c - Does inserting memory sync barrier after writing and before reading sharing variable also ensure the cache coherency -


if variable(not volatile) read/write accessed 2 threads without using locking , avoid locking , volatile using memory sync barriers before reading , after writing variable.

i read memory sync barrier serializes read/write operations mean write/read reflected in parallel other threads. cause processor cache invalidated thread can latest value instead of value in cache ?

the reason not using locks/volatile variable trying learn use memory sync barrier. may can me remove overhead of locks.


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