[tip:x86/cleanups] x86: cpu/common.c more cleanups
From: Ingo Molnar
Date: Sat Mar 14 2009 - 04:56:00 EST
Commit-ID: 0f3fa48a7eaf5d1118cfda1650e8c759b2a116e4
Gitweb: http://git.kernel.org/tip/0f3fa48a7eaf5d1118cfda1650e8c759b2a116e4
Author: Ingo Molnar <mingo@xxxxxxx>
AuthorDate: Sat, 14 Mar 2009 08:46:17 +0100
Commit: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Sat, 14 Mar 2009 10:37:34 +0100
x86: cpu/common.c more cleanups
Complete/fix the cleanups of cpu/common.c:
- fix ugly warning due to asm/topology.h -> linux/topology.h change
- standardize the style across the file
- simplify/refactor the code flow where possible
Cc: Jaswinder Singh Rajput <jaswinder@xxxxxxxxxx>
LKML-Reference: <1237009789.4387.2.camel@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
arch/x86/kernel/cpu/common.c | 243 +++++++++++++++++++++++++-----------------
1 files changed, 143 insertions(+), 100 deletions(-)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index cad6878..a9e3791 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1,4 +1,3 @@
-#include <linux/topology.h>
#include <linux/bootmem.h>
#include <linux/linkage.h>
#include <linux/bitops.h>
@@ -18,6 +17,7 @@
#include <asm/hypervisor.h>
#include <asm/processor.h>
#include <asm/sections.h>
+#include <asm/topology.h>
#include <asm/cpumask.h>
#include <asm/pgtable.h>
#include <asm/atomic.h>
@@ -82,45 +82,45 @@ DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
* TLS descriptors are currently at a different place compared to i386.
* Hopefully nobody expects them at a fixed place (Wine?)
*/
- [GDT_ENTRY_KERNEL32_CS] = { { { 0x0000ffff, 0x00cf9b00 } } },
- [GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00af9b00 } } },
- [GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9300 } } },
- [GDT_ENTRY_DEFAULT_USER32_CS] = { { { 0x0000ffff, 0x00cffb00 } } },
- [GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff300 } } },
- [GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00affb00 } } },
+ [GDT_ENTRY_KERNEL32_CS] = { { { 0x0000ffff, 0x00cf9b00 } } },
+ [GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00af9b00 } } },
+ [GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9300 } } },
+ [GDT_ENTRY_DEFAULT_USER32_CS] = { { { 0x0000ffff, 0x00cffb00 } } },
+ [GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff300 } } },
+ [GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00affb00 } } },
#else
- [GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00cf9a00 } } },
- [GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9200 } } },
- [GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00cffa00 } } },
- [GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff200 } } },
+ [GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00cf9a00 } } },
+ [GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9200 } } },
+ [GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00cffa00 } } },
+ [GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff200 } } },
/*
* Segments used for calling PnP BIOS have byte granularity.
* They code segments and data segments have fixed 64k limits,
* the transfer segment sizes are set at run time.
*/
/* 32-bit code */
- [GDT_ENTRY_PNPBIOS_CS32] = { { { 0x0000ffff, 0x00409a00 } } },
+ [GDT_ENTRY_PNPBIOS_CS32] = { { { 0x0000ffff, 0x00409a00 } } },
/* 16-bit code */
- [GDT_ENTRY_PNPBIOS_CS16] = { { { 0x0000ffff, 0x00009a00 } } },
+ [GDT_ENTRY_PNPBIOS_CS16] = { { { 0x0000ffff, 0x00009a00 } } },
/* 16-bit data */
- [GDT_ENTRY_PNPBIOS_DS] = { { { 0x0000ffff, 0x00009200 } } },
+ [GDT_ENTRY_PNPBIOS_DS] = { { { 0x0000ffff, 0x00009200 } } },
/* 16-bit data */
- [GDT_ENTRY_PNPBIOS_TS1] = { { { 0x00000000, 0x00009200 } } },
+ [GDT_ENTRY_PNPBIOS_TS1] = { { { 0x00000000, 0x00009200 } } },
/* 16-bit data */
- [GDT_ENTRY_PNPBIOS_TS2] = { { { 0x00000000, 0x00009200 } } },
+ [GDT_ENTRY_PNPBIOS_TS2] = { { { 0x00000000, 0x00009200 } } },
/*
* The APM segments have byte granularity and their bases
* are set at run time. All have 64k limits.
