linux_dsm_epyc7002/arch/parisc/kernel/stacktrace.c
Thomas Gleixner 4f3bd6ca31 parisc/stacktrace: Remove the pointless ULONG_MAX marker
Terminating the last trace entry with ULONG_MAX is a completely pointless
exercise and none of the consumers can rely on it because it's
inconsistently implemented across architectures. In fact quite some of the
callers remove the entry and adjust stack_trace.nr_entries afterwards.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Link: https://lkml.kernel.org/r/20190410103644.308534788@linutronix.de
2019-04-14 19:58:29 +02:00

46 lines
1.1 KiB
C

/*
* Stack trace management functions
*
* Copyright (C) 2009 Helge Deller <deller@gmx.de>
* based on arch/x86/kernel/stacktrace.c by Ingo Molnar <mingo@redhat.com>
* and parisc unwind functions by Randolph Chung <tausq@debian.org>
*
* TODO: Userspace stacktrace (CONFIG_USER_STACKTRACE_SUPPORT)
*/
#include <linux/module.h>
#include <linux/stacktrace.h>
#include <asm/unwind.h>
static void dump_trace(struct task_struct *task, struct stack_trace *trace)
{
struct unwind_frame_info info;
unwind_frame_init_task(&info, task, NULL);
/* unwind stack and save entries in stack_trace struct */
trace->nr_entries = 0;
while (trace->nr_entries < trace->max_entries) {
if (unwind_once(&info) < 0 || info.ip == 0)
break;
if (__kernel_text_address(info.ip))
trace->entries[trace->nr_entries++] = info.ip;
}
}
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
void save_stack_trace(struct stack_trace *trace)
{
dump_trace(current, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
dump_trace(tsk, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);