[PATCH 4/7] arch: Make ARCH_STACKWALK independent of STACKTRACE

From: Peter Zijlstra
Date: Fri Oct 22 2021 - 11:24:33 EST


Make arch_stack_walk() available for ARCH_STACKWALK architectures
without it being entangled in STACKTRACE.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/arm/kernel/stacktrace.c | 2 --
arch/arm64/kernel/stacktrace.c | 4 ----
arch/powerpc/kernel/Makefile | 3 +--
arch/riscv/kernel/stacktrace.c | 4 ----
arch/s390/kernel/Makefile | 3 +--
arch/x86/kernel/Makefile | 2 +-
include/linux/stacktrace.h | 33 +++++++++++++++++----------------
7 files changed, 20 insertions(+), 31 deletions(-)

--- a/arch/arm/kernel/stacktrace.c
+++ b/arch/arm/kernel/stacktrace.c
@@ -87,7 +87,6 @@ void notrace walk_stackframe(struct stac
}
EXPORT_SYMBOL(walk_stackframe);

-#ifdef CONFIG_STACKTRACE
noinline notrace void arch_stack_walk(stack_trace_consume_fn consume_entry,
void *cookie, struct task_struct *task,
struct pt_regs *regs)
@@ -113,4 +112,3 @@ noinline notrace void arch_stack_walk(st
break;
}
}
-#endif
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -216,8 +216,6 @@ void show_stack(struct task_struct *tsk,
barrier();
}

-#ifdef CONFIG_STACKTRACE
-
noinline notrace void arch_stack_walk(stack_trace_consume_fn consume_entry,
void *cookie, struct task_struct *task,
struct pt_regs *regs)
@@ -236,5 +234,3 @@ noinline notrace void arch_stack_walk(st

walk_stackframe(task, &frame, consume_entry, cookie);
}
-
-#endif
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -47,7 +47,7 @@ obj-y := cputable.o syscalls.o \
udbg.o misc.o io.o misc_$(BITS).o \
of_platform.o prom_parse.o firmware.o \
hw_breakpoint_constraints.o interrupt.o \
- kdebugfs.o
+ kdebugfs.o stacktrace.o
obj-y += ptrace/
obj-$(CONFIG_PPC64) += setup_64.o \
paca.o nvram_64.o note.o
@@ -116,7 +116,6 @@ obj-$(CONFIG_OPTPROBES) += optprobes.o
obj-$(CONFIG_KPROBES_ON_FTRACE) += kprobes-ftrace.o
obj-$(CONFIG_UPROBES) += uprobes.o
obj-$(CONFIG_PPC_UDBG_16550) += legacy_serial.o udbg_16550.o
-obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-$(CONFIG_SWIOTLB) += dma-swiotlb.o
obj-$(CONFIG_ARCH_HAS_DMA_SET_MASK) += dma-mask.o

--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -139,12 +139,8 @@ unsigned long __get_wchan(struct task_st
return pc;
}

-#ifdef CONFIG_STACKTRACE
-
noinline void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
struct task_struct *task, struct pt_regs *regs)
{
walk_stackframe(task, regs, consume_entry, cookie);
}
-
-#endif /* CONFIG_STACKTRACE */
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -40,7 +40,7 @@ obj-y += sysinfo.o lgr.o os_info.o machi
obj-y += runtime_instr.o cache.o fpu.o dumpstack.o guarded_storage.o sthyi.o
obj-y += entry.o reipl.o relocate_kernel.o kdebugfs.o alternative.o
obj-y += nospec-branch.o ipl_vmparm.o machine_kexec_reloc.o unwind_bc.o
-obj-y += smp.o text_amode31.o
+obj-y += smp.o text_amode31.o stacktrace.o

extra-y += head64.o vmlinux.lds

@@ -55,7 +55,6 @@ compat-obj-$(CONFIG_AUDIT) += compat_aud
obj-$(CONFIG_COMPAT) += compat_linux.o compat_signal.o
obj-$(CONFIG_COMPAT) += $(compat-obj-y)
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
-obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_KPROBES) += kprobes_insn_page.o
obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -84,7 +84,7 @@ obj-$(CONFIG_IA32_EMULATION) += tls.o
obj-y += step.o
obj-$(CONFIG_INTEL_TXT) += tboot.o
obj-$(CONFIG_ISA_DMA_API) += i8237.o
-obj-$(CONFIG_STACKTRACE) += stacktrace.o
+obj-y += stacktrace.o
obj-y += cpu/
obj-y += acpi/
obj-y += reboot.o
--- a/include/linux/stacktrace.h
+++ b/include/linux/stacktrace.h
@@ -8,21 +8,6 @@
struct task_struct;
struct pt_regs;

-#ifdef CONFIG_STACKTRACE
-void stack_trace_print(const unsigned long *trace, unsigned int nr_entries,
- int spaces);
-int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries,
- unsigned int nr_entries, int spaces);
-unsigned int stack_trace_save(unsigned long *store, unsigned int size,
- unsigned int skipnr);
-unsigned int stack_trace_save_tsk(struct task_struct *task,
- unsigned long *store, unsigned int size,
- unsigned int skipnr);
-unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
- unsigned int size, unsigned int skipnr);
-unsigned int stack_trace_save_user(unsigned long *store, unsigned int size);
-
-/* Internal interfaces. Do not use in generic code */
#ifdef CONFIG_ARCH_STACKWALK

/**
@@ -75,8 +60,24 @@ int arch_stack_walk_reliable(stack_trace

void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
const struct pt_regs *regs);
+#endif /* CONFIG_ARCH_STACKWALK */

-#else /* CONFIG_ARCH_STACKWALK */
+#ifdef CONFIG_STACKTRACE
+void stack_trace_print(const unsigned long *trace, unsigned int nr_entries,
+ int spaces);
+int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries,
+ unsigned int nr_entries, int spaces);
+unsigned int stack_trace_save(unsigned long *store, unsigned int size,
+ unsigned int skipnr);
+unsigned int stack_trace_save_tsk(struct task_struct *task,
+ unsigned long *store, unsigned int size,
+ unsigned int skipnr);
+unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
+ unsigned int size, unsigned int skipnr);
+unsigned int stack_trace_save_user(unsigned long *store, unsigned int size);
+
+#ifndef CONFIG_ARCH_STACKWALK
+/* Internal interfaces. Do not use in generic code */
struct stack_trace {
unsigned int nr_entries, max_entries;
unsigned long *entries;