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-Software emulation of deprecated SWP instruction (CONFIG_SWP_EMULATE)
-ARMv6 architecture deprecates use of the SWP/SWPB instructions, and recommeds
-moving to the load-locked/store-conditional instructions LDREX and STREX.
-ARMv7 multiprocessing extensions introduce the ability to disable these
-instructions, triggering an undefined instruction exception when executed.
-Trapped instructions are emulated using an LDREX/STREX or LDREXB/STREXB
-sequence. If a memory access fault (an abort) occurs, a segmentation fault is
-signalled to the triggering process.
-/proc/cpu/swp_emulation holds some statistics/information, including the PID of
-the last process to trigger the emulation to be invocated. For example:
-Emulated SWP: 12
-Emulated SWPB: 0
-Aborted SWP{B}: 1
-Last process: 314
-NOTE: when accessing uncached shared regions, LDREX/STREX rely on an external
-transaction monitoring block called a global monitor to maintain update
-atomicity. If your system does not implement a global monitor, this option can
-cause programs that perform SWP operations to uncached memory to deadlock, as
-the STREX operation will always fail.