eBPF Linux tracepoints

configure.ac

@@ -129,6 +129,12 @@ AC_ARG_WITH([bdb],
   [use_bdb=$withval],
   [use_bdb=auto])
 
+AC_ARG_ENABLE([ebpf],
+  [AS_HELP_STRING([--enable-ebpf],
+  [enable eBPF tracing (default is yes if sys/sdt.h is found)])],
+  [use_ebpf=$enableval],
+  [use_ebpf=yes])
+
 AC_ARG_WITH([miniupnpc],
   [AS_HELP_STRING([--with-miniupnpc],
   [enable UPNP (default is yes if libminiupnpc is found)])],
@@ -1256,6 +1262,16 @@ if test x$enable_wallet != xno; then
     fi
 fi
 
+if test x$use_ebpf != xno; then
+  AC_CHECK_HEADER([sys/sdt.h], [have_sdt=yes], [have_sdt=no])
+else
+  have_sdt=no
+fi
+
+if test x$have_sdt = xyes; then
+  AC_DEFINE([ENABLE_TRACING], [1], [Define to 1 to enable eBPF user static defined tracepoints])
+fi
+
 dnl Check for libminiupnpc (optional)
 if test x$use_upnp != xno; then
   AC_CHECK_HEADERS(
@@ -1610,6 +1626,7 @@ AM_CONDITIONAL([TARGET_WINDOWS], [test x$TARGET_OS = xwindows])
 AM_CONDITIONAL([ENABLE_WALLET],[test x$enable_wallet = xyes])
 AM_CONDITIONAL([USE_SQLITE], [test "x$use_sqlite" = "xyes"])
 AM_CONDITIONAL([USE_BDB], [test "x$use_bdb" = "xyes"])
+AM_CONDITIONAL([ENABLE_TRACING],[test x$have_sdt = xyes])
 AM_CONDITIONAL([ENABLE_TESTS],[test x$BUILD_TEST = xyes])
 AM_CONDITIONAL([ENABLE_FUZZ],[test x$enable_fuzz = xyes])
 AM_CONDITIONAL([ENABLE_QT],[test x$bitcoin_enable_qt = xyes])
@@ -1768,6 +1785,7 @@ fi
 echo "  with bench    = $use_bench"
 echo "  with upnp     = $use_upnp"
 echo "  use asm       = $use_asm"
+echo "  ebpf tracing  = $have_sdt"
 echo "  sanitizers    = $use_sanitizers"
 echo "  debug enabled = $enable_debug"
 echo "  gprof enabled = $enable_gprof"

src/Makefile.am

@@ -235,6 +235,7 @@ BITCOIN_CORE_H = \
   util/system.h \
   util/threadnames.h \
   util/time.h \
+  util/trace.h \
   util/translation.h \
   util/ui_change_type.h \
   util/url.h \

src/util/trace.h

@@ -0,0 +1,45 @@
+// Copyright (c) 2020 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_UTIL_TRACE_H
+#define BITCOIN_UTIL_TRACE_H
+
+#ifdef ENABLE_TRACING
+
+#include <sys/sdt.h>
+
+#define TRACE(context, event) DTRACE_PROBE(context, event)
+#define TRACE1(context, event, a) DTRACE_PROBE1(context, event, a)
+#define TRACE2(context, event, a, b) DTRACE_PROBE2(context, event, a, b)
+#define TRACE3(context, event, a, b, c) DTRACE_PROBE3(context, event, a, b, c)
+#define TRACE4(context, event, a, b, c, d) DTRACE_PROBE4(context, event, a, b, c, d)
+#define TRACE5(context, event, a, b, c, d, e) DTRACE_PROBE5(context, event, a, b, c, d, e)
+#define TRACE6(context, event, a, b, c, d, e, f) DTRACE_PROBE6(context, event, a, b, c, d, e, f)
+#define TRACE7(context, event, a, b, c, d, e, f, g) DTRACE_PROBE7(context, event, a, b, c, d, e, f, g)
+#define TRACE8(context, event, a, b, c, d, e, f, g, h) DTRACE_PROBE8(context, event, a, b, c, d, e, f, g, h)
+#define TRACE9(context, event, a, b, c, d, e, f, g, h, i) DTRACE_PROBE9(context, event, a, b, c, d, e, f, g, h, i)
+#define TRACE10(context, event, a, b, c, d, e, f, g, h, i, j) DTRACE_PROBE10(context, event, a, b, c, d, e, f, g, h, i, j)
+#define TRACE11(context, event, a, b, c, d, e, f, g, h, i, j, k) DTRACE_PROBE11(context, event, a, b, c, d, e, f, g, h, i, j, k)
+#define TRACE12(context, event, a, b, c, d, e, f, g, h, i, j, k, l) DTRACE_PROBE12(context, event, a, b, c, d, e, f, g, h, i, j, k, l)
+
+#else
+
+#define TRACE(context, event)
+#define TRACE1(context, event, a)
+#define TRACE2(context, event, a, b)
+#define TRACE3(context, event, a, b, c)
+#define TRACE4(context, event, a, b, c, d)
+#define TRACE5(context, event, a, b, c, d, e)
+#define TRACE6(context, event, a, b, c, d, e, f)
+#define TRACE7(context, event, a, b, c, d, e, f, g)
+#define TRACE8(context, event, a, b, c, d, e, f, g, h)
+#define TRACE9(context, event, a, b, c, d, e, f, g, h, i)
+#define TRACE10(context, event, a, b, c, d, e, f, g, h, i, j)
+#define TRACE11(context, event, a, b, c, d, e, f, g, h, i, j, k)
+#define TRACE12(context, event, a, b, c, d, e, f, g, h, i, j, k, l)
+
+#endif
+
+
+#endif /* BITCOIN_UTIL_TRACE_H */