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 <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105220.492691679@linutronix.de

diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h
index 4a0d349ab44d867ed749f6057265133750c58f3f..de86c6c1522867c982b391989d6cb0984b6d4ab6 100644 (file)
--- 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 5bd8a001a887cc1efdff908023fae05ad6e15927..f53de3e0145ee9fc5c81eef6d29790ff2d1fb8bf 100644 (file)
--- 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 a53dfb09880f21f9b9150b8648df79bdd03a81d1..c44fe7d8d9a4e1e7a1701a697c42431b2dd8cea1 100644 (file)
--- 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 09d6bded3c1e569fbce3426ecfd10995212ec6e8..0cc7c0b106bbfa3d563f36bce2fe781726c830cf 100644 (file)
--- 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 231fa230ebc734989532551546d0ee53da67a17f..b8ad1876a0811b6cc19abe3f1524639af348251c 100644 (file)
--- 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