* Andi Kleen : Converted to new state machine.
* Various cleanups.
* Probably mostly hotplug CPU ready now.
+ * Ashok Raj : CPU hotplug support
*/
#include <linux/mm.h>
#include <linux/kernel_stat.h>
#include <linux/smp_lock.h>
-#include <linux/irq.h>
#include <linux/bootmem.h>
#include <linux/thread_info.h>
#include <linux/module.h>
#include <asm/tlbflush.h>
#include <asm/proto.h>
#include <asm/nmi.h>
-
-/* Change for real CPU hotplug. Note other files need to be fixed
- first too. */
-#define __cpuinit __init
-#define __cpuinitdata __initdata
+#include <asm/irq.h>
+#include <asm/hw_irq.h>
+#include <asm/numa.h>
/* Number of siblings per CPU package */
int smp_num_siblings = 1;
/* Package ID of each logical CPU */
-u8 phys_proc_id[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
-u8 cpu_core_id[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
-EXPORT_SYMBOL(phys_proc_id);
-EXPORT_SYMBOL(cpu_core_id);
+u8 phys_proc_id[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
+/* core ID of each logical CPU */
+u8 cpu_core_id[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
+
+/* Last level cache ID of each logical CPU */
+u8 cpu_llc_id[NR_CPUS] __cpuinitdata = {[0 ... NR_CPUS-1] = BAD_APICID};
/* Bitmask of currently online CPUs */
-cpumask_t cpu_online_map;
+cpumask_t cpu_online_map __read_mostly;
EXPORT_SYMBOL(cpu_online_map);
/* Set when the idlers are all forked */
int smp_threads_ready;
-cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned;
-cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
+/* representing HT siblings of each logical CPU */
+cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
+
+/* representing HT and core siblings of each logical CPU */
+cpumask_t cpu_core_map[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(cpu_core_map);
/*
extern unsigned char trampoline_data[];
extern unsigned char trampoline_end[];
+/* State of each CPU */
+DEFINE_PER_CPU(int, cpu_state) = { 0 };
+
+/*
+ * Store all idle threads, this can be reused instead of creating
+ * a new thread. Also avoids complicated thread destroy functionality
+ * for idle threads.
+ */
+struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
+
+#define get_idle_for_cpu(x) (idle_thread_array[(x)])
+#define set_idle_for_cpu(x,p) (idle_thread_array[(x)] = (p))
+
/*
* Currently trivial. Write the real->protected mode
* bootstrap into the page concerned. The caller
{
unsigned long flags, i;
- if (smp_processor_id() != boot_cpu_id)
- return;
-
go[MASTER] = 0;
local_irq_save(flags);
return tcenter - best_tm;
}
-static __cpuinit void sync_tsc(void)
+static __cpuinit void sync_tsc(unsigned int master)
{
int i, done = 0;
long delta, adj, adjust_latency = 0;
unsigned long flags, rt, master_time_stamp, bound;
-#if DEBUG_TSC_SYNC
+#ifdef DEBUG_TSC_SYNC
static struct syncdebug {
long rt; /* roundtrip time */
long master; /* master's timestamp */
} t[NUM_ROUNDS] __cpuinitdata;
#endif
+ printk(KERN_INFO "CPU %d: Syncing TSC to CPU %u.\n",
+ smp_processor_id(), master);
+
go[MASTER] = 1;
- smp_call_function(sync_master, NULL, 1, 0);
+ /* It is dangerous to broadcast IPI as cpus are coming up,
+ * as they may not be ready to accept them. So since
+ * we only need to send the ipi to the boot cpu direct
+ * the message, and avoid the race.
