>-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On Behalf Of Steven Rostedt >Sent: Thursday, January 10, 2008 6:44 AM >To: Ingo Molnar >Cc: LKML; Linus Torvalds; Andrew Morton; Thomas Gleixner; >Brown, Len; Pallipadi, Venkatesh; Adam Belay; Peter Zijlstra; >Andi Kleen >Subject: Re: [PATCH] Kick CPUS that might be sleeping in cpus_idle_wait > > > >On Thu, 10 Jan 2008, Ingo Molnar wrote: >> > FYI, I just hit this hang on 2.6.24-rc6 without any extra >patches. So, >> > unless 2.6.24-rc7 did anything to fix this issue, this is a high >> > priority bug (IMHO). >> >> i'm wondering why this only triggered now. Is this something new in >> 2.6.24? > >It only triggeres with the switching of the idle governors. >And not just >one, you need to switch twice. The first loading of a governor does not >call cpu_idle_wait, but the second one does. NO_HZ must also >be enabled, >plus this needs to happen when no events or threads are >scheduled to run >on a CPU, which limits this to boot up. > >Also, this only seems to happen on my 2x2 (4way) and only once >in a while. > >I'm surprised that I'm the only one so far to report it. I can >boot up the >2.6.23 kernel on this box to see if it also hangs sometimes. But, as I >said, it may take several hundreds of tries to see it.
With 2.6.23, you can try compiling acpi processor.ko as a module and doing insmod and rmmod in a loop. That should call cpu_idle_wait very frequently. Thanks, Venki -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
