summaryrefslogtreecommitdiffstats
path: root/arch/x86_64/kernel/genapic.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86_64/kernel/genapic.c')
-rw-r--r--arch/x86_64/kernel/genapic.c104
1 files changed, 19 insertions, 85 deletions
diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c
index 0b3603a..47496a4 100644
--- a/arch/x86_64/kernel/genapic.c
+++ b/arch/x86_64/kernel/genapic.c
@@ -11,120 +11,54 @@
#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/module.h>
#include <asm/smp.h>
#include <asm/ipi.h>
+#include <asm/genapic.h>
-#if defined(CONFIG_ACPI)
+#ifdef CONFIG_ACPI
#include <acpi/acpi_bus.h>
#endif
/* which logical CPU number maps to which CPU (physical APIC ID) */
-u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
+u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly
+ = { [0 ... NR_CPUS-1] = BAD_APICID };
EXPORT_SYMBOL(x86_cpu_to_apicid);
-u8 x86_cpu_to_log_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
-extern struct genapic apic_cluster;
-extern struct genapic apic_flat;
-extern struct genapic apic_physflat;
+u8 x86_cpu_to_log_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
-struct genapic *genapic = &apic_flat;
-struct genapic *genapic_force;
+struct genapic __read_mostly *genapic = &apic_flat;
/*
* Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
*/
-void __init clustered_apic_check(void)
+void __init setup_apic_routing(void)
{
- long i;
- u8 clusters, max_cluster;
- u8 id;
- u8 cluster_cnt[NUM_APIC_CLUSTERS];
- int max_apic = 0;
-
- /* genapic selection can be forced because of certain quirks.
- */
- if (genapic_force) {
- genapic = genapic_force;
- goto print;
- }
-
-#if defined(CONFIG_ACPI)
+#ifdef CONFIG_ACPI
/*
- * Some x86_64 machines use physical APIC mode regardless of how many
- * procs/clusters are present (x86_64 ES7000 is an example).
+ * Quirk: some x86_64 machines can only use physical APIC mode
+ * regardless of how many processors are present (x86_64 ES7000
+ * is an example).
*/
- if (acpi_gbl_FADT.header.revision > FADT2_REVISION_ID)
- if (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL) {
- genapic = &apic_cluster;
- goto print;
- }
-#endif
-
- memset(cluster_cnt, 0, sizeof(cluster_cnt));
- for (i = 0; i < NR_CPUS; i++) {
- id = bios_cpu_apicid[i];
- if (id == BAD_APICID)
- continue;
- if (id > max_apic)
- max_apic = id;
- cluster_cnt[APIC_CLUSTERID(id)]++;
- }
-
- /* Don't use clustered mode on AMD platforms. */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+ if (acpi_gbl_FADT.header.revision > FADT2_REVISION_ID &&
+ (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL))
genapic = &apic_physflat;
-#ifndef CONFIG_HOTPLUG_CPU
- /* In the CPU hotplug case we cannot use broadcast mode
- because that opens a race when a CPU is removed.
- Stay at physflat mode in this case.
- It is bad to do this unconditionally though. Once
- we have ACPI platform support for CPU hotplug
- we should detect hotplug capablity from ACPI tables and
- only do this when really needed. -AK */
- if (max_apic <= 8)
- genapic = &apic_flat;
+ else
#endif
- goto print;
- }
- clusters = 0;
- max_cluster = 0;
-
- for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
- if (cluster_cnt[i] > 0) {
- ++clusters;
- if (cluster_cnt[i] > max_cluster)
- max_cluster = cluster_cnt[i];
- }
- }
-
- /*
- * If we have clusters <= 1 and CPUs <= 8 in cluster 0, then flat mode,
- * else if max_cluster <= 4 and cluster_cnt[15] == 0, clustered logical
- * else physical mode.
- * (We don't use lowest priority delivery + HW APIC IRQ steering, so
- * can ignore the clustered logical case and go straight to physical.)
- */
- if (clusters <= 1 && max_cluster <= 8 && cluster_cnt[0] == max_cluster) {
-#ifdef CONFIG_HOTPLUG_CPU
- /* Don't use APIC shortcuts in CPU hotplug to avoid races */
- genapic = &apic_physflat;
-#else
+ if (cpus_weight(cpu_possible_map) <= 8)
genapic = &apic_flat;
-#endif
- } else
- genapic = &apic_cluster;
+ else
+ genapic = &apic_physflat;
-print:
printk(KERN_INFO "Setting APIC routing to %s\n", genapic->name);
}
-/* Same for both flat and clustered. */
+/* Same for both flat and physical. */
void send_IPI_self(int vector)
{
OpenPOWER on IntegriCloud