On 10/02/16 02:46, Ralf Baechle wrote: > On Tue, Feb 09, 2016 at 12:55:54PM -0800, Florian Fainelli wrote: > >> Debugging a missing features in cpu-features-override.h, or a runtime feature >> set/clear in the vendor specific cpu_probe() function can be a little tedious, >> ease that by providing a debugfs entry representing the >> current_cpu_data.options bitmask. > > Hm.. Bits in the options bitmaps are not an ABI, they come and sometimes > they go as well and manual decoding can be tedious to humans. so I'm > wondering if something in /sys/devices/system/cpu would be more suitable. Not sure, you need this while bringing up systems and/or debugging why a kernel does not have this or that enabled as you think it should, outside of that, not so much probably?. More standard interfaces like /proc/cpuinfo should be used, but that does not give you the full picture. > It'd depend on just sysfs, not debugfs which is disabled in production > kernels. > > Thoughts? I suppose this is fine, in that case, we would probably want to go with a text-based approach to make the interface more stable. NB: I also have a patch that adds cache info reporting to MIPS, since it seems useful for people dealing with user-space cache flushes (graphics, JIT, etc.), Russell King rejected adding that for ARM, but ARM64 and x86 have it (arch/arm64/kernel/cacheinfo.c) would you oppose to having that for MIPS? -- Florian
