mirror of
https://github.com/torvalds/linux.git
synced 2024-11-18 01:51:53 +00:00
d2912cb15b
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
68 lines
1.7 KiB
C
68 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Linux performance counter support for MIPS.
|
|
*
|
|
* Copyright (C) 2010 MIPS Technologies, Inc.
|
|
* Author: Deng-Cheng Zhu
|
|
*
|
|
* This code is based on the implementation for ARM, which is in turn
|
|
* based on the sparc64 perf event code and the x86 code. Performance
|
|
* counter access is based on the MIPS Oprofile code. And the callchain
|
|
* support references the code of MIPS stacktrace.c.
|
|
*/
|
|
|
|
#include <linux/perf_event.h>
|
|
#include <linux/sched/task_stack.h>
|
|
|
|
#include <asm/stacktrace.h>
|
|
|
|
/* Callchain handling code. */
|
|
|
|
/*
|
|
* Leave userspace callchain empty for now. When we find a way to trace
|
|
* the user stack callchains, we will add it here.
|
|
*/
|
|
|
|
static void save_raw_perf_callchain(struct perf_callchain_entry_ctx *entry,
|
|
unsigned long reg29)
|
|
{
|
|
unsigned long *sp = (unsigned long *)reg29;
|
|
unsigned long addr;
|
|
|
|
while (!kstack_end(sp)) {
|
|
addr = *sp++;
|
|
if (__kernel_text_address(addr)) {
|
|
perf_callchain_store(entry, addr);
|
|
if (entry->nr >= entry->max_stack)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
|
|
struct pt_regs *regs)
|
|
{
|
|
unsigned long sp = regs->regs[29];
|
|
#ifdef CONFIG_KALLSYMS
|
|
unsigned long ra = regs->regs[31];
|
|
unsigned long pc = regs->cp0_epc;
|
|
|
|
if (raw_show_trace || !__kernel_text_address(pc)) {
|
|
unsigned long stack_page =
|
|
(unsigned long)task_stack_page(current);
|
|
if (stack_page && sp >= stack_page &&
|
|
sp <= stack_page + THREAD_SIZE - 32)
|
|
save_raw_perf_callchain(entry, sp);
|
|
return;
|
|
}
|
|
do {
|
|
perf_callchain_store(entry, pc);
|
|
if (entry->nr >= entry->max_stack)
|
|
break;
|
|
pc = unwind_stack(current, &sp, pc, &ra);
|
|
} while (pc);
|
|
#else
|
|
save_raw_perf_callchain(entry, sp);
|
|
#endif
|
|
}
|