Re: Strange Badness with RT Spin Lock
flat view
From: Darcy Watkins <hidden>
Date: 2008-08-13 19:55:24
I have an update... First please disregard the follow-up email I sent mentioning memory barriers. That blew up shortly after I sent out the email. The problem appears to be resolved when I declare the spinlock variable using the __cacheline_aligned attribute (that is without the _in_smp suffix). Does anyone know of an explanation as to why a spinlock may need to be cacheline aligned in a uniprocessor system? Regards, Darcy On Fri, 2008-08-08 at 12:56 -0700, Darcy Watkins wrote:
Hello, I have a very unusual bug I have been trying to get to the bottom of. First the background... AMCC PPC405EP on embedded network device (simpler than a Taihu) Kernel 2.6.25.8-rt7 with incremental patches up to 2.6.25.13 mPCI slot with a WiMax radio card This is an RT-Preemption kernel. In my system, in a real time radio (WiMax) driver, I have code that makes use of a spinlock to control access to a tree structure... spinlock_t tree_lock;
-- Regards, Darcy -------------- Darcy L. Watkins - Senior Software Developer Tranzeo Wireless Technologies, Inc. 19273 Fraser Way, Pitt Meadows, BC, Canada V3Y 2V4 T:604-460-6002 ext:410 http://www.tranzeo.com