = native_apic_mem_write,
- .eoi_write = native_apic_mem_write,
+ .eoi = native_apic_mem_eoi,
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
index e33bea0..966d7cf 100644
--- a/arch/x86/kernel/apic/apic_noop.c
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -29,6 +29,7 @@ static int noop_wakeup_secondary_cpu(int apicid, unsigned long start_eip) { retu
static u64 noop_apic_icr_read(void) { return 0; }
static int noop_phys_pkg_id(int cpuid_apic, int index_msb) { return 0; }
static unsigned int noop_get_apic_id(unsigned long x) { return 0; }
+static void noop_apic_eoi(void) { }

static u32 noop_apic_read(u32 reg)
{
@@ -71,7 +72,7 @@ struct apic apic_noop __ro_after_init = {

.read = noop_apic_read,
.write = noop_apic_write,
- .eoi_write = noop_apic_write,
+ .eoi = noop_apic_eoi,
.icr_read = noop_apic_icr_read,
.icr_write = noop_apic_icr_write,
};
diff --git a/arch/x86/kernel/apic/apic_numachip.c b/arch/x86/kernel/apic/apic_numachip.c
index 9df0187..63f3d7b 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -247,7 +247,7 @@ static const struct apic apic_numachip1 __refconst = {

.read = native_apic_mem_read,
.write = native_apic_mem_write,
- .eoi_write = native_apic_mem_write,
+ .eoi = native_apic_mem_eoi,
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
};
@@ -284,7 +284,7 @@ static const struct apic apic_numachip2 __refconst = {

.read = native_apic_mem_read,
.write = native_apic_mem_write,
- .eoi_write = native_apic_mem_write,
+ .eoi = native_apic_mem_eoi,
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
};
diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c
index ffcd114..23c29a0 100644
--- a/arch/x86/kernel/apic/bigsmp_32.c
+++ b/arch/x86/kernel/apic/bigsmp_32.c
@@ -105,7 +105,7 @@ static struct apic apic_bigsmp __ro_after_init = {

.read = native_apic_mem_read,
.write = native_apic_mem_write,
- .eoi_write = native_apic_mem_write,
+ .eoi = native_apic_mem_eoi,
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index 5facf42..3671cc1 100644
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -60,7 +60,7 @@ static struct apic apic_default __ro_after_init = {

.read = native_apic_mem_read,
.write = native_apic_mem_write,
- .eoi_write = native_apic_mem_write,
+ .eoi = native_apic_mem_eoi,
.icr_read = native_apic_icr_read,
.icr_write = native_apic_icr_write,
.wait_icr_idle = apic_mem_wait_icr_idle,
diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c
index 12b9c31..affbff6 100644
--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -254,7 +254,7 @@ static struct apic apic_x2apic_cluster __ro_after_init = {

.read = native_apic_msr_read,
.write = native_apic_msr_write,
- .eoi_write = native_apic_msr_eoi_write,
+ .eoi = native_apic_msr_eoi,
.icr_read = native_x2apic_icr_read,
.icr_write = native_x2apic_icr_write,
};
diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c
index 47ee5c6..788cdb4 100644
--- a/arch/x86/kernel/apic/x2apic_phys.c
+++ b/arch/x86/kernel/apic/x2apic_phys.c
@@ -169,7 +169,7 @@ static struct apic apic_x2apic_phys __ro_after_init = {

.read = native_apic_msr_read,
.write = native_apic_msr_write,
- .eoi_write = native_apic_msr_eoi_write,
+ .eoi = native_apic_msr_eoi,
.icr_read = native_x2apic_icr_read,
.icr_write = native_x2apic_icr_write,
};
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 5692514..1cedb25 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -831,7 +831,7 @@ static struct apic apic_x2apic_uv_x __ro_after_init = {

.read = native_apic_msr_read,
.write = native_apic_msr_write,
- .eoi_write = native_apic_msr_eoi_write,
+ .eoi = native_apic_msr_eoi,
.icr_read = native_x2apic_icr_read,
.icr_write = native_x2apic_icr_write,
};
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 1cceac5..c2e3e7a 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -332,7 +332,7 @@ static void kvm_register_steal_time(void)

static DEFINE_PER_CPU_DECRYPTED(unsigned long, kvm_apic_eoi) = KVM_PV_EOI_DISABLED;

-static notrace void kvm_guest_apic_eoi_write(u32 reg, u32 val)
+static notrace void kvm_guest_apic_eoi_write(void)
{
/**
* This relies on __test_and_clear_bit to modify the memory
@@ -343,7 +343,7 @@ static notrace void kvm_guest_apic_eoi_write(u32 reg, u32 val)
*/
if (__test_and_clear_bit(KVM_PV_EOI_BIT, this_cpu_ptr(&kvm_apic_eoi)))
return;
- apic->native_eoi_write(APIC_EOI, APIC_EOI_ACK);
+ apic->native_eoi();
}

static void kvm_guest_cpu_init(void)
@@ -825,7 +825,7 @@ static void __init kvm_guest_init(void)
}

if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
- apic_set_eoi_write(kvm_guest_apic_eoi_write);
+ apic_set_eoi_cb(kvm_guest_apic_eoi_write);

if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF_INT) && kvmapf) {
static_branch_enable(&kvm_async_pf_enabled);
diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index 661eecf..804a26b 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -81,6 +81,11 @@ static void xen_apic_write(u32 reg, u32 val)
WARN(1,"register: %x, value: %x\n", reg, val);
}

+static void xen_apic_eoi(void)
+{
+ WARN_ON_ONCE(1);
+}
+
static u64 xen_apic_icr_read(void)
{
return 0;
@@ -147,7 +152,7 @@ static struct apic xen_pv_apic = {
#endif
.read = xen_apic_read,
.write = xen_apic_write,
- .eoi_write = xen_apic_write,
+ .eoi = xen_apic_eoi,

.icr_read = xen_apic_icr_read,
.icr_write = xen_apic_icr_write,