On Fri, Jul 06, 2012 at 09:33:38AM -0700, Paul E. McKenney wrote: > On Fri, Jul 06, 2012 at 02:00:18PM +0200, Frederic Weisbecker wrote: > > do_notify_resume() may be called on irq exit but it won't > > be protected between rcu_irq_enter() and rcu_irq_exit() > > and we don't call rcu_user_exit() on irq entry (unlike > > syscalls/exceptions entry). > > > > Since it can use RCU read side critical section, we must call > > rcu_user_exit() before doing anything there. > > > > This complete support for RCU userspace extended quiescent state > > in x86. > > > > Signed-off-by: Frederic Weisbecker <[email protected]> > > Cc: Alessio Igor Bogani <[email protected]> > > Cc: Andrew Morton <[email protected]> > > Cc: Avi Kivity <[email protected]> > > Cc: Chris Metcalf <[email protected]> > > Cc: Christoph Lameter <[email protected]> > > Cc: Geoff Levand <[email protected]> > > Cc: Gilad Ben Yossef <[email protected]> > > Cc: Hakan Akkan <[email protected]> > > Cc: H. Peter Anvin <[email protected]> > > Cc: Ingo Molnar <[email protected]> > > Cc: Josh Triplett <[email protected]> > > Cc: Kevin Hilman <[email protected]> > > Cc: Max Krasnyansky <[email protected]> > > Cc: Peter Zijlstra <[email protected]> > > Cc: Stephen Hemminger <[email protected]> > > Cc: Steven Rostedt <[email protected]> > > Cc: Sven-Thorsten Dietrich <[email protected]> > > Cc: Thomas Gleixner <[email protected]> > > --- > > arch/x86/Kconfig | 1 + > > arch/x86/kernel/signal.c | 2 ++ > > 2 files changed, 3 insertions(+), 0 deletions(-) > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index c70684f..38dfcc2 100644 > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -95,6 +95,7 @@ config X86 > > select KTIME_SCALAR if X86_32 > > select GENERIC_STRNCPY_FROM_USER > > select GENERIC_STRNLEN_USER > > + select HAVE_RCU_USER_QS if X86_64 > > And I will bite yet again. Why only 64-bit kernels? > > Thanx, Paul
Because I don't want to spend time on implementing it the same way on 32 in case people disagree with the whole design :) -- 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/
