On Fri, 17 Nov 2006 23:33:45 -0500 (EST) Alan Stern <[EMAIL PROTECTED]> wrote:
> On Fri, 17 Nov 2006, Paul E. McKenney wrote: > > > > Perhaps a better approach to the initialization problem would be to > > > assume > > > that either: > > > > > > 1. The srcu_struct will be initialized before it is used, or > > > > > > 2. When it is used before initialization, the system is running > > > only one thread. > > > > Are these assumptions valid? If so, they would indeed simplify things > > a bit. > > I don't know. Maybe Andrew can tell us -- is it true that the kernel runs > only one thread up through the time the core_initcalls are finished? I don't see why - a core_initcall could go off and do the multithreaded-pci-probing thing, or it could call kernel_thread() or anything. I doubt if any core_initcall functions _do_ do that, but there are a lot of them. > If not, can we create another initcall level that is guaranteed to run > before any threads are spawned? It's a simple and cheap matter to create a precore_initcall() - one would need to document it carefully to be able to preserve whatever guarantees it needs. However by the time the initcalls get run, various thing are already happening: SMP is up, the keventd threads are running, the CPU scheduler migration threads are running, ksoftirqd, softlockup-detector, etc. keventd is the problematic one. So I guess you'd need a new linker section and a call from do_pre_smp_initcalls() or thereabouts. - 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/
