md: minor cleanup in safe_delay_store.

There isn't really much room for races with ->safemode_delay.
But as I am trying to clean up any racy code and will soon
be removing reconfig_mutex protection from most _store()
functions:
 - only set mddev->safemode_delay once, to ensure no code
   can see an intermediate value
 - use safemode_timer to call md_safemode_timeout() rather than
   calling it directly, to ensure it never races with itself.

Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
NeilBrown 2014-12-15 12:57:00 +11:00
parent 4af1a04176
commit 1b30e66f5a
1 changed files with 7 additions and 5 deletions

View File

@ -3242,11 +3242,13 @@ safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
mddev->safemode_delay = 0;
else {
unsigned long old_delay = mddev->safemode_delay;
mddev->safemode_delay = (msec*HZ)/1000;
if (mddev->safemode_delay == 0)
mddev->safemode_delay = 1;
if (mddev->safemode_delay < old_delay || old_delay == 0)
md_safemode_timeout((unsigned long)mddev);
unsigned long new_delay = (msec*HZ)/1000;
if (new_delay == 0)
new_delay = 1;
mddev->safemode_delay = new_delay;
if (new_delay < old_delay || old_delay == 0)
mod_timer(&mddev->safemode_timer, jiffies+1);
}
return len;
}