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linux-next/arch/ia64/kernel/smpboot.c
Paul Gortmaker ccce9bb83e [IA64] Delete __cpuinit usage from all ia64 users 
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the ia64 uses of the __cpuinit macros.

[1] https://lkml.org/lkml/2013/5/20/589

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-06-24 15:44:27 -07:00

859 lines
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/*
* SMP boot-related support
*
* Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
* Copyright (C) 2001, 2004-2005 Intel Corp
* Rohit Seth <rohit.seth@intel.com>
* Suresh Siddha <suresh.b.siddha@intel.com>
* Gordon Jin <gordon.jin@intel.com>
* Ashok Raj <ashok.raj@intel.com>
*
* 01/05/16 Rohit Seth <rohit.seth@intel.com> Moved SMP booting functions from smp.c to here.
* 01/04/27 David Mosberger <davidm@hpl.hp.com> Added ITC synching code.
* 02/07/31 David Mosberger <davidm@hpl.hp.com> Switch over to hotplug-CPU boot-sequence.
* smp_boot_cpus()/smp_commence() is replaced by
* smp_prepare_cpus()/__cpu_up()/smp_cpus_done().
* 04/06/21 Ashok Raj <ashok.raj@intel.com> Added CPU Hotplug Support
* 04/12/26 Jin Gordon <gordon.jin@intel.com>
* 04/12/26 Rohit Seth <rohit.seth@intel.com>
* Add multi-threading and multi-core detection
* 05/01/30 Suresh Siddha <suresh.b.siddha@intel.com>
* Setup cpu_sibling_map and cpu_core_map
*/
#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/bootmem.h>
#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/mm.h>
#include <linux/notifier.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/efi.h>
#include <linux/percpu.h>
#include <linux/bitops.h>
#include <linux/atomic.h>
#include <asm/cache.h>
#include <asm/current.h>
#include <asm/delay.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/machvec.h>
#include <asm/mca.h>
#include <asm/page.h>
#include <asm/paravirt.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/sal.h>
#include <asm/tlbflush.h>
#include <asm/unistd.h>
#include <asm/sn/arch.h>
#define SMP_DEBUG 0
#if SMP_DEBUG
#define Dprintk(x...) printk(x)
#else
#define Dprintk(x...)
#endif
#ifdef CONFIG_HOTPLUG_CPU
#ifdef CONFIG_PERMIT_BSP_REMOVE
#define bsp_remove_ok 1
#else
#define bsp_remove_ok 0
#endif
/*
* Global array allocated for NR_CPUS at boot time
*/
struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS];
/*
* start_ap in head.S uses this to store current booting cpu
* info.
*/
struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0];
#define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]);
#else
#define set_brendez_area(x)
#endif
/*
* ITC synchronization related stuff:
*/
#define MASTER (0)
#define SLAVE (SMP_CACHE_BYTES/8)
#define NUM_ROUNDS 64 /* magic value */
#define NUM_ITERS 5 /* likewise */
static DEFINE_SPINLOCK(itc_sync_lock);
static volatile unsigned long go[SLAVE + 1];
#define DEBUG_ITC_SYNC 0
extern void start_ap (void);
extern unsigned long ia64_iobase;
struct task_struct *task_for_booting_cpu;
/*
* State for each CPU
*/
DEFINE_PER_CPU(int, cpu_state);
cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
EXPORT_SYMBOL(cpu_core_map);
DEFINE_PER_CPU_SHARED_ALIGNED(cpumask_t, cpu_sibling_map);
EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
int smp_num_siblings = 1;
/* which logical CPU number maps to which CPU (physical APIC ID) */
volatile int ia64_cpu_to_sapicid[NR_CPUS];
EXPORT_SYMBOL(ia64_cpu_to_sapicid);
static volatile cpumask_t cpu_callin_map;
struct smp_boot_data smp_boot_data __initdata;
unsigned long ap_wakeup_vector = -1; /* External Int use to wakeup APs */
char __initdata no_int_routing;
unsigned char smp_int_redirect; /* are INT and IPI redirectable by the chipset? */
#ifdef CONFIG_FORCE_CPEI_RETARGET
#define CPEI_OVERRIDE_DEFAULT (1)
#else
#define CPEI_OVERRIDE_DEFAULT (0)