*/
/* 32-bit code */
- [GDT_ENTRY_APMBIOS_BASE] = { { { 0x0000ffff, 0x00409a00 } } },
+ [GDT_ENTRY_APMBIOS_BASE] = { { { 0x0000ffff, 0x00409a00 } } },
/* 16-bit code */
- [GDT_ENTRY_APMBIOS_BASE+1] = { { { 0x0000ffff, 0x00009a00 } } },
+ [GDT_ENTRY_APMBIOS_BASE+1] = { { { 0x0000ffff, 0x00009a00 } } },
/* data */
- [GDT_ENTRY_APMBIOS_BASE+2] = { { { 0x0000ffff, 0x00409200 } } },
+ [GDT_ENTRY_APMBIOS_BASE+2] = { { { 0x0000ffff, 0x00409200 } } },
- [GDT_ENTRY_ESPFIX_SS] = { { { 0x00000000, 0x00c09200 } } },
- [GDT_ENTRY_PERCPU] = { { { 0x0000ffff, 0x00cf9200 } } },
+ [GDT_ENTRY_ESPFIX_SS] = { { { 0x00000000, 0x00c09200 } } },
+ [GDT_ENTRY_PERCPU] = { { { 0x0000ffff, 0x00cf9200 } } },
GDT_STACK_CANARY_INIT
#endif
} };
@@ -164,16 +164,17 @@ static inline int flag_is_changeable_p(u32 flag)
* the CPUID. Add "volatile" to not allow gcc to
* optimize the subsequent calls to this function.
*/
- asm volatile ("pushfl\n\t"
- "pushfl\n\t"
- "popl %0\n\t"
- "movl %0,%1\n\t"
- "xorl %2,%0\n\t"
- "pushl %0\n\t"
- "popfl\n\t"
- "pushfl\n\t"
- "popl %0\n\t"
- "popfl\n\t"
+ asm volatile ("pushfl \n\t"
+ "pushfl \n\t"
+ "popl %0 \n\t"
+ "movl %0, %1 \n\t"
+ "xorl %2, %0 \n\t"
+ "pushl %0 \n\t"
+ "popfl \n\t"
+ "pushfl \n\t"
+ "popl %0 \n\t"
+ "popfl \n\t"
+
: "=&r" (f1), "=&r" (f2)
: "ir" (flag));
@@ -188,18 +189,22 @@ static int __cpuinit have_cpuid_p(void)
static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
{
- if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr) {
- /* Disable processor serial number */
- unsigned long lo, hi;
- rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
- lo |= 0x200000;
- wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
- printk(KERN_NOTICE "CPU serial number disabled.\n");
- clear_cpu_cap(c, X86_FEATURE_PN);
-
- /* Disabling the serial number may affect the cpuid level */
- c->cpuid_level = cpuid_eax(0);
- }
+ unsigned long lo, hi;
+
+ if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
+ return;
+
+ /* Disable processor serial number: */
+
+ rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
+ lo |= 0x200000;
+ wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
+
+ printk(KERN_NOTICE "CPU serial number disabled.\n");
+ clear_cpu_cap(c, X86_FEATURE_PN);
+
+ /* Disabling the serial number may affect the cpuid level */
+ c->cpuid_level = cpuid_eax(0);
}
static int __init x86_serial_nr_setup(char *s)
@@ -232,6 +237,7 @@ struct cpuid_dependent_feature {
u32 feature;
u32 level;
};
+
static const struct cpuid_dependent_feature __cpuinitconst
cpuid_dependent_features[] = {
{ X86_FEATURE_MWAIT, 0x00000005 },
@@ -245,6 +251,9 @@ static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
const struct cpuid_dependent_feature *df;
for (df = cpuid_dependent_features; df->feature; df++) {
+
+ if (!cpu_has(c, df->feature))
+ continue;
/*
* Note: cpuid_level is set to -1 if unavailable, but
* extended_extended_level is set to 0 if unavailable
@@ -252,26 +261,26 @@ static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
* when signed; hence the weird messing around with
* signs here...
