2019-11-12 22:48:34

by Max Filippov

Subject: [PATCH v3 0/2] xtensa: improve stack dumping

Hello,

this series cleans up code around stack_dump and makes dump size
configurable.

Changes v2->v3:
- split Kconfig change into separate patch
- use symbolic names instead of hardcoded numbers

Changes v1->v2:
- use print_hex_dump.

Max Filippov (2):
xtensa: improve stack dumping
xtensa: make stack dump size configurable

arch/xtensa/Kconfig.debug | 7 +++++++
arch/xtensa/kernel/traps.c | 27 +++++++++++----------------
2 files changed, 18 insertions(+), 16 deletions(-)

--
2.20.1

2019-11-12 22:48:38

by Max Filippov

Subject: [PATCH v3 1/2] xtensa: improve stack dumping

Calculate printable stack size and use print_hex_dump instead of
opencoding it.
Drop extra newline output in show_trace as its output format does not
depend on CONFIG_KALLSYMS.

Reviewed-by: Petr Mladek <[email protected]>
Signed-off-by: Max Filippov <[email protected]>
---
Changes v2->v3:
- split Kconfig change into separate patch
- use symbolic names instead of hardcoded numbers

Changes v1->v2:
- use print_hex_dump.

arch/xtensa/kernel/traps.c | 27 +++++++++++----------------
1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 4a6c495ce9b6..be26ec6c0e0e 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -491,32 +491,27 @@ void show_trace(struct task_struct *task, unsigned long *sp)

pr_info("Call Trace:\n");
walk_stackframe(sp, show_trace_cb, NULL);
-#ifndef CONFIG_KALLSYMS
- pr_cont("\n");
-#endif
}

-static int kstack_depth_to_print = 24;
+#define STACK_DUMP_ENTRY_SIZE 4
+#define STACK_DUMP_LINE_SIZE 32
+static size_t kstack_depth_to_print = 24;

void show_stack(struct task_struct *task, unsigned long *sp)
{
- int i = 0;
- unsigned long *stack;
+ size_t len;

if (!sp)
sp = stack_pointer(task);
- stack = sp;

- pr_info("Stack:\n");
+ len = min((-(size_t)sp) & (THREAD_SIZE - STACK_DUMP_ENTRY_SIZE),
+ kstack_depth_to_print * STACK_DUMP_ENTRY_SIZE);

- for (i = 0; i < kstack_depth_to_print; i++) {
- if (kstack_end(sp))
- break;
- pr_cont(" %08lx", *sp++);
- if (i % 8 == 7)
- pr_cont("\n");
- }
- show_trace(task, stack);
+ pr_info("Stack:\n");
+ print_hex_dump(KERN_INFO, " ", DUMP_PREFIX_NONE,
+ STACK_DUMP_LINE_SIZE, STACK_DUMP_ENTRY_SIZE,
+ sp, len, false);
+ show_trace(task, sp);
}

DEFINE_SPINLOCK(die_lock);
--
2.20.1