+ */
+ smp_call_function_single(master, sync_master, NULL, 1, 0);
while (go[MASTER]) /* wait for master to be ready */
no_cpu_relax();
rdtscll(t);
wrmsrl(MSR_IA32_TSC, t + adj);
}
-#if DEBUG_TSC_SYNC
+#ifdef DEBUG_TSC_SYNC
t[i].rt = rt;
t[i].master = master_time_stamp;
t[i].diff = delta;
}
spin_unlock_irqrestore(&tsc_sync_lock, flags);
-#if DEBUG_TSC_SYNC
+#ifdef DEBUG_TSC_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);
printk(KERN_INFO
"CPU %d: synchronized TSC with CPU %u (last diff %ld cycles, "
"maxerr %lu cycles)\n",
- smp_processor_id(), boot_cpu_id, delta, rt);
+ smp_processor_id(), master, delta, rt);
}
static void __cpuinit tsc_sync_wait(void)
{
- if (notscsync || !cpu_has_tsc)
+ /*
+ * When the CPU has synchronized TSCs assume the BIOS
+ * or the hardware already synced. Otherwise we could
+ * mess up a possible perfect synchronization with a
+ * not-quite-perfect algorithm.
+ */
+ if (notscsync || !cpu_has_tsc || !unsynchronized_tsc())
return;
- printk(KERN_INFO "CPU %d: Syncing TSC to CPU %u.\n", smp_processor_id(),
- boot_cpu_id);
- sync_tsc();
+ sync_tsc(0);
}
static __init int notscsync_setup(char *s)
{
notscsync = 1;
- return 0;
+ return 1;
}
__setup("notscsync", notscsync_setup);
/*
* Get our bogomips.
+ *
+ * Need to enable IRQs because it can take longer and then
+ * the NMI watchdog might kill us.
*/
+ local_irq_enable();
calibrate_delay();
+ local_irq_disable();
Dprintk("Stack at about %p\n",&cpuid);
disable_APIC_timer();
cpu_set(cpuid, cpu_callin_map);
}
+/* maps the cpu to the sched domain representing multi-core */
+cpumask_t cpu_coregroup_map(int cpu)
+{
+ struct cpuinfo_x86 *c = cpu_data + cpu;
+ /*
+ * For perf, we return last level cache shared map.
+ * TBD: when power saving sched policy is added, we will return
+ * cpu_core_map when power saving policy is enabled
+ */
+ return c->llc_shared_map;
+}
+
+/* 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_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]);
+ cpu_set(i, c[cpu].llc_shared_map);
+ cpu_set(cpu, c[i].llc_shared_map);
+ }
+ }
+ } else {
+ cpu_set(cpu, cpu_sibling_map[cpu]);
+ }
+
+ cpu_set(cpu, c[cpu].llc_shared_map);
+
+ 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 (cpu_llc_id[cpu] != BAD_APICID &&
+ cpu_llc_id[cpu] == cpu_llc_id[i]) {
+ cpu_set(i, c[cpu].llc_shared_map);
+ cpu_set(cpu, c[i].llc_shared_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;
+ }
+ }
+}
+
/*
* Setup code on secondary processor (after comming out of the trampoline)
*/
* things done here to the most necessary things.
*/
cpu_init();
+ preempt_disable();
smp_callin();
/* otherwise gcc will move up the smp_processor_id before the cpu_init */
enable_APIC_timer();
+ /*
+ * The sibling maps must be set before turing the online map on for
+ * this cpu
+ */
+ set_cpu_sibling_map(smp_processor_id());
+
+ /*
+ * Wait for TSC sync to not schedule things before.
+ * We still process interrupts, which could see an inconsistent
+ * time in that window unfortunately.
+ * Do this here because TSC sync has global unprotected state.
+ */
+ tsc_sync_wait();
+
+ /*
+ * We need to hold call_lock, so there is no inconsistency
+ * between the time smp_call_function() determines number of
+ * IPI receipients, and the time when the determination is made
+ * for which cpus receive the IPI in genapic_flat.c. Holding this
+ * lock helps us to not include this cpu in a currently in progress
+ * smp_call_function().
+ */
+ lock_ipi_call_lock();
+
/*
* Allow the master to continue.
*/
cpu_set(smp_processor_id(), cpu_online_map);
- mb();
-
- /* Wait for TSC sync to not schedule things before.
