| Message ID | 20110517233551.GA3511@schlenkerla.am.freescale.net (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Kumar Gala |
| Headers | show |
On May 17, 2011, at 6:35 PM, Scott Wood wrote: > From: yu liu <yu.liu@freescale.com> > > giveup_spe() saves the SPE state which is protected by MSR[SPE]. > However, modifying SPEFSCR does not trap when MSR[SPE]=0. > And since SPEFSCR is already saved/restored in _switch(), > not all the callers want to save SPEFSCR again. > Thus, saving SPEFSCR should not belong to giveup_spe(). > > This patch moves SPEFSCR saving to flush_spe_to_thread(), > and cleans up the caller that needs to save SPEFSCR accordingly. > > Signed-off-by: Liu Yu <yu.liu@freescale.com> > Signed-off-by: Scott Wood <scottwood@freescale.com> > --- > This is a resending of http://patchwork.ozlabs.org/patch/88677/ > > Kumar, please ack to go via kvm. This is holding up the rest of the SPE > patches, which in turn are holding up the MMU patches due to both > touching the MSR update code. > > arch/powerpc/kernel/head_fsl_booke.S | 2 -- > arch/powerpc/kernel/process.c | 1 + > arch/powerpc/kernel/traps.c | 5 +---- > 3 files changed, 2 insertions(+), 6 deletions(-) Acked-by: Kumar Gala <galak@kernel.crashing.org> [ Alex, let me know if you want this via my powerpc.git tree or your kvm tree ] - k
On 05/19/2011 08:04 AM, Kumar Gala wrote: > On May 17, 2011, at 6:35 PM, Scott Wood wrote: > >> From: yu liu<yu.liu@freescale.com> >> >> giveup_spe() saves the SPE state which is protected by MSR[SPE]. >> However, modifying SPEFSCR does not trap when MSR[SPE]=0. >> And since SPEFSCR is already saved/restored in _switch(), >> not all the callers want to save SPEFSCR again. >> Thus, saving SPEFSCR should not belong to giveup_spe(). >> >> This patch moves SPEFSCR saving to flush_spe_to_thread(), >> and cleans up the caller that needs to save SPEFSCR accordingly. >> >> Signed-off-by: Liu Yu<yu.liu@freescale.com> >> Signed-off-by: Scott Wood<scottwood@freescale.com> >> --- >> This is a resending of http://patchwork.ozlabs.org/patch/88677/ >> >> Kumar, please ack to go via kvm. This is holding up the rest of the SPE >> patches, which in turn are holding up the MMU patches due to both >> touching the MSR update code. >> >> arch/powerpc/kernel/head_fsl_booke.S | 2 -- >> arch/powerpc/kernel/process.c | 1 + >> arch/powerpc/kernel/traps.c | 5 +---- >> 3 files changed, 2 insertions(+), 6 deletions(-) > Acked-by: Kumar Gala<galak@kernel.crashing.org> > > [ Alex, let me know if you want this via my powerpc.git tree or your kvm tree ] I'll take them :). Thanks! Alex
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 5ecf54c..aede4f8 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -792,8 +792,6 @@ _GLOBAL(giveup_spe) evmwumiaa evr6, evr6, evr6 /* evr6 <- ACC = 0 * 0 + ACC */ li r4,THREAD_ACC evstddx evr6, r4, r3 /* save off accumulator */ - mfspr r6,SPRN_SPEFSCR - stw r6,THREAD_SPEFSCR(r3) /* save spefscr register value */ beq 1f lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5) lis r3,MSR_SPE@h diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index f74f355..138e7dd 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -213,6 +213,7 @@ void flush_spe_to_thread(struct task_struct *tsk) #ifdef CONFIG_SMP BUG_ON(tsk != current); #endif + tsk->thread.spefscr = mfspr(SPRN_SPEFSCR); giveup_spe(tsk); } preempt_enable(); diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 5ddb801..742a0fb 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1356,10 +1356,7 @@ void SPEFloatingPointException(struct pt_regs *regs) int code = 0; int err; - preempt_disable(); - if (regs->msr & MSR_SPE) - giveup_spe(current); - preempt_enable(); + flush_spe_to_thread(current); spefscr = current->thread.spefscr; fpexc_mode = current->thread.fpexc_mode;