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| author | Seiji Aguchi <seiji.aguchi@hds.com> | 2013-06-20 17:45:44 +0200 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2013-06-21 07:25:13 +0200 |
| commit | 629f4f9d59a27d8e58aa612e886e6a9a63ea7aeb (patch) | |
| tree | 049f9d16e2c304a51fa62d47cde34af8b10fc65d /arch/x86/include/asm/desc.h | |
| parent | x86, trace: Introduce entering/exiting_irq() (diff) | |
| download | linux-629f4f9d59a27d8e58aa612e886e6a9a63ea7aeb.tar.xz linux-629f4f9d59a27d8e58aa612e886e6a9a63ea7aeb.zip | |
x86: Rename variables for debugging
Rename variables for debugging to describe meaning of them precisely.
Also, introduce a generic way to switch IDT by checking a current state,
debug on/off.
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/51C323A8.7050905@hds.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'arch/x86/include/asm/desc.h')
| -rw-r--r-- | arch/x86/include/asm/desc.h | 47 |
1 files changed, 44 insertions, 3 deletions
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index 8bf1c06070d5..af290b8f124a 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -36,8 +36,8 @@ static inline void fill_ldt(struct desc_struct *desc, const struct user_desc *in extern struct desc_ptr idt_descr; extern gate_desc idt_table[]; -extern struct desc_ptr nmi_idt_descr; -extern gate_desc nmi_idt_table[]; +extern struct desc_ptr debug_idt_descr; +extern gate_desc debug_idt_table[]; struct gdt_page { struct desc_struct gdt[GDT_ENTRIES]; @@ -316,7 +316,7 @@ static inline void set_nmi_gate(int gate, void *addr) gate_desc s; pack_gate(&s, GATE_INTERRUPT, (unsigned long)addr, 0, 0, __KERNEL_CS); - write_idt_entry(nmi_idt_table, gate, &s); + write_idt_entry(debug_idt_table, gate, &s); } #endif @@ -405,4 +405,45 @@ static inline void set_system_intr_gate_ist(int n, void *addr, unsigned ist) _set_gate(n, GATE_INTERRUPT, addr, 0x3, ist, __KERNEL_CS); } +#ifdef CONFIG_X86_64 +DECLARE_PER_CPU(u32, debug_idt_ctr); +static inline bool is_debug_idt_enabled(void) +{ + if (this_cpu_read(debug_idt_ctr)) + return true; + + return false; +} + +static inline void load_debug_idt(void) +{ + load_idt((const struct desc_ptr *)&debug_idt_descr); +} +#else +static inline bool is_debug_idt_enabled(void) +{ + return false; +} + +static inline void load_debug_idt(void) +{ +} +#endif + +/* + * the load_current_idt() is called with interrupt disabled by local_irq_save() + * to avoid races. That way the IDT will always be set back to the expected + * descriptor. + */ +static inline void load_current_idt(void) +{ + unsigned long flags; + + local_irq_save(flags); + if (is_debug_idt_enabled()) + load_debug_idt(); + else + load_idt((const struct desc_ptr *)&idt_descr); + local_irq_restore(flags); +} #endif /* _ASM_X86_DESC_H */ |