- We still process interrupts, which could see an inconsistent
- time in that window unfortunately. */
- tsc_sync_wait();
+ per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
+ unlock_ipi_call_lock();
cpu_idle();
}
extern volatile unsigned long init_rsp;
extern void (*initial_code)(void);
-#if APIC_DEBUG
+#ifdef APIC_DEBUG
static void inquire_remote_apic(int apicid)
{
unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
*/
apic_wait_icr_idle();
- apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(apicid));
- apic_write_around(APIC_ICR, APIC_DM_REMRD | regs[i]);
+ apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(apicid));
+ apic_write(APIC_ICR, APIC_DM_REMRD | regs[i]);
timeout = 0;
do {
/*
* Turn INIT on target chip
*/
- apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
+ apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
/*
* Send IPI
*/
- apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_INT_ASSERT
+ apic_write(APIC_ICR, APIC_INT_LEVELTRIG | APIC_INT_ASSERT
| APIC_DM_INIT);
Dprintk("Waiting for send to finish...\n");
Dprintk("Deasserting INIT.\n");
/* Target chip */
- apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
+ apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
/* Send IPI */
- apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_DM_INIT);
+ apic_write(APIC_ICR, APIC_INT_LEVELTRIG | APIC_DM_INIT);
Dprintk("Waiting for send to finish...\n");
timeout = 0;
send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
} while (send_status && (timeout++ < 1000));
+ mb();
atomic_set(&init_deasserted, 1);
- /*
- * Should we send STARTUP IPIs ?
- *
- * Determine this based on the APIC version.
- * If we don't have an integrated APIC, don't send the STARTUP IPIs.
- */
- if (APIC_INTEGRATED(apic_version[phys_apicid]))
- num_starts = 2;
- else
- num_starts = 0;
+ num_starts = 2;
/*
* Run STARTUP IPI loop.
for (j = 1; j <= num_starts; j++) {
Dprintk("Sending STARTUP #%d.\n",j);
- apic_read_around(APIC_SPIV);
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
Dprintk("After apic_write.\n");
*/
/* Target chip */
- apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
+ apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
/* Boot on the stack */
/* Kick the second */
- apic_write_around(APIC_ICR, APIC_DM_STARTUP
- | (start_rip >> 12));
+ apic_write(APIC_ICR, APIC_DM_STARTUP | (start_rip >> 12));
/*
* Give the other CPU some time to accept the IPI.
* Due to the Pentium erratum 3AP.
*/
if (maxlvt > 3) {
- apic_read_around(APIC_SPIV);
apic_write(APIC_ESR, 0);
}
accept_status = (apic_read(APIC_ESR) & 0xEF);
return (send_status | accept_status);
}
+struct create_idle {
+ struct task_struct *idle;
+ struct completion done;
+ int cpu;
+};
+
+void do_fork_idle(void *_c_idle)
+{
+ struct create_idle *c_idle = _c_idle;
+
+ c_idle->idle = fork_idle(c_idle->cpu);
+ complete(&c_idle->done);
+}
+
/*
* Boot one CPU.
*/
static int __cpuinit do_boot_cpu(int cpu, int apicid)
{
- struct task_struct *idle;
unsigned long boot_error;
int timeout;
unsigned long start_rip;
+ struct create_idle c_idle = {
+ .cpu = cpu,
+ .done = COMPLETION_INITIALIZER(c_idle.done),
+ };
+ DECLARE_WORK(work, do_fork_idle, &c_idle);
+
+ /* allocate memory for gdts of secondary cpus. Hotplug is considered */
+ if (!cpu_gdt_descr[cpu].address &&
+ !(cpu_gdt_descr[cpu].address = get_zeroed_page(GFP_KERNEL))) {
+ printk(KERN_ERR "Failed to allocate GDT for CPU %d\n", cpu);
+ return -1;
+ }
+
+ /* Allocate node local memory for AP pdas */
+ if (cpu_pda(cpu) == &boot_cpu_pda[cpu]) {
+ struct x8664_pda *newpda, *pda;
+ int node = cpu_to_node(cpu);
+ pda = cpu_pda(cpu);
+ newpda = kmalloc_node(sizeof (struct x8664_pda), GFP_ATOMIC,
+ node);
+ if (newpda) {
+ memcpy(newpda, pda, sizeof (struct x8664_pda));
+ cpu_pda(cpu) = newpda;
+ } else
+ printk(KERN_ERR
+ "Could not allocate node local PDA for CPU %d on node %d\n",
+ cpu, node);
+ }
+
+
+ c_idle.idle = get_idle_for_cpu(cpu);
+
+ if (c_idle.idle) {
+ c_idle.idle->thread.rsp = (unsigned long) (((struct pt_regs *)
+ (THREAD_SIZE + task_stack_page(c_idle.idle))) - 1);
+ init_idle(c_idle.idle, cpu);
+ goto do_rest;
+ }
+
/*
- * We can't use kernel_thread since we must avoid to
- * reschedule the child.
