tree 4a16400f9dc5667da0e16a4ac9cbf9764773f21d
parent e4c0fc5f72bca11432297168338aef46c12793a4
author Nicholas Piggin <npiggin@gmail.com> 1496936167 +1000
committer Michael Ellerman <mpe@ellerman.id.au> 1497508479 +1000

powerpc/64: Drop reservation-clearing ldarx in context switch

There is no need to explicitly break the reservation in _switch,
because we are guaranteed that the context switch path will include a
larx/stcx.

Comment the guarantee and remove the reservation clear from _switch.

This is worth 1-2% in context switch performance.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>