mirror of https://gitee.com/openkylin/linux.git
33940d0993
The target code has a rather generous helping of smp_mb__after_atomic() throughout the code base. Most atomic operations were followed by one and none were preceded by smp_mb__before_atomic(), nor accompanied by a comment explaining the need for a barrier. Instead of trying to prove for every case whether or not it is needed, this patch introduces atomic_inc_mb() and atomic_dec_mb(), which explicitly include the memory barriers before and after the atomic operation. For now they are defined in a target header, although they could be of general use. Most of the existing atomic/mb combinations were replaced by the new helpers. In a few cases the atomic was sandwiched in spin_lock/spin_unlock and I simply removed the barrier. I suspect that in most cases the correct conversion would have been to drop the barrier. I also suspect that a few cases exist where a) the barrier was necessary and b) a second barrier before the atomic would have been necessary and got added by this patch. Signed-off-by: Joern Engel <joern@logfs.org> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> |
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acpi | ||
asm-generic | ||
clocksource | ||
crypto | ||
drm | ||
dt-bindings | ||
keys | ||
kvm | ||
linux | ||
math-emu | ||
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