+ * During cold boot process, keventd thread is not spun up yet.
+ * When we do cpu hot-add, we create idle threads on the fly, we should
+ * not acquire any attributes from the calling context. Hence the clean
+ * way to create kernel_threads() is to do that from keventd().
+ * We do the current_is_keventd() due to the fact that ACPI notifier
+ * was also queuing to keventd() and when the caller is already running
+ * in context of keventd(), we would end up with locking up the keventd
+ * thread.
*/
- idle = fork_idle(cpu);
- if (IS_ERR(idle)) {
+ if (!keventd_up() || current_is_keventd())
+ work.func(work.data);
+ else {
+ schedule_work(&work);
+ wait_for_completion(&c_idle.done);
+ }
+
+ if (IS_ERR(c_idle.idle)) {
printk("failed fork for CPU %d\n", cpu);
- return PTR_ERR(idle);
+ return PTR_ERR(c_idle.idle);
}
- cpu_pda[cpu].pcurrent = idle;
+ set_idle_for_cpu(cpu, c_idle.idle);
+
+do_rest:
+
+ cpu_pda(cpu)->pcurrent = c_idle.idle;
start_rip = setup_trampoline();
- init_rsp = idle->thread.rsp;
+ init_rsp = c_idle.idle->thread.rsp;
per_cpu(init_tss,cpu).rsp0 = init_rsp;
initial_code = start_secondary;
- clear_ti_thread_flag(idle->thread_info, TIF_FORK);
+ clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
- printk(KERN_INFO "Booting processor %d/%d rip %lx rsp %lx\n", cpu, apicid,
- start_rip, init_rsp);
+ printk(KERN_INFO "Booting processor %d/%d APIC 0x%x\n", cpu,
+ cpus_weight(cpu_present_map),
+ apicid);
/*
* This grunge runs the startup process for
/*
* Be paranoid about clearing APIC errors.
*/
- if (APIC_INTEGRATED(apic_version[apicid])) {
- apic_read_around(APIC_SPIV);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- }
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
/*
* Status is now clean
else
/* trampoline code not run */
printk("Not responding.\n");
-#if APIC_DEBUG
+#ifdef APIC_DEBUG
inquire_remote_apic(apicid);
#endif
}
if (boot_error) {
cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */
clear_bit(cpu, &cpu_initialized); /* was set by cpu_init() */
+ clear_node_cpumask(cpu); /* was set by numa_add_cpu */
cpu_clear(cpu, cpu_present_map);
cpu_clear(cpu, cpu_possible_map);
x86_cpu_to_apicid[cpu] = BAD_APICID;
cycles_t cacheflush_time;
unsigned long cache_decay_ticks;
-/*
- * Construct cpu_sibling_map[], so that we can tell the sibling CPU
- * on SMT systems efficiently.
- */
-static __cpuinit void detect_siblings(void)
-{
- int cpu;
-
- for (cpu = 0; cpu < NR_CPUS; cpu++) {
- cpus_clear(cpu_sibling_map[cpu]);
- cpus_clear(cpu_core_map[cpu]);
- }
-
- for_each_online_cpu (cpu) {
- struct cpuinfo_x86 *c = cpu_data + cpu;
- int siblings = 0;
- int i;
- if (smp_num_siblings > 1) {
- for_each_online_cpu (i) {
- if (cpu_core_id[cpu] == cpu_core_id[i]) {
- siblings++;
- cpu_set(i, cpu_sibling_map[cpu]);
- }
- }
- } else {
- siblings++;
- cpu_set(cpu, cpu_sibling_map[cpu]);
- }
-
- if (siblings != smp_num_siblings) {
- printk(KERN_WARNING
- "WARNING: %d siblings found for CPU%d, should be %d\n",
- siblings, cpu, smp_num_siblings);
- smp_num_siblings = siblings;
- }
- if (c->x86_num_cores > 1) {
- for_each_online_cpu(i) {
- if (phys_proc_id[cpu] == phys_proc_id[i])
- cpu_set(i, cpu_core_map[cpu]);
- }
- } else
- cpu_core_map[cpu] = cpu_sibling_map[cpu];
- }
-}
-
/*
* Cleanup possible dangling ends...
