linux-dev/arch/csky/kernel/Makefile, branch master

kbuild: use obj-y instead extra-y for objects placed at the head

2022-10-02T09:04:05Z

The objects placed at the head of vmlinux need special treatments: - arch/$(SRCARCH)/Makefile adds them to head-y in order to place them before other archives in the linker command line. - arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of obj-y to avoid them going into built-in.a. This commit gets rid of the latter. Create vmlinux.a to collect all the objects that are unconditionally linked to vmlinux. The objects listed in head-y are moved to the head of vmlinux.a by using 'ar m'. With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y for builtin objects. There is no *.o that is directly linked to vmlinux. Drop unneeded code in scripts/clang-tools/gen_compile_commands.py. $(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested by Nathan Chancellor [1]. [1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/ Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier

csky: Add jump-label implementation

2022-07-30T15:12:03Z

Add jump-label implementation for static branch Signed-off-by: Guo Ren Signed-off-by: Guo Ren

csky: optimize memcpy_{from,to}io() and memset_io()

2022-04-18T13:23:55Z

Optimize memcpy_{from,to}io() and memset_io() by transferring in 64 bit as much as possible with minimized barrier usage. This simplest optimization brings faster throughput compare to current byte-by-byte read and write with barrier in the loop. Code's skeleton is taken from the powerpc & arm64. Signed-off-by: Guo Ren Signed-off-by: Guo Ren

csky: Reconstruct VDSO framework

2021-01-12T01:52:41Z

Reconstruct vdso framework to support future vsyscall, vgettimeofday features. These are very important features to reduce system calls into the kernel for performance improvement. The patch is reference RISC-V's Signed-off-by: Guo Ren Cc: Palmer Dabbelt

csky: Fixup calltrace panic

2020-05-13T09:55:06Z

The implementation of show_stack will panic with wrong fp: addr = *fp++; because the fp isn't checked properly. The current implementations of show_stack, wchan and stack_trace haven't been designed properly, so just deprecate them. This patch is a reference to riscv's way, all codes are modified from arm's. The patch is passed with: - cat /proc//stack - cat /proc//wchan - echo c > /proc/sysrq-trigger Signed-off-by: Guo Ren

csky: Add kprobes supported

2020-04-03T03:14:17Z

This patch enable kprobes, kretprobes, ftrace interface. It utilized software breakpoint and single step debug exceptions, instructions simulation on csky. We use USR_BKPT replace origin instruction, and the kprobe handler prepares an excutable memory slot for out-of-line execution with a copy of the original instruction being probed. Most of instructions could be executed by single-step, but some instructions need origin pc value to execute and we need software simulate these instructions. Signed-off-by: Guo Ren Cc: Arnd Bergmann Cc: Steven Rostedt (VMware)

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46Z

Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

csky: Add support for perf registers sampling

2019-04-22T05:44:57Z

This patch implements the perf registers sampling and validation API for csky arch. The valid registers and their register ID are defined in perf_regs.h. Perf tool can backtrace in userspace with unwind library and the registers/user stack dump support. Signed-off-by: Mao Han Signed-off-by: Guo Ren

csky: Add perf callchain support

2019-04-22T05:44:57Z

This patch add support for perf callchain sampling on csky platform. As fp is used to unwind the stack, the program being sampled and the C library need to be compiled with -mbacktrace for user callchains, kernel callchains require CONFIG_STACKTRACE = y. Changelog: - Coding convention with Christoph's advice for riscv's. Signed-off-by: Mao Han Signed-off-by: Guo Ren Cc: Christoph Hellwig

csky: Add perf support for C-SKY

2019-01-02T14:17:11Z

This adds basic perf support for all C-SKY CPUs. Hardware events are only supported by 807/810/860. Signed-off-by: Guo Ren