MINOR: trace: start to create a new trace subsystem

The principle of this subsystem will be to support taking live traces
at various places in the code with conditional triggers, filters, and
ability to lock on some elements. The traces will support typed events
and will be sent into sinks made of ring buffers, file descriptors or
remote servers.

diff --git a/Makefile b/Makefile
index 9bc94f8abd8e3a984e619abbf3afeb63929f7468..ddddb44f2e7137d6f9910a4e9f8e6df623da5ea4 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -775,7 +775,7 @@ OBJS = src/http_ana.o src/cfgparse-listen.o src/stream.o                      \
        src/http.o src/hpack-dec.o src/action.o src/proto_udp.o src/http_acl.o \
        src/xxhash.o src/hpack-enc.o src/h2.o src/freq_ctr.o src/lru.o         \
        src/protocol.o src/arg.o src/hpack-huff.o src/base64.o                 \
-       src/hash.o src/mailers.o src/activity.o src/version.o                  \
+       src/hash.o src/mailers.o src/activity.o src/version.o src/trace.o      \
        src/mworker.o src/mworker-prog.o src/debug.o src/wdt.o src/dict.o      \
        src/xprt_handshake.o
 

diff --git a/include/proto/trace.h b/include/proto/trace.h
new file mode 100644 (file)
index 0000000..0838551
--- /dev/null
+++ b/include/proto/trace.h
@@ -0,0 +1,58 @@
+/*
+ * include/proto/trace.h
+ * This file provides functions for runtime tracing
+ *
+ * Copyright (C) 2000-2019 Willy Tarreau - w@1wt.eu
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation, version 2.1
+ * exclusively.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef _PROTO_TRACE_H
+#define _PROTO_TRACE_H
+
+#include <common/buffer.h>
+#include <common/compat.h>
+#include <common/config.h>
+#include <common/ist.h>
+#include <common/mini-clist.h>
+#include <types/log.h>
+#include <types/sink.h>
+#include <types/trace.h>
+
+extern struct list trace_sources;
+
+/* registers trace source <source>. Modifies the list element!
+ * The {start,pause,stop,report} events are not changed so the source may
+ * preset them.
+ */
+static inline void trace_register_source(struct trace_source *source)
+{
+       source->lockon = TRACE_LOCKON_NOTHING;
+       source->level = TRACE_LEVEL_USER;
+       source->detail_level = LOG_NOTICE;
+       source->sink = NULL;
+       source->state = TRACE_STATE_STOPPED;
+       source->lockon_ptr = NULL;
+       LIST_ADDQ(&trace_sources, &source->source_link);
+}
+
+#endif /* _PROTO_TRACE_H */
+
+/*
+ * Local variables:
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ * End:
+ */

diff --git a/include/types/trace.h b/include/types/trace.h
new file mode 100644 (file)
index 0000000..65a79aa
--- /dev/null
+++ b/include/types/trace.h
@@ -0,0 +1,97 @@
+/*
+ * include/types/trace.h
+ * This file provides definitions for runtime tracing
+ *
+ * Copyright (C) 2000-2019 Willy Tarreau - w@1wt.eu
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation, version 2.1
+ * exclusively.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef _TYPES_TRACE_H
+#define _TYPES_TRACE_H
+
+#include <common/buffer.h>
+#include <common/compat.h>
+#include <common/config.h>
+#include <common/ist.h>
+#include <common/mini-clist.h>
+#include <types/sink.h>
+
+enum trace_state {
+       TRACE_STATE_STOPPED = 0,  // completely disabled
+       TRACE_STATE_WAITING,      // waiting for the start condition to happen
+       TRACE_STATE_RUNNING,      // waiting for the stop or pause conditions
+};
+
+enum trace_level {
+       TRACE_LEVEL_USER = 0,     // info useful to the end user
+       TRACE_LEVEL_PAYLOAD,      // add info relevant to the payload
+       TRACE_LEVEL_PROTO,        // add info relevant to the protocol
+       TRACE_LEVEL_STATE,        // add info relevant to the state machine
+       TRACE_LEVEL_DEVELOPER,    // add info useful only to the developer
+};
+
+enum trace_lockon {
+       TRACE_LOCKON_NOTHING = 0, // don't lock on anything
+       TRACE_LOCKON_THREAD,      // lock on the thread that started the trace
+       TRACE_LOCKON_LISTENER,    // lock on the listener that started the trace
+       TRACE_LOCKON_FRONTEND,    // lock on the frontend that started the trace
+       TRACE_LOCKON_BACKEND,     // lock on the backend that started the trace
+       TRACE_LOCKON_SERVER,      // lock on the server that started the trace
+       TRACE_LOCKON_CONNECTION,  // lock on the connection that started the trace
+       TRACE_LOCKON_SESSION,     // lock on the session that started the trace
+       TRACE_LOCKON_STREAM,      // lock on the stream that started the trace
+};
+
+/* Each trace event maps a name to a mask in an uint64_t. Multiple bits are
+ * permitted to have composite events. This is supposed to be stored into an
+ * array terminated by mask 0 (name and desc are then ignored). Names "now",
+ * "any" and "none" are reserved by the CLI parser for start/pause/stop
+ * operations..
+ */
+struct trace_event {
+       uint64_t mask;
+       const char *name;
+       const char *desc;
+};
+
+struct trace_source {
+       /* source definition */
+       const struct ist name;
+       const char *desc;
+       const struct trace_event *known_events;
+       struct list source_link; // element in list of known trace sources
+       /* trace configuration, adjusted by "trace <module>" on CLI */
+       enum trace_lockon lockon;
+       uint64_t start_events;   // what will start the trace. default: 0=nothing
+       uint64_t pause_events;   // what will pause the trace. default: 0=nothing
+       uint64_t stop_events;    // what will stop the trace. default: 0=nothing
+       uint64_t report_events;  // mask of which events need to be reported.
+       enum trace_level level;  // report traces up to this level of info
+       int detail_level;        // report events with this level of detail (LOG_*)
+       struct sink *sink;       // where to send the trace
+       /* trace state part below */
+       enum trace_state state;
+       void *lockon_ptr;        // what to lockon when lockon is set
+};
+
+#endif /* _TYPES_TRACE_H */
+
+/*
+ * Local variables:
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ * End:
+ */

diff --git a/src/trace.c b/src/trace.c
new file mode 100644 (file)
index 0000000..97bd1b5
--- /dev/null
+++ b/src/trace.c
@@ -0,0 +1,36 @@
+/*
+ * Runtime tracing API
+ *
+ * Copyright (C) 2000-2019 Willy Tarreau - w@1wt.eu
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation, version 2.1
+ * exclusively.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <common/buffer.h>
+#include <common/compat.h>
+#include <common/config.h>
+#include <common/ist.h>
+#include <common/mini-clist.h>
+#include <proto/log.h>
+#include <proto/trace.h>
+
+struct list trace_sources = LIST_HEAD_INIT(trace_sources);
+
+/*
+ * Local variables:
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ * End:
+ */