*/
* Reset trampoline flag
*/
*((volatile int *) phys_to_virt(0x467)) = 0;
-
-#ifndef CONFIG_HOTPLUG_CPU
- /*
- * Free pages reserved for SMP bootup.
- * When you add hotplug CPU support later remove this
- * Note there is more work to be done for later CPU bootup.
- */
-
- free_page((unsigned long) __va(PAGE_SIZE));
- free_page((unsigned long) __va(SMP_TRAMPOLINE_BASE));
-#endif
}
/*
*
* RED-PEN audit/test this more. I bet there is more state messed up here.
*/
-static __cpuinit void disable_smp(void)
+static __init void disable_smp(void)
{
cpu_present_map = cpumask_of_cpu(0);
cpu_possible_map = cpumask_of_cpu(0);
cpu_set(0, cpu_core_map[0]);
}
+#ifdef CONFIG_HOTPLUG_CPU
+
+int additional_cpus __initdata = -1;
+
/*
- * Handle user cpus=... parameter.
+ * cpu_possible_map should be static, it cannot change as cpu's
+ * are onlined, or offlined. The reason is per-cpu data-structures
+ * are allocated by some modules at init time, and dont expect to
+ * do this dynamically on cpu arrival/departure.
+ * cpu_present_map on the other hand can change dynamically.
+ * In case when cpu_hotplug is not compiled, then we resort to current
+ * behaviour, which is cpu_possible == cpu_present.
+ * - Ashok Raj
+ *
+ * Three ways to find out the number of additional hotplug CPUs:
+ * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
+ * - The user can overwrite it with additional_cpus=NUM
+ * - Otherwise don't reserve additional CPUs.
+ * We do this because additional CPUs waste a lot of memory.
+ * -AK
*/
-static __cpuinit void enforce_max_cpus(unsigned max_cpus)
+__init void prefill_possible_map(void)
{
- int i, k;
- k = 0;
- for (i = 0; i < NR_CPUS; i++) {
- if (!cpu_possible(i))
- continue;
- if (++k > max_cpus) {
- cpu_clear(i, cpu_possible_map);
- cpu_clear(i, cpu_present_map);
- }
+ int i;
+ int possible;
+
+ if (additional_cpus == -1) {
+ if (disabled_cpus > 0)
+ additional_cpus = disabled_cpus;
+ else
+ additional_cpus = 0;
+ }
+ possible = num_processors + additional_cpus;
+ if (possible > NR_CPUS)
+ possible = NR_CPUS;
+
+ if (possible == 0) { /* Could be SMP kernel on UP hw with broken BIOS */
+ possible = 1;
+ printk (KERN_DEBUG "BIOS never enumerated boot CPU, fixing.\n");
}
+
+ printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n",
+ possible,
+ max_t(int, possible - num_processors, 0));
+
+ for (i = 0; i < possible; i++)
+ cpu_set(i, cpu_possible_map);
}
+#endif
/*
* Various sanity checks.
*/
-static int __cpuinit smp_sanity_check(unsigned max_cpus)
+static int __init smp_sanity_check(unsigned max_cpus)
{
if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
printk("weird, boot CPU (#%d) not listed by the BIOS.\n",
/*
* If we couldn't find a local APIC, then get out of here now!
*/
- if (APIC_INTEGRATED(apic_version[boot_cpu_id]) && !cpu_has_apic) {
+ if (!cpu_has_apic) {
printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
boot_cpu_id);
printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
* Prepare for SMP bootup. The MP table or ACPI has been read
* earlier. Just do some sanity checking here and enable APIC mode.
