Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 05161b9c authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar
Browse files

x86/irq: Get rid of the 'first_system_vector' indirection bogosity 



This variable is beyond pointless. Nothing allocates a vector via
alloc_gate() below FIRST_SYSTEM_VECTOR. So nothing can change
first_system_vector.

If there is a need for a gate below FIRST_SYSTEM_VECTOR then it can be
added to the vector defines and FIRST_SYSTEM_VECTOR can be adjusted
accordingly.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
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/20170828064956.357109735@linutronix.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent fa4ab577

arch/x86/include/asm/desc.h

+2 −3
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include <asm/ldt.h>

#include <asm/mmu.h>

#include <asm/fixmap.h>

#include <asm/irq_vectors.h>



#include <linux/smp.h>

#include <linux/percpu.h>
@@ -482,16 +483,14 @@ static inline void _set_gate(int gate, unsigned type, void *addr, 
				0, 0, __KERNEL_CS);			\

	} while (0)



extern int first_system_vector;

/* used_vectors is BITMAP for irq is not managed by percpu vector_irq */

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);

		if (first_system_vector > vector)

			first_system_vector = vector;

	} else {

		BUG();

	}

arch/x86/kernel/apic/apic.c

+0 −2
Original line number Diff line number Diff line
@@ -177,8 +177,6 @@ static int disable_apic_timer __initdata; 
int local_apic_timer_c2_ok;

EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);



int first_system_vector = FIRST_SYSTEM_VECTOR;



/*

 * Debug level, exported for io_apic.c

 */

arch/x86/kernel/apic/vector.c

+1 −1
Original line number Diff line number Diff line
@@ -166,7 +166,7 @@ static int __assign_irq_vector(int irq, struct apic_chip_data *d, 
		offset = current_offset;

next:

		vector += 16;

		if (vector >= first_system_vector) {

		if (vector >= FIRST_SYSTEM_VECTOR) {

			offset = (offset + 1) % 16;

			vector = FIRST_EXTERNAL_VECTOR + offset;

		}

arch/x86/kernel/irq.c

+1 −1
Original line number Diff line number Diff line
@@ -429,7 +429,7 @@ int check_irq_vectors_for_cpu_disable(void) 
		 * this w/o holding vector_lock.

		 */

		for (vector = FIRST_EXTERNAL_VECTOR;

		     vector < first_system_vector; vector++) {

		     vector < FIRST_SYSTEM_VECTOR; vector++) {

			if (!test_bit(vector, used_vectors) &&

			    IS_ERR_OR_NULL(per_cpu(vector_irq, cpu)[vector])) {

				if (++count == this_count)

arch/x86/kernel/irqinit.c

+1 −4
Original line number Diff line number Diff line
@@ -169,10 +169,7 @@ void __init native_init_IRQ(void) 
	 * 'special' SMP interrupts)

	 */

	i = FIRST_EXTERNAL_VECTOR;

#ifndef CONFIG_X86_LOCAL_APIC

#define first_system_vector NR_VECTORS

#endif

	for_each_clear_bit_from(i, used_vectors, first_system_vector) {

	for_each_clear_bit_from(i, used_vectors, FIRST_SYSTEM_VECTOR) {

		/* IA32_SYSCALL_VECTOR could be used in trap_init already. */

		set_intr_gate(i, irq_entries_start +

				8 * (i - FIRST_EXTERNAL_VECTOR));