A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-29 11:11:45 -04:00
Code Issues Projects Releases Packages Wiki Activity

md: avoid potential long delay under pers_lock

Browse source 
printk may cause long time lapse if value of printk_delay in sysctl is
configured large by user. If register_md_personality takes long time to print in
spinlock pers_lock, we may encounter high CPU usage rate when there are other
pers_lock competitors who may be blocked to spin.
We can avoid this condition by moving printk out of coverage of pers_lock
spinlock.

Signed-off-by: Chao Yu <[email protected]>
Signed-off-by: NeilBrown <[email protected]>
This commit is contained in:
Chao Yu 2014-09-25 15:28:34 +08:00 • committed by NeilBrown
commit 50bd377405
1 changed files with 2 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

3
drivers/md/md.c
View file

@ -7187,9 +7187,10 @@ static const struct file_operations md_seq_fops = {
int register_md_personality(struct md_personality *p)
{
printk(KERN_INFO "md: %s personality registered for level %d\n",
p->name, p->level);
spin_lock(&pers_lock);
list_add_tail(&p->list, &pers_list);
printk(KERN_INFO "md: %s personality registered for level %d\n", p->name, p->level);
spin_unlock(&pers_lock);
return 0;
}