Re: [PATCH 6/8] arm64: Introduce raw_{d,i}cache_line_size

From: Will Deacon
Date: Mon Aug 22 2016 - 06:00:46 EST


On Thu, Aug 18, 2016 at 02:10:30PM +0100, Suzuki K Poulose wrote:
> On systems with mismatched i/d cache min line sizes, we need to use
> the smallest size possible across all CPUs. This will be done by fetching
> the system wide safe value from CPU feature infrastructure.
> However the some special users(e.g kexec, hibernate) would need the line
> size on the CPU (rather than the system wide), when the system wide
> feature may not be accessible. Provide another helper which will fetch
> cache line size on the current CPU.

Why are these users "special"? Using a smaller line size shouldn't affect
correctness, and I don't see kexec and hibernate as being performance
critical in their cache maintenance.

Will