linux/arch/x86/kernel/setup_percpu.c
Brian Gerst 947e76cdc3 x86: move stack_canary into irq_stack
Impact: x86_64 percpu area layout change, irq_stack now at the beginning

Now that the PDA is empty except for the stack canary, it can be removed.
The irqstack is moved to the start of the per-cpu section.  If the stack
protector is enabled, the canary overlaps the bottom 48 bytes of the irqstack.

tj: * updated subject
    * dropped asm relocation of irq_stack_ptr
    * updated comments a bit
    * rebased on top of stack canary changes

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-20 12:29:20 +09:00

410 lines
9.8 KiB
C

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/percpu.h>
#include <linux/kexec.h>
#include <linux/crash_dump.h>
#include <linux/smp.h>
#include <linux/topology.h>
#include <asm/sections.h>
#include <asm/processor.h>
#include <asm/setup.h>
#include <asm/mpspec.h>
#include <asm/apicdef.h>
#include <asm/highmem.h>
#include <asm/proto.h>
#include <asm/cpumask.h>
#ifdef CONFIG_DEBUG_PER_CPU_MAPS
# define DBG(x...) printk(KERN_DEBUG x)
#else
# define DBG(x...)
#endif
/*
* Could be inside CONFIG_HAVE_SETUP_PER_CPU_AREA with other stuff but
* voyager wants cpu_number too.
*/
#ifdef CONFIG_SMP
DEFINE_PER_CPU(int, cpu_number);
EXPORT_PER_CPU_SYMBOL(cpu_number);
#endif
#ifdef CONFIG_X86_LOCAL_APIC
unsigned int num_processors;
unsigned disabled_cpus __cpuinitdata;
/* Processor that is doing the boot up */
unsigned int boot_cpu_physical_apicid = -1U;
EXPORT_SYMBOL(boot_cpu_physical_apicid);
unsigned int max_physical_apicid;
/* Bitmask of physically existing CPUs */
physid_mask_t phys_cpu_present_map;
#endif
/*
* Map cpu index to physical APIC ID
*/
DEFINE_EARLY_PER_CPU(u16, x86_cpu_to_apicid, BAD_APICID);
DEFINE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid, BAD_APICID);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
#define X86_64_NUMA 1 /* (used later) */
DEFINE_PER_CPU(int, node_number) = 0;
EXPORT_PER_CPU_SYMBOL(node_number);
/*
* Map cpu index to node index
*/
DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
/*
* Which logical CPUs are on which nodes
*/
cpumask_t *node_to_cpumask_map;
EXPORT_SYMBOL(node_to_cpumask_map);
/*
* Setup node_to_cpumask_map
*/
static void __init setup_node_to_cpumask_map(void);
#else
static inline void setup_node_to_cpumask_map(void) { }
#endif
#ifdef CONFIG_X86_64
/* correctly size the local cpu masks */
static void setup_cpu_local_masks(void)
{
alloc_bootmem_cpumask_var(&cpu_initialized_mask);
alloc_bootmem_cpumask_var(&cpu_callin_mask);
alloc_bootmem_cpumask_var(&cpu_callout_mask);
alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
}
#else /* CONFIG_X86_32 */
static inline void setup_cpu_local_masks(void)
{
}
#endif /* CONFIG_X86_32 */
#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
/*
* Copy data used in early init routines from the initial arrays to the
* per cpu data areas. These arrays then become expendable and the
* *_early_ptr's are zeroed indicating that the static arrays are gone.
*/
static void __init setup_per_cpu_maps(void)
{
int cpu;
for_each_possible_cpu(cpu) {
per_cpu(x86_cpu_to_apicid, cpu) =
early_per_cpu_map(x86_cpu_to_apicid, cpu);
per_cpu(x86_bios_cpu_apicid, cpu) =
early_per_cpu_map(x86_bios_cpu_apicid, cpu);
#ifdef X86_64_NUMA
per_cpu(x86_cpu_to_node_map, cpu) =
early_per_cpu_map(x86_cpu_to_node_map, cpu);
