1 Commits

Author	SHA1	Message	Date
Ingo Molnar	669f6f96c6	Documentation/features: Explain kernel feature descriptions and add visualization script ... The previous patches added arch support matrices for more than 40 generic kernel features that need per architecture support. The structure of the feature descriptions is the following: Each feature has its own directory under Documentation/features/subsystem_name/feature_name/, and the arch-support.txt file shows its current arch porting status. For example, lockdep support is shown the following way: triton:~/tip> cat Documentation/features/locking/lockdep/arch-support.txt # # Feature name: lockdep # Kconfig: LOCKDEP_SUPPORT # description: arch supports the runtime locking correctness debug facility # ----------------------- | arch |status| ----------------------- | alpha: | TODO | | arc: | ok | | arm: | ok | | arm64: | ok | | avr32: | ok | | blackfin: | ok | | c6x: | TODO | | cris: | TODO | | frv: | TODO | | h8300: | TODO | | hexagon: | ok | | ia64: | TODO | | m32r: | TODO | | m68k: | TODO | | metag: | ok | | microblaze: | ok | | mips: | ok | | mn10300: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | | s390: | ok | | score: | ok | | sh: | ok | | sparc: | ok | | tile: | ok | | um: | ok | | unicore32: | ok | | x86: | ok | | xtensa: | ok | ----------------------- For generic kernel features that need architecture support, the arch-support.txt file in each feature directory shows the arch support matrix, for all upstream Linux architectures. The meaning of entries in the tables is: | ok | # feature supported by the architecture |TODO| # feature not yet supported by the architecture | .. | # feature cannot be supported by the hardware This directory structure can be used in the future to add other files - such as porting guides, testing description, etc. The Documentation/features/ hierarchy may also include generic kernel features that works on every architecture, in that case the arch-support.txt file will list every architecture as supported. To list an architecture's unsupported features, just do something like: triton:~/tip> git grep -lE 'x86.*TODO' Documentation/features/*/*/arch-support.txt Documentation/features/lib/strncasecmp/arch-support.txt Documentation/features/time/arch-tick-broadcast/arch-support.txt which will print the list of not yet supported features. The Documentation/features/list-arch.sh script will print the current support matrix of one architecture: triton:~/tip> Documentation/features/list-arch.sh # # Kernel feature support matrix of the 'x86' architecture: # core/ BPF-JIT : ok | HAVE_BPF_JIT # arch supports BPF JIT optimizations core/ generic-idle-thread : ok | GENERIC_SMP_IDLE_THREAD # arch makes use of the generic SMP idle thread facility core/ jump-labels : ok | HAVE_ARCH_JUMP_LABEL # arch supports live patched, high efficiency branches core/ tracehook : ok | HAVE_ARCH_TRACEHOOK # arch supports tracehook (ptrace) register handling APIs debug/ gcov-profile-all : ok | ARCH_HAS_GCOV_PROFILE_ALL # arch supports whole-kernel GCOV code coverage profiling debug/ KASAN : ok | HAVE_ARCH_KASAN # arch supports the KASAN runtime memory checker debug/ kgdb : ok | HAVE_ARCH_KGDB # arch supports the kGDB kernel debugger debug/ kprobes : ok | HAVE_KPROBES # arch supports live patched kernel probe debug/ kprobes-on-ftrace : ok | HAVE_KPROBES_ON_FTRACE # arch supports