This is the third patch series for fixing stack tracer on arm64. The original issue was reported by Jungseok[1], and then I found more issues[2]. (Steven, Jungseok, sorry for not replying to your comments directly.)
I address here all the issues and implement fixes described in [2] except for interrupt-triggered problems, ie. II-3). Recent discussions[3] about introducing a dedicated interrupt stack suggests that we may avoid walking through from an interrupt stack to a process stack. (So interrupt-stack patch is a prerequisite.) Basically, patch1 corresponds to the original issue. patch2 is a proactive improvement of function_graph tracer. patch3 corresponds to II-4(functions under function_graph tracer). patch4 corresponds to II-5(leaf function). patch5, 6 and 7 correspond to II-1(slurping stack) and II-2(differences between x86 and arm64). Each fix can be applied independently, but if patch5, 6 and 7 are acceptable, patch1 is not necessary because patch7 replaces a default stack tracer. I tested the code with v4.3-rc3 + Jungseok's patch v3[4]. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/354126.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/355920.html [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-September/368003.html [4] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-September/371451.html AKASHI Takahiro (7): arm64: ftrace: adjust callsite addresses examined by stack tracer arm64: ftrace: modify a stack frame in a safe way arm64: ftrace: fix a stack tracer's output under function graph tracer arm64: ftrace: allow for tracing leaf functions ftrace: allow arch-specific stack tracer arm64: insn: add instruction decoders for ldp/stp and add/sub arm64: ftrace: add arch-specific stack tracer arch/arm64/Makefile | 5 + arch/arm64/include/asm/ftrace.h | 7 +- arch/arm64/include/asm/insn.h | 18 +++ arch/arm64/include/asm/stacktrace.h | 1 + arch/arm64/kernel/ftrace.c | 77 +++++++++++-- arch/arm64/kernel/insn.c | 102 +++++++++++++++++ arch/arm64/kernel/stacktrace.c | 213 ++++++++++++++++++++++++++++++++++- include/linux/ftrace.h | 17 +++ kernel/trace/trace_stack.c | 27 +++-- 9 files changed, 442 insertions(+), 25 deletions(-) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/