Commit 7443b296 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Peter Zijlstra
Browse files

x86/percpu: Move cpu_number next to current_task 



Also add cpu_number to the pcpu_hot structure, it is often referenced
and this cacheline is there.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111145.387678283@infradead.org
parent 64701838

arch/x86/include/asm/current.h

+1 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ struct pcpu_hot { 
		struct {

			struct task_struct	*current_task;

			int			preempt_count;

			int			cpu_number;

		};

		u8	pad[64];

	};

arch/x86/include/asm/smp.h

+5 −7
Original line number Diff line number Diff line
@@ -3,10 +3,10 @@ 
#define _ASM_X86_SMP_H

#ifndef __ASSEMBLY__

#include <linux/cpumask.h>

#include <asm/percpu.h>



#include <asm/thread_info.h>

#include <asm/cpumask.h>

#include <asm/current.h>

#include <asm/thread_info.h>



extern int smp_num_siblings;

extern unsigned int num_processors;
@@ -19,7 +19,6 @@ DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); 
DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_l2c_shared_map);

DECLARE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id);

DECLARE_PER_CPU_READ_MOSTLY(u16, cpu_l2c_id);

DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number);



DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid);

DECLARE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid);
@@ -150,11 +149,10 @@ __visible void smp_call_function_single_interrupt(struct pt_regs *r); 


/*

 * This function is needed by all SMP systems. It must _always_ be valid

 * from the initial startup. We map APIC_BASE very early in page_setup(),

 * so this is correct in the x86 case.

 * from the initial startup.

 */

#define raw_smp_processor_id()  this_cpu_read(cpu_number)

#define __smp_processor_id() __this_cpu_read(cpu_number)

#define raw_smp_processor_id()  this_cpu_read(pcpu_hot.cpu_number)

#define __smp_processor_id() __this_cpu_read(pcpu_hot.cpu_number)



#ifdef CONFIG_X86_32

extern int safe_smp_processor_id(void);

arch/x86/kernel/setup_percpu.c

+1 −4
Original line number Diff line number Diff line
@@ -23,9 +23,6 @@ 
#include <asm/cpu.h>

#include <asm/stackprotector.h>



DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number);

EXPORT_PER_CPU_SYMBOL(cpu_number);



#ifdef CONFIG_X86_64

#define BOOT_PERCPU_OFFSET ((unsigned long)__per_cpu_load)

#else
@@ -172,7 +169,7 @@ void __init setup_per_cpu_areas(void) 
	for_each_possible_cpu(cpu) {

		per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu];

		per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu);

		per_cpu(cpu_number, cpu) = cpu;

		per_cpu(pcpu_hot.cpu_number, cpu) = cpu;

		setup_percpu_segment(cpu);

		/*

		 * Copy data used in early init routines from the