280 lines
7.3 KiB
C
280 lines
7.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
|
|
#include <linux/cpuhotplug.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mm.h>
|
|
|
|
#include <asm/apic.h>
|
|
|
|
#include "local.h"
|
|
|
|
#define apic_cluster(apicid) ((apicid) >> 4)
|
|
|
|
/*
|
|
* __x2apic_send_IPI_mask() possibly needs to read
|
|
* x86_cpu_to_logical_apicid for all online cpus in a sequential way.
|
|
* Using per cpu variable would cost one cache line per cpu.
|
|
*/
|
|
static u32 *x86_cpu_to_logical_apicid __read_mostly;
|
|
|
|
static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
|
|
static DEFINE_PER_CPU_READ_MOSTLY(struct cpumask *, cluster_masks);
|
|
|
|
static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
|
|
{
|
|
return x2apic_enabled();
|
|
}
|
|
|
|
static void x2apic_send_IPI(int cpu, int vector)
|
|
{
|
|
u32 dest = x86_cpu_to_logical_apicid[cpu];
|
|
|
|
/* x2apic MSRs are special and need a special fence: */
|
|
weak_wrmsr_fence();
|
|
__x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
|
|
}
|
|
|
|
static void
|
|
__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
|
|
{
|
|
unsigned int cpu, clustercpu;
|
|
struct cpumask *tmpmsk;
|
|
unsigned long flags;
|
|
u32 dest;
|
|
|
|
/* x2apic MSRs are special and need a special fence: */
|
|
weak_wrmsr_fence();
|
|
local_irq_save(flags);
|
|
|
|
tmpmsk = this_cpu_cpumask_var_ptr(ipi_mask);
|
|
cpumask_copy(tmpmsk, mask);
|
|
/* If IPI should not be sent to self, clear current CPU */
|
|
if (apic_dest != APIC_DEST_ALLINC)
|
|
__cpumask_clear_cpu(smp_processor_id(), tmpmsk);
|
|
|
|
/* Collapse cpus in a cluster so a single IPI per cluster is sent */
|
|
for_each_cpu(cpu, tmpmsk) {
|
|
struct cpumask *cmsk = per_cpu(cluster_masks, cpu);
|
|
|
|
dest = 0;
|
|
for_each_cpu_and(clustercpu, tmpmsk, cmsk)
|
|
dest |= x86_cpu_to_logical_apicid[clustercpu];
|
|
|
|
if (!dest)
|
|
continue;
|
|
|
|
__x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
|
|
/* Remove cluster CPUs from tmpmask */
|
|
cpumask_andnot(tmpmsk, tmpmsk, cmsk);
|
|
}
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
|
|
{
|
|
__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
|
|
}
|
|
|
|
static void
|
|
x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
|
|
{
|
|
__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
|
|
}
|
|
|
|
static void x2apic_send_IPI_allbutself(int vector)
|
|
{
|
|
__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
|
|
}
|
|
|
|
static void x2apic_send_IPI_all(int vector)
|
|
{
|
|
__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
|
|
}
|
|
|
|
static u32 x2apic_calc_apicid(unsigned int cpu)
|
|
{
|
|
return x86_cpu_to_logical_apicid[cpu];
|
|
}
|
|
|
|
static void init_x2apic_ldr(void)
|
|
{
|
|
struct cpumask *cmsk = this_cpu_read(cluster_masks);
|
|
|
|
BUG_ON(!cmsk);
|
|
|
|
cpumask_set_cpu(smp_processor_id(), cmsk);
|
|
}
|
|
|
|
/*
|
|
* As an optimisation during boot, set the cluster_mask for all present
|
|
* CPUs at once, to prevent each of them having to iterate over the others
|
|
* to find the existing cluster_mask.
|
|
*/
|
|
static void prefill_clustermask(struct cpumask *cmsk, unsigned int cpu, u32 cluster)
|
|
{
|
|
int cpu_i;
|
|
|
|
for_each_present_cpu(cpu_i) {
|
|
struct cpumask **cpu_cmsk = &per_cpu(cluster_masks, cpu_i);
|
|
u32 apicid = apic->cpu_present_to_apicid(cpu_i);
|
|
|
|
if (apicid == BAD_APICID || cpu_i == cpu || apic_cluster(apicid) != cluster)
|
|
continue;
|
|
|
|
if (WARN_ON_ONCE(*cpu_cmsk == cmsk))
|
|
continue;
|
|
|
|
BUG_ON(*cpu_cmsk);
|
|
*cpu_cmsk = cmsk;
|
|
}
|
|
}
|
|
|
|
static int alloc_clustermask(unsigned int cpu, u32 cluster, int node)
|
|
{
|
|
struct cpumask *cmsk = NULL;
|
|
unsigned int cpu_i;
|
|
|
|
/*
|
|
* At boot time, the CPU present mask is stable. The cluster mask is
|
|
* allocated for the first CPU in the cluster and propagated to all
|
|
* present siblings in the cluster. If the cluster mask is already set
|
|
* on entry to this function for a given CPU, there is nothing to do.
|
|
*/
|
|
if (per_cpu(cluster_masks, cpu))
|
|
return 0;
|
|
|
|
if (system_state < SYSTEM_RUNNING)
|
|
goto alloc;
|
|
|
|
/*
|
|
* On post boot hotplug for a CPU which was not present at boot time,
|
|
* iterate over all possible CPUs (even those which are not present
|
|
* any more) to find any existing cluster mask.
