Re: [PATCH tip/core/rcu 12/26] x86: Use the new schedule_user API on userspace preemption

Josh Triplett
2012-08-31T23:53:58Z

On Thu, Aug 30, 2012 at 02:05:29PM -0700, Paul E. McKenney wrote:
> From: Frederic Weisbecker <fweisbec@gmail.com>
>
> This way we can exit the RCU extended quiescent state before
> we schedule a new task from irq/exception exit.
>
> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
> Cc: Alessio Igor Bogani <abogani@kernel.org>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Avi Kivity <avi@redhat.com>
> Cc: Chris Metcalf <cmetcalf@tilera.com>
> Cc: Christoph Lameter <cl@linux.com>
> Cc: Geoff Levand <geoff@infradead.org>
> Cc: Gilad Ben Yossef <gilad@benyossef.com>
> Cc: Hakan Akkan <hakanakkan@gmail.com>
> Cc: H. Peter Anvin <hpa@zytor.com>
> Cc: Ingo Molnar <mingo@kernel.org>
> Cc: Josh Triplett <josh@joshtriplett.org>
> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Max Krasnyansky <maxk@qualcomm.com>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Stephen Hemminger <shemminger@vyatta.com>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Cc: Sven-Thorsten Dietrich <thebigcorporation@gmail.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Reviewed-by: Josh Triplett <josh@joshtriplett.org>

> arch/x86/kernel/entry_64.S | 8 ++++----
> 1 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
> index 69babd8..6230487 100644
> --- a/arch/x86/kernel/entry_64.S
> +++ b/arch/x86/kernel/entry_64.S
> @@ -565,7 +565,7 @@ sysret_careful:
> TRACE_IRQS_ON
> ENABLE_INTERRUPTS(CLBR_NONE)
> pushq_cfi %rdi
> - call schedule
> + call schedule_user
> popq_cfi %rdi
> jmp sysret_check
>
> @@ -678,7 +678,7 @@ int_careful:
> TRACE_IRQS_ON
> ENABLE_INTERRUPTS(CLBR_NONE)
> pushq_cfi %rdi
> - call schedule
> + call schedule_user
> popq_cfi %rdi
> DISABLE_INTERRUPTS(CLBR_NONE)
> TRACE_IRQS_OFF
> @@ -974,7 +974,7 @@ retint_careful:
> TRACE_IRQS_ON
> ENABLE_INTERRUPTS(CLBR_NONE)
> pushq_cfi %rdi
> - call schedule
> + call schedule_user
> popq_cfi %rdi
> GET_THREAD_INFO(%rcx)
> DISABLE_INTERRUPTS(CLBR_NONE)
> @@ -1449,7 +1449,7 @@ paranoid_userspace:
> paranoid_schedule:
> TRACE_IRQS_ON
> ENABLE_INTERRUPTS(CLBR_ANY)
> - call schedule
> + call schedule_user
> DISABLE_INTERRUPTS(CLBR_ANY)
> TRACE_IRQS_OFF
> jmp paranoid_userspace
> --
> 1.7.8
>