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Diffstat (limited to 'arch/x86/kernel/cpu/resctrl/core.c')
-rw-r--r--arch/x86/kernel/cpu/resctrl/core.c111
1 files changed, 52 insertions, 59 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 19e0681f0435..83e40341583e 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -16,6 +16,7 @@
#define pr_fmt(fmt) "resctrl: " fmt
+#include <linux/cpu.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/cacheinfo.h>
@@ -25,8 +26,15 @@
#include <asm/resctrl.h>
#include "internal.h"
-/* Mutex to protect rdtgroup access. */
-DEFINE_MUTEX(rdtgroup_mutex);
+/*
+ * rdt_domain structures are kfree()d when their last CPU goes offline,
+ * and allocated when the first CPU in a new domain comes online.
+ * The rdt_resource's domain list is updated when this happens. Readers of
+ * the domain list must either take cpus_read_lock(), or rely on an RCU
+ * read-side critical section, to avoid observing concurrent modification.
+ * All writers take this mutex:
+ */
+static DEFINE_MUTEX(domain_list_lock);
/*
* The cached resctrl_pqr_state is strictly per CPU and can never be
@@ -136,15 +144,15 @@ static inline void cache_alloc_hsw_probe(void)
{
struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_L3];
struct rdt_resource *r = &hw_res->r_resctrl;
- u32 l, h, max_cbm = BIT_MASK(20) - 1;
+ u64 max_cbm = BIT_ULL_MASK(20) - 1, l3_cbm_0;
- if (wrmsr_safe(MSR_IA32_L3_CBM_BASE, max_cbm, 0))
+ if (wrmsrl_safe(MSR_IA32_L3_CBM_BASE, max_cbm))
return;
- rdmsr(MSR_IA32_L3_CBM_BASE, l, h);
+ rdmsrl(MSR_IA32_L3_CBM_BASE, l3_cbm_0);
/* If all the bits were set in MSR, return success */
- if (l != max_cbm)
+ if (l3_cbm_0 != max_cbm)
return;
hw_res->num_closid = 4;
@@ -231,9 +239,7 @@ static bool __get_mem_config_intel(struct rdt_resource *r)
static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
{
struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
- union cpuid_0x10_3_eax eax;
- union cpuid_0x10_x_edx edx;
- u32 ebx, ecx, subleaf;
+ u32 eax, ebx, ecx, edx, subleaf;
/*
* Query CPUID_Fn80000020_EDX_x01 for MBA and
@@ -241,9 +247,9 @@ static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
*/
subleaf = (r->rid == RDT_RESOURCE_SMBA) ? 2 : 1;
- cpuid_count(0x80000020, subleaf, &eax.full, &ebx, &ecx, &edx.full);
- hw_res->num_closid = edx.split.cos_max + 1;
- r->default_ctrl = MAX_MBA_BW_AMD;
+ cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
+ hw_res->num_closid = edx + 1;
+ r->default_ctrl = 1 << eax;
/* AMD does not use delay */
r->membw.delay_linear = false;
@@ -512,6 +518,8 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
struct rdt_domain *d;
int err;
+ lockdep_assert_held(&domain_list_lock);
+
d = rdt_find_domain(r, id, &add_pos);
if (IS_ERR(d)) {
pr_warn("Couldn't find cache id for CPU %d\n", cpu);
@@ -545,11 +553,12 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)
return;
}
- list_add_tail(&d->list, add_pos);
+ list_add_tail_rcu(&d->list, add_pos);
err = resctrl_online_domain(r, d);
if (err) {
- list_del(&d->list);
+ list_del_rcu(&d->list);
+ synchronize_rcu();
domain_free(hw_dom);
}
}
@@ -560,6 +569,8 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
struct rdt_hw_domain *hw_dom;
struct rdt_domain *d;
+ lockdep_assert_held(&domain_list_lock);
+
d = rdt_find_domain(r, id, NULL);
