From 635186447d0e6f3b35895fda993a266a1315d2a7 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sat, 16 Apr 2005 15:25:16 -0700 Subject: [PATCH] x86_64: Final support for AMD dual core Clean up the code greatly. Now uses the infrastructure from the Intel dual core patch Should fix a final bug noticed by Tyan of not detecting the nodes correctly in some corner cases. Patch for x86-64 and i386 Signed-off-by: Andi Kleen Signed-off-by: Rafael J. Wysocki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/cpu/amd.c | 24 ++++++++++++++---------- arch/i386/kernel/cpu/common.c | 2 +- 2 files changed, 15 insertions(+), 11 deletions(-) (limited to 'arch/i386') diff --git a/arch/i386/kernel/cpu/amd.c b/arch/i386/kernel/cpu/amd.c index fa10d0a509c7..8d182e875cd7 100644 --- a/arch/i386/kernel/cpu/amd.c +++ b/arch/i386/kernel/cpu/amd.c @@ -24,6 +24,9 @@ __asm__(".align 4\nvide: ret"); static void __init init_amd(struct cpuinfo_x86 *c) { +#ifdef CONFIG_SMP + int cpu = c == &boot_cpu_data ? 0 : c - cpu_data; +#endif u32 l, h; int mbytes = num_physpages >> (20-PAGE_SHIFT); int r; @@ -195,16 +198,17 @@ static void __init init_amd(struct cpuinfo_x86 *c) c->x86_num_cores = 1; } - detect_ht(c); - -#ifdef CONFIG_X86_HT - /* AMD dual core looks like HT but isn't really. Hide it from the - scheduler. This works around problems with the domain scheduler. - Also probably gives slightly better scheduling and disables - SMT nice which is harmful on dual core. - TBD tune the domain scheduler for dual core. */ - if (cpu_has(c, X86_FEATURE_CMP_LEGACY)) - smp_num_siblings = 1; +#ifdef CONFIG_SMP + /* + * On a AMD dual core setup the lower bits of the APIC id + * distingush the cores. Assumes number of cores is a power + * of two. + */ + if (c->x86_num_cores > 1) { + cpu_core_id[cpu] = cpu >> hweight32(c->x86_num_cores - 1); + printk(KERN_INFO "CPU %d(%d) -> Core %d\n", + cpu, c->x86_num_cores, cpu_core_id[cpu]); + } #endif } diff --git a/arch/i386/kernel/cpu/common.c b/arch/i386/kernel/cpu/common.c index ed4c9c3fe667..6be0310e3cd3 100644 --- a/arch/i386/kernel/cpu/common.c +++ b/arch/i386/kernel/cpu/common.c @@ -437,7 +437,7 @@ void __init detect_ht(struct cpuinfo_x86 *c) int index_msb, tmp; int cpu = smp_processor_id(); - if (!cpu_has(c, X86_FEATURE_HT)) + if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY)) return; cpuid(1, &eax, &ebx, &ecx, &edx); -- cgit v1.2.3-59-g8ed1b