cpu/hotplug: Read_lock(tasklist_lock) doesn't need to disable irqs
check_for_tasks() doesn't need to disable irqs, recursive
read_lock() from interrupt is fine.
While at it, s/do_each_thread/for_each_process_thread/.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@odin.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Kirill Tkhai <ktkhai@parallels.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20150910130750.GA20055@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 82cf9df..050c634 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -304,8 +304,8 @@
{
struct task_struct *g, *p;
- read_lock_irq(&tasklist_lock);
- do_each_thread(g, p) {
+ read_lock(&tasklist_lock);
+ for_each_process_thread(g, p) {
if (!p->on_rq)
continue;
/*
@@ -320,8 +320,8 @@
pr_warn("Task %s (pid=%d) is on cpu %d (state=%ld, flags=%x)\n",
p->comm, task_pid_nr(p), dead_cpu, p->state, p->flags);
- } while_each_thread(g, p);
- read_unlock_irq(&tasklist_lock);
+ }
+ read_unlock(&tasklist_lock);
}
struct take_cpu_down_param {