#endif
unsigned int force_cpei_retarget = CPEI_OVERRIDE_DEFAULT;
static int __init
cmdl_force_cpei(char *str)
{
int value=0;
get_option (&str, &value);
force_cpei_retarget = value;
return 1;
}
__setup("force_cpei=", cmdl_force_cpei);
static int __init
nointroute (char *str)
{
no_int_routing = 1;
printk ("no_int_routing on\n");
return 1;
}
__setup("nointroute", nointroute);
static void fix_b0_for_bsp(void)
{
#ifdef CONFIG_HOTPLUG_CPU
int cpuid;
static int fix_bsp_b0 = 1;
cpuid = smp_processor_id();
/*
* Cache the b0 value on the first AP that comes up
*/
if (!(fix_bsp_b0 && cpuid))
return;
sal_boot_rendez_state[0].br[0] = sal_boot_rendez_state[cpuid].br[0];
printk ("Fixed BSP b0 value from CPU %d\n", cpuid);
fix_bsp_b0 = 0;
#endif
}
void
sync_master (void *arg)
{
unsigned long flags, i;
go[MASTER] = 0;
local_irq_save(flags);
{
for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
while (!go[MASTER])
cpu_relax();
go[MASTER] = 0;
go[SLAVE] = ia64_get_itc();
}
}
local_irq_restore(flags);
}
/*
* Return the number of cycles by which our itc differs from the itc on the master
* (time-keeper) CPU. A positive number indicates our itc is ahead of the master,
* negative that it is behind.
*/
static inline long
get_delta (long *rt, long *master)
{
unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
unsigned long tcenter, t0, t1, tm;
long i;
for (i = 0; i < NUM_ITERS; ++i) {
t0 = ia64_get_itc();
go[MASTER] = 1;
while (!(tm = go[SLAVE]))
cpu_relax();
go[SLAVE] = 0;
t1 = ia64_get_itc();
if (t1 - t0 < best_t1 - best_t0)
best_t0 = t0, best_t1 = t1, best_tm = tm;
}
*rt = best_t1 - best_t0;
*master = best_tm - best_t0;
/* average best_t0 and best_t1 without overflow: */
tcenter = (best_t0/2 + best_t1/2);
if (best_t0 % 2 + best_t1 % 2 == 2)
++tcenter;
return tcenter - best_tm;
}
/*
* Synchronize ar.itc of the current (slave) CPU with the ar.itc of the MASTER CPU
* (normally the time-keeper CPU). We use a closed loop to eliminate the possibility of
* unaccounted-for errors (such as getting a machine check in the middle of a calibration
* step). The basic idea is for the slave to ask the master what itc value it has and to
* read its own itc before and after the master responds. Each iteration gives us three
* timestamps:
*
* slave master
*
* t0 ---\
* ---\
* --->
* tm
* /---
* /---
* t1 <---
*
*
* The goal is to adjust the slave's ar.itc such that tm falls exactly half-way between t0
* and t1. If we achieve this, the clocks are synchronized provided the interconnect
* between the slave and the master is symmetric. Even if the interconnect were
* asymmetric, we would still know that the synchronization error is smaller than the
* roundtrip latency (t0 - t1).
*
* When the interconnect is quiet and symmetric, this lets us synchronize the itc to
* within one or two cycles. However, we can only *guarantee* that the synchronization is
* accurate to within a round-trip time, which is typically in the range of several
* hundred cycles (e.g., ~500 cycles). In practice, this means that the itc's are usually
* almost perfectly synchronized, but we shouldn't assume that the accuracy is much better
* than half a micro second or so.
*/
void
ia64_sync_itc (unsigned int master)
{
long i, delta, adj, adjust_latency = 0, done = 0;
unsigned long flags, rt, master_time_stamp, bound;
#if DEBUG_ITC_SYNC
struct {
long rt; /* roundtrip time */
long master; /* master's timestamp */
long diff; /* difference between midpoint and master's timestamp */
long lat; /* estimate of itc adjustment latency */
} t[NUM_ROUNDS];
#endif
/*
* Make sure local timer ticks are disabled while we sync. If
* they were enabled, we'd have to worry about nasty issues
* like setting the ITC ahead of (or a long time before) the
* next scheduled tick.
