[patch 20/37] cpu/hotplug: Remove cpu_report_state() and related unused cruft

Thomas Gleixner
2023-04-14T23:46:45Z

No more users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/cpu.h | 2 -
kernel/smpboot.c | 90 ----------------------------------------------------
2 files changed, 92 deletions(-)

--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -184,8 +184,6 @@ void arch_cpu_idle_enter(void);
void arch_cpu_idle_exit(void);
void arch_cpu_idle_dead(void);

-int cpu_report_state(int cpu);
-int cpu_check_up_prepare(int cpu);
void cpu_set_state_online(int cpu);
void play_idle_precise(u64 duration_ns, u64 latency_ns);

--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -329,97 +329,7 @@ EXPORT_SYMBOL_GPL(smpboot_unregister_per
#ifndef CONFIG_HOTPLUG_CORE_SYNC
static DEFINE_PER_CPU(atomic_t, cpu_hotplug_state) = ATOMIC_INIT(CPU_POST_DEAD);

-/*
- * Called to poll specified CPU's state, for example, when waiting for
- * a CPU to come online.
- */
-int cpu_report_state(int cpu)
-{
- return atomic_read(&per_cpu(cpu_hotplug_state, cpu));
-}
-
-/*
- * If CPU has died properly, set its state to CPU_UP_PREPARE and
- * return success. Otherwise, return -EBUSY if the CPU died after
- * cpu_wait_death() timed out. And yet otherwise again, return -EAGAIN
- * if cpu_wait_death() timed out and the CPU still hasn't gotten around
- * to dying. In the latter two cases, the CPU might not be set up
- * properly, but it is up to the arch-specific code to decide.
- * Finally, -EIO indicates an unanticipated problem.
- *
- * Note that it is permissible to omit this call entirely, as is
- * done in architectures that do no CPU-hotplug error checking.
- */
-int cpu_check_up_prepare(int cpu)
-{
- if (!IS_ENABLED(CONFIG_HOTPLUG_CPU)) {
- atomic_set(&per_cpu(cpu_hotplug_state, cpu), CPU_UP_PREPARE);
- return 0;
- }
-
- switch (atomic_read(&per_cpu(cpu_hotplug_state, cpu))) {
-
- case CPU_POST_DEAD:
-
- /* The CPU died properly, so just start it up again. */
- atomic_set(&per_cpu(cpu_hotplug_state, cpu), CPU_UP_PREPARE);
- return 0;
-
- case CPU_DEAD_FROZEN:
-
- /*
- * Timeout during CPU death, so let caller know.
- * The outgoing CPU completed its processing, but after
- * cpu_wait_death() timed out and reported the error. The
- * caller is free to proceed, in which case the state
- * will be reset properly by cpu_set_state_online().
- * Proceeding despite this -EBUSY return makes sense
- * for systems where the outgoing CPUs take themselves
- * offline, with no post-death manipulation required from
- * a surviving CPU.
- */
- return -EBUSY;
-
- case CPU_BROKEN:
-
- /*
- * The most likely reason we got here is that there was
- * a timeout during CPU death, and the outgoing CPU never
- * did complete its processing. This could happen on
- * a virtualized system if the outgoing VCPU gets preempted
- * for more than five seconds, and the user attempts to
- * immediately online that same CPU. Trying again later
- * might return -EBUSY above, hence -EAGAIN.
- */
- return -EAGAIN;
-
- case CPU_UP_PREPARE:
- /*
- * Timeout while waiting for the CPU to show up. Allow to try
- * again later.
- */
- return 0;
-
- default:
-
- /* Should not happen. Famous last words. */
- return -EIO;
- }
-}
-
-/*
- * Mark the specified CPU online.
- *
- * Note that it is permissible to omit this call entirely, as is
- * done in architectures that do no CPU-hotplug error checking.
- */
-void cpu_set_state_online(int cpu)
-{
- (void)atomic_xchg(&per_cpu(cpu_hotplug_state, cpu), CPU_ONLINE);
-}
-
#ifdef CONFIG_HOTPLUG_CPU
-
/*
* Wait for the specified CPU to exit the idle loop and die.
*/