Commit-ID: 2e1a3483ce74d197876e58281925dd4e378a7f28 Gitweb: http://git.kernel.org/tip/2e1a3483ce74d197876e58281925dd4e378a7f28 Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Fri, 26 Feb 2016 18:43:37 +0000 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Tue, 1 Mar 2016 20:36:56 +0100 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@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/20160226182341.374946234@xxxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- kernel/cpu.c | 111 ++++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 68 insertions(+), 43 deletions(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index 3ec86bc..9572ca0 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; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html