*/
BUG_ON((ia64_get_itv() & (1 << 16)) == 0);
go[MASTER] = 1;
if (smp_call_function_single(master, sync_master, NULL, 0) < 0) {
printk(KERN_ERR "sync_itc: failed to get attention of CPU %u!\n", master);
return;
}
while (go[MASTER])
cpu_relax(); /* wait for master to be ready */
spin_lock_irqsave(&itc_sync_lock, flags);
{
for (i = 0; i < NUM_ROUNDS; ++i) {
delta = get_delta(&rt, &master_time_stamp);
if (delta == 0) {
done = 1; /* let's lock on to this... */
bound = rt;
}
if (!done) {
if (i > 0) {
adjust_latency += -delta;
adj = -delta + adjust_latency/4;
} else
adj = -delta;
ia64_set_itc(ia64_get_itc() + adj);
}
#if DEBUG_ITC_SYNC
t[i].rt = rt;
t[i].master = master_time_stamp;
t[i].diff = delta;
t[i].lat = adjust_latency/4;
#endif
}
}
spin_unlock_irqrestore(&itc_sync_lock, flags);
#if DEBUG_ITC_SYNC
for (i = 0; i < NUM_ROUNDS; ++i)
printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
t[i].rt, t[i].master, t[i].diff, t[i].lat);
#endif
printk(KERN_INFO "CPU %d: synchronized ITC with CPU %u (last diff %ld cycles, "
"maxerr %lu cycles)\n", smp_processor_id(), master, delta, rt);
}
/*
* Ideally sets up per-cpu profiling hooks. Doesn't do much now...
*/
static inline void smp_setup_percpu_timer(void)
{
}
static void
smp_callin (void)
{
int cpuid, phys_id, itc_master;
struct cpuinfo_ia64 *last_cpuinfo, *this_cpuinfo;
extern void ia64_init_itm(void);
extern volatile int time_keeper_id;
#ifdef CONFIG_PERFMON
extern void pfm_init_percpu(void);
#endif
cpuid = smp_processor_id();
phys_id = hard_smp_processor_id();
itc_master = time_keeper_id;
if (cpu_online(cpuid)) {
printk(KERN_ERR "huh, phys CPU#0x%x, CPU#0x%x already present??\n",
phys_id, cpuid);
BUG();
}
fix_b0_for_bsp();
/*
* numa_node_id() works after this.
*/
set_numa_node(cpu_to_node_map[cpuid]);
set_numa_mem(local_memory_node(cpu_to_node_map[cpuid]));
spin_lock(&vector_lock);
/* Setup the per cpu irq handling data structures */
__setup_vector_irq(cpuid);
notify_cpu_starting(cpuid);
set_cpu_online(cpuid, true);
per_cpu(cpu_state, cpuid) = CPU_ONLINE;
spin_unlock(&vector_lock);
smp_setup_percpu_timer();
ia64_mca_cmc_vector_setup(); /* Setup vector on AP */
#ifdef CONFIG_PERFMON
pfm_init_percpu();
#endif
local_irq_enable();
if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
/*
* Synchronize the ITC with the BP. Need to do this after irqs are
* enabled because ia64_sync_itc() calls smp_call_function_single(), which
* calls spin_unlock_bh(), which calls spin_unlock_bh(), which calls
* local_bh_enable(), which bugs out if irqs are not enabled...
*/
Dprintk("Going to syncup ITC with ITC Master.\n");
ia64_sync_itc(itc_master);
}
/*
* Get our bogomips.
*/
ia64_init_itm();
/*
* Delay calibration can be skipped if new processor is identical to the
* previous processor.
