[question] Can the execution of the atomtic operation instruction pair lwarx/stwcx be interrrupted by local HW interruptions?

[Gavin Hu]

Hi

I notice that there is a pair ppc instructions lwarx and stwcx used to
atomtic operation for instance, atomic_inc/atomic_dec.

In some ppc manuals, they more emphasize its mechanism is that lwarx can
reseve the target memory address preventing other CORE from modifying it.

I assume that there is atomtic operation executing on the CORE0 in a
multicore system. In this situation, does the CORE0 disable the local HW
interrupt?
Can the executing process from the beginning of lwarx and end of stwcx be
interrupted by HW interruptions/exceptions?  Anyway, they are two assembly
instructions.

 Thanks a lot!

"1:    lwarx    %0,0,%2        # atomic_inc\n\
    addic    %0,%0,1\n"
"    stwcx.    %0,0,%2 \n\


BR
Gavin. Hu
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