x86/idt: Deinline setup functions

None of this is performance sensitive in any way - so debloat the kernel.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064959.502052875@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/desc.h

@@ -390,44 +390,11 @@ static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit)
 	desc->limit1 = (limit >> 16) & 0xf;
 }
 
-static inline void _set_gate(int gate, unsigned type, const void *addr,
-			     unsigned dpl, unsigned ist, unsigned seg)
-{
-	gate_desc s;
-
-	pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
-	/*
-	 * does not need to be atomic because it is only done once at
-	 * setup time
-	 */
-	write_idt_entry(idt_table, gate, &s);
-}
-
-static inline void set_intr_gate(unsigned int n, const void *addr)
-{
-	BUG_ON(n > 0xFF);
-	_set_gate(n, GATE_INTERRUPT, addr, 0, 0, __KERNEL_CS);
-}
+void set_intr_gate(unsigned int n, const void *addr);
+void alloc_intr_gate(unsigned int n, const void *addr);
 
 extern unsigned long used_vectors[];
 
-static inline void alloc_system_vector(int vector)
-{
-	BUG_ON(vector < FIRST_SYSTEM_VECTOR);
-	if (!test_bit(vector, used_vectors)) {
-		set_bit(vector, used_vectors);
-	} else {
-		BUG();
-	}
-}
-
-#define alloc_intr_gate(n, addr)				\
-	do {							\
-		alloc_system_vector(n);				\
-		set_intr_gate(n, addr);				\
-	} while (0)
-
-
 #ifdef CONFIG_X86_64
 DECLARE_PER_CPU(u32, debug_idt_ctr);
 static inline bool is_debug_idt_enabled(void)

arch/x86/kernel/idt.c

@@ -212,15 +212,16 @@ static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d)
 #endif
 }
 
-static __init void
-idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size)
+static void
+idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size, bool sys)
 {
 	gate_desc desc;
 
 	for (; size > 0; t++, size--) {
 		idt_init_desc(&desc, t);
-		set_bit(t->vector, used_vectors);
 		write_idt_entry(idt, t->vector, &desc);
+		if (sys)
+			set_bit(t->vector, used_vectors);
 	}
 }
 
@@ -233,7 +234,8 @@ idt_setup_from_table(gate_desc *idt, const struct idt_data *t, int size)
  */
 void __init idt_setup_early_traps(void)
 {
-	idt_setup_from_table(idt_table, early_idts, ARRAY_SIZE(early_idts));
+	idt_setup_from_table(idt_table, early_idts, ARRAY_SIZE(early_idts),
+			     true);
 	load_idt(&idt_descr);
 }
 
@@ -242,7 +244,7 @@ void __init idt_setup_early_traps(void)
  */
 void __init idt_setup_traps(void)
 {
-	idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts));
+	idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts), true);
 }
 
 #ifdef CONFIG_X86_64
@@ -259,15 +261,15 @@ void __init idt_setup_traps(void)
 void __init idt_setup_early_pf(void)
 {
 	idt_setup_from_table(idt_table, early_pf_idts,
-			     ARRAY_SIZE(early_pf_idts));
+			     ARRAY_SIZE(early_pf_idts), true);
 }
 
 /**
  * idt_setup_ist_traps - Initialize the idt table with traps using IST
  */
 void __init idt_setup_ist_traps(void)
 {
-	idt_setup_from_table(idt_table, ist_idts, ARRAY_SIZE(ist_idts));
+	idt_setup_from_table(idt_table, ist_idts, ARRAY_SIZE(ist_idts), true);
 }
 
 /**
@@ -277,7 +279,7 @@ void __init idt_setup_debugidt_traps(void)
 {
 	memcpy(&debug_idt_table, &idt_table, IDT_ENTRIES * 16);
 
-	idt_setup_from_table(debug_idt_table, dbg_idts, ARRAY_SIZE(dbg_idts));
+	idt_setup_from_table(debug_idt_table, dbg_idts, ARRAY_SIZE(dbg_idts), false);
 }
 #endif
 
@@ -289,7 +291,7 @@ void __init idt_setup_apic_and_irq_gates(void)
 	int i = FIRST_EXTERNAL_VECTOR;
 	void *entry;
 
-	idt_setup_from_table(idt_table, apic_idts, ARRAY_SIZE(apic_idts));
+	idt_setup_from_table(idt_table, apic_idts, ARRAY_SIZE(apic_idts), true);
 
 	for_each_clear_bit_from(i, used_vectors, FIRST_SYSTEM_VECTOR) {
 		entry = irq_entries_start + 8 * (i - FIRST_EXTERNAL_VECTOR);
@@ -333,3 +335,26 @@ void idt_invalidate(void *addr)
 
 	load_idt(&idt);
 }
+
+void set_intr_gate(unsigned int n, const void *addr)
+{
+	struct idt_data data;
+
+	BUG_ON(n > 0xFF);
+
+	memset(&data, 0, sizeof(data));
+	data.vector	= n;
+	data.addr	= addr;
+	data.segment	= __KERNEL_CS;
+	data.bits.type	= GATE_INTERRUPT;
+	data.bits.p	= 1;
+
+	idt_setup_from_table(idt_table, &data, 1, false);
+}
+
+void alloc_intr_gate(unsigned int n, const void *addr)
+{
+	BUG_ON(test_bit(n, used_vectors) || n < FIRST_SYSTEM_VECTOR);
+	set_bit(n, used_vectors);
+	set_intr_gate(n, addr);
+}