[PATCH] check_for_tasks: read_lock(tasklist_lock) doesn't need to disable irqs

From: Oleg Nesterov
Date: Thu Sep 10 2015 - 09:10:45 EST


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@xxxxxxxxxx>
---
kernel/cpu.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 94bbe46..24551f2 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -302,8 +302,8 @@ static inline void check_for_tasks(int dead_cpu)
{
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;
/*
@@ -318,8 +318,8 @@ static inline void check_for_tasks(int dead_cpu)

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 {
--
1.5.5.1


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/