[tip:smp/hotplug] cpu/hotplug: Hand in target state to _cpu_up/down

From: tip-bot for Thomas Gleixner
Date: Tue Mar 01 2016 - 14:55:07 EST


Commit-ID: af1f40457da6f79b6a1d7e1198b32f671572abd2
Gitweb: http://git.kernel.org/tip/af1f40457da6f79b6a1d7e1198b32f671572abd2
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Fri, 26 Feb 2016 18:43:30 +0000
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Tue, 1 Mar 2016 20:36:54 +0100

cpu/hotplug: Hand in target state to _cpu_up/down

We want to be able to bringup/teardown the cpu to a particular state. Add a
target argument to _cpu_up/down.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-arch@xxxxxxxxxxxxxxx
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Rafael Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: "Srivatsa S. Bhat" <srivatsa@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Sebastian Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Paul McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Paul Turner <pjt@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20160226182340.862113133@xxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
kernel/cpu.c | 31 ++++++++++++++++++++-----------
1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 797723e..a00f8f6 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -547,7 +547,8 @@ static void undo_cpu_down(unsigned int cpu, struct cpuhp_cpu_state *st)
}

/* Requires cpu_add_remove_lock to be held */
-static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
+static int __ref _cpu_down(unsigned int cpu, int tasks_frozen,
+ enum cpuhp_state target)
{
struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
int prev_state, ret = 0;
@@ -564,7 +565,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
cpuhp_tasks_frozen = tasks_frozen;

prev_state = st->state;
- st->target = CPUHP_OFFLINE;
+ st->target = target;
for (; st->state > st->target; st->state--) {
struct cpuhp_step *step = cpuhp_bp_states + st->state;

@@ -584,7 +585,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
return ret;
}

-int cpu_down(unsigned int cpu)
+static int do_cpu_down(unsigned int cpu, enum cpuhp_state target)
{
int err;

@@ -595,12 +596,16 @@ int cpu_down(unsigned int cpu)
goto out;
}

- err = _cpu_down(cpu, 0);
+ err = _cpu_down(cpu, 0, target);

out:
cpu_maps_update_done();
return err;
}
+int cpu_down(unsigned int cpu)
+{
+ return do_cpu_down(cpu, CPUHP_OFFLINE);
+}
EXPORT_SYMBOL(cpu_down);
#endif /*CONFIG_HOTPLUG_CPU*/

@@ -669,7 +674,7 @@ static void undo_cpu_up(unsigned int cpu, struct cpuhp_cpu_state *st)
}

/* Requires cpu_add_remove_lock to be held */
-static int _cpu_up(unsigned int cpu, int tasks_frozen)
+static int _cpu_up(unsigned int cpu, int tasks_frozen, enum cpuhp_state target)
{
struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
struct task_struct *idle;
@@ -692,7 +697,7 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen)
cpuhp_tasks_frozen = tasks_frozen;

prev_state = st->state;
- st->target = CPUHP_ONLINE;
+ st->target = target;
while (st->state < st->target) {
struct cpuhp_step *step;

@@ -710,7 +715,7 @@ out:
return ret;
}

-int cpu_up(unsigned int cpu)
+static int do_cpu_up(unsigned int cpu, enum cpuhp_state target)
{
int err = 0;

@@ -734,12 +739,16 @@ int cpu_up(unsigned int cpu)
goto out;
}

- err = _cpu_up(cpu, 0);
-
+ err = _cpu_up(cpu, 0, target);
out:
cpu_maps_update_done();
return err;
}
+
+int cpu_up(unsigned int cpu)
+{
+ return do_cpu_up(cpu, CPUHP_ONLINE);
+}
EXPORT_SYMBOL_GPL(cpu_up);

#ifdef CONFIG_PM_SLEEP_SMP
@@ -762,7 +771,7 @@ int disable_nonboot_cpus(void)
if (cpu == first_cpu)
continue;
trace_suspend_resume(TPS("CPU_OFF"), cpu, true);
- error = _cpu_down(cpu, 1);
+ error = _cpu_down(cpu, 1, CPUHP_OFFLINE);
trace_suspend_resume(TPS("CPU_OFF"), cpu, false);
if (!error)
cpumask_set_cpu(cpu, frozen_cpus);
@@ -812,7 +821,7 @@ void enable_nonboot_cpus(void)

for_each_cpu(cpu, frozen_cpus) {
trace_suspend_resume(TPS("CPU_ON"), cpu, true);
- error = _cpu_up(cpu, 1);
+ error = _cpu_up(cpu, 1, CPUHP_ONLINE);
trace_suspend_resume(TPS("CPU_ON"), cpu, false);
if (!error) {
pr_info("CPU%d is up\n", cpu);