kernel LINUX KERNEL MEMORY BARRIERS
NOTE: 这是非常好的内容，在 preshing Memory Barriers Are Like Source Control Operations 的最后也推荐了这篇文章。
DISCLAIMER
CONTENTS
(*) Abstract memory access model.
- Device operations.
- Guarantees.
(*) What are memory barriers?
- Varieties of memory barrier.
- What may not be assumed about memory barriers?
- Data dependency barriers (historical).
- Control dependencies.
- SMP barrier pairing.
- Examples of memory barrier sequences.
- Read memory barriers vs load speculation.
- Multicopy atomicity.
(*) Explicit kernel barriers.
- Compiler barrier.
- CPU memory barriers.
(*) Implicit kernel memory barriers.
- Lock acquisition functions.
- Interrupt disabling functions.
- Sleep and wake-up functions.
- Miscellaneous functions.
(*) Inter-CPU acquiring barrier effects.
- Acquires vs memory accesses.
(*) Where are memory barriers needed?
- Interprocessor interaction.
- Atomic operations.
- Accessing devices.
- Interrupts.
(*) Kernel I/O barrier effects.
(*) Assumed minimum execution ordering model.
(*) The effects of the cpu cache.
- Cache coherency.
- Cache coherency vs DMA.
- Cache coherency vs MMIO.
(*) The things CPUs get up to.
- And then there's the Alpha.
- Virtual Machine Guests.
(*) Example uses.
- Circular buffers.