[RFC][PATCH 3/5] static_call: Remove static_call_cond() and its usages

From: Josh Poimboeuf
Date: Fri Mar 10 2023 - 15:34:03 EST


static_call_cond() is now identical to static_call(). All static calls
to NULL function pointers are now NOPs for all configs. Replace all
static_call_cond() usages and remove it.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
arch/x86/events/core.c | 24 +++++++++++------------
arch/x86/include/asm/kvm-x86-ops.h | 3 +--
arch/x86/include/asm/kvm-x86-pmu-ops.h | 3 +--
arch/x86/include/asm/kvm_host.h | 4 ++--
arch/x86/kvm/irq.c | 2 +-
arch/x86/kvm/lapic.c | 22 ++++++++++-----------
arch/x86/kvm/pmu.c | 4 ++--
arch/x86/kvm/x86.c | 24 +++++++++++------------
include/linux/static_call.h | 7 -------
security/keys/trusted-keys/trusted_core.c | 2 +-
10 files changed, 43 insertions(+), 52 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index d096b04bf80e..c94537501091 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -995,7 +995,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
if (cpuc->txn_flags & PERF_PMU_TXN_ADD)
n0 -= cpuc->n_txn;

- static_call_cond(x86_pmu_start_scheduling)(cpuc);
+ static_call(x86_pmu_start_scheduling)(cpuc);

for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) {
c = cpuc->event_constraint[i];
@@ -1094,7 +1094,7 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
*/
if (!unsched && assign) {
for (i = 0; i < n; i++)
- static_call_cond(x86_pmu_commit_scheduling)(cpuc, i, assign[i]);
+ static_call(x86_pmu_commit_scheduling)(cpuc, i, assign[i]);
} else {
for (i = n0; i < n; i++) {
e = cpuc->event_list[i];
@@ -1102,13 +1102,13 @@ int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
/*
* release events that failed scheduling
*/
- static_call_cond(x86_pmu_put_event_constraints)(cpuc, e);
+ static_call(x86_pmu_put_event_constraints)(cpuc, e);

cpuc->event_constraint[i] = NULL;
}
}

- static_call_cond(x86_pmu_stop_scheduling)(cpuc);
+ static_call(x86_pmu_stop_scheduling)(cpuc);

return unsched ? -EINVAL : 0;
}
@@ -1221,7 +1221,7 @@ static inline void x86_assign_hw_event(struct perf_event *event,
hwc->last_cpu = smp_processor_id();
hwc->last_tag = ++cpuc->tags[i];

- static_call_cond(x86_pmu_assign)(event, idx);
+ static_call(x86_pmu_assign)(event, idx);

switch (hwc->idx) {
case INTEL_PMC_IDX_FIXED_BTS:
@@ -1399,7 +1399,7 @@ int x86_perf_event_set_period(struct perf_event *event)
if (left > x86_pmu.max_period)
left = x86_pmu.max_period;

- static_call_cond(x86_pmu_limit_period)(event, &left);
+ static_call(x86_pmu_limit_period)(event, &left);

this_cpu_write(pmc_prev_left[idx], left);

@@ -1487,7 +1487,7 @@ static int x86_pmu_add(struct perf_event *event, int flags)
* This is before x86_pmu_enable() will call x86_pmu_start(),
* so we enable LBRs before an event needs them etc..
*/
- static_call_cond(x86_pmu_add)(event);
+ static_call(x86_pmu_add)(event);

ret = 0;
out:
@@ -1640,7 +1640,7 @@ static void x86_pmu_del(struct perf_event *event, int flags)
if (i >= cpuc->n_events - cpuc->n_added)
--cpuc->n_added;

- static_call_cond(x86_pmu_put_event_constraints)(cpuc, event);
+ static_call(x86_pmu_put_event_constraints)(cpuc, event);

/* Delete the array entry. */
while (++i < cpuc->n_events) {
@@ -1660,7 +1660,7 @@ static void x86_pmu_del(struct perf_event *event, int flags)
* This is after x86_pmu_stop(); so we disable LBRs after any
* event can need them etc..
*/
- static_call_cond(x86_pmu_del)(event);
+ static_call(x86_pmu_del)(event);
}

int x86_pmu_handle_irq(struct pt_regs *regs)
@@ -2627,13 +2627,13 @@ static const struct attribute_group *x86_pmu_attr_groups[] = {

static void x86_pmu_sched_task(struct perf_event_pmu_context *pmu_ctx, bool sched_in)
{
- static_call_cond(x86_pmu_sched_task)(pmu_ctx, sched_in);
+ static_call(x86_pmu_sched_task)(pmu_ctx, sched_in);
}

static void x86_pmu_swap_task_ctx(struct perf_event_pmu_context *prev_epc,
struct perf_event_pmu_context *next_epc)
{
- static_call_cond(x86_pmu_swap_task_ctx)(prev_epc, next_epc);
+ static_call(x86_pmu_swap_task_ctx)(prev_epc, next_epc);
}

void perf_check_microcode(void)
@@ -2672,7 +2672,7 @@ static bool x86_pmu_filter(struct pmu *pmu, int cpu)
{
bool ret = false;

