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Diffstat (limited to 'linux-2.6-xen-sparse/arch/x86_64/kernel/genapic-xen.c')
-rw-r--r--linux-2.6-xen-sparse/arch/x86_64/kernel/genapic-xen.c49
1 files changed, 35 insertions, 14 deletions
diff --git a/linux-2.6-xen-sparse/arch/x86_64/kernel/genapic-xen.c b/linux-2.6-xen-sparse/arch/x86_64/kernel/genapic-xen.c
index e2e4136bc2..1903a5c3e9 100644
--- a/linux-2.6-xen-sparse/arch/x86_64/kernel/genapic-xen.c
+++ b/linux-2.6-xen-sparse/arch/x86_64/kernel/genapic-xen.c
@@ -20,17 +20,18 @@
#include <asm/smp.h>
#include <asm/ipi.h>
-#if defined(CONFIG_ACPI_BUS)
+#if defined(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] = { [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;
#ifndef CONFIG_XEN
struct genapic *genapic = &apic_flat;
@@ -50,14 +51,9 @@ void __init clustered_apic_check(void)
u8 clusters, max_cluster;
u8 id;
u8 cluster_cnt[NUM_APIC_CLUSTERS];
+ int max_apic = 0;
- if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
- /* AMD always uses flat mode right now */
- genapic = &apic_flat;
- goto print;
- }
-
-#if defined(CONFIG_ACPI_BUS)
+#if defined(CONFIG_ACPI)
/*
* Some x86_64 machines use physical APIC mode regardless of how many
* procs/clusters are present (x86_64 ES7000 is an example).
@@ -70,15 +66,35 @@ void __init clustered_apic_check(void)
#endif
memset(cluster_cnt, 0, sizeof(cluster_cnt));
-
for (i = 0; i < NR_CPUS; i++) {
id = bios_cpu_apicid[i];
- if (id != BAD_APICID)
- cluster_cnt[APIC_CLUSTERID(id)]++;
+ 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) {
+ 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;
+#endif
+ goto print;
+ }
+
clusters = 0;
max_cluster = 0;
+
for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
if (cluster_cnt[i] > 0) {
++clusters;
@@ -94,9 +110,14 @@ void __init clustered_apic_check(void)
* (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)
+ 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
genapic = &apic_flat;
- else
+#endif
+ } else
genapic = &apic_cluster;
print: