From 5fc57df2f6fdc18b9f9273f98318ff7919968c2c Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Mon, 14 Sep 2020 16:34:09 +0100 Subject: [PATCH] arm64: stacktrace: Convert to ARCH_STACKWALK Historically architectures have had duplicated code in their stack trace implementations for filtering what gets traced. In order to avoid this duplication some generic code has been provided using a new interface arch_stack_walk(), enabled by selecting ARCH_STACKWALK in Kconfig, which factors all this out into the generic stack trace code. Convert arm64 to use this common infrastructure. Signed-off-by: Mark Brown Reviewed-by: Miroslav Benes Link: https://lore.kernel.org/r/20200914153409.25097-4-broonie@kernel.org Signed-off-by: Will Deacon --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/stacktrace.c | 79 +++++----------------------------- 2 files changed, 11 insertions(+), 69 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6d232837cbee..d1ba52e4b976 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -29,6 +29,7 @@ config ARM64 select ARCH_HAS_SETUP_DMA_OPS select ARCH_HAS_SET_DIRECT_MAP select ARCH_HAS_SET_MEMORY + select ARCH_STACKWALK select ARCH_HAS_STRICT_KERNEL_RWX select ARCH_HAS_STRICT_MODULE_RWX select ARCH_HAS_SYNC_DMA_FOR_DEVICE diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index 05eaba21fd46..804d076b02cb 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -133,82 +133,23 @@ void notrace walk_stackframe(struct task_struct *tsk, struct stackframe *frame, NOKPROBE_SYMBOL(walk_stackframe); #ifdef CONFIG_STACKTRACE -struct stack_trace_data { - struct stack_trace *trace; - unsigned int no_sched_functions; - unsigned int skip; -}; -static bool save_trace(void *d, unsigned long addr) +void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie, + struct task_struct *task, struct pt_regs *regs) { - struct stack_trace_data *data = d; - struct stack_trace *trace = data->trace; - - if (data->no_sched_functions && in_sched_functions(addr)) - return false; - if (data->skip) { - data->skip--; - return false; - } - - trace->entries[trace->nr_entries++] = addr; - - return trace->nr_entries >= trace->max_entries; -} - -void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) -{ - struct stack_trace_data data; struct stackframe frame; - data.trace = trace; - data.skip = trace->skip; - data.no_sched_functions = 0; - - start_backtrace(&frame, regs->regs[29], regs->pc); - walk_stackframe(current, &frame, save_trace, &data); -} -EXPORT_SYMBOL_GPL(save_stack_trace_regs); - -static noinline void __save_stack_trace(struct task_struct *tsk, - struct stack_trace *trace, unsigned int nosched) -{ - struct stack_trace_data data; - struct stackframe frame; - - if (!try_get_task_stack(tsk)) - return; - - data.trace = trace; - data.skip = trace->skip; - data.no_sched_functions = nosched; - - if (tsk != current) { - start_backtrace(&frame, thread_saved_fp(tsk), - thread_saved_pc(tsk)); - } else { - /* We don't want this function nor the caller */ - data.skip += 2; + if (regs) + start_backtrace(&frame, regs->regs[29], regs->pc); + else if (task == current) start_backtrace(&frame, (unsigned long)__builtin_frame_address(0), - (unsigned long)__save_stack_trace); - } + (unsigned long)arch_stack_walk); + else + start_backtrace(&frame, thread_saved_fp(task), + thread_saved_pc(task)); - walk_stackframe(tsk, &frame, save_trace, &data); - - put_task_stack(tsk); + walk_stackframe(task, &frame, consume_entry, cookie); } -void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) -{ - __save_stack_trace(tsk, trace, 1); -} -EXPORT_SYMBOL_GPL(save_stack_trace_tsk); - -void save_stack_trace(struct stack_trace *trace) -{ - __save_stack_trace(current, trace, 0); -} - -EXPORT_SYMBOL_GPL(save_stack_trace); #endif