[RFC][PATCHv2 8/8] printk: enable printk offloading

From: Sergey Senozhatsky
Date: Wed Mar 29 2017 - 05:29:57 EST


Initialize the kernel printing thread and enable printk()
offloading.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx>
---
kernel/printk/printk.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 0d96839bb450..acfdc50580db 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2796,6 +2796,25 @@ static int printk_kthread_func(void *data)
return 0;
}

+/*
+ * Init printk kthread at late_initcall stage, after core/arch/device/etc.
+ * initialization.
+ */
+static int __init init_printk_kthread(void)
+{
+ struct task_struct *thread;
+
+ thread = kthread_run(printk_kthread_func, NULL, "printk");
+ if (IS_ERR(thread)) {
+ pr_err("printk: unable to create printing thread\n");
+ return PTR_ERR(thread);
+ }
+
+ printk_kthread = thread;
+ return 0;
+}
+late_initcall(init_printk_kthread);
+
void wake_up_klogd(void)
{
preempt_disable();
--
2.12.2