diff options
Diffstat (limited to 'arch/x86_64/kernel/genapic.c')
| -rw-r--r-- | arch/x86_64/kernel/genapic.c | 104 |
1 files changed, 19 insertions, 85 deletions
diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c index 0b3603adf56d..47496a40e84f 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) { |
