powerpc/e500: Save SPEFCSR in flush_spe_to_thread()

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>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
yu liu 2011-06-14 18:34:25 -05:00 committed by Avi Kivity
parent a22a2daccf
commit 685659ee70
3 changed files with 2 additions and 6 deletions

View File

@ -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

View File

@ -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();

View File

@ -1387,10 +1387,7 @@ 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;