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-rw-r--r--kernel/sched/isolation.c191
1 files changed, 125 insertions, 66 deletions
diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index 008d6ac2342b..373d42c707bc 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -7,140 +7,182 @@
* Copyright (C) 2017-2018 SUSE, Frederic Weisbecker
*
*/
-#include "sched.h"
+
+enum hk_flags {
+ HK_FLAG_TIMER = BIT(HK_TYPE_TIMER),
+ HK_FLAG_RCU = BIT(HK_TYPE_RCU),
+ HK_FLAG_MISC = BIT(HK_TYPE_MISC),
+ HK_FLAG_SCHED = BIT(HK_TYPE_SCHED),
+ HK_FLAG_TICK = BIT(HK_TYPE_TICK),
+ HK_FLAG_DOMAIN = BIT(HK_TYPE_DOMAIN),
+ HK_FLAG_WQ = BIT(HK_TYPE_WQ),
+ HK_FLAG_MANAGED_IRQ = BIT(HK_TYPE_MANAGED_IRQ),
+ HK_FLAG_KTHREAD = BIT(HK_TYPE_KTHREAD),
+};
DEFINE_STATIC_KEY_FALSE(housekeeping_overridden);
EXPORT_SYMBOL_GPL(housekeeping_overridden);
-static cpumask_var_t housekeeping_mask;
-static unsigned int housekeeping_flags;
-bool housekeeping_enabled(enum hk_flags flags)
+struct housekeeping {
+ cpumask_var_t cpumasks[HK_TYPE_MAX];
+ unsigned long flags;
+};
+
+static struct housekeeping housekeeping;
+
+bool housekeeping_enabled(enum hk_type type)
{
- return !!(housekeeping_flags & flags);
+ return !!(housekeeping.flags & BIT(type));
}
EXPORT_SYMBOL_GPL(housekeeping_enabled);
-int housekeeping_any_cpu(enum hk_flags flags)
+int housekeeping_any_cpu(enum hk_type type)
{
int cpu;
if (static_branch_unlikely(&housekeeping_overridden)) {
- if (housekeeping_flags & flags) {
- cpu = sched_numa_find_closest(housekeeping_mask, smp_processor_id());
+ if (housekeeping.flags & BIT(type)) {
+ cpu = sched_numa_find_closest(housekeeping.cpumasks[type], smp_processor_id());
if (cpu < nr_cpu_ids)
return cpu;
- return cpumask_any_and(housekeeping_mask, cpu_online_mask);
+ return cpumask_any_and(housekeeping.cpumasks[type], cpu_online_mask);
}
}
return smp_processor_id();
}
EXPORT_SYMBOL_GPL(housekeeping_any_cpu);
-const struct cpumask *housekeeping_cpumask(enum hk_flags flags)
+const struct cpumask *housekeeping_cpumask(enum hk_type type)
{
if (static_branch_unlikely(&housekeeping_overridden))
- if (housekeeping_flags & flags)
- return housekeeping_mask;
+ if (housekeeping.flags & BIT(type))
+ return housekeeping.cpumasks[type];
return cpu_possible_mask;
}
EXPORT_SYMBOL_GPL(housekeeping_cpumask);
-void housekeeping_affine(struct task_struct *t, enum hk_flags flags)
+void housekeeping_affine(struct task_struct *t, enum hk_type type)
{
if (static_branch_unlikely(&housekeeping_overridden))
- if (housekeeping_flags & flags)
- set_cpus_allowed_ptr(t, housekeeping_mask);
+ if (housekeeping.flags & BIT(type))
+ set_cpus_allowed_ptr(t, housekeeping.cpumasks[type]);
}
EXPORT_SYMBOL_GPL(housekeeping_affine);
-bool housekeeping_test_cpu(int cpu, enum hk_flags flags)
+bool housekeeping_test_cpu(int cpu, enum hk_type type)
{
if (static_branch_unlikely(&housekeeping_overridden))
- if (housekeeping_flags & flags)
- return cpumask_test_cpu(cpu, housekeeping_mask);
+ if (housekeeping.flags & BIT(type))
+ return cpumask_test_cpu(cpu, housekeeping.cpumasks[type]);
return true;
}
EXPORT_SYMBOL_GPL(housekeeping_test_cpu);
void __init housekeeping_init(void)
{
- if (!housekeeping_flags)
+ enum hk_type type;