*/
last_cpuinfo = cpu_data(cpuid - 1);
this_cpuinfo = local_cpu_data;
if (last_cpuinfo->itc_freq != this_cpuinfo->itc_freq ||
last_cpuinfo->proc_freq != this_cpuinfo->proc_freq ||
last_cpuinfo->features != this_cpuinfo->features ||
last_cpuinfo->revision != this_cpuinfo->revision ||
last_cpuinfo->family != this_cpuinfo->family ||
last_cpuinfo->archrev != this_cpuinfo->archrev ||
last_cpuinfo->model != this_cpuinfo->model)
calibrate_delay();
local_cpu_data->loops_per_jiffy = loops_per_jiffy;
/*
* Allow the master to continue.
*/
cpu_set(cpuid, cpu_callin_map);
Dprintk("Stack on CPU %d at about %p\n",cpuid, &cpuid);
}
/*
* Activate a secondary processor. head.S calls this.
*/
int
start_secondary (void *unused)
{
/* Early console may use I/O ports */
ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));
#ifndef CONFIG_PRINTK_TIME
Dprintk("start_secondary: starting CPU 0x%x\n", hard_smp_processor_id());
#endif
efi_map_pal_code();
cpu_init();
preempt_disable();
smp_callin();
cpu_startup_entry(CPUHP_ONLINE);
return 0;
}
static int
do_boot_cpu (int sapicid, int cpu, struct task_struct *idle)
{
int timeout;
task_for_booting_cpu = idle;
Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);
set_brendez_area(cpu);
platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
/*
* Wait 10s total for the AP to start
*/
Dprintk("Waiting on callin_map ...");
for (timeout = 0; timeout < 100000; timeout++) {
if (cpu_isset(cpu, cpu_callin_map))
break; /* It has booted */
udelay(100);
}
Dprintk("\n");
if (!cpu_isset(cpu, cpu_callin_map)) {
printk(KERN_ERR "Processor 0x%x/0x%x is stuck.\n", cpu, sapicid);
ia64_cpu_to_sapicid[cpu] = -1;
set_cpu_online(cpu, false); /* was set in smp_callin() */
return -EINVAL;
}
return 0;
}
static int __init
decay (char *str)
{
int ticks;
get_option (&str, &ticks);
return 1;
}
__setup("decay=", decay);
/*
* Initialize the logical CPU number to SAPICID mapping
*/
void __init
smp_build_cpu_map (void)
{
int sapicid, cpu, i;
int boot_cpu_id = hard_smp_processor_id();
for (cpu = 0; cpu < NR_CPUS; cpu++) {
ia64_cpu_to_sapicid[cpu] = -1;
}
ia64_cpu_to_sapicid[0] = boot_cpu_id;
init_cpu_present(cpumask_of(0));
set_cpu_possible(0, true);
for (cpu = 1, i = 0; i < smp_boot_data.cpu_count; i++) {
sapicid = smp_boot_data.cpu_phys_id[i];
if (sapicid == boot_cpu_id)
continue;
set_cpu_present(cpu, true);
set_cpu_possible(cpu, true);
ia64_cpu_to_sapicid[cpu] = sapicid;
cpu++;
}
}
/*
* Cycle through the APs sending Wakeup IPIs to boot each.
*/
void __init
smp_prepare_cpus (unsigned int max_cpus)
{
int boot_cpu_id = hard_smp_processor_id();
/*
* Initialize the per-CPU profiling counter/multiplier
*/
smp_setup_percpu_timer();
cpu_set(0, cpu_callin_map);
local_cpu_data->loops_per_jiffy = loops_per_jiffy;
ia64_cpu_to_sapicid[0] = boot_cpu_id;
printk(KERN_INFO "Boot processor id 0x%x/0x%x\n", 0, boot_cpu_id);
current_thread_info()->cpu = 0;
/*
* If SMP should be disabled, then really disable it!
