arch/x86/kernel/apic/apic.c

Source file repositories/reference/linux-study-clean/arch/x86/kernel/apic/apic.c

File Facts

System
Linux kernel
Corpus path
arch/x86/kernel/apic/apic.c
Extension
.c
Size
68311 bytes
Lines
2701
Domain
Architecture Layer
Bucket
arch/x86
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

core_initcall(init_lapic_sysfs);

#else	/* CONFIG_PM */

static void apic_pm_activate(void) { }

#endif	/* CONFIG_PM */

#ifdef CONFIG_X86_64

static int multi_checked;
static int multi;

static int set_multi(const struct dmi_system_id *d)
{
	if (multi)
		return 0;
	pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
	multi = 1;
	return 0;
}

static const struct dmi_system_id multi_dmi_table[] = {
	{
		.callback = set_multi,
		.ident = "IBM System Summit2",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
			DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
		},
	},
	{}
};

static void dmi_check_multi(void)
{
	if (multi_checked)
		return;

	dmi_check_system(multi_dmi_table);
	multi_checked = 1;
}

/*
 * apic_is_clustered_box() -- Check if we can expect good TSC
 *
 * Thus far, the major user of this is IBM's Summit2 series:
 * Clustered boxes may have unsynced TSC problems if they are
 * multi-chassis.
 * Use DMI to check them
 */
int apic_is_clustered_box(void)
{
	dmi_check_multi();
	return multi;
}
#endif

/*
 * APIC command line parameters
 */
static int __init setup_nolapic(char *arg)
{
	apic_is_disabled = true;
	setup_clear_cpu_cap(X86_FEATURE_APIC);
	return 0;
}
early_param("nolapic", setup_nolapic);

static int __init parse_lapic_timer_c2_ok(char *arg)
{
	local_apic_timer_c2_ok = 1;
	return 0;
}
early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);

static int __init parse_disable_apic_timer(char *arg)
{
	disable_apic_timer = 1;
	return 0;
}
early_param("noapictimer", parse_disable_apic_timer);

static int __init parse_nolapic_timer(char *arg)
{
	disable_apic_timer = 1;
	return 0;
}
early_param("nolapic_timer", parse_nolapic_timer);

Annotation

Implementation Notes