ircd::allocator: Add interface to fetch some resource limits.

include/ircd/allocator.h

@@ -28,6 +28,10 @@ namespace ircd::allocator
 	template<class T = char, size_t L0_SIZE = 512> struct twolevel;
 	template<class T> struct node;
 
+	size_t rlimit_as();
+	size_t rlimit_data();
+	size_t rlimit_memlock();
+
 	std::unique_ptr<char, decltype(&std::free)>
 	aligned_alloc(const size_t &align, const size_t &size);
 

ircd/allocator.cc

@@ -8,6 +8,8 @@
 // copyright notice and this permission notice is present in all copies. The
 // full license for this software is available in the LICENSE file.
 
+#include <RB_INC_SYS_RESOURCE_H
+
 // Uncomment or -D this #define to enable our own crude but simple ability to
 // profile dynamic memory usage. Global `new` and `delete` will be captured
 // here by this definition file into thread_local counters accessible via
@@ -295,6 +297,62 @@ ircd::allocator::aligned_alloc(const size_t &alignment_,
 	};
 }
 
+//
+// resource limits
+//
+
+#if defined(HAVE_SYS_RESOURCE_H) && defined(RLIMIT_MEMLOCK)
+size_t
+ircd::allocator::rlimit_memlock()
+{
+	rlimit rlim;
+	syscall(getrlimit, RLIMIT_MEMLOCK, &rlim);
+	return rlim.rlim_cur;
+}
+#else
+size_t
+ircd::allocator::rlimit_memlock()
+{
+	return 0;
+}
+#endif
+
+#if defined(HAVE_SYS_RESOURCE_H) && defined(RLIMIT_DATA)
+size_t
+ircd::allocator::rlimit_data()
+{
+	rlimit rlim;
+	syscall(getrlimit, RLIMIT_DATA, &rlim);
+	return rlim.rlim_cur;
+}
+#else
+size_t
+ircd::allocator::rlimit_data()
+{
+	return 0;
+}
+#endif
+
+#if defined(HAVE_SYS_RESOURCE_H) && defined(RLIMIT_AS)
+size_t
+ircd::allocator::rlimit_as()
+{
+	rlimit rlim;
+	syscall(getrlimit, RLIMIT_AS, &rlim);
+	return rlim.rlim_cur;
+}
+#else
+size_t
+ircd::allocator::rlimit_as()
+{
+	return 0;
+}
+#endif
+
+//
+// Developer profiling
+//
+
 #ifdef RB_PROF_ALLOC // --------------------------------------------------
 
 void *