Files
android_kernel_xiaomi_sm8450/arch/riscv/kernel/stacktrace.c
Linus Torvalds b0bb1269b9 Merge tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V updates from Palmer Dabbelt:
 "This contains an assortment of RISC-V related patches that I'd like to
  target for the 5.2 merge window. Most of the patches are cleanups, but
  there are a handful of user-visible changes:

   - The nosmp and nr_cpus command-line arguments are now supported,
     which work like normal.

   - The SBI console no longer installs itself as a preferred console,
     we rely on standard mechanisms (/chosen, command-line, hueristics)
     instead.

   - sfence_remove_sfence_vma{,_asid} now pass their arguments along to
     the SBI call.

   - Modules now support BUG().

   - A missing sfence.vma during boot has been added. This bug only
     manifests during boot.

   - The arch/riscv support for SiFive's L2 cache controller has been
     merged, which should un-block the EDAC framework work.

  I've only tested this on QEMU again, as I didn't have time to get
  things running on the Unleashed. The latest master from this morning
  merges in cleanly and passes the tests as well"

* tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (31 commits)
  riscv: fix locking violation in page fault handler
  RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs
  RISC-V: Add DT documentation for SiFive L2 Cache Controller
  RISC-V: Avoid using invalid intermediate translations
  riscv: Support BUG() in kernel module
  riscv: Add the support for c.ebreak check in is_valid_bugaddr()
  riscv: support trap-based WARN()
  riscv: fix sbi_remote_sfence_vma{,_asid}.
  riscv: move switch_mm to its own file
  riscv: move flush_icache_{all,mm} to cacheflush.c
  tty: Don't force RISCV SBI console as preferred console
  RISC-V: Access CSRs using CSR numbers
  RISC-V: Add interrupt related SCAUSE defines in asm/csr.h
  RISC-V: Use tabs to align macro values in asm/csr.h
  RISC-V: Fix minor checkpatch issues.
  RISC-V: Support nr_cpus command line option.
  RISC-V: Implement nosmp commandline option.
  RISC-V: Add RISC-V specific arch_match_cpu_phys_id
  riscv: vdso: drop unnecessary cc-ldoption
  riscv: call pm_power_off from machine_halt / machine_power_off
  ...
2019-05-19 09:56:36 -07:00

178 lines
4.1 KiB
C

/*
* Copyright (C) 2008 ARM Limited
* Copyright (C) 2014 Regents of the University of California
*
* 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 distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/export.h>
#include <linux/kallsyms.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
#include <linux/stacktrace.h>
#include <linux/ftrace.h>
#ifdef CONFIG_FRAME_POINTER
struct stackframe {
unsigned long fp;
unsigned long ra;
};
static void notrace walk_stackframe(struct task_struct *task,
struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
{
unsigned long fp, sp, pc;
if (regs) {
fp = frame_pointer(regs);
sp = user_stack_pointer(regs);
pc = instruction_pointer(regs);
} else if (task == NULL || task == current) {
const register unsigned long current_sp __asm__ ("sp");
fp = (unsigned long)__builtin_frame_address(0);
sp = current_sp;
pc = (unsigned long)walk_stackframe;
} else {
/* task blocked in __switch_to */
fp = task->thread.s[0];
sp = task->thread.sp;
pc = task->thread.ra;
}
for (;;) {
unsigned long low, high;
struct stackframe *frame;
if (unlikely(!__kernel_text_address(pc) || fn(pc, arg)))
break;
/* Validate frame pointer */
low = sp + sizeof(struct stackframe);
high = ALIGN(sp, THREAD_SIZE);
if (unlikely(fp < low || fp > high || fp & 0x7))
break;
/* Unwind stack frame */
frame = (struct stackframe *)fp - 1;
sp = fp;
fp = frame->fp;
pc = ftrace_graph_ret_addr(current, NULL, frame->ra,
(unsigned long *)(fp - 8));
}
}
#else /* !CONFIG_FRAME_POINTER */
static void notrace walk_stackframe(struct task_struct *task,
struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
{
unsigned long sp, pc;
unsigned long *ksp;
if (regs) {
sp = user_stack_pointer(regs);
pc = instruction_pointer(regs);
} else if (task == NULL || task == current) {
const register unsigned long current_sp __asm__ ("sp");
sp = current_sp;
pc = (unsigned long)walk_stackframe;
} else {
/* task blocked in __switch_to */
sp = task->thread.sp;
pc = task->thread.ra;
}
if (unlikely(sp & 0x7))
return;
ksp = (unsigned long *)sp;
while (!kstack_end(ksp)) {
if (__kernel_text_address(pc) && unlikely(fn(pc, arg)))
break;
pc = (*ksp++) - 0x4;
}
}
#endif /* CONFIG_FRAME_POINTER */
static bool print_trace_address(unsigned long pc, void *arg)
{
print_ip_sym(pc);
return false;
}
void show_stack(struct task_struct *task, unsigned long *sp)
{
pr_cont("Call Trace:\n");
walk_stackframe(task, NULL, print_trace_address, NULL);
}
static bool save_wchan(unsigned long pc, void *arg)
{
if (!in_sched_functions(pc)) {
unsigned long *p = arg;
*p = pc;
return true;
}
return false;
}
unsigned long get_wchan(struct task_struct *task)
{
unsigned long pc = 0;
if (likely(task && task != current && task->state != TASK_RUNNING))
walk_stackframe(task, NULL, save_wchan, &pc);
return pc;
}
#ifdef CONFIG_STACKTRACE
static bool __save_trace(unsigned long pc, void *arg, bool nosched)
{
struct stack_trace *trace = arg;
if (unlikely(nosched && in_sched_functions(pc)))
return false;
if (unlikely(trace->skip > 0)) {
trace->skip--;
return false;
}
trace->entries[trace->nr_entries++] = pc;
return (trace->nr_entries >= trace->max_entries);
}
static bool save_trace(unsigned long pc, void *arg)
{
return __save_trace(pc, arg, false);
}
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
walk_stackframe(tsk, NULL, save_trace, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
void save_stack_trace(struct stack_trace *trace)
{
save_stack_trace_tsk(NULL, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
#endif /* CONFIG_STACKTRACE */