linux-kernel-test/arch/x86/kernel/apic/probe_64.c
Suresh Siddha 681ee44d40 x86, apic: Don't use logical-flat mode when CPU hotplug may exceed 8 CPUs
We need to fall back from logical-flat APIC mode to physical-flat mode
when we have more than 8 CPUs.  However, in the presence of CPU
hotplug(with bios listing not enabled but possible cpus as disabled cpus in
MADT), we have to consider the number of possible CPUs rather than
the number of current CPUs; otherwise we may cross the 8-CPU boundary
when CPUs are added later.

32bit apic code can use more cleanups (like the removal of vendor checks in
32bit default_setup_apic_routing()) and more unifications with 64bit code.
Yinghai has some patches in works already. This patch addresses the boot issue
that is reported in the virtualization guest context.

[ hpa: incorporated function annotation feedback from Yinghai Lu ]

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1265767304.2833.19.camel@sbs-t61.sc.intel.com>
Acked-by: Shaohui Zheng <shaohui.zheng@intel.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-09 20:51:11 -08:00

109 lines
2.3 KiB
C

/*
* Copyright 2004 James Cleverdon, IBM.
* Subject to the GNU Public License, v.2
*
* Generic APIC sub-arch probe layer.
*
* Hacked for x86-64 by James Cleverdon from i386 architecture code by
* Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
* James Cleverdon.
*/
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/hardirq.h>
#include <linux/dmar.h>
#include <asm/smp.h>
#include <asm/apic.h>
#include <asm/ipi.h>
#include <asm/setup.h>
extern struct apic apic_flat;
extern struct apic apic_physflat;
extern struct apic apic_x2xpic_uv_x;
extern struct apic apic_x2apic_phys;
extern struct apic apic_x2apic_cluster;
struct apic __read_mostly *apic = &apic_flat;
EXPORT_SYMBOL_GPL(apic);
static struct apic *apic_probe[] __initdata = {
#ifdef CONFIG_X86_UV
&apic_x2apic_uv_x,
#endif
#ifdef CONFIG_X86_X2APIC
&apic_x2apic_phys,
&apic_x2apic_cluster,
#endif
&apic_physflat,
NULL,
};
static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
{
return hard_smp_processor_id() >> index_msb;
}
/*
* Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
*/
void __init default_setup_apic_routing(void)
{
#ifdef CONFIG_X86_X2APIC
if (x2apic_mode
#ifdef CONFIG_X86_UV
&& apic != &apic_x2apic_uv_x
#endif
) {
if (x2apic_phys)
apic = &apic_x2apic_phys;
else
apic = &apic_x2apic_cluster;
}
#endif
if (apic == &apic_flat && num_possible_cpus() > 8)
apic = &apic_physflat;
printk(KERN_INFO "Setting APIC routing to %s\n", apic->name);
if (is_vsmp_box()) {
/* need to update phys_pkg_id */
apic->phys_pkg_id = apicid_phys_pkg_id;
}
/*
* Now that apic routing model is selected, configure the
* fault handling for intr remapping.
*/
if (intr_remapping_enabled)
enable_drhd_fault_handling();
}
/* Same for both flat and physical. */
void apic_send_IPI_self(int vector)
{
__default_send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
}
int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
{
int i;
for (i = 0; apic_probe[i]; ++i) {
if (apic_probe[i]->acpi_madt_oem_check(oem_id, oem_table_id)) {
apic = apic_probe[i];
printk(KERN_INFO "Setting APIC routing to %s.\n",
apic->name);
return 1;
}
}
return 0;
}