- static_call_cond(x86_pmu_filter)(pmu, cpu, &ret);
+ static_call(x86_pmu_filter)(pmu, cpu, &ret);

return ret;
}
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 8dc345cc6318..2f0bfd910637 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -9,8 +9,7 @@ BUILD_BUG_ON(1)
* "static_call_update()" calls.
*
* KVM_X86_OP_OPTIONAL() can be used for those functions that can have
- * a NULL definition, for example if "static_call_cond()" will be used
- * at the call sites. KVM_X86_OP_OPTIONAL_RET0() can be used likewise
+ * a NULL definition. KVM_X86_OP_OPTIONAL_RET0() can be used likewise
* to make a definition optional, but in this case the default will
* be __static_call_return0.
*/
diff --git a/arch/x86/include/asm/kvm-x86-pmu-ops.h b/arch/x86/include/asm/kvm-x86-pmu-ops.h
index c17e3e96fc1d..6815319c4ff3 100644
--- a/arch/x86/include/asm/kvm-x86-pmu-ops.h
+++ b/arch/x86/include/asm/kvm-x86-pmu-ops.h
@@ -9,8 +9,7 @@ BUILD_BUG_ON(1)
* "static_call_update()" calls.
*
* KVM_X86_PMU_OP_OPTIONAL() can be used for those functions that can have
- * a NULL definition, for example if "static_call_cond()" will be used
- * at the call sites.
+ * a NULL definition.
*/
KVM_X86_PMU_OP(hw_event_available)
KVM_X86_PMU_OP(pmc_is_enabled)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 808c292ad3f4..1dfba499d3e5 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2172,12 +2172,12 @@ static inline bool kvm_irq_is_postable(struct kvm_lapic_irq *irq)

static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
{
- static_call_cond(kvm_x86_vcpu_blocking)(vcpu);
+ static_call(kvm_x86_vcpu_blocking)(vcpu);
}

static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
- static_call_cond(kvm_x86_vcpu_unblocking)(vcpu);
+ static_call(kvm_x86_vcpu_unblocking)(vcpu);
}

static inline int kvm_cpu_get_apicid(int mps_cpu)
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index b2c397dd2bc6..4f9e090c9d42 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -155,7 +155,7 @@ void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
{
__kvm_migrate_apic_timer(vcpu);
__kvm_migrate_pit_timer(vcpu);
- static_call_cond(kvm_x86_migrate_timers)(vcpu);
+ static_call(kvm_x86_migrate_timers)(vcpu);
}

bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index e542cf285b51..d5f7e829d975 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -681,8 +681,8 @@ static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
if (unlikely(apic->apicv_active)) {
/* need to update RVI */
kvm_lapic_clear_vector(vec, apic->regs + APIC_IRR);
- static_call_cond(kvm_x86_hwapic_irr_update)(apic->vcpu,
- apic_find_highest_irr(apic));
+ static_call(kvm_x86_hwapic_irr_update)(apic->vcpu,
+ apic_find_highest_irr(apic));
} else {
apic->irr_pending = false;
kvm_lapic_clear_vector(vec, apic->regs + APIC_IRR);
@@ -708,7 +708,7 @@ static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
* just set SVI.
*/
if (unlikely(apic->apicv_active))
- static_call_cond(kvm_x86_hwapic_isr_update)(vec);
+ static_call(kvm_x86_hwapic_isr_update)(vec);
else {
++apic->isr_count;
BUG_ON(apic->isr_count > MAX_APIC_VECTOR);
@@ -753,7 +753,7 @@ static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
* and must be left alone.
*/
if (unlikely(apic->apicv_active))
- static_call_cond(kvm_x86_hwapic_isr_update)(apic_find_highest_isr(apic));
+ static_call(kvm_x86_hwapic_isr_update)(apic_find_highest_isr(apic));
else {
--apic->isr_count;
BUG_ON(apic->isr_count < 0);
@@ -2519,7 +2519,7 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)

