On Tue, 22 Sep 2020, David Brazdil wrote: > Introduce '.hyp.data..percpu' as part of ongoing effort to make nVHE > hyp code self-contained and independent of the rest of the kernel. The percpu subsystems point is to enable the use of special hardware instructions that can perform address calculation and a memory operation in one interruptible instruction. This is in particular useful to avoid higher overhead for memory management related counters because preempt disable/enable etc can be avoided. ARM cannot do that and thus has a LC/SC loop. This is a patchset for ARM64 so its not clear to me what kind of advantage there would be against a simple implementation that does a regular fetch from a base address with an offset. > Main benefits: > * independent nVHE per-CPU data section that can be unmapped from host, > * more robust linking of nVHE hyp code, > * no need for hyp-specific macros to access per-CPU variables. Maybe simply don't use percpu variables for your arm code? Those pointers to data will be much more indepedent of the rest of the kernel and allow a much higher degree of being self-contained. _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
