No. The spinlocks themselves contain the required SMP memory
synchronization points internally: otherwise they wouldn't be very
useful as locking primitives. For example, on intel any locked memory
reference (and the spinlocks do them) will act as a memory barrier, and
that's why you don't see any extra code in asm-i386/spinlocks.h - on
other architectures the spinlocks do other things to get the same goal.
See for example the asm-alpha/spinlocks.h file, which has the proper
explicit mb() calls (on the alpha, and any other sane SMP architecture,
the memory barrier issue is separate from any issue of atomicity).
Linus
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