[PATCH 2/3] powerpc: POWER7 optimised memcpy using VMX
Benjamin Herrenschmidt
benh at kernel.crashing.org
Fri Jun 17 15:57:16 EST 2011
O
> +.Lvmx_copy:
> + mflr r0
> + std r4,56(r1)
> + std r5,64(r1)
> + std r0,16(r1)
> + stdu r1,-STACKFRAMESIZE(r1)
> + bl .enable_kernel_altivec
> + ld r0,STACKFRAMESIZE+16(r1)
> + ld r3,STACKFRAMESIZE+48(r1)
> + ld r4,STACKFRAMESIZE+56(r1)
> + ld r5,STACKFRAMESIZE+64(r1)
> + mtlr r0
Disable interrupts ? We wont save the VMX state on interrupts and memcpy
is definitely re-entrant.
Or only run the optimization when not at interrupt time....
Cheers,
Ben.
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