diff options
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 65 |
1 files changed, 38 insertions, 27 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 5797c2a7a93f..bbad5e375d3b 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -35,6 +35,7 @@ #include <linux/percpu-rwsem.h> #include <linux/cpuset.h> #include <linux/random.h> +#include <linux/cc_platform.h> #include <trace/events/power.h> #define CREATE_TRACE_POINTS @@ -71,7 +72,6 @@ struct cpuhp_cpu_state { bool rollback; bool single; bool bringup; - int cpu; struct hlist_node *node; struct hlist_node *last; enum cpuhp_state cb_state; @@ -475,7 +475,7 @@ static inline bool cpu_smt_allowed(unsigned int cpu) { return true; } #endif static inline enum cpuhp_state -cpuhp_set_state(struct cpuhp_cpu_state *st, enum cpuhp_state target) +cpuhp_set_state(int cpu, struct cpuhp_cpu_state *st, enum cpuhp_state target) { enum cpuhp_state prev_state = st->state; bool bringup = st->state < target; @@ -486,14 +486,15 @@ cpuhp_set_state(struct cpuhp_cpu_state *st, enum cpuhp_state target) st->target = target; st->single = false; st->bringup = bringup; - if (cpu_dying(st->cpu) != !bringup) - set_cpu_dying(st->cpu, !bringup); + if (cpu_dying(cpu) != !bringup) + set_cpu_dying(cpu, !bringup); return prev_state; } static inline void -cpuhp_reset_state(struct cpuhp_cpu_state *st, enum cpuhp_state prev_state) +cpuhp_reset_state(int cpu, struct cpuhp_cpu_state *st, + enum cpuhp_state prev_state) { bool bringup = !st->bringup; @@ -520,8 +521,8 @@ cpuhp_reset_state(struct cpuhp_cpu_state *st, enum cpuhp_state prev_state) } st->bringup = bringup; - if (cpu_dying(st->cpu) != !bringup) - set_cpu_dying(st->cpu, !bringup); + if (cpu_dying(cpu) != !bringup) + set_cpu_dying(cpu, !bringup); } /* Regular hotplug invocation of the AP hotplug thread */ @@ -541,15 +542,16 @@ static void __cpuhp_kick_ap(struct cpuhp_cpu_state *st) wait_for_ap_thread(st, st->bringup); } -static int cpuhp_kick_ap(struct cpuhp_cpu_state *st, enum cpuhp_state target) +static int cpuhp_kick_ap(int cpu, struct cpuhp_cpu_state *st, + enum cpuhp_state target) { enum cpuhp_state prev_state; int ret; - prev_state = cpuhp_set_state(st, target); + prev_state = cpuhp_set_state(cpu, st, target); __cpuhp_kick_ap(st); if ((ret = st->result)) { - cpuhp_reset_state(st, prev_state); + cpuhp_reset_state(cpu, st, prev_state); __cpuhp_kick_ap(st); } @@ -581,7 +583,7 @@ static int bringup_wait_for_ap(unsigned int cpu) if (st->target <= CPUHP_AP_ONLINE_IDLE) return 0; - return cpuhp_kick_ap(st, st->target); + return cpuhp_kick_ap(cpu, st, st->target); } static int bringup_cpu(unsigned int cpu) @@ -704,7 +706,7 @@ static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, ret, cpu, cpuhp_get_step(st->state)->name, st->state); - cpuhp_reset_state(st, prev_state); + cpuhp_reset_state(cpu, st, prev_state); if (can_rollback_cpu(st)) WARN_ON(cpuhp_invoke_callback_range(false, cpu, st, prev_state)); @@ -715,15 +717,6 @@ static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, /* * The cpu hotplug threads manage the bringup and teardown of the cpus */ -static void cpuhp_create(unsigned int cpu) -{ - struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); - - init_completion(&st->done_up); - init_completion(&st->done_down); - st->cpu = cpu; -} - static int cpuhp_should_run(unsigned int cpu) { struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); @@ -875,7 +868,7 @@ static int cpuhp_kick_ap_work(unsigned int cpu) cpuhp_lock_release(true); trace_cpuhp_enter(cpu, st->target, prev_state, cpuhp_kick_ap_work); - ret = cpuhp_kick_ap(st, st->target); + ret = cpuhp_kick_ap(cpu, st, st->target); trace_cpuhp_exit(cpu, st->state, prev_state, ret); return ret; @@ -883,15 +876,27 @@ static int cpuhp_kick_ap_work(unsigned int cpu) static struct smp_hotplug_thread cpuhp_threads = { .store = &cpuhp_state.thread, - .create = &cpuhp_create, .thread_should_run = cpuhp_should_run, .thread_fn = cpuhp_thread_fun, .thread_comm = "cpuhp/%u", .selfparking = true, }; +static __init void cpuhp_init_state(void) +{ + struct cpuhp_cpu_state *st; + int cpu; + + for_each_possible_cpu(cpu) { + st = per_cpu_ptr(&cpuhp_state, cpu); + init_completion(&st->done_up); + init_completion(&st->done_down); + } +} + void __init cpuhp_threads_init(void) { + cpuhp_init_state(); BUG_ON(smpboot_register_percpu_thread(&cpuhp_threads)); kthread_unpark(this_cpu_read(cpuhp_state.thread)); } @@ -1107,7 +1112,7 @@ static int cpuhp_down_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, ret, cpu, cpuhp_get_step(st->state)->name, st->state); - cpuhp_reset_state(st, prev_state); + cpuhp_reset_state(cpu, st, prev_state); if (st->state < prev_state) WARN_ON(cpuhp_invoke_callback_range(true, cpu, st, @@ -1134,7 +1139,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, cpuhp_tasks_frozen = tasks_frozen; - prev_state = cpuhp_set_state(st, target); + prev_state = cpuhp_set_state(cpu, st, target); /* * If the current CPU state is in the range of the AP hotplug thread, * then we need to kick the thread. @@ -1165,7 +1170,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, ret = cpuhp_down_callbacks(cpu, st, target); if (ret && st->state < prev_state) { if (st->state == CPUHP_TEARDOWN_CPU) { - cpuhp_reset_state(st, prev_state); + cpuhp_reset_state(cpu, st, prev_state); __cpuhp_kick_ap(st); } else { WARN(1, "DEAD callback error for CPU%d", cpu); @@ -1186,6 +1191,12 @@ out: static int cpu_down_maps_locked(unsigned int cpu, enum cpuhp_state target) { + /* + * If the platform does not support hotplug, report it explicitly to + * differentiate it from a transient offlining failure. + */ + if (cc_platform_has(CC_ATTR_HOTPLUG_DISABLED)) + return -EOPNOTSUPP; if (cpu_hotplug_disabled) return -EBUSY; return _cpu_down(cpu, 0, target); @@ -1352,7 +1363,7 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen, enum cpuhp_state target) cpuhp_tasks_frozen = tasks_frozen; - cpuhp_set_state(st, target); + cpuhp_set_state(cpu, st, target); /* * If the current CPU state is in the range of the AP hotplug thread, * then we need to kick the thread once more. |