x86: Tell irq work about self IPI support

x86 supports irq work self-IPIs when local apic is available. This is
partly known on runtime so lets implement arch_irq_work_has_interrupt()
accordingly.

This should be safely called after setup_arch().

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

diff --git a/arch/x86/include/asm/Kbuild b/arch/x86/include/asm/Kbuild
index 8fa909cc655368d088401f53406f280e6460c96a..3bf000fab0aeb51b3fa23bfa1faca8b3a581febc 100644 (file)
--- a/arch/x86/include/asm/Kbuild
+++ b/arch/x86/include/asm/Kbuild
@@ -7,6 +7,5 @@ genhdr-y += unistd_x32.h
 generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += early_ioremap.h
-generic-y += irq_work.h
 generic-y += mcs_spinlock.h
 generic-y += scatterlist.h

diff --git a/arch/x86/include/asm/irq_work.h b/arch/x86/include/asm/irq_work.h
new file mode 100644 (file)
index 0000000..78162f8
--- /dev/null
+++ b/arch/x86/include/asm/irq_work.h
@@ -0,0 +1,11 @@
+#ifndef _ASM_IRQ_WORK_H
+#define _ASM_IRQ_WORK_H
+
+#include <asm/processor.h>
+
+static inline bool arch_irq_work_has_interrupt(void)
+{
+       return cpu_has_apic;
+}
+
+#endif /* _ASM_IRQ_WORK_H */

diff --git a/arch/x86/kernel/irq_work.c b/arch/x86/kernel/irq_work.c
index 1de84e3ab4e0737df845648aad772e815908c2f8..15d741ddfeeb7c4497e28052e1ad7ea08e68c252 100644 (file)
--- a/arch/x86/kernel/irq_work.c
+++ b/arch/x86/kernel/irq_work.c
@@ -41,7 +41,7 @@ __visible void smp_trace_irq_work_interrupt(struct pt_regs *regs)
 void arch_irq_work_raise(void)
 {
 #ifdef CONFIG_X86_LOCAL_APIC
-       if (!cpu_has_apic)
+       if (!arch_irq_work_has_interrupt())
                return;
 
        apic->send_IPI_self(IRQ_WORK_VECTOR);