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

Commit 12e189d3 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

x86/x2apic: Add proper state tracking 



Having 3 different variables to track the state is just silly and
error prone. Add a proper state tracking variable which covers the
three possible states: ON/OFF/DISABLED.

We cannot use x2apic_mode for this as this would require to change all
users of x2apic_mode with explicit comparisons for a state value
instead of treating it as boolean.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarBorislav Petkov <bp@alien8.de>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20150115211702.955392443@linutronix.de


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 62e61633

arch/x86/kernel/apic/apic.c

+14 −1
Original line number Diff line number Diff line
@@ -1480,6 +1480,14 @@ static bool nox2apic __initdata; 
#ifdef CONFIG_X86_X2APIC

int x2apic_mode;

static int x2apic_disabled;



enum {

	X2APIC_OFF,

	X2APIC_ON,

	X2APIC_DISABLED,

};

static int x2apic_state;



static int __init setup_nox2apic(char *str)

{

	if (x2apic_enabled()) {
@@ -1496,7 +1504,7 @@ static int __init setup_nox2apic(char *str) 
		setup_clear_cpu_cap(X86_FEATURE_X2APIC);



	nox2apic = true;



	x2apic_state = X2APIC_DISABLED;

	return 0;

}

early_param("nox2apic", setup_nox2apic);
@@ -1539,6 +1547,7 @@ static __init void disable_x2apic(void) 
	}



	x2apic_disabled = 1;

	x2apic_state = X2APIC_DISABLED;

}



void enable_x2apic(void)
@@ -1559,6 +1568,7 @@ void enable_x2apic(void) 
		printk_once(KERN_INFO "Enabling x2apic\n");

		wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);

	}

	x2apic_state = X2APIC_ON;

}



static __init void try_to_enable_x2apic(int remap_mode)
@@ -1597,6 +1607,9 @@ void __init check_x2apic(void) 
	if (x2apic_enabled()) {

		pr_info("x2apic: enabled by BIOS, switching to x2apic ops\n");

		x2apic_mode = 1;

		x2apic_state = X2APIC_ON;

	} else if (!cpu_has_x2apic) {

		x2apic_state = X2APIC_DISABLED;

	}

}

#else /* CONFIG_X86_X2APIC */