[Patch 1/2] x86, x86_64: Intel HT, Multi core detection fixes
From: Siddha, Suresh B
Date: Wed Oct 12 2005 - 16:37:24 EST
Andrew, Please apply.
thanks,
suresh
--
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 <suresh.b.siddha@xxxxxxxxx>
diff -pNru linux-2.6.14-rc4/arch/i386/kernel/cpu/common.c linux-2.6.14-rc4-dc/arch/i386/kernel/cpu/common.c
--- linux-2.6.14-rc4/arch/i386/kernel/cpu/common.c 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/arch/i386/kernel/cpu/common.c 2005-10-12 11:02:00.361726016 -0700
@@ -446,32 +446,29 @@ void __devinit identify_cpu(struct cpuin
void __devinit detect_ht(struct cpuinfo_x86 *c)
{
u32 eax, ebx, ecx, edx;
- int index_msb, tmp;
+ int index_msb, core_bits;
int cpu = smp_processor_id();
+ cpuid(1, &eax, &ebx, &ecx, &edx);
+
+ c->apicid = phys_pkg_id((ebx >> 24) & 0xFF, 0);
+
if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY))
return;
- cpuid(1, &eax, &ebx, &ecx, &edx);
smp_num_siblings = (ebx & 0xff0000) >> 16;
if (smp_num_siblings == 1) {
printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
} else if (smp_num_siblings > 1 ) {
- index_msb = 31;
if (smp_num_siblings > NR_CPUS) {
printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
smp_num_siblings = 1;
return;
}
- tmp = smp_num_siblings;
- while ((tmp & 0x80000000 ) == 0) {
- tmp <<=1 ;
- index_msb--;
- }
- if (smp_num_siblings & (smp_num_siblings - 1))
- index_msb++;
+
+ index_msb = get_count_order(smp_num_siblings);
phys_proc_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
@@ -479,17 +476,12 @@ void __devinit detect_ht(struct cpuinfo_
smp_num_siblings = smp_num_siblings / c->x86_num_cores;
- tmp = smp_num_siblings;
- index_msb = 31;
- while ((tmp & 0x80000000) == 0) {
- tmp <<=1 ;
- index_msb--;
- }
+ index_msb = get_count_order(smp_num_siblings) ;
- if (smp_num_siblings & (smp_num_siblings - 1))
- index_msb++;
+ core_bits = get_count_order(c->x86_num_cores);
- cpu_core_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
+ cpu_core_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb) &
+ ((1 << core_bits) - 1);
if (c->x86_num_cores > 1)
printk(KERN_INFO "CPU: Processor Core ID: %d\n",
diff -pNru linux-2.6.14-rc4/arch/i386/kernel/cpu/proc.c linux-2.6.14-rc4-dc/arch/i386/kernel/cpu/proc.c
--- linux-2.6.14-rc4/arch/i386/kernel/cpu/proc.c 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/arch/i386/kernel/cpu/proc.c 2005-10-12 11:03:05.211867296 -0700
@@ -96,10 +96,9 @@ static int show_cpuinfo(struct seq_file
#ifdef CONFIG_X86_HT
if (c->x86_num_cores * smp_num_siblings > 1) {
seq_printf(m, "physical id\t: %d\n", phys_proc_id[n]);
- seq_printf(m, "siblings\t: %d\n",
- c->x86_num_cores * smp_num_siblings);
+ seq_printf(m, "siblings\t: %d\n", cpus_weight(cpu_core_map[n]));
seq_printf(m, "core id\t\t: %d\n", cpu_core_id[n]);
- seq_printf(m, "cpu cores\t: %d\n", c->x86_num_cores);
+ seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
}
#endif
diff -pNru linux-2.6.14-rc4/arch/i386/kernel/smpboot.c linux-2.6.14-rc4-dc/arch/i386/kernel/smpboot.c
--- linux-2.6.14-rc4/arch/i386/kernel/smpboot.c 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/arch/i386/kernel/smpboot.c 2005-10-12 11:12:53.383451624 -0700
@@ -440,35 +440,59 @@ static void __devinit smp_callin(void)
static int cpucount;
+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_num_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;
+ }
}
}
@@ -1092,11 +1116,8 @@ static void __init smp_boot_cpus(unsigne
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,
@@ -1275,15 +1296,24 @@ 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)
diff -pNru linux-2.6.14-rc4/arch/x86_64/kernel/setup.c linux-2.6.14-rc4-dc/arch/x86_64/kernel/setup.c
--- linux-2.6.14-rc4/arch/x86_64/kernel/setup.c 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/arch/x86_64/kernel/setup.c 2005-10-12 11:29:43.188937856 -0700
@@ -889,52 +889,42 @@ static void __cpuinit detect_ht(struct c
{
#ifdef CONFIG_SMP
u32 eax, ebx, ecx, edx;
- int index_msb, tmp;
+ int index_msb, core_bits;
int cpu = smp_processor_id();
-
+
+ cpuid(1, &eax, &ebx, &ecx, &edx);
+
+ c->apicid = phys_pkg_id(0);
+
if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY))
return;
- cpuid(1, &eax, &ebx, &ecx, &edx);
smp_num_siblings = (ebx & 0xff0000) >> 16;
-
+
if (smp_num_siblings == 1) {
printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
- } else if (smp_num_siblings > 1) {
- index_msb = 31;
- /*
- * At this point we only support two siblings per
- * processor package.