if (IS_ERR_OR_NULL(d)) {
pr_warn("Couldn't find cache id for CPU %d\n", cpu);
@@ -570,7 +581,8 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
cpumask_clear_cpu(cpu, &d->cpu_mask);
if (cpumask_empty(&d->cpu_mask)) {
resctrl_offline_domain(r, d);
- list_del(&d->list);
+ list_del_rcu(&d->list);
+ synchronize_rcu();
/*
* rdt_domain "d" is going to be freed below, so clear
@@ -582,73 +594,47 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
return;
}
-
- if (r == &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl) {
- if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
- cancel_delayed_work(&d->mbm_over);
- mbm_setup_overflow_handler(d, 0);
- }
- if (is_llc_occupancy_enabled() && cpu == d->cqm_work_cpu &&
- has_busy_rmid(r, d)) {
- cancel_delayed_work(&d->cqm_limbo);
- cqm_setup_limbo_handler(d, 0);
- }
- }
}
static void clear_closid_rmid(int cpu)
{
struct resctrl_pqr_state *state = this_cpu_ptr(&pqr_state);
- state->default_closid = 0;
- state->default_rmid = 0;
- state->cur_closid = 0;
- state->cur_rmid = 0;
- wrmsr(MSR_IA32_PQR_ASSOC, 0, 0);
+ state->default_closid = RESCTRL_RESERVED_CLOSID;
+ state->default_rmid = RESCTRL_RESERVED_RMID;
+ state->cur_closid = RESCTRL_RESERVED_CLOSID;
+ state->cur_rmid = RESCTRL_RESERVED_RMID;
+ wrmsr(MSR_IA32_PQR_ASSOC, RESCTRL_RESERVED_RMID,
+ RESCTRL_RESERVED_CLOSID);
}
-static int resctrl_online_cpu(unsigned int cpu)
+static int resctrl_arch_online_cpu(unsigned int cpu)
{
struct rdt_resource *r;
- mutex_lock(&rdtgroup_mutex);
+ mutex_lock(&domain_list_lock);
for_each_capable_rdt_resource(r)
domain_add_cpu(cpu, r);
- /* The cpu is set in default rdtgroup after online. */
- cpumask_set_cpu(cpu, &rdtgroup_default.cpu_mask);
+ mutex_unlock(&domain_list_lock);
+
clear_closid_rmid(cpu);
- mutex_unlock(&rdtgroup_mutex);
+ resctrl_online_cpu(cpu);
return 0;
}
-static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
-{
- struct rdtgroup *cr;
-
- list_for_each_entry(cr, &r->mon.crdtgrp_list, mon.crdtgrp_list) {
- if (cpumask_test_and_clear_cpu(cpu, &cr->cpu_mask)) {
- break;
- }
- }
-}
-
-static int resctrl_offline_cpu(unsigned int cpu)
+static int resctrl_arch_offline_cpu(unsigned int cpu)
{
- struct rdtgroup *rdtgrp;
struct rdt_resource *r;
- mutex_lock(&rdtgroup_mutex);
+ resctrl_offline_cpu(cpu);
+
+ mutex_lock(&domain_list_lock);
for_each_capable_rdt_resource(r)
domain_remove_cpu(cpu, r);
- list_for_each_entry(rdtgrp, &rdt_all_groups, rdtgroup_list) {
- if (cpumask_test_and_clear_cpu(cpu, &rdtgrp->cpu_mask)) {
- clear_childcpus(rdtgrp, cpu);
- break;
- }
- }
+ mutex_unlock(&domain_list_lock);
+
clear_closid_rmid(cpu);
- mutex_unlock(&rdtgroup_mutex);
return 0;
}
@@ -968,7 +954,8 @@ static int __init resctrl_late_init(void)
state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
"x86/resctrl/cat:online:",
- resctrl_online_cpu, resctrl_offline_cpu);
+ resctrl_arch_online_cpu,
+ resctrl_arch_offline_cpu);
if (state < 0)
return state;
@@ -992,8 +979,14 @@ late_initcall(resctrl_late_init);
static void __exit resctrl_exit(void)
{
+ struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+
cpuhp_remove_state(rdt_online);
+
rdtgroup_exit();
+
+ if (r->mon_capable)
+ rdt_put_mon_l3_config();
}
__exitcall(resctrl_exit);
generated by cgit v1.2.3-70-g09d2 (git 2.48.1) at 2025-05-23 17:09:39 +0000