#endif
}
/* indicate the early static arrays will soon be gone */
early_per_cpu_ptr(x86_cpu_to_apicid) = NULL;
early_per_cpu_ptr(x86_bios_cpu_apicid) = NULL;
#ifdef X86_64_NUMA
early_per_cpu_ptr(x86_cpu_to_node_map) = NULL;
#endif
}
#ifdef CONFIG_X86_64
unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = {
[0] = (unsigned long)__per_cpu_load,
};
#else
unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
#endif
EXPORT_SYMBOL(__per_cpu_offset);
/*
* Great future plan:
* Declare PDA itself and support (irqstack,tss,pgd) as per cpu data.
* Always point %gs to its beginning
*/
void __init setup_per_cpu_areas(void)
{
ssize_t size, old_size;
char *ptr;
int cpu;
unsigned long align = 1;
/* Copy section for each CPU (we discard the original) */
old_size = PERCPU_ENOUGH_ROOM;
align = max_t(unsigned long, PAGE_SIZE, align);
size = roundup(old_size, align);
pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",
NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
pr_info("PERCPU: Allocating %zd bytes of per cpu data\n", size);
for_each_possible_cpu(cpu) {
#ifndef CONFIG_NEED_MULTIPLE_NODES
ptr = __alloc_bootmem(size, align,
__pa(MAX_DMA_ADDRESS));
#else
int node = early_cpu_to_node(cpu);
if (!node_online(node) || !NODE_DATA(node)) {
ptr = __alloc_bootmem(size, align,
__pa(MAX_DMA_ADDRESS));
pr_info("cpu %d has no node %d or node-local memory\n",
cpu, node);
pr_debug("per cpu data for cpu%d at %016lx\n",
cpu, __pa(ptr));
} else {
ptr = __alloc_bootmem_node(NODE_DATA(node), size, align,
__pa(MAX_DMA_ADDRESS));
pr_debug("per cpu data for cpu%d on node%d at %016lx\n",
cpu, node, __pa(ptr));
}
#endif
memcpy(ptr, __per_cpu_load, __per_cpu_end - __per_cpu_start);
per_cpu_offset(cpu) = ptr - __per_cpu_start;
per_cpu(this_cpu_off, cpu) = per_cpu_offset(cpu);
per_cpu(cpu_number, cpu) = cpu;
#ifdef CONFIG_X86_64
per_cpu(irq_stack_ptr, cpu) =
per_cpu(irq_stack_union.irq_stack, cpu) + IRQ_STACK_SIZE - 64;
/*
* Up to this point, CPU0 has been using .data.init
* area. Reload %gs offset for CPU0.
*/
if (cpu == 0)
load_gs_base(cpu);
#endif
DBG("PERCPU: cpu %4d %p\n", cpu, ptr);
}
/* Setup percpu data maps */
setup_per_cpu_maps();
/* Setup node to cpumask map */
setup_node_to_cpumask_map();
/* Setup cpu initialized, callin, callout masks */
setup_cpu_local_masks();
}
#endif
#ifdef X86_64_NUMA
/*
* Allocate node_to_cpumask_map based on number of available nodes
* Requires node_possible_map to be valid.
*
* Note: node_to_cpumask() is not valid until after this is done.
* (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
*/
static void __init setup_node_to_cpumask_map(void)
{
unsigned int node, num = 0;
cpumask_t *map;
/* setup nr_node_ids if not done yet */
if (nr_node_ids == MAX_NUMNODES) {
for_each_node_mask(node, node_possible_map)
num = node;
nr_node_ids = num + 1;
}
/* allocate the map */
map = alloc_bootmem_low(nr_node_ids * sizeof(cpumask_t));
DBG("node_to_cpumask_map at %p for %d nodes\n", map, nr_node_ids);
pr_debug("Node to cpumask map at %p for %d nodes\n",
map, nr_node_ids);
/* node_to_cpumask() will now work */
node_to_cpumask_map = map;
}
void __cpuinit numa_set_node(int cpu, int node)
{
int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
/* early setting, no percpu area yet */
if (cpu_to_node_map) {
cpu_to_node_map[cpu] = node;
return;
}
#ifdef CONFIG_DEBUG_PER_CPU_MAPS