+
+ if (!housekeeping.flags)
return;
static_branch_enable(&housekeeping_overridden);
- if (housekeeping_flags & HK_FLAG_TICK)
+ if (housekeeping.flags & HK_FLAG_TICK)
sched_tick_offload_init();
- /* We need at least one CPU to handle housekeeping work */
- WARN_ON_ONCE(cpumask_empty(housekeeping_mask));
+ for_each_set_bit(type, &housekeeping.flags, HK_TYPE_MAX) {
+ /* We need at least one CPU to handle housekeeping work */
+ WARN_ON_ONCE(cpumask_empty(housekeeping.cpumasks[type]));
+ }
+}
+
+static void __init housekeeping_setup_type(enum hk_type type,
+ cpumask_var_t housekeeping_staging)
+{
+
+ alloc_bootmem_cpumask_var(&housekeeping.cpumasks[type]);
+ cpumask_copy(housekeeping.cpumasks[type],
+ housekeeping_staging);
}
-static int __init housekeeping_setup(char *str, enum hk_flags flags)
+static int __init housekeeping_setup(char *str, unsigned long flags)
{
- cpumask_var_t non_housekeeping_mask;
- cpumask_var_t tmp;
- int err;
+ cpumask_var_t non_housekeeping_mask, housekeeping_staging;
+ int err = 0;
+
+ if ((flags & HK_FLAG_TICK) && !(housekeeping.flags & HK_FLAG_TICK)) {
+ if (!IS_ENABLED(CONFIG_NO_HZ_FULL)) {
+ pr_warn("Housekeeping: nohz unsupported."
+ " Build with CONFIG_NO_HZ_FULL\n");
+ return 0;
+ }
+ }
alloc_bootmem_cpumask_var(&non_housekeeping_mask);
- err = cpulist_parse(str, non_housekeeping_mask);
- if (err < 0 || cpumask_last(non_housekeeping_mask) >= nr_cpu_ids) {
+ if (cpulist_parse(str, non_housekeeping_mask) < 0) {
pr_warn("Housekeeping: nohz_full= or isolcpus= incorrect CPU range\n");
- free_bootmem_cpumask_var(non_housekeeping_mask);
- return 0;
+ goto free_non_housekeeping_mask;
}
- alloc_bootmem_cpumask_var(&tmp);
- if (!housekeeping_flags) {
- alloc_bootmem_cpumask_var(&housekeeping_mask);
- cpumask_andnot(housekeeping_mask,
- cpu_possible_mask, non_housekeeping_mask);
+ alloc_bootmem_cpumask_var(&housekeeping_staging);
+ cpumask_andnot(housekeeping_staging,
+ cpu_possible_mask, non_housekeeping_mask);
- cpumask_andnot(tmp, cpu_present_mask, non_housekeeping_mask);
- if (cpumask_empty(tmp)) {
+ if (!cpumask_intersects(cpu_present_mask, housekeeping_staging)) {
+ __cpumask_set_cpu(smp_processor_id(), housekeeping_staging);
+ __cpumask_clear_cpu(smp_processor_id(), non_housekeeping_mask);
+ if (!housekeeping.flags) {
pr_warn("Housekeeping: must include one present CPU, "
"using boot CPU:%d\n", smp_processor_id());
- __cpumask_set_cpu(smp_processor_id(), housekeeping_mask);
- __cpumask_clear_cpu(smp_processor_id(), non_housekeeping_mask);
- }
- } else {
- cpumask_andnot(tmp, cpu_present_mask, non_housekeeping_mask);
- if (cpumask_empty(tmp))
- __cpumask_clear_cpu(smp_processor_id(), non_housekeeping_mask);
- cpumask_andnot(tmp, cpu_possible_mask, non_housekeeping_mask);
- if (!cpumask_equal(tmp, housekeeping_mask)) {
- pr_warn("Housekeeping: nohz_full= must match isolcpus=\n");
- free_bootmem_cpumask_var(tmp);
- free_bootmem_cpumask_var(non_housekeeping_mask);
- return 0;
}
}
- free_bootmem_cpumask_var(tmp);
- if ((flags & HK_FLAG_TICK) && !(housekeeping_flags & HK_FLAG_TICK)) {
- if (IS_ENABLED(CONFIG_NO_HZ_FULL)) {
- tick_nohz_full_setup(non_housekeeping_mask);
- } else {
- pr_warn("Housekeeping: nohz unsupported."