*/
-void __cpuinit smp_prepare_cpus(unsigned int max_cpus)
+void __init smp_prepare_cpus(unsigned int max_cpus)
{
- int i;
-
nmi_watchdog_default();
current_cpu_data = boot_cpu_data;
current_thread_info()->cpu = 0; /* needed? */
-
- enforce_max_cpus(max_cpus);
-
- /*
- * Fill in cpu_present_mask
- */
- for (i = 0; i < NR_CPUS; i++) {
- int apicid = cpu_present_to_apicid(i);
- if (physid_isset(apicid, phys_cpu_present_map)) {
- cpu_set(i, cpu_present_map);
- /* possible map would be different if we supported real
- CPU hotplug. */
- cpu_set(i, cpu_possible_map);
- }
- }
+ set_cpu_sibling_map(0);
if (smp_sanity_check(max_cpus) < 0) {
printk(KERN_INFO "SMP disabled\n");
int me = smp_processor_id();
cpu_set(me, cpu_online_map);
cpu_set(me, cpu_callout_map);
+ per_cpu(cpu_state, me) = CPU_ONLINE;
}
/*
* Entry point to boot a CPU.
- *
- * This is all __cpuinit, not __devinit for now because we don't support
- * CPU hotplug (yet).
*/
int __cpuinit __cpu_up(unsigned int cpu)
{
return -EINVAL;
}
+ /*
+ * Already booted CPU?
+ */
+ if (cpu_isset(cpu, cpu_callin_map)) {
+ Dprintk("do_boot_cpu %d Already started\n", cpu);
+ return -ENOSYS;
+ }
+
+ per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
/* Boot it! */
err = do_boot_cpu(cpu, apicid);
if (err < 0) {
while (!cpu_isset(cpu, cpu_online_map))
cpu_relax();
- return 0;
+ err = 0;
+
+ return err;
}
/*
* Finish the SMP boot.
*/
-void __cpuinit smp_cpus_done(unsigned int max_cpus)
+void __init smp_cpus_done(unsigned int max_cpus)
{
- zap_low_mappings();
smp_cleanup_boot();
#ifdef CONFIG_X86_IO_APIC
setup_ioapic_dest();
#endif
- detect_siblings();
- time_init_gtod();
-
check_nmi_watchdog();
}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+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]);
+ 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)
+{
+ int cpu = smp_processor_id();
+
+ cpu_clear(cpu, cpu_callout_map);
+ cpu_clear(cpu, cpu_callin_map);
+ clear_bit(cpu, &cpu_initialized); /* was set by cpu_init() */
+ clear_node_cpumask(cpu);
+}
+
+int __cpu_disable(void)
+{
+ int cpu = smp_processor_id();
+
+ /*
+ * Perhaps use cpufreq to drop frequency, but that could go
+ * into generic code.
+ *
+ * We won't take down the boot processor on i386 due to some
+ * interrupts only being able to be serviced by the BSP.
+ * Especially so if we're not using an IOAPIC -zwane
+ */
+ if (cpu == 0)
+ return -EBUSY;
+
+ clear_local_APIC();
+
+ /*
+ * HACK:
+ * Allow any queued timer interrupts to get serviced
+ * This is only a temporary solution until we cleanup
+ * fixup_irqs as we do for IA64.
+ */
+ local_irq_enable();
+ mdelay(1);
+
+ local_irq_disable();
+ remove_siblinginfo(cpu);
+
+ /* It's now safe to remove this processor from the online map */
+ cpu_clear(cpu, cpu_online_map);
+ remove_cpu_from_maps();
+ fixup_irqs(cpu_online_map);
+ return 0;
+}
+
+void __cpu_die(unsigned int cpu)
+{
+ /* We don't do anything here: idle task is faking death itself. */
+ unsigned int i;
+
+ for (i = 0; i < 10; 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);
+}
+
+__init int setup_additional_cpus(char *s)
+{
+ return get_option(&s, &additional_cpus);
+}
+__setup("additional_cpus=", setup_additional_cpus);
+
+#else /* ... !CONFIG_HOTPLUG_CPU */
+
+int __cpu_disable(void)
+{
+ return -ENOSYS;
+}
+
+void __cpu_die(unsigned int cpu)
+{
+ /* We said "no" in __cpu_disable */
+ BUG();
+}
+#endif /* CONFIG_HOTPLUG_CPU */