combined kprobes and ftrace live patching debug/ kretprobes : ok | HAVE_KRETPROBES # arch supports kernel function-return probes debug/ optprobes : ok | HAVE_OPTPROBES # arch supports live patched optprobes debug/ stackprotector : ok | HAVE_CC_STACKPROTECTOR # arch supports compiler driven stack overflow protection debug/ uprobes : ok | ARCH_SUPPORTS_UPROBES # arch supports live patched user probes debug/ user-ret-profiler : ok | HAVE_USER_RETURN_NOTIFIER # arch supports user-space return from system call profiler io/ dma-api-debug : ok | HAVE_DMA_API_DEBUG # arch supports DMA debug facilities io/ dma-contiguous : ok | HAVE_DMA_CONTIGUOUS # arch supports the DMA CMA (continuous memory allocator) io/ dma_map_attrs : ok | HAVE_DMA_ATTRS # arch provides dma_*map*_attrs() APIs io/ sg-chain : ok | ARCH_HAS_SG_CHAIN # arch supports chained scatter-gather lists lib/ strncasecmp : TODO | __HAVE_ARCH_STRNCASECMP # arch provides an optimized strncasecmp() function locking/ cmpxchg-local : ok | HAVE_CMPXCHG_LOCAL # arch supports the this_cpu_cmpxchg() API locking/ lockdep : ok | LOCKDEP_SUPPORT # arch supports the runtime locking correctness debug facility locking/ queued-rwlocks : ok | ARCH_USE_QUEUED_RWLOCKS # arch supports queued rwlocks locking/ queued-spinlocks : ok | ARCH_USE_QUEUED_SPINLOCKS # arch supports queued spinlocks locking/ rwsem-optimized : ok | Optimized asm/rwsem.h # arch provides optimized rwsem APIs perf/ kprobes-event : ok | HAVE_REGS_AND_STACK_ACCESS_API # arch supports kprobes with perf events perf/ perf-regs : ok | HAVE_PERF_REGS # arch supports perf events register access perf/ perf-stackdump : ok | HAVE_PERF_USER_STACK_DUMP # arch supports perf events stack dumps sched/ numa-balancing : ok | ARCH_SUPPORTS_NUMA_BALANCING # arch supports NUMA balancing seccomp/ seccomp-filter : ok | HAVE_ARCH_SECCOMP_FILTER # arch supports seccomp filters time/ arch-tick-broadcast : TODO | ARCH_HAS_TICK_BROADCAST # arch provides tick_broadcast() time/ clockevents : ok | GENERIC_CLOCKEVENTS # arch support generic clock events time/ context-tracking : ok | HAVE_CONTEXT_TRACKING # arch supports context tracking for NO_HZ_FULL time/ irq-time-acct : ok | HAVE_IRQ_TIME_ACCOUNTING # arch supports precise IRQ time accounting time/ modern-timekeeping : ok | !ARCH_USES_GETTIMEOFFSET # arch does not use arch_gettimeoffset() anymore time/ virt-cpuacct : ok | HAVE_VIRT_CPU_ACCOUNTING # arch supports precise virtual CPU time accounting vm/ ELF-ASLR : ok | ARCH_HAS_ELF_RANDOMIZE # arch randomizes the stack, heap and binary images of ELF binaries vm/ huge-vmap : ok | HAVE_ARCH_HUGE_VMAP # arch supports the ioremap_pud_enabled() and ioremap_pmd_enabled() VM APIs vm/ ioremap_prot : ok | HAVE_IOREMAP_PROT # arch has ioremap_prot() vm/ numa-memblock : ok | HAVE_MEMBLOCK_NODE_MAP # arch supports NUMA aware memblocks vm/ PG_uncached : ok | ARCH_USES_PG_UNCACHED # arch supports the PG_uncached page flag vm/ pmdp_splitting_flush : ok | __HAVE_ARCH_PMDP_SPLITTING_FLUSH # arch supports the pmdp_splitting_flush() VM API vm/ pte_special : ok | __HAVE_ARCH_PTE_SPECIAL # arch supports the pte_special()/pte_mkspecial() VM APIs vm/ THP : ok | HAVE_ARCH_TRANSPARENT_HUGEPAGE # arch supports transparent hugepages Cc: <linux-api@vger.kernel.org> Cc: <linux-arch@vger.kernel.org> Cc: <linux-kernel@vger.kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>	2015-06-03 12:59:38 +02:00