*/
- if (cpu_has(c, df->feature) &&
- ((s32)df->level < 0 ?
+ if (!((s32)df->level < 0 ?
(u32)df->level > (u32)c->extended_cpuid_level :
- (s32)df->level > (s32)c->cpuid_level)) {
- clear_cpu_cap(c, df->feature);
- if (warn)
- printk(KERN_WARNING
- "CPU: CPU feature %s disabled "
- "due to lack of CPUID level 0x%x\n",
- x86_cap_flags[df->feature],
- df->level);
- }
+ (s32)df->level > (s32)c->cpuid_level))
+ continue;
+
+ clear_cpu_cap(c, df->feature);
+ if (!warn)
+ continue;
+
+ printk(KERN_WARNING
+ "CPU: CPU feature %s disabled, no CPUID level 0x%x\n",
+ x86_cap_flags[df->feature], df->level);
}
}
/*
* Naming convention should be: <Name> [(<Codename>)]
* This table only is used unless init_<vendor>() below doesn't set it;
- * in particular, if CPUID levels 0x80000002..4 are supported, this isn't used
- *
+ * in particular, if CPUID levels 0x80000002..4 are supported, this
+ * isn't used
*/
/* Look up CPU names by table lookup. */
@@ -308,8 +317,10 @@ void load_percpu_segment(int cpu)
load_stack_canary_segment();
}
-/* Current gdt points %fs at the "master" per-cpu area: after this,
- * it's on the real one. */
+/*
+ * Current gdt points %fs at the "master" per-cpu area: after this,
+ * it's on the real one.
+ */
void switch_to_new_gdt(int cpu)
{
struct desc_ptr gdt_descr;
@@ -355,14 +366,16 @@ static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
if (c->extended_cpuid_level < 0x80000004)
return;
- v = (unsigned int *) c->x86_model_id;
+ v = (unsigned int *)c->x86_model_id;
cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
c->x86_model_id[48] = 0;
- /* Intel chips right-justify this string for some dumb reason;
- undo that brain damage */
+ /*
+ * Intel chips right-justify this string for some dumb reason;
+ * undo that brain damage:
+ */
p = q = &c->x86_model_id[0];
while (*p == ' ')
p++;
@@ -439,28 +452,30 @@ void __cpuinit detect_ht(struct cpuinfo_x86 *c)
if (smp_num_siblings == 1) {
printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
- } else if (smp_num_siblings > 1) {
+ goto out;
+ }
- if (smp_num_siblings > nr_cpu_ids) {
- pr_warning("CPU: Unsupported number of siblings %d",
- smp_num_siblings);
- smp_num_siblings = 1;
- return;
- }
+ if (smp_num_siblings <= 1)
+ goto out;
- index_msb = get_count_order(smp_num_siblings);
- c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,
- index_msb);
+ if (smp_num_siblings > nr_cpu_ids) {
+ pr_warning("CPU: Unsupported number of siblings %d",
+ smp_num_siblings);
+ smp_num_siblings = 1;
+ return;
+ }
- smp_num_siblings = smp_num_siblings / c->x86_max_cores;
+ index_msb = get_count_order(smp_num_siblings);
+ c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
- index_msb = get_count_order(smp_num_siblings);
+ smp_num_siblings = smp_num_siblings / c->x86_max_cores;
- core_bits = get_count_order(c->x86_max_cores);
+ index_msb = get_count_order(smp_num_siblings);
- c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
- ((1 << core_bits) - 1);
- }
+ core_bits = get_count_order(c->x86_max_cores);
+
+ c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
+ ((1 << core_bits) - 1);
out:
if ((c->x86_max_cores * smp_num_siblings) > 1) {
@@ -475,8 +490,8 @@ out:
static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
{
char *v = c->x86_vendor_id;
