Memory barriers in userspace? (Linux, x86-64)

c++ c multithreading lock-free memory-barriers
anon picture anon · Jul 26, 2009 · Viewed 11.5k times · Source

It is easy to set memory barriers on the kernel side: the macros mb, wmb, rmb, etc. are always in place thanks to the Linux kernel headers.

How to accomplish this on the user side?

Answer

nik picture nik · Jul 26, 2009

You are looking for the full memory barrier atomic builtins of gcc.

Please note the detail on the reference i gave here says,

The [following] builtins are intended to be compatible with those described in the Intel Itanium Processor-specific Application Binary Interface, section 7.4. As such, they depart from the normal GCC practice of using the “__builtin_” prefix, and further that they are overloaded such that they work on multiple types.

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