|
|
*/
|
|
for_each_possible_cpu(cpu_i) {
|
|
u32 apicid = apic->cpu_present_to_apicid(cpu_i);
|
|
|
|
if (apicid != BAD_APICID && apic_cluster(apicid) == cluster) {
|
|
cmsk = per_cpu(cluster_masks, cpu_i);
|
|
/*
|
|
* If the cluster is already initialized, just store
|
|
* the mask and return. There's no need to propagate.
|
|
*/
|
|
if (cmsk) {
|
|
per_cpu(cluster_masks, cpu) = cmsk;
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
/*
|
|
* No CPU in the cluster has ever been initialized, so fall through to
|
|
* the boot time code which will also populate the cluster mask for any
|
|
* other CPU in the cluster which is (now) present.
|
|
*/
|
|
alloc:
|
|
cmsk = kzalloc_node(sizeof(*cmsk), GFP_KERNEL, node);
|
|
if (!cmsk)
|
|
return -ENOMEM;
|
|
per_cpu(cluster_masks, cpu) = cmsk;
|
|
prefill_clustermask(cmsk, cpu, cluster);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int x2apic_prepare_cpu(unsigned int cpu)
|
|
{
|
|
u32 phys_apicid = apic->cpu_present_to_apicid(cpu);
|
|
u32 cluster = apic_cluster(phys_apicid);
|
|
u32 logical_apicid = (cluster << 16) | (1 << (phys_apicid & 0xf));
|
|
|
|
x86_cpu_to_logical_apicid[cpu] = logical_apicid;
|
|
|
|
if (alloc_clustermask(cpu, cluster, cpu_to_node(cpu)) < 0)
|
|
return -ENOMEM;
|
|
if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL))
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
static int x2apic_dead_cpu(unsigned int dead_cpu)
|
|
{
|
|
struct cpumask *cmsk = per_cpu(cluster_masks, dead_cpu);
|
|
|
|
if (cmsk)
|
|
cpumask_clear_cpu(dead_cpu, cmsk);
|
|
free_cpumask_var(per_cpu(ipi_mask, dead_cpu));
|
|
return 0;
|
|
}
|
|
|
|
static int x2apic_cluster_probe(void)
|
|
{
|
|
u32 slots;
|
|
|
|
if (!x2apic_mode)
|
|
return 0;
|
|
|
|
slots = max_t(u32, L1_CACHE_BYTES/sizeof(u32), nr_cpu_ids);
|
|
x86_cpu_to_logical_apicid = kcalloc(slots, sizeof(u32), GFP_KERNEL);
|
|
if (!x86_cpu_to_logical_apicid)
|
|
return 0;
|
|
|
|
if (cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "x86/x2apic:prepare",
|
|
x2apic_prepare_cpu, x2apic_dead_cpu) < 0) {
|
|
pr_err("Failed to register X2APIC_PREPARE\n");
|
|
kfree(x86_cpu_to_logical_apicid);
|
|
x86_cpu_to_logical_apicid = NULL;
|
|
return 0;
|
|
}
|
|
init_x2apic_ldr();
|
|
return 1;
|
|
}
|
|
|
|
static struct apic apic_x2apic_cluster __ro_after_init = {
|
|
|
|
.name = "cluster x2apic",
|
|
.probe = x2apic_cluster_probe,
|
|
.acpi_madt_oem_check = x2apic_acpi_madt_oem_check,
|
|
.apic_id_valid = x2apic_apic_id_valid,
|
|
.apic_id_registered = x2apic_apic_id_registered,
|
|
|
|
.delivery_mode = APIC_DELIVERY_MODE_FIXED,
|
|
.dest_mode_logical = true,
|
|
|
|
.disable_esr = 0,
|
|
|
|
.check_apicid_used = NULL,
|
|
.init_apic_ldr = init_x2apic_ldr,
|
|
.ioapic_phys_id_map = NULL,
|
|
.setup_apic_routing = NULL,
|
|
.cpu_present_to_apicid = default_cpu_present_to_apicid,
|
|
.apicid_to_cpu_present = NULL,
|
|
.check_phys_apicid_present = default_check_phys_apicid_present,
|
|
.phys_pkg_id = x2apic_phys_pkg_id,
|
|
|
|
.get_apic_id = x2apic_get_apic_id,
|
|
.set_apic_id = x2apic_set_apic_id,
|
|
|
|
.calc_dest_apicid = x2apic_calc_apicid,
|
|
|
|
.send_IPI = x2apic_send_IPI,
|
|
.send_IPI_mask = x2apic_send_IPI_mask,
|
|
.send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
|
|
.send_IPI_allbutself = x2apic_send_IPI_allbutself,
|
|
.send_IPI_all = x2apic_send_IPI_all,
|
|
.send_IPI_self = x2apic_send_IPI_self,
|
|
|
|
.inquire_remote_apic = NULL,
|
|
|
|
.read = native_apic_msr_read,
|
|
.write = native_apic_msr_write,
|
|
.eoi_write = native_apic_msr_eoi_write,
|
|
.icr_read = native_x2apic_icr_read,
|
|
.icr_write = native_x2apic_icr_write,
|
|
.wait_icr_idle = native_x2apic_wait_icr_idle,
|
|
.safe_wait_icr_idle = native_safe_x2apic_wait_icr_idle,
|
|
};
|
|
|
|
apic_driver(apic_x2apic_cluster);
|