From 22ca7ee933a39f542ff6f81fc64f8036eff56519 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 22 Jul 2019 20:47:23 +0200 Subject: [PATCH] x86/apic: Provide and use helper for send_IPI_allbutself() To support IPI shorthands wrap invocations of apic->send_IPI_allbutself() in a helper function, so the static key controlling the shorthand mode is only in one place. Fixup all callers. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20190722105220.492691679@linutronix.de --- arch/x86/include/asm/apic.h | 2 ++ arch/x86/kernel/apic/ipi.c | 12 ++++++++++++ arch/x86/kernel/kgdb.c | 2 +- arch/x86/kernel/reboot.c | 7 +------ arch/x86/kernel/smp.c | 4 ++-- 5 files changed, 18 insertions(+), 9 deletions(-) diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index 4a0d349ab44d..de86c6c15228 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -177,6 +177,8 @@ extern void lapic_online(void); extern void lapic_offline(void); extern bool apic_needs_pit(void); +extern void apic_send_IPI_allbutself(unsigned int vector); + #else /* !CONFIG_X86_LOCAL_APIC */ static inline void lapic_shutdown(void) { } #define local_apic_timer_c2_ok 1 diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c index 5bd8a001a887..f53de3e0145e 100644 --- a/arch/x86/kernel/apic/ipi.c +++ b/arch/x86/kernel/apic/ipi.c @@ -50,6 +50,18 @@ void apic_smt_update(void) static_branch_enable(&apic_use_ipi_shorthand); } } + +void apic_send_IPI_allbutself(unsigned int vector) +{ + if (num_online_cpus() < 2) + return; + + if (static_branch_likely(&apic_use_ipi_shorthand)) + apic->send_IPI_allbutself(vector); + else + apic->send_IPI_mask_allbutself(cpu_online_mask, vector); +} + #endif /* CONFIG_SMP */ static inline int __prepare_ICR2(unsigned int mask) diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c index a53dfb09880f..c44fe7d8d9a4 100644 --- a/arch/x86/kernel/kgdb.c +++ b/arch/x86/kernel/kgdb.c @@ -416,7 +416,7 @@ static void kgdb_disable_hw_debug(struct pt_regs *regs) */ void kgdb_roundup_cpus(void) { - apic->send_IPI_allbutself(NMI_VECTOR); + apic_send_IPI_allbutself(NMI_VECTOR); } #endif diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 09d6bded3c1e..0cc7c0b106bb 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -828,11 +828,6 @@ static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) return NMI_HANDLED; } -static void smp_send_nmi_allbutself(void) -{ - apic->send_IPI_allbutself(NMI_VECTOR); -} - /* * Halt all other CPUs, calling the specified function on each of them * @@ -861,7 +856,7 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback) */ wmb(); - smp_send_nmi_allbutself(); + apic_send_IPI_allbutself(NMI_VECTOR); /* Kick CPUs looping in NMI context. */ WRITE_ONCE(crash_ipi_issued, 1); diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index 231fa230ebc7..b8ad1876a081 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c @@ -215,7 +215,7 @@ static void native_stop_other_cpus(int wait) /* sync above data before sending IRQ */ wmb(); - apic->send_IPI_allbutself(REBOOT_VECTOR); + apic_send_IPI_allbutself(REBOOT_VECTOR); /* * Don't wait longer than a second for IPI completion. The @@ -241,7 +241,7 @@ static void native_stop_other_cpus(int wait) pr_emerg("Shutting down cpus with NMI\n"); - apic->send_IPI_allbutself(NMI_VECTOR); + apic_send_IPI_allbutself(NMI_VECTOR); } /* * Don't wait longer than 10 ms if the caller didn't