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net: mvneta: reduce smp_processor_id() calling in mvneta_tx_done_gbe
In the loop of mvneta_tx_done_gbe(), we call the smp_processor_id()
each time, move the call out of the loop to optimize the code a bit.
Before the patch, the loop looks like(under arm64):
ldr x1, [x29,#120]
...
ldr w24, [x1,#36]
...
bl 0 <_raw_spin_lock>
str w24, [x27,#132]
...
After the patch, the loop looks like(under arm64):
...
bl 0 <_raw_spin_lock>
str w23, [x28,#132]
...
where w23 is loaded so be ready before the loop.
>From another side, mvneta_tx_done_gbe() is called from mvneta_poll()
which is in non-preemptible context, so it's safe to call the
smp_processor_id() function once.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>