From 94605eff572b727aaad9b4b29bc358b919096503 Mon Sep 17 00:00:00 2001 From: "Siddha, Suresh B" Date: Sat, 5 Nov 2005 17:25:54 +0100 Subject: [PATCH] x86-64/i386: Intel HT, Multi core detection fixes Fields obtained through cpuid vector 0x1(ebx[16:23]) and vector 0x4(eax[14:25], eax[26:31]) indicate the maximum values and might not always be the same as what is available and what OS sees. So make sure "siblings" and "cpu cores" values in /proc/cpuinfo reflect the values as seen by OS instead of what cpuid instruction says. This will also fix the buggy BIOS cases (for example where cpuid on a single core cpu says there are "2" siblings, even when HT is disabled in the BIOS. http://bugzilla.kernel.org/show_bug.cgi?id=4359) Signed-off-by: Suresh Siddha Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- arch/i386/kernel/smpboot.c | 73 +++++++++++++++++++++++++++++++++------------- 1 file changed, 53 insertions(+), 20 deletions(-) (limited to 'arch/i386/kernel/smpboot.c') diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c index 01b618e73ec..0a9c6465523 100644 --- a/arch/i386/kernel/smpboot.c +++ b/arch/i386/kernel/smpboot.c @@ -74,9 +74,11 @@ EXPORT_SYMBOL(phys_proc_id); int cpu_core_id[NR_CPUS] __read_mostly = {[0 ... NR_CPUS-1] = BAD_APICID}; EXPORT_SYMBOL(cpu_core_id); +/* representing HT siblings of each logical CPU */ cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly; EXPORT_SYMBOL(cpu_sibling_map); +/* representing HT and core siblings of each logical CPU */ cpumask_t cpu_core_map[NR_CPUS] __read_mostly; EXPORT_SYMBOL(cpu_core_map); @@ -444,35 +446,60 @@ static void __devinit smp_callin(void) static int cpucount; +/* representing cpus for which sibling maps can be computed */ +static cpumask_t cpu_sibling_setup_map; + static inline void set_cpu_sibling_map(int cpu) { int i; + struct cpuinfo_x86 *c = cpu_data; + + cpu_set(cpu, cpu_sibling_setup_map); if (smp_num_siblings > 1) { - for (i = 0; i < NR_CPUS; i++) { - if (!cpu_isset(i, cpu_callout_map)) - continue; - if (cpu_core_id[cpu] == cpu_core_id[i]) { + for_each_cpu_mask(i, cpu_sibling_setup_map) { + if (phys_proc_id[cpu] == phys_proc_id[i] && + cpu_core_id[cpu] == cpu_core_id[i]) { cpu_set(i, cpu_sibling_map[cpu]); cpu_set(cpu, cpu_sibling_map[i]); + cpu_set(i, cpu_core_map[cpu]); + cpu_set(cpu, cpu_core_map[i]); } } } else { cpu_set(cpu, cpu_sibling_map[cpu]); } - if (current_cpu_data.x86_num_cores > 1) { - for (i = 0; i < NR_CPUS; i++) { - if (!cpu_isset(i, cpu_callout_map)) - continue; - if (phys_proc_id[cpu] == phys_proc_id[i]) { - cpu_set(i, cpu_core_map[cpu]); - cpu_set(cpu, cpu_core_map[i]); - } - } - } else { + if (current_cpu_data.x86_max_cores == 1) { cpu_core_map[cpu] = cpu_sibling_map[cpu]; + c[cpu].booted_cores = 1; + return; + } + + for_each_cpu_mask(i, cpu_sibling_setup_map) { + if (phys_proc_id[cpu] == phys_proc_id[i]) { + cpu_set(i, cpu_core_map[cpu]); + cpu_set(cpu, cpu_core_map[i]); + /* + * Does this new cpu bringup a new core? + */ + if (cpus_weight(cpu_sibling_map[cpu]) == 1) { + /* + * for each core in package, increment + * the booted_cores for this new cpu + */ + if (first_cpu(cpu_sibling_map[i]) == i) + c[cpu].booted_cores++; + /* + * increment the core count for all + * the other cpus in this package + */ + if (i != cpu) + c[i].booted_cores++; + } else if (i != cpu && !c[cpu].booted_cores) + c[cpu].booted_cores = c[i].booted_cores; + } } } @@ -1096,11 +1123,8 @@ static void __init smp_boot_cpus(unsigned int max_cpus) current_thread_info()->cpu = 0; smp_tune_scheduling(); - cpus_clear(cpu_sibling_map[0]); - cpu_set(0, cpu_sibling_map[0]); - cpus_clear(cpu_core_map[0]); - cpu_set(0, cpu_core_map[0]); + set_cpu_sibling_map(0); /* * If we couldn't find an SMP configuration at boot time, @@ -1279,15 +1303,24 @@ static void remove_siblinginfo(int cpu) { int sibling; + struct cpuinfo_x86 *c = cpu_data; + for_each_cpu_mask(sibling, cpu_core_map[cpu]) { + cpu_clear(cpu, cpu_core_map[sibling]); + /* + * last thread sibling in this cpu core going down + */ + if (cpus_weight(cpu_sibling_map[cpu]) == 1) + c[sibling].booted_cores--; + } + for_each_cpu_mask(sibling, cpu_sibling_map[cpu]) cpu_clear(cpu, cpu_sibling_map[sibling]); - for_each_cpu_mask(sibling, cpu_core_map[cpu]) - cpu_clear(cpu, cpu_core_map[sibling]); cpus_clear(cpu_sibling_map[cpu]); cpus_clear(cpu_core_map[cpu]); phys_proc_id[cpu] = BAD_APICID; cpu_core_id[cpu] = BAD_APICID; + cpu_clear(cpu, cpu_sibling_setup_map); } int __cpu_disable(void) -- cgit v1.2.3