This article introduces ARM memory barrier instructions, DMB, DSB, ISB.
1.DMB(Data memory barrier):
Data storage isolation. The DMB instruction guarantees that a memory access operation following it is committed only after all memory access operations preceding it have been executed.
2.DSB(Data Synchronization Barrier):
Data synchronization isolation. Stricter than DMB: Executes the instruction following it only after all memory accesses preceding it have completed
3.ISB(Instruction Synchronization Barrier):
Instruction synchronization isolation. The strictest: It will clean the pipeline to ensure that all the instructions before it are executed before executing the instructions behind it.