s390/kernel/trace.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Tracepoint definitions for s390
0004  *
0005  * Copyright IBM Corp. 2015
0006  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
0007  */
0008
0009 #include <linux/percpu.h>
0010 #define CREATE_TRACE_POINTS
0011 #include <asm/trace/diag.h>
0012
0013 EXPORT_TRACEPOINT_SYMBOL(s390_diagnose);
0014
0015 static DEFINE_PER_CPU(unsigned int, diagnose_trace_depth);
0016
0017 void notrace trace_s390_diagnose_norecursion(int diag_nr)
0018 {
0019     unsigned long flags;
0020     unsigned int *depth;
0021
0022     /* Avoid lockdep recursion. */
0023     if (IS_ENABLED(CONFIG_LOCKDEP))
0024         return;
0025     local_irq_save(flags);
0026     depth = this_cpu_ptr(&diagnose_trace_depth);
0027     if (*depth == 0) {
0028         (*depth)++;
0029         trace_s390_diagnose(diag_nr);
0030         (*depth)--;
0031     }
0032     local_irq_restore(flags);
0033 }