LXR linux/arch/s390/kernel/trace.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Tracepoint definitions for s390
   4 *
   5 * Copyright IBM Corp. 2015
   6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   7 */
   8
   9#include <linux/percpu.h>
  10#define CREATE_TRACE_POINTS
  11#include <asm/trace/diag.h>
  12
  13EXPORT_TRACEPOINT_SYMBOL(s390_diagnose);
  14
  15static DEFINE_PER_CPU(unsigned int, diagnose_trace_depth);
  16
  17void notrace trace_s390_diagnose_norecursion(int diag_nr)
  18{
  19        unsigned long flags;
  20        unsigned int *depth;
  21
  22        /* Avoid lockdep recursion. */
  23        if (IS_ENABLED(CONFIG_LOCKDEP))
  24                return;
  25        local_irq_save(flags);
  26        depth = this_cpu_ptr(&diagnose_trace_depth);
  27        if (*depth == 0) {
  28                (*depth)++;
  29                trace_s390_diagnose(diag_nr);
  30                (*depth)--;
  31        }
  32        local_irq_restore(flags);
  33}
  34