Messages in this thread | | | Date | Thu, 8 Jan 2009 11:49:05 +0900 | From | KAMEZAWA Hiroyuki <> | Subject | Re: [PATCH -v5][RFC]: mutex: implement adaptive spinning |
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On Wed, 7 Jan 2009 21:33:31 -0500 (EST) Steven Rostedt <rostedt@goodmis.org> wrote:
> > On Wed, 7 Jan 2009, Linus Torvalds wrote: > > > Should that be: > > > > > > #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_MEMORY_HOTPLUG) > > > > Well, probably CONFIG_MEMORY_HOTREMOVE, no? And I'd actually suggest that > > unplugging should have a stop-machine if it doesn't already, just because > > it's such a special case - like module removal. > > I do not think stop-machine will help, unless that spinning is protected > by preempt-disable. If the task gets preempted after grabbing the owner > thread_info, and then stop-machine runs, the memory disappears, the task > is scheduled back, accesses the owner thread_info and then page-fault. > How about recording "cpu" into mutex at locking explicitly ? too bad ?
-Kame
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