if ((old_value ^ value) & (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE)) {
kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
- static_call_cond(kvm_x86_set_virtual_apic_mode)(vcpu);
+ static_call(kvm_x86_set_virtual_apic_mode)(vcpu);
}

apic->base_address = apic->vcpu->arch.apic_base &
@@ -2682,9 +2682,9 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
vcpu->arch.pv_eoi.msr_val = 0;
apic_update_ppr(apic);
if (apic->apicv_active) {
- static_call_cond(kvm_x86_apicv_post_state_restore)(vcpu);
- static_call_cond(kvm_x86_hwapic_irr_update)(vcpu, -1);
- static_call_cond(kvm_x86_hwapic_isr_update)(-1);
+ static_call(kvm_x86_apicv_post_state_restore)(vcpu);
+ static_call(kvm_x86_hwapic_irr_update)(vcpu, -1);
+ static_call(kvm_x86_hwapic_isr_update)(-1);
}

vcpu->arch.apic_arb_prio = 0;
@@ -2961,9 +2961,9 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s)
kvm_lapic_set_reg(apic, APIC_TMCCT, 0);
kvm_apic_update_apicv(vcpu);
if (apic->apicv_active) {
- static_call_cond(kvm_x86_apicv_post_state_restore)(vcpu);
- static_call_cond(kvm_x86_hwapic_irr_update)(vcpu, apic_find_highest_irr(apic));
- static_call_cond(kvm_x86_hwapic_isr_update)(apic_find_highest_isr(apic));
+ static_call(kvm_x86_apicv_post_state_restore)(vcpu);
+ static_call(kvm_x86_hwapic_irr_update)(vcpu, apic_find_highest_irr(apic));
+ static_call(kvm_x86_hwapic_isr_update)(apic_find_highest_isr(apic));
}
kvm_make_request(KVM_REQ_EVENT, vcpu);
if (ioapic_in_kernel(vcpu->kvm))
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 612e6c70ce2e..6accb46295a3 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -552,7 +552,7 @@ int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned idx, u64 *data)
void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu)
{
if (lapic_in_kernel(vcpu)) {
- static_call_cond(kvm_x86_pmu_deliver_pmi)(vcpu);
+ static_call(kvm_x86_pmu_deliver_pmi)(vcpu);
kvm_apic_local_deliver(vcpu->arch.apic, APIC_LVTPC);
}
}
@@ -632,7 +632,7 @@ void kvm_pmu_cleanup(struct kvm_vcpu *vcpu)
pmc_stop_counter(pmc);
}

- static_call_cond(kvm_x86_pmu_cleanup)(vcpu);
+ static_call(kvm_x86_pmu_cleanup)(vcpu);

bitmap_zero(pmu->pmc_in_use, X86_PMC_IDX_MAX);
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7713420abab0..fcf845fc5770 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4845,7 +4845,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
struct kvm_lapic_state *s)
{
- static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
+ static_call(kvm_x86_sync_pir_to_irr)(vcpu);

return kvm_apic_get_state(vcpu, s);
}
@@ -8948,7 +8948,7 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
kvm_rip_write(vcpu, ctxt->eip);
if (r && (ctxt->tf || (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)))
r = kvm_vcpu_do_singlestep(vcpu);
- static_call_cond(kvm_x86_update_emulated_instruction)(vcpu);
+ static_call(kvm_x86_update_emulated_instruction)(vcpu);
__kvm_set_rflags(vcpu, ctxt->eflags);
}

@@ -10307,7 +10307,7 @@ static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
if (irqchip_split(vcpu->kvm))
kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors);
else {
- static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
+ static_call(kvm_x86_sync_pir_to_irr)(vcpu);
if (ioapic_in_kernel(vcpu->kvm))
kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors);
}
@@ -10329,11 +10329,11 @@ static void vcpu_load_eoi_exitmap(struct kvm_vcpu *vcpu)
bitmap_or((ulong *)eoi_exit_bitmap,
vcpu->arch.ioapic_handled_vectors,
to_hv_synic(vcpu)->vec_bitmap, 256);
- static_call_cond(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap);
+ static_call(kvm_x86_load_eoi_exitmap)(vcpu, eoi_exit_bitmap);
return;
}

- static_call_cond(kvm_x86_load_eoi_exitmap)(
+ static_call(kvm_x86_load_eoi_exitmap)(
vcpu, (u64 *)vcpu->arch.ioapic_handled_vectors);
}

