linux_dsm_epyc7002/arch/s390/oprofile/init.c
Martin Schwidefsky 78c98f9074 s390/unwind: introduce stack unwind API
Rework the dump_trace() stack unwinder interface to support different
unwinding algorithms. The new interface looks like this:

	struct unwind_state state;
	unwind_for_each_frame(&state, task, regs, start_stack)
		do_something(state.sp, state.ip, state.reliable);

The unwind_bc.c file contains the implementation for the classic
back-chain unwinder.

One positive side effect of the new code is it now handles ftraced
functions gracefully. It prints the real name of the return function
instead of 'return_to_handler'.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-05-02 13:54:11 +02:00

38 lines
850 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* S390 Version
* Copyright IBM Corp. 2002, 2011
* Author(s): Thomas Spatzier (tspat@de.ibm.com)
* Author(s): Mahesh Salgaonkar (mahesh@linux.vnet.ibm.com)
* Author(s): Heinz Graalfs (graalfs@linux.vnet.ibm.com)
* Author(s): Andreas Krebbel (krebbel@linux.vnet.ibm.com)
*
* @remark Copyright 2002-2011 OProfile authors
*/
#include <linux/oprofile.h>
#include <linux/init.h>
#include <asm/processor.h>
#include <asm/unwind.h>
static void s390_backtrace(struct pt_regs *regs, unsigned int depth)
{
struct unwind_state state;
unwind_for_each_frame(&state, current, regs, 0) {
if (depth-- == 0)
break;
oprofile_add_trace(state.ip);
}
}
int __init oprofile_arch_init(struct oprofile_operations *ops)
{
ops->backtrace = s390_backtrace;
return 0;
}
void oprofile_arch_exit(void)
{
}