if (cpu >= nr_cpu_ids || !per_cpu_offset(cpu)) {
printk(KERN_ERR "numa_set_node: invalid cpu# (%d)\n", cpu);
dump_stack();
return;
}
#endif
per_cpu(x86_cpu_to_node_map, cpu) = node;
if (node != NUMA_NO_NODE)
per_cpu(node_number, cpu) = node;
}
void __cpuinit numa_clear_node(int cpu)
{
numa_set_node(cpu, NUMA_NO_NODE);
}
#ifndef CONFIG_DEBUG_PER_CPU_MAPS
void __cpuinit numa_add_cpu(int cpu)
{
cpu_set(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
}
void __cpuinit numa_remove_cpu(int cpu)
{
cpu_clear(cpu, node_to_cpumask_map[early_cpu_to_node(cpu)]);
}
#else /* CONFIG_DEBUG_PER_CPU_MAPS */
/*
* --------- debug versions of the numa functions ---------
*/
static void __cpuinit numa_set_cpumask(int cpu, int enable)
{
int node = early_cpu_to_node(cpu);
cpumask_t *mask;
char buf[64];
if (node_to_cpumask_map == NULL) {
printk(KERN_ERR "node_to_cpumask_map NULL\n");
dump_stack();
return;
}
mask = &node_to_cpumask_map[node];
if (enable)
cpu_set(cpu, *mask);
else
cpu_clear(cpu, *mask);
cpulist_scnprintf(buf, sizeof(buf), mask);
printk(KERN_DEBUG "%s cpu %d node %d: mask now %s\n",
enable ? "numa_add_cpu" : "numa_remove_cpu", cpu, node, buf);
}
void __cpuinit numa_add_cpu(int cpu)
{
numa_set_cpumask(cpu, 1);
}
void __cpuinit numa_remove_cpu(int cpu)
{
numa_set_cpumask(cpu, 0);
}
int cpu_to_node(int cpu)
{
if (early_per_cpu_ptr(x86_cpu_to_node_map)) {
printk(KERN_WARNING
"cpu_to_node(%d): usage too early!\n", cpu);
dump_stack();
return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
}
return per_cpu(x86_cpu_to_node_map, cpu);
}
EXPORT_SYMBOL(cpu_to_node);
/*
* Same function as cpu_to_node() but used if called before the
* per_cpu areas are setup.
*/
int early_cpu_to_node(int cpu)
{
if (early_per_cpu_ptr(x86_cpu_to_node_map))
return early_per_cpu_ptr(x86_cpu_to_node_map)[cpu];
if (!per_cpu_offset(cpu)) {
printk(KERN_WARNING
"early_cpu_to_node(%d): no per_cpu area!\n", cpu);
dump_stack();
return NUMA_NO_NODE;
}
return per_cpu(x86_cpu_to_node_map, cpu);
}
/* empty cpumask */
static const cpumask_t cpu_mask_none;
/*
* Returns a pointer to the bitmask of CPUs on Node 'node'.
*/
const cpumask_t *cpumask_of_node(int node)
{
if (node_to_cpumask_map == NULL) {
printk(KERN_WARNING
"cpumask_of_node(%d): no node_to_cpumask_map!\n",
node);
dump_stack();
return (const cpumask_t *)&cpu_online_map;
}
if (node >= nr_node_ids) {
printk(KERN_WARNING
"cpumask_of_node(%d): node > nr_node_ids(%d)\n",
node, nr_node_ids);
dump_stack();
return &cpu_mask_none;
}
return &node_to_cpumask_map[node];
}
EXPORT_SYMBOL(cpumask_of_node);
/*
* Returns a bitmask of CPUs on Node 'node'.
*
* Side note: this function creates the returned cpumask on the stack
* so with a high NR_CPUS count, excessive stack space is used. The
* node_to_cpumask_ptr function should be used whenever possible.
*/
cpumask_t node_to_cpumask(int node)
{
if (node_to_cpumask_map == NULL) {
printk(KERN_WARNING
"node_to_cpumask(%d): no node_to_cpumask_map!\n", node);
dump_stack();
return cpu_online_map;
}
if (node >= nr_node_ids) {
printk(KERN_WARNING
"node_to_cpumask(%d): node > nr_node_ids(%d)\n",
node, nr_node_ids);
dump_stack();
return cpu_mask_none;
}
return node_to_cpumask_map[node];
}
EXPORT_SYMBOL(node_to_cpumask);
/*
* --------- end of debug versions of the numa functions ---------
*/
#endif /* CONFIG_DEBUG_PER_CPU_MAPS */
#endif /* X86_64_NUMA */