diff options
Diffstat (limited to 'arch/x86_64/kernel/genapic.c')
| -rw-r--r-- | arch/x86_64/kernel/genapic.c | 71 |
1 files changed, 15 insertions, 56 deletions
diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c index 2f2b8fc6e2f3..025f26ebb8d7 100644 --- a/arch/x86_64/kernel/genapic.c +++ b/arch/x86_64/kernel/genapic.c @@ -11,26 +11,24 @@ #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> -#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 __read_mostly *genapic = &apic_flat; @@ -39,76 +37,37 @@ struct genapic __read_mostly *genapic = &apic_flat; */ void __init clustered_apic_check(void) { - int i; - u8 clusters, max_cluster; + unsigned int i, max_apic = 0; u8 id; - u8 cluster_cnt[NUM_APIC_CLUSTERS]; - int max_apic = 0; #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; - } + if (acpi_gbl_FADT.header.revision > FADT2_REVISION_ID && + (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) + genapic = &apic_physflat; #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, default - * to flat logical mode. - */ - if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) { - /* - * Switch to physical flat mode if more than 8 APICs - * (In the case of 8 CPUs APIC ID goes from 0 to 7): - */ - if (max_apic >= 8) - genapic = &apic_physflat; - 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) + if (max_apic < 8) genapic = &apic_flat; else - genapic = &apic_cluster; + 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) { |