+config SWP_EMULATE
+ bool "Emulate SWP/SWPB instructions"
+ help
+ ARMv6 architecture deprecates use of the SWP/SWPB instructions. ARMv8
+ oblosetes the use of SWP/SWPB instructions. ARMv7 multiprocessing
+ extensions introduce the ability to disable these instructions,
+ triggering an undefined instruction exception when executed. Say Y
+ here to enable software emulation of these instructions for userspace
+ (not kernel) using LDREX/STREX. Also creates /proc/cpu/swp_emulation
+ for statistics.
+
+ In some older versions of glibc [<=2.8] SWP is used during futex
+ trylock() operations with the assumption that the code will not
+ be preempted. This invalid assumption may be more likely to fail
+ with SWP emulation enabled, leading to deadlock of the user
+ application.
+
+ 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.
+
+ If unsure, say Y.
+