*/
if (!max_cpus) {
printk(KERN_INFO "SMP mode deactivated.\n");
init_cpu_online(cpumask_of(0));
init_cpu_present(cpumask_of(0));
init_cpu_possible(cpumask_of(0));
return;
}
}
void smp_prepare_boot_cpu(void)
{
set_cpu_online(smp_processor_id(), true);
cpu_set(smp_processor_id(), cpu_callin_map);
set_numa_node(cpu_to_node_map[smp_processor_id()]);
per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
paravirt_post_smp_prepare_boot_cpu();
}
#ifdef CONFIG_HOTPLUG_CPU
static inline void
clear_cpu_sibling_map(int cpu)
{
int i;
for_each_cpu_mask(i, per_cpu(cpu_sibling_map, cpu))
cpu_clear(cpu, per_cpu(cpu_sibling_map, i));
for_each_cpu_mask(i, cpu_core_map[cpu])
cpu_clear(cpu, cpu_core_map[i]);
per_cpu(cpu_sibling_map, cpu) = cpu_core_map[cpu] = CPU_MASK_NONE;
}
static void
remove_siblinginfo(int cpu)
{
int last = 0;
if (cpu_data(cpu)->threads_per_core == 1 &&
cpu_data(cpu)->cores_per_socket == 1) {
cpu_clear(cpu, cpu_core_map[cpu]);
cpu_clear(cpu, per_cpu(cpu_sibling_map, cpu));
return;
}
last = (cpus_weight(cpu_core_map[cpu]) == 1 ? 1 : 0);
/* remove it from all sibling map's */
clear_cpu_sibling_map(cpu);
}
extern void fixup_irqs(void);
int migrate_platform_irqs(unsigned int cpu)
{
int new_cpei_cpu;
struct irq_data *data = NULL;
const struct cpumask *mask;
int retval = 0;
/*
* dont permit CPEI target to removed.
*/
if (cpe_vector > 0 && is_cpu_cpei_target(cpu)) {
printk ("CPU (%d) is CPEI Target\n", cpu);
if (can_cpei_retarget()) {
/*
* Now re-target the CPEI to a different processor
*/
new_cpei_cpu = cpumask_any(cpu_online_mask);
mask = cpumask_of(new_cpei_cpu);
set_cpei_target_cpu(new_cpei_cpu);
data = irq_get_irq_data(ia64_cpe_irq);
/*
* Switch for now, immediately, we need to do fake intr
* as other interrupts, but need to study CPEI behaviour with
* polling before making changes.
*/
if (data && data->chip) {
data->chip->irq_disable(data);
data->chip->irq_set_affinity(data, mask, false);
data->chip->irq_enable(data);
printk ("Re-targeting CPEI to cpu %d\n", new_cpei_cpu);
}
}
if (!data) {
printk ("Unable to retarget CPEI, offline cpu [%d] failed\n", cpu);
retval = -EBUSY;
}
}
return retval;
}
/* must be called with cpucontrol mutex held */
int __cpu_disable(void)
{
int cpu = smp_processor_id();
/*
* dont permit boot processor for now
*/
if (cpu == 0 && !bsp_remove_ok) {
printk ("Your platform does not support removal of BSP\n");
return (-EBUSY);
}
if (ia64_platform_is("sn2")) {
if (!sn_cpu_disable_allowed(cpu))
return -EBUSY;
}
set_cpu_online(cpu, false);
if (migrate_platform_irqs(cpu)) {
set_cpu_online(cpu, true);
return -EBUSY;
}
remove_siblinginfo(cpu);
fixup_irqs();
local_flush_tlb_all();
cpu_clear(cpu, cpu_callin_map);
return 0;
}
void __cpu_die(unsigned int cpu)
{
unsigned int i;
for (i = 0; i < 100; i++) {
/* They ack this in play_dead by setting CPU_DEAD */
if (per_cpu(cpu_state, cpu) == CPU_DEAD)
{
printk ("CPU %d is now offline\n", cpu);
return;
}
msleep(100);
}
printk(KERN_ERR "CPU %u didn't die...\n", cpu);
}
#endif /* CONFIG_HOTPLUG_CPU */
void
smp_cpus_done (unsigned int dummy)
{
int cpu;
unsigned long bogosum = 0;
/*
* Allow the user to impress friends.
