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author | Thomas Gleixner <tglx@linutronix.de> | 2016-02-26 19:43:37 +0100 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2016-03-01 20:36:56 +0100 |
commit | 2e1a3483ce74d197876e58281925dd4e378a7f28 (patch) | |
tree | 9a9ffcc23caad99b7e001336a0282911ca9c324d /kernel | |
parent | cpu/hotplug: Unpark smpboot threads from the state machine (diff) | |
download | linux-2e1a3483ce74d197876e58281925dd4e378a7f28.tar.xz linux-2e1a3483ce74d197876e58281925dd4e378a7f28.zip |
cpu/hotplug: Split out the state walk into functions
We need that for running callbacks on the AP and the BP.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.374946234@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/cpu.c | 111 |
1 files changed, 68 insertions, 43 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 3ec86bc414b7..9572ca043727 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -329,10 +329,74 @@ static int bringup_cpu(unsigned int cpu) return 0; } +/* + * Hotplug state machine related functions + */ +static void undo_cpu_down(unsigned int cpu, struct cpuhp_cpu_state *st, + struct cpuhp_step *steps) +{ + for (st->state++; st->state < st->target; st->state++) { + struct cpuhp_step *step = steps + st->state; + + if (!step->skip_onerr) + cpuhp_invoke_callback(cpu, st->state, step->startup); + } +} + +static int cpuhp_down_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, + struct cpuhp_step *steps, enum cpuhp_state target) +{ + enum cpuhp_state prev_state = st->state; + int ret = 0; + + for (; st->state > target; st->state--) { + struct cpuhp_step *step = steps + st->state; + + ret = cpuhp_invoke_callback(cpu, st->state, step->teardown); + if (ret) { + st->target = prev_state; + undo_cpu_down(cpu, st, steps); + break; + } + } + return ret; +} + +static void undo_cpu_up(unsigned int cpu, struct cpuhp_cpu_state *st, + struct cpuhp_step *steps) +{ + for (st->state--; st->state > st->target; st->state--) { + struct cpuhp_step *step = steps + st->state; + + if (!step->skip_onerr) + cpuhp_invoke_callback(cpu, st->state, step->teardown); + } +} + +static int cpuhp_up_callbacks(unsigned int cpu, struct cpuhp_cpu_state *st, + struct cpuhp_step *steps, enum cpuhp_state target) +{ + enum cpuhp_state prev_state = st->state; + int ret = 0; + + while (st->state < target) { + struct cpuhp_step *step; + + st->state++; + step = steps + st->state; + ret = cpuhp_invoke_callback(cpu, st->state, step->startup); + if (ret) { + st->target = prev_state; + undo_cpu_up(cpu, st, steps); + break; + } + } + return ret; +} + #ifdef CONFIG_HOTPLUG_CPU EXPORT_SYMBOL(register_cpu_notifier); EXPORT_SYMBOL(__register_cpu_notifier); - void unregister_cpu_notifier(struct notifier_block *nb) { cpu_maps_update_begin(); @@ -537,15 +601,6 @@ static int notify_dead(unsigned int cpu) #endif #ifdef CONFIG_HOTPLUG_CPU -static void undo_cpu_down(unsigned int cpu, struct cpuhp_cpu_state *st) -{ - for (st->state++; st->state < st->target; st->state++) { - struct cpuhp_step *step = cpuhp_bp_states + st->state; - - if (!step->skip_onerr) - cpuhp_invoke_callback(cpu, st->state, step->startup); - } -} /* Requires cpu_add_remove_lock to be held */ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, @@ -567,16 +622,8 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen, prev_state = st->state; st->target = target; - for (; st->state > st->target; st->state--) { - struct cpuhp_step *step = cpuhp_bp_states + st->state; + ret = cpuhp_down_callbacks(cpu, st, cpuhp_bp_states, target); - ret = cpuhp_invoke_callback(cpu, st->state, step->teardown); - if (ret) { - st->target = prev_state; - undo_cpu_down(cpu, st); - break; - } - } hasdied = prev_state != st->state && st->state == CPUHP_OFFLINE; cpu_hotplug_done(); @@ -645,22 +692,12 @@ static int cpuhp_set_cpu_active(unsigned int cpu) return 0; } -static void undo_cpu_up(unsigned int cpu, struct cpuhp_cpu_state *st) -{ - for (st->state--; st->state > st->target; st->state--) { - struct cpuhp_step *step = cpuhp_bp_states + st->state; - - if (!step->skip_onerr) - cpuhp_invoke_callback(cpu, st->state, step->teardown); - } -} - /* Requires cpu_add_remove_lock to be held */ 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; - int prev_state, ret = 0; + int ret = 0; cpu_hotplug_begin(); @@ -687,20 +724,8 @@ static int _cpu_up(unsigned int cpu, int tasks_frozen, enum cpuhp_state target) cpuhp_tasks_frozen = tasks_frozen; - prev_state = st->state; st->target = target; - while (st->state < st->target) { - struct cpuhp_step *step; - - st->state++; - step = cpuhp_bp_states + st->state; - ret = cpuhp_invoke_callback(cpu, st->state, step->startup); - if (ret) { - st->target = prev_state; - undo_cpu_up(cpu, st); - break; - } - } + ret = cpuhp_up_callbacks(cpu, st, cpuhp_bp_states, target); out: cpu_hotplug_done(); return ret; |