- " Build with CONFIG_NO_HZ_FULL\n");
- free_bootmem_cpumask_var(non_housekeeping_mask);
- return 0;
+ if (!housekeeping.flags) {
+ /* First setup call ("nohz_full=" or "isolcpus=") */
+ enum hk_type type;
+
+ for_each_set_bit(type, &flags, HK_TYPE_MAX)
+ housekeeping_setup_type(type, housekeeping_staging);
+ } else {
+ /* Second setup call ("nohz_full=" after "isolcpus=" or the reverse) */
+ enum hk_type type;
+ unsigned long iter_flags = flags & housekeeping.flags;
+
+ for_each_set_bit(type, &iter_flags, HK_TYPE_MAX) {
+ if (!cpumask_equal(housekeeping_staging,
+ housekeeping.cpumasks[type])) {
+ pr_warn("Housekeeping: nohz_full= must match isolcpus=\n");
+ goto free_housekeeping_staging;
+ }
}
+
+ iter_flags = flags & ~housekeeping.flags;
+
+ for_each_set_bit(type, &iter_flags, HK_TYPE_MAX)
+ housekeeping_setup_type(type, housekeeping_staging);
}
- housekeeping_flags |= flags;
+ if ((flags & HK_FLAG_TICK) && !(housekeeping.flags & HK_FLAG_TICK))
+ tick_nohz_full_setup(non_housekeeping_mask);
+
+ housekeeping.flags |= flags;
+ err = 1;
+free_housekeeping_staging:
+ free_bootmem_cpumask_var(housekeeping_staging);
+free_non_housekeeping_mask:
free_bootmem_cpumask_var(non_housekeeping_mask);
- return 1;
+ return err;
}
static int __init housekeeping_nohz_full_setup(char *str)
{
- unsigned int flags;
+ unsigned long flags;
- flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU | HK_FLAG_MISC;
+ flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU |
+ HK_FLAG_MISC | HK_FLAG_KTHREAD;
return housekeeping_setup(str, flags);
}
@@ -148,7 +190,10 @@ __setup("nohz_full=", housekeeping_nohz_full_setup);
static int __init housekeeping_isolcpus_setup(char *str)
{
- unsigned int flags = 0;
+ unsigned long flags = 0;
+ bool illegal = false;
+ char *par;
+ int len;
while (isalpha(*str)) {
if (!strncmp(str, "nohz,", 5)) {
@@ -169,8 +214,22 @@ static int __init housekeeping_isolcpus_setup(char *str)
continue;
}
- pr_warn("isolcpus: Error, unknown flag\n");
- return 0;
+ /*
+ * Skip unknown sub-parameter and validate that it is not
+ * containing an invalid character.
+ */
+ for (par = str, len = 0; *str && *str != ','; str++, len++) {
+ if (!isalpha(*str) && *str != '_')
+ illegal = true;
+ }
+
+ if (illegal) {
+ pr_warn("isolcpus: Invalid flag %.*s\n", len, par);
+ return 0;
+ }
+
+ pr_info("isolcpus: Skipped unknown flag %.*s\n", len, par);
+ str++;
}
/* Default behaviour for isolcpus without flags */