*/
for_each_online_cpu(cpu) {
bogosum += cpu_data(cpu)->loops_per_jiffy;
}
printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
(int)num_online_cpus(), bogosum/(500000/HZ), (bogosum/(5000/HZ))%100);
}
static inline void set_cpu_sibling_map(int cpu)
{
int i;
for_each_online_cpu(i) {
if ((cpu_data(cpu)->socket_id == cpu_data(i)->socket_id)) {
cpu_set(i, cpu_core_map[cpu]);
cpu_set(cpu, cpu_core_map[i]);
if (cpu_data(cpu)->core_id == cpu_data(i)->core_id) {
cpu_set(i, per_cpu(cpu_sibling_map, cpu));
cpu_set(cpu, per_cpu(cpu_sibling_map, i));
}
}
}
}
int
__cpu_up(unsigned int cpu, struct task_struct *tidle)
{
int ret;
int sapicid;
sapicid = ia64_cpu_to_sapicid[cpu];
if (sapicid == -1)
return -EINVAL;
/*
* Already booted cpu? not valid anymore since we dont
* do idle loop tightspin anymore.
*/
if (cpu_isset(cpu, cpu_callin_map))
return -EINVAL;
per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
/* Processor goes to start_secondary(), sets online flag */
ret = do_boot_cpu(sapicid, cpu, tidle);
if (ret < 0)
return ret;
if (cpu_data(cpu)->threads_per_core == 1 &&
cpu_data(cpu)->cores_per_socket == 1) {
cpu_set(cpu, per_cpu(cpu_sibling_map, cpu));
cpu_set(cpu, cpu_core_map[cpu]);
return 0;
}
set_cpu_sibling_map(cpu);
return 0;
}
/*
* Assume that CPUs have been discovered by some platform-dependent interface. For
* SoftSDV/Lion, that would be ACPI.
*
* Setup of the IPI irq handler is done in irq.c:init_IRQ_SMP().
*/
void __init
init_smp_config(void)
{
struct fptr {
unsigned long fp;
unsigned long gp;
} *ap_startup;
long sal_ret;
/* Tell SAL where to drop the APs. */
ap_startup = (struct fptr *) start_ap;
sal_ret = ia64_sal_set_vectors(SAL_VECTOR_OS_BOOT_RENDEZ,
ia64_tpa(ap_startup->fp), ia64_tpa(ap_startup->gp), 0, 0, 0, 0);
if (sal_ret < 0)
printk(KERN_ERR "SMP: Can't set SAL AP Boot Rendezvous: %s\n",
ia64_sal_strerror(sal_ret));
}
/*
* identify_siblings(cpu) gets called from identify_cpu. This populates the
* information related to logical execution units in per_cpu_data structure.
*/
void identify_siblings(struct cpuinfo_ia64 *c)
{
long status;
u16 pltid;
pal_logical_to_physical_t info;
status = ia64_pal_logical_to_phys(-1, &info);
if (status != PAL_STATUS_SUCCESS) {
if (status != PAL_STATUS_UNIMPLEMENTED) {
printk(KERN_ERR
"ia64_pal_logical_to_phys failed with %ld\n",
status);
return;
}
info.overview_ppid = 0;
info.overview_cpp = 1;
info.overview_tpc = 1;
}
status = ia64_sal_physical_id_info(&pltid);
if (status != PAL_STATUS_SUCCESS) {
if (status != PAL_STATUS_UNIMPLEMENTED)
printk(KERN_ERR
"ia64_sal_pltid failed with %ld\n",
status);
return;
}
c->socket_id = (pltid << 8) | info.overview_ppid;
if (info.overview_cpp == 1 && info.overview_tpc == 1)
return;
c->cores_per_socket = info.overview_cpp;
c->threads_per_core = info.overview_tpc;
c->num_log = info.overview_num_log;
c->core_id = info.log1_cid;
c->thread_id = info.log1_tid;
}
/*
* returns non zero, if multi-threading is enabled
* on at least one physical package. Due to hotplug cpu
* and (maxcpus=), all threads may not necessarily be enabled
* even though the processor supports multi-threading.
*/
int is_multithreading_enabled(void)
{
int i, j;
for_each_present_cpu(i) {
for_each_present_cpu(j) {
if (j == i)
continue;
if ((cpu_data(j)->socket_id == cpu_data(i)->socket_id)) {
if (cpu_data(j)->core_id == cpu_data(i)->core_id)
return 1;
}
}
}
return 0;
}
EXPORT_SYMBOL_GPL(is_multithreading_enabled);
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