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Diffstat (limited to '')
| -rw-r--r-- | lib/trace.h | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/lib/trace.h b/lib/trace.h new file mode 100644 index 0000000..73fc10a --- /dev/null +++ b/lib/trace.h @@ -0,0 +1,80 @@ +/* Tracing macros + * + * Wraps tracepoint macros for different tracing systems to allow switching + * between them at compile time. + * + * This should not be included directly by source files wishing to provide + * tracepoints. Instead, write a header that defines LTTng tracepoints and + * which includes this header, and include your new header in your source. USDT + * probes do not need tracepoint definitions, but are less capable than LTTng + * tracepoints. + * + * Copyright (C) 2020 NVIDIA Corporation + * Quentin Young + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; see the file COPYING; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef _TRACE_H_ +#define _TRACE_H_ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif /* HAVE_CONFIG_H */ + +/* + * Provided here: + * - frrtrace(n, provider, name, ...args...) + * - frrtrace_enabled(provider, name) + * - frrtracelog(level, msg, ...) + * + * Use frrtrace() to define tracepoints. n is the number of arguments; this is + * needed because USDT probe definitions use DTRACE_PROBEn macros, so the + * number of args must be passed in order to expand the correct macro. + * + * frrtrace_enabled() maps to tracepoint_enabled() under LTTng and is always + * true when using USDT. In the future it could be mapped to USDT semaphores + * but this is not implemented at present. + * + * frrtracelog() maps to tracelog() under LTTng and should only be used in zlog + * core code, to propagate zlog messages to LTTng. It expands to nothing + * otherwise. + */ + +#if defined(HAVE_LTTNG) + +#define frrtrace(nargs, provider, name, ...) \ + tracepoint(provider, name, ## __VA_ARGS__) +#define frrtrace_enabled(...) tracepoint_enabled(__VA_ARGS__) +#define frrtracelog(...) tracelog(__VA_ARGS__) + +#elif defined(HAVE_USDT) + +#include "sys/sdt.h" + +#define frrtrace(nargs, provider, name, ...) \ + DTRACE_PROBE##nargs(provider, name, ## __VA_ARGS__) +#define frrtrace_enabled(...) true +#define frrtracelog(...) + +#else + +#define frrtrace(nargs, provider, name, ...) (void)0 +#define frrtrace_enabled(...) false +#define frrtracelog(...) (void)0 + +#endif + +#endif /* _TRACE_H_ */ |