[lkml]   [2005]   [Dec]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 1/19] MUTEX: Introduce simple mutex implementation
On Sat, 2005-12-17 at 16:43 -0700, Matthew Wilcox wrote:
> On Fri, Dec 16, 2005 at 11:34:03PM -0800, Linus Torvalds wrote:
> > I really can't think of any blocking kernel lock where priority
> > inheritance would make _any_ sense at all. Please give me an example.
> I have a better example of something we currently get wrong that I
> haven't heard any RT person worry about yet. If two tasks are sleeping
> on the same semaphore, the one to be woken up will be the first one to
> wait for it, not the highest-priority task.
> Obviously, this was introduced by the wake-one semantics. But how to
> fix it? Should we scan the entire queue looking for the best task to
> wake? Should we try to maintain the wait list in priority order? Or
> should we just not care? Should we document that we don't care? ;-)

It's well known that this is a problem:


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-12-18 01:04    [W:0.182 / U:6.528 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site