- */
+ } else if (smp_num_siblings > 1 ) {
+
if (smp_num_siblings > NR_CPUS) {
printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
smp_num_siblings = 1;
return;
}
- tmp = smp_num_siblings;
- while ((tmp & 0x80000000 ) == 0) {
- tmp <<=1 ;
- index_msb--;
- }
- if (smp_num_siblings & (smp_num_siblings - 1))
- index_msb++;
+
+ index_msb = get_count_order(smp_num_siblings);
phys_proc_id[cpu] = phys_pkg_id(index_msb);
-
+
printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
phys_proc_id[cpu]);
smp_num_siblings = smp_num_siblings / c->x86_num_cores;
- tmp = smp_num_siblings;
- index_msb = 31;
- while ((tmp & 0x80000000) == 0) {
- tmp <<=1 ;
- index_msb--;
- }
- if (smp_num_siblings & (smp_num_siblings - 1))
- index_msb++;
+ index_msb = get_count_order(smp_num_siblings) ;
+
+ core_bits = get_count_order(c->x86_num_cores);
- cpu_core_id[cpu] = phys_pkg_id(index_msb);
+ cpu_core_id[cpu] = phys_pkg_id(index_msb) &
+ ((1 << core_bits) - 1);
if (c->x86_num_cores > 1)
printk(KERN_INFO "CPU: Processor Core ID: %d\n",
@@ -1274,10 +1264,9 @@ static int show_cpuinfo(struct seq_file
if (smp_num_siblings * c->x86_num_cores > 1) {
int cpu = c - cpu_data;
seq_printf(m, "physical id\t: %d\n", phys_proc_id[cpu]);
- seq_printf(m, "siblings\t: %d\n",
- c->x86_num_cores * smp_num_siblings);
+ seq_printf(m, "siblings\t: %d\n", cpus_weight(cpu_core_map[cpu]));
seq_printf(m, "core id\t\t: %d\n", cpu_core_id[cpu]);
- seq_printf(m, "cpu cores\t: %d\n", c->x86_num_cores);
+ seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
}
#endif
diff -pNru linux-2.6.14-rc4/arch/x86_64/kernel/smpboot.c linux-2.6.14-rc4-dc/arch/x86_64/kernel/smpboot.c
--- linux-2.6.14-rc4/arch/x86_64/kernel/smpboot.c 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/arch/x86_64/kernel/smpboot.c 2005-10-12 11:17:34.109774736 -0700
@@ -436,30 +436,58 @@ void __cpuinit smp_callin(void)
cpu_set(cpuid, cpu_callin_map);
}
+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_each_cpu(i) {
- 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_each_cpu(i) {
- 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_num_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;
+ }
}
}
@@ -966,6 +994,7 @@ void __init smp_prepare_cpus(unsigned in
nmi_watchdog_default();
current_cpu_data = boot_cpu_data;
current_thread_info()->cpu = 0; /* needed? */
+ set_cpu_sibling_map(0);
if (smp_sanity_check(max_cpus) < 0) {
printk(KERN_INFO "SMP disabled\n");
@@ -1009,8 +1038,6 @@ void __init smp_prepare_boot_cpu(void)
int me = smp_processor_id();
cpu_set(me, cpu_online_map);
cpu_set(me, cpu_callout_map);
- cpu_set(0, cpu_sibling_map[0]);
- cpu_set(0, cpu_core_map[0]);
per_cpu(cpu_state, me) = CPU_ONLINE;
}
@@ -1082,15 +1109,24 @@ void __init smp_cpus_done(unsigned int m
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);
}
void remove_cpu_from_maps(void)
diff -pNru linux-2.6.14-rc4/include/asm-i386/processor.h linux-2.6.14-rc4-dc/include/asm-i386/processor.h
--- linux-2.6.14-rc4/include/asm-i386/processor.h 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/include/asm-i386/processor.h 2005-10-12 10:59:34.927835328 -0700
@@ -66,6 +66,8 @@ struct cpuinfo_x86 {
int coma_bug;
unsigned long loops_per_jiffy;
unsigned char x86_num_cores;
+ unsigned char booted_cores;
+ unsigned char apicid;
} __attribute__((__aligned__(SMP_CACHE_BYTES)));
#define X86_VENDOR_INTEL 0
diff -pNru linux-2.6.14-rc4/include/asm-x86_64/processor.h linux-2.6.14-rc4-dc/include/asm-x86_64/processor.h
--- linux-2.6.14-rc4/include/asm-x86_64/processor.h 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/include/asm-x86_64/processor.h 2005-10-12 10:44:45.467053920 -0700
@@ -65,6 +65,8 @@ struct cpuinfo_x86 {
__u32 x86_power;
__u32 extended_cpuid_level; /* Max extended CPUID function supported */
unsigned long loops_per_jiffy;
+ __u8 apicid;
+ __u8 booted_cores;
} ____cacheline_aligned;
#define X86_VENDOR_INTEL 0
diff -pNru linux-2.6.14-rc4/include/linux/bitops.h linux-2.6.14-rc4-dc/include/linux/bitops.h
--- linux-2.6.14-rc4/include/linux/bitops.h 2005-10-10 18:19:19.000000000 -0700
+++ linux-2.6.14-rc4-dc/include/linux/bitops.h 2005-10-12 11:17:52.585965928 -0700
@@ -84,6 +84,16 @@ static __inline__ int get_bitmask_order(
return order; /* We could be slightly more clever with -1 here... */
}
+static __inline__ int get_count_order(unsigned int count)
+{
+ int order;
+
+ order = fls(count) - 1;
+ if (count & (count - 1))
+ order++;
+ return order;
+}
+
/*
* hweightN: returns the hamming weight (i.e. the number
* of bits set) of a N-bit word
-
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