Re: [PATCH 12/13] powerpc/64: runlatch CTRL[RUN] set optimisation

2017-06-15 Thread Michael Ellerman
Nicholas Piggin writes: > diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c > index baae104b16c7..f587c1fdf981 100644 > --- a/arch/powerpc/kernel/process.c > +++ b/arch/powerpc/kernel/process.c > @@ -1960,11 +1960,25 @@ void show_stack(struct task_struct *tsk, unsigned >

Re: [PATCH 12/13] powerpc/64: runlatch CTRL[RUN] set optimisation

2017-06-14 Thread Nicholas Piggin
On Wed, 14 Jun 2017 21:38:36 +1000 Michael Ellerman wrote: > Nicholas Piggin writes: > > > The CTRL register is read-only except bit 63 which is the run latch > > control. This means it can be updated with a mtspr rather than > > mfspr/mtspr. > > Turns out this doesn't work on Cell. > > The

Re: [PATCH 12/13] powerpc/64: runlatch CTRL[RUN] set optimisation

2017-06-14 Thread Michael Ellerman
Nicholas Piggin writes: > The CTRL register is read-only except bit 63 which is the run latch > control. This means it can be updated with a mtspr rather than > mfspr/mtspr. Turns out this doesn't work on Cell. There's an extra field in there: Thread enable bits (Read/Write) The hypervisor

[PATCH 12/13] powerpc/64: runlatch CTRL[RUN] set optimisation

2017-06-13 Thread Nicholas Piggin
The CTRL register is read-only except bit 63 which is the run latch control. This means it can be updated with a mtspr rather than mfspr/mtspr. Reviewed-by: Vaidyanathan Srinivasan Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/process.c | 12 ++-- 1 file changed, 2 insertions(+