Re: [RFC] New locking primitive for 2.5

Andrew Morton
2002-02-07T20:01:04Z

Ingo Molnar wrote:
>
> On Thu, 7 Feb 2002, Andrew Morton wrote:
>
> > Quite a few. Significant ones. pagemap_lru_lock and lru_list_lock
> > come to mind.
>
> ugh. Are you sure we want to *sleep* with something like pagemap_lru_lock
> held?

Not guilty :) I was answering rml's question.

I suspect lru_list_lock is the shining example. We often
take it for very short periods and occasionally take it
for enormous periods.

> That pretty much brings all pagecache related operations to a
> grinding halt.

yup. We'd go into a sheduling storm until we find the process
which holds the lock.

> I think complex spinlocked sections should be simplified
> rather.

yes.

-