drivers/staging/android/fiq_debugger/fiq_watchdog.c

   1 /*
   2  * Copyright (C) 2014 Google, Inc.
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/pstore_ram.h>
  18
  19 #include "fiq_watchdog.h"
  20 #include "fiq_debugger_priv.h"
  21
  22 static DEFINE_RAW_SPINLOCK(fiq_watchdog_lock);
  23
  24 static void fiq_watchdog_printf(struct fiq_debugger_output *output,
  25                                 const char *fmt, ...)
  26 {
  27         char buf[256];
  28         va_list ap;
  29         int len;
  30
  31         va_start(ap, fmt);
  32         len = vscnprintf(buf, sizeof(buf), fmt, ap);
  33         va_end(ap);
  34
  35         ramoops_console_write_buf(buf, len);
  36 }
  37
  38 struct fiq_debugger_output fiq_watchdog_output = {
  39         .printf = fiq_watchdog_printf,
  40 };
  41
  42 void fiq_watchdog_triggered(const struct pt_regs *regs, void *svc_sp)
  43 {
  44         char msg[24];
  45         int len;
  46
  47         raw_spin_lock(&fiq_watchdog_lock);
  48
  49         len = scnprintf(msg, sizeof(msg), "watchdog fiq cpu %d\n",
  50                         THREAD_INFO(svc_sp)->cpu);
  51         ramoops_console_write_buf(msg, len);
  52
  53         fiq_debugger_dump_stacktrace(&fiq_watchdog_output, regs, 100, svc_sp);
  54
  55         raw_spin_unlock(&fiq_watchdog_lock);
  56 }