diff options
Diffstat (limited to 'arch/x86/kernel')
| -rw-r--r-- | arch/x86/kernel/tracepoint.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/x86/kernel/tracepoint.c b/arch/x86/kernel/tracepoint.c index 15515132bf0d..dd4aa04bb95c 100644 --- a/arch/x86/kernel/tracepoint.c +++ b/arch/x86/kernel/tracepoint.c @@ -4,9 +4,11 @@ * Copyright (C) 2013 Seiji Aguchi <seiji.aguchi@hds.com> * */ +#include <linux/jump_label.h> +#include <linux/atomic.h> + #include <asm/hw_irq.h> #include <asm/desc.h> -#include <linux/atomic.h> atomic_t trace_idt_ctr = ATOMIC_INIT(0); struct desc_ptr trace_idt_descr = { NR_VECTORS * 16 - 1, @@ -15,6 +17,7 @@ struct desc_ptr trace_idt_descr = { NR_VECTORS * 16 - 1, /* No need to be aligned, but done to keep all IDTs defined the same way. */ gate_desc trace_idt_table[NR_VECTORS] __page_aligned_bss; +DEFINE_STATIC_KEY_FALSE(trace_irqvectors_key); static int trace_irq_vector_refcount; static DEFINE_MUTEX(irq_vector_mutex); @@ -36,6 +39,8 @@ static void switch_idt(void *arg) int trace_irq_vector_regfunc(void) { + static_branch_inc(&trace_irqvectors_key); + mutex_lock(&irq_vector_mutex); if (!trace_irq_vector_refcount) { set_trace_idt_ctr(1); @@ -49,6 +54,8 @@ int trace_irq_vector_regfunc(void) void trace_irq_vector_unregfunc(void) { + static_branch_dec(&trace_irqvectors_key); + mutex_lock(&irq_vector_mutex); trace_irq_vector_refcount--; if (!trace_irq_vector_refcount) { |