Messages in this thread | | | Date | Mon, 24 Jun 2013 12:51:40 -0400 | From | Dave Jones <> | Subject | Re: frequent softlockups with 3.10rc6. |
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On Mon, Jun 24, 2013 at 12:24:39PM -0400, Steven Rostedt wrote:
> > Ah, this is the first victim of my new 'check sanity of nodes during list walks' patch. > > It's doing the same prev->next next->prev checking as list_add and friends. > > I'm looking at getting it into shape for a 3.12 merge after some other preparatory patches > > go into 3.11 > > OK, and you may need to make an exception for the ring buffer. To do a > lockless swap out of the reader page for one of the pages in the buffer, > it uses the 2 LSB as flags. Notice the "next=ffff880243288001", that "1" > is a flag that states the next page is the "header" page (next to be > read). We use cmpxchg to update the pages to handle races between the > reader and writer.
I just had a plumber come visit to replace my toilet. I think even he would say "dude, gross" about that hack.
Dave
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