- int i;
static int printed;
+ int i;
for (i = 0; i < X86_VENDOR_NUM; i++) {
if (!cpu_devs[i])
@@ -485,6 +500,7 @@ static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
(cpu_devs[i]->c_ident[1] &&
!strcmp(v, cpu_devs[i]->c_ident[1]))) {
+
this_cpu = cpu_devs[i];
c->x86_vendor = this_cpu->c_x86_vendor;
return;
@@ -493,8 +509,9 @@ static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
if (!printed) {
printed++;
- printk(KERN_ERR "CPU: vendor_id '%s'"
- "unknown, using generic init.\n", v);
+ printk(KERN_ERR
+ "CPU: vendor_id '%s' unknown, using generic init.\n", v);
+
printk(KERN_ERR "CPU: Your system may be unstable.\n");
}
@@ -514,14 +531,17 @@ void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
/* Intel-defined flags: level 0x00000001 */
if (c->cpuid_level >= 0x00000001) {
u32 junk, tfms, cap0, misc;
+
cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
c->x86 = (tfms >> 8) & 0xf;
c->x86_model = (tfms >> 4) & 0xf;
c->x86_mask = tfms & 0xf;
+
if (c->x86 == 0xf)
c->x86 += (tfms >> 20) & 0xff;
if (c->x86 >= 0x6)
c->x86_model += ((tfms >> 16) & 0xf) << 4;
+
if (cap0 & (1<<19)) {
c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
c->x86_cache_alignment = c->x86_clflush_size;
@@ -537,6 +557,7 @@ static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
/* Intel-defined flags: level 0x00000001 */
if (c->cpuid_level >= 0x00000001) {
u32 capability, excap;
+
cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
c->x86_capability[0] = capability;
c->x86_capability[4] = excap;
@@ -545,6 +566,7 @@ static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
/* AMD-defined flags: level 0x80000001 */
xlvl = cpuid_eax(0x80000000);
c->extended_cpuid_level = xlvl;
+
if ((xlvl & 0xffff0000) == 0x80000000) {
if (xlvl >= 0x80000001) {
c->x86_capability[1] = cpuid_edx(0x80000001);
@@ -762,8 +784,8 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
squash_the_stupid_serial_number(c);
/*
- * The vendor-specific functions might have changed features. Now
- * we do "generic changes."
+ * The vendor-specific functions might have changed features.
+ * Now we do "generic changes."
*/
/* Filter out anything that depends on CPUID levels we don't have */
@@ -846,8 +868,8 @@ void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
}
struct msr_range {
- unsigned min;
- unsigned max;
+ unsigned min;
+ unsigned max;
};
static struct msr_range msr_range_array[] __cpuinitdata = {
@@ -859,14 +881,15 @@ static struct msr_range msr_range_array[] __cpuinitdata = {
static void __cpuinit print_cpu_msr(void)
{
+ unsigned index_min, index_max;
unsigned index;
u64 val;
int i;
- unsigned index_min, index_max;
for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
index_min = msr_range_array[i].min;
index_max = msr_range_array[i].max;
+
for (index = index_min; index < index_max; index++) {
if (rdmsrl_amd_safe(index, &val))
continue;
@@ -876,6 +899,7 @@ static void __cpuinit print_cpu_msr(void)
}
static int show_msr __cpuinitdata;
+
static __init int setup_show_msr(char *arg)
{
int num;
@@ -899,10 +923,12 @@ void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
{
char *vendor = NULL;
- if (c->x86_vendor < X86_VENDOR_NUM)
+ if (c->x86_vendor < X86_VENDOR_NUM) {
vendor = this_cpu->c_vendor;
