parisc: fix ldcw inline assembler
There are two reasons to expose the memory *a in the asm: 1) To prevent the compiler from discarding a preceeding write to *a, and 2) to prevent it from caching *a in a register over the asm. The change has had a few days testing with a SMP build of 2.6.22.19 running on a rp3440. This patch is about the correctness of the __ldcw() macro itself. The use of the macro should be confined to small inline functions to try to limit the effect of clobbering memory on GCC's optimization of loads and stores. Signed-off-by: NDave Anglin <dave.anglin@nrc-cnrc.gc.ca> Signed-off-by: NHelge Deller <deller@gmx.de> Signed-off-by: NKyle McMartin <kyle@mcmartin.ca>
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