@@ -10353,7 +10353,7 @@ void kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,

void kvm_arch_guest_memory_reclaimed(struct kvm *kvm)
{
- static_call_cond(kvm_x86_guest_memory_reclaimed)(kvm);
+ static_call(kvm_x86_guest_memory_reclaimed)(kvm);
}

static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
@@ -10361,7 +10361,7 @@ static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
if (!lapic_in_kernel(vcpu))
return;

- static_call_cond(kvm_x86_set_apic_access_page_addr)(vcpu);
+ static_call(kvm_x86_set_apic_access_page_addr)(vcpu);
}

void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu)
@@ -10603,7 +10603,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
* i.e. they can post interrupts even if APICv is temporarily disabled.
*/
if (kvm_lapic_enabled(vcpu))
- static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
+ static_call(kvm_x86_sync_pir_to_irr)(vcpu);

if (kvm_vcpu_exit_request(vcpu)) {
vcpu->mode = OUTSIDE_GUEST_MODE;
@@ -10654,7 +10654,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
break;

if (kvm_lapic_enabled(vcpu))
- static_call_cond(kvm_x86_sync_pir_to_irr)(vcpu);
+ static_call(kvm_x86_sync_pir_to_irr)(vcpu);

if (unlikely(kvm_vcpu_exit_request(vcpu))) {
exit_fastpath = EXIT_FASTPATH_EXIT_HANDLED;
@@ -11392,7 +11392,7 @@ static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs,
*mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
vcpu->arch.cr3 = sregs->cr3;
kvm_register_mark_dirty(vcpu, VCPU_EXREG_CR3);
- static_call_cond(kvm_x86_post_set_cr3)(vcpu, sregs->cr3);
+ static_call(kvm_x86_post_set_cr3)(vcpu, sregs->cr3);

kvm_set_cr8(vcpu, sregs->cr8);

@@ -12361,7 +12361,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
mutex_unlock(&kvm->slots_lock);
}
kvm_unload_vcpu_mmus(kvm);
- static_call_cond(kvm_x86_vm_destroy)(kvm);
+ static_call(kvm_x86_vm_destroy)(kvm);
kvm_free_msr_filter(srcu_dereference_check(kvm->arch.msr_filter, &kvm->srcu, 1));
kvm_pic_destroy(kvm);
kvm_ioapic_destroy(kvm);
@@ -13049,7 +13049,7 @@ bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu)
void kvm_arch_start_assignment(struct kvm *kvm)
{
if (atomic_inc_return(&kvm->arch.assigned_device_count) == 1)
- static_call_cond(kvm_x86_pi_start_assignment)(kvm);
+ static_call(kvm_x86_pi_start_assignment)(kvm);
}
EXPORT_SYMBOL_GPL(kvm_arch_start_assignment);

diff --git a/include/linux/static_call.h b/include/linux/static_call.h
index 58783d112df5..3b3e9e9a1582 100644
--- a/include/linux/static_call.h
+++ b/include/linux/static_call.h
@@ -22,7 +22,6 @@
* __static_call_return0;
*
* static_call(name)(args...);
- * static_call_cond(name)(args...);
* static_call_update(name, func);
* static_call_query(name);
*
@@ -174,8 +173,6 @@ extern int static_call_text_reserved(void *start, void *end);

#define DEFINE_STATIC_CALL_RET0 DEFINE_STATIC_CALL_NULL

-#define static_call_cond(name) __static_call(name)
-
#define EXPORT_STATIC_CALL(name) \
EXPORT_SYMBOL(STATIC_CALL_KEY(name)); \
EXPORT_SYMBOL(STATIC_CALL_TRAMP(name))
@@ -211,8 +208,6 @@ static inline int static_call_init(void) { return 0; }

#define DEFINE_STATIC_CALL_RET0 DEFINE_STATIC_CALL_NULL

-#define static_call_cond(name) __static_call(name)
-
static inline
void __static_call_update(struct static_call_key *key, void *tramp, void *func)
{
@@ -258,8 +253,6 @@ static inline int static_call_init(void) { return 0; }

#define DEFINE_STATIC_CALL_RET0 DEFINE_STATIC_CALL_NULL

-#define static_call_cond(name) static_call(name)
-
static inline
void __static_call_update(struct static_call_key *key, void *tramp, void *func)
{
diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c
index c6fc50d67214..b7920482ebcb 100644
--- a/security/keys/trusted-keys/trusted_core.c
+++ b/security/keys/trusted-keys/trusted_core.c
@@ -388,7 +388,7 @@ static int __init init_trusted(void)

static void __exit cleanup_trusted(void)
{
- static_call_cond(trusted_key_exit)();
+ static_call(trusted_key_exit)();
}

late_initcall(init_trusted);
--
2.39.2