- else if (c->cpuid_level >= 0)
- vendor = c->x86_vendor_id;
+ } else {
+ if (c->cpuid_level >= 0)
+ vendor = c->x86_vendor_id;
+ }
if (vendor && !strstr(c->x86_model_id, vendor))
printk(KERN_CONT "%s ", vendor);
@@ -929,10 +955,12 @@ void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
static __init int setup_disablecpuid(char *arg)
{
int bit;
+
if (get_option(&arg, &bit) && bit < NCAPINTS*32)
setup_clear_cpu_cap(bit);
else
return 0;
+
return 1;
}
__setup("clearcpuid=", setup_disablecpuid);
@@ -942,6 +970,7 @@ struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };
DEFINE_PER_CPU_FIRST(union irq_stack_union,
irq_stack_union) __aligned(PAGE_SIZE);
+
DEFINE_PER_CPU(char *, irq_stack_ptr) =
init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
@@ -951,6 +980,17 @@ EXPORT_PER_CPU_SYMBOL(kernel_stack);
DEFINE_PER_CPU(unsigned int, irq_count) = -1;
+/*
+ * Special IST stacks which the CPU switches to when it calls
+ * an IST-marked descriptor entry. Up to 7 stacks (hardware
+ * limit), all of them are 4K, except the debug stack which
+ * is 8K.
+ */
+static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
+ [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
+ [DEBUG_STACK - 1] = DEBUG_STKSZ
+};
+
static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ])
__aligned(PAGE_SIZE);
@@ -984,7 +1024,7 @@ unsigned long kernel_eflags;
*/
DEFINE_PER_CPU(struct orig_ist, orig_ist);
-#else /* x86_64 */
+#else /* CONFIG_X86_64 */
#ifdef CONFIG_CC_STACKPROTECTOR
DEFINE_PER_CPU(unsigned long, stack_canary);
@@ -996,9 +1036,10 @@ struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
memset(regs, 0, sizeof(struct pt_regs));
regs->fs = __KERNEL_PERCPU;
regs->gs = __KERNEL_STACK_CANARY;
+
return regs;
}
-#endif /* x86_64 */
+#endif /* CONFIG_X86_64 */
/*
* Clear all 6 debug registers:
@@ -1024,15 +1065,20 @@ static void clear_all_debug_regs(void)
* A lot of state is already set up in PDA init for 64 bit
*/
#ifdef CONFIG_X86_64
+
void __cpuinit cpu_init(void)
{
- int cpu = stack_smp_processor_id();
- struct tss_struct *t = &per_cpu(init_tss, cpu);
- struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
- unsigned long v;
+ struct orig_ist *orig_ist;
struct task_struct *me;
+ struct tss_struct *t;
+ unsigned long v;
+ int cpu;
int i;
+ cpu = stack_smp_processor_id();
+ t = &per_cpu(init_tss, cpu);
+ orig_ist = &per_cpu(orig_ist, cpu);
+
#ifdef CONFIG_NUMA
if (cpu != 0 && percpu_read(node_number) == 0 &&
cpu_to_node(cpu) != NUMA_NO_NODE)
@@ -1073,19 +1119,17 @@ void __cpuinit cpu_init(void)
* set up and load the per-CPU TSS
*/
if (!orig_ist->ist[0]) {
- static const unsigned int sizes[N_EXCEPTION_STACKS] = {
- [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
- [DEBUG_STACK - 1] = DEBUG_STKSZ
- };
char *estacks = per_cpu(exception_stacks, cpu);
+
for (v = 0; v < N_EXCEPTION_STACKS; v++) {
- estacks += sizes[v];
+ estacks += exception_stack_sizes[v];
orig_ist->ist[v] = t->x86_tss.ist[v] =
(unsigned long)estacks;
}
}
t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
+
/*
* <= is required because the CPU will access up to
* 8 bits beyond the end of the IO permission bitmap.
@@ -1187,5 +1231,4 @@ void __cpuinit cpu_init(void)
xsave_init();
}
-
#endif
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