From f6bc11b76ac7155508b933f28a997ebfe8b97079 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Fri, 16 Oct 2020 09:48:33 -0700
Subject: [PATCH] ircd::vg: Add stack register/deregister to interface.

ircd::vg: Use extern const bool for active(); minor reorg.
---
 include/ircd/vg.h    |  8 +++++++-
 ircd/Makefile.am     |  2 +-
 ircd/db_allocator.cc |  2 +-
 ircd/info.cc         |  4 ++--
 ircd/vg.cc           | 29 ++++++++++++++++++++++++++---
 modules/console.cc   |  2 +-
 6 files changed, 38 insertions(+), 9 deletions(-)

diff --git a/include/ircd/vg.h b/include/ircd/vg.h
index 3b1009d9e..be81c3fd4 100644
--- a/include/ircd/vg.h
+++ b/include/ircd/vg.h
@@ -14,7 +14,7 @@
 /// Valgrind memcheck hypercall suite
 namespace ircd::vg
 {
-	bool active() noexcept;
+	extern const bool active;
 	size_t errors() noexcept;
 
 	bool defined(const const_buffer &) noexcept;
@@ -22,3 +22,9 @@ namespace ircd::vg
 	void set_undefined(const const_buffer &) noexcept;
 	void set_noaccess(const const_buffer &) noexcept;
 }
+
+namespace ircd::vg::stack
+{
+	uint add(const mutable_buffer &) noexcept;
+	void del(const uint &id) noexcept;
+}
diff --git a/ircd/Makefile.am b/ircd/Makefile.am
index 3ea4fd58e..b9826364f 100644
--- a/ircd/Makefile.am
+++ b/ircd/Makefile.am
@@ -121,10 +121,10 @@ libircd_la_LIBADD = \
 libircd_la_SOURCES =#
 libircd_la_SOURCES += assert.cc
 libircd_la_SOURCES += info.cc
+libircd_la_SOURCES += vg.cc
 libircd_la_SOURCES += allocator.cc
 libircd_la_SOURCES += allocator_gnu.cc
 libircd_la_SOURCES += allocator_je.cc
-libircd_la_SOURCES += vg.cc
 libircd_la_SOURCES += exception.cc
 libircd_la_SOURCES += util.cc
 libircd_la_SOURCES += demangle.cc
diff --git a/ircd/db_allocator.cc b/ircd/db_allocator.cc
index 546f4609f..687546e63 100644
--- a/ircd/db_allocator.cc
+++ b/ircd/db_allocator.cc
@@ -70,7 +70,7 @@ ircd::db::database::allocator::mlock_enabled
 	mlock_limit == -1UL
 
 	// mlock2() not supported by valgrind
-	&& !vg::active()
+	&& !vg::active
 };
 
 decltype(ircd::db::database::allocator::mlock_current)
diff --git a/ircd/info.cc b/ircd/info.cc
index 1cdc65fbc..ad7137d0d 100644
--- a/ircd/info.cc
+++ b/ircd/info.cc
@@ -283,8 +283,8 @@ ircd::info::dump_cpu_info_x86()
 		hardware::virtualized?
 			"virtual"_sv:
 			"physical"_sv,
-		vg::active()?
-			" valgrind "_sv:
+		vg::active?
+			" valgrind"_sv:
 			""_sv,
 		support,
 	};
diff --git a/ircd/vg.cc b/ircd/vg.cc
index 009c2872a..d63a3bd12 100644
--- a/ircd/vg.cc
+++ b/ircd/vg.cc
@@ -61,15 +61,38 @@ noexcept
 	#endif
 }
 
-bool
-ircd::vg::active()
-noexcept
+decltype(ircd::vg::active)
+ircd::vg::active{[]() -> bool
 {
 	#ifdef HAVE_VALGRIND_VALGRIND_H
 	return RUNNING_ON_VALGRIND;
 	#else
 	return false;
 	#endif
+}()};
+
+//
+// vg::stack
+//
+
+void
+ircd::vg::stack::del(const uint &id)
+noexcept
+{
+	#ifdef HAVE_VALGRIND_MEMCHECK_H
+	VALGRIND_STACK_DEREGISTER(id);
+	#endif
+}
+
+uint
+ircd::vg::stack::add(const mutable_buffer &buf)
+noexcept
+{
+	#ifdef HAVE_VALGRIND_MEMCHECK_H
+	return VALGRIND_STACK_REGISTER(ircd::data(buf) + ircd::size(buf), ircd::data(buf));
+	#else
+	return 0;
+	#endif
 }
 
 ///////////////////////////////////////////////////////////////////////////////
diff --git a/modules/console.cc b/modules/console.cc
index 63640dce0..68b43a226 100644
--- a/modules/console.cc
+++ b/modules/console.cc
@@ -1339,7 +1339,7 @@ console_cmd__mem__get(opt &out, const string_view &line)
 bool
 console_cmd__vg(opt &out, const string_view &line)
 {
-	if(vg::active())
+	if(vg::active)
 		out << "running on valgrind" << std::endl;
 	else
 		out << "bare metal" << std::endl;