memory: add new mmap allocator

include/villas/memory_type.h

@@ -53,7 +53,8 @@ struct memory_type {
 };
 
 extern struct memory_type memory_heap;
-extern struct memory_type memory_hugepage;
+extern struct memory_type memory_mmap;
+extern struct memory_type memory_mmap_hugetlb;
 extern struct memory_type *memory_default;
 
 struct memory_type * memory_ib(struct node *n, struct memory_type *parent);

lib/CMakeLists.txt

@@ -45,8 +45,8 @@ set(LIB_SRC
     mapping.cpp
     memory.cpp
     memory/heap.cpp
-    memory/hugepage.cpp
     memory/managed.cpp
+    memory/mmap.cpp
     node_direction.cpp
     node_type.cpp
     node.cpp

lib/memory.cpp

@@ -44,10 +44,19 @@ int memory_init(int hugepages)
 
 	info("Initialize memory sub-system: #hugepages=%d", hugepages);
 
+	if (hugepages > 0) {
 		ret = memory_hugepage_init(hugepages);
 		if (ret)
 			return ret;
 
+		memory_default = &memory_mmap_hugetlb;
+	}
+	else {
+		memory_default = &memory_mmap;
+
+		warning("Hugepage allocator disabled.");
+	}
+
 	size_t lock = kernel_get_hugepage_size() * hugepages;
 
 	ret = memory_lock(lock);

lib/memory/hugepage.cpp → lib/memory/mmap.cpp

-/** Hugepage memory allocator.
+/** mmap memory allocator.
  *
  * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
  * @copyright 2014-2019, Institute for Automation of Complex Power Systems, EONERC
@@ -74,11 +74,9 @@ int memory_hugepage_init(int hugepages)
 	return 0;
 }
 
-/** Allocate memory backed by hugepages with malloc() like interface */
-static struct memory_allocation * memory_hugepage_alloc(struct memory_type *m, size_t len, size_t alignment)
+/** Allocate memory backed by mmaps with malloc() like interface */
+static struct memory_allocation * memory_mmap_alloc(size_t len, size_t alignment, struct memory_type *m)
 {
-	static bool use_huge = true;
-
 	int flags, fd;
 	size_t sz;
 
@@ -86,7 +84,7 @@ static struct memory_allocation * memory_hugepage_alloc(struct memory_type *m, s
 	if (!ma)
 		return nullptr;
 
-retry:	if (use_huge) {
+	if (m->flags & (int) MemoryFlags::HUGEPAGE) {
 #ifdef __linux__
 		flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB;
 #else
@@ -99,15 +97,19 @@ retry:	if (use_huge) {
 		fd = -1;
 #endif
 		sz = hugepgsz;
+
+		info("allocate %#zx bytes mmap_hugetlb memory", len);
 	}
 	else {
 		flags = MAP_PRIVATE | MAP_ANONYMOUS;
 		fd = -1;
 
 		sz = pgsz;
+
+		info("allocate %#zx bytes mmap memory", len);
 	}
 
-	/** We must make sure that len is a multiple of the (huge)page size
+	/** We must make sure that len is a multiple of the page size
 	 *
 	 * See: https://lkml.org/lkml/2014/10/22/925
 	 */
@@ -117,21 +119,14 @@ retry:	if (use_huge) {
 
 	ma->address = mmap(nullptr, ma->length, PROT_READ | PROT_WRITE, flags, fd, 0);
 	if (ma->address == MAP_FAILED) {
-		if (use_huge) {
-			warning("Failed to map hugepages, try with normal pages instead!");
-			use_huge = false;
-			goto retry;
-		}
-		else {
-			free(ma);
-			return nullptr;
-		}
+		free(ma);
+		return nullptr;
 	}
 
 	return ma;
 }
 
-static int memory_hugepage_free(struct memory_type *m, struct memory_allocation *ma)
+static int memory_mmap_free(struct memory_allocation *ma, struct memory_type *m)
 {
 	int ret;
 
@@ -142,10 +137,18 @@ static int memory_hugepage_free(struct memory_type *m, struct memory_allocation
 	return 0;
 }
 
-struct memory_type memory_hugepage = {
-	.name = "mmap_hugepages",
+struct memory_type memory_mmap = {
+	.name = "mmap",
+	.flags = (int) MemoryFlags::MMAP,
+	.alignment = 12, /* 4k page */
+	.alloc = memory_mmap_alloc,
+	.free = memory_mmap_free
+};
+
+struct memory_type memory_mmap_hugetlb = {
+	.name = "mmap",
 	.flags = (int) MemoryFlags::MMAP | (int) MemoryFlags::HUGEPAGE,
 	.alignment = 21, /* 2 MiB hugepage */
-	.alloc = memory_hugepage_alloc,
-	.free = memory_hugepage_free
+	.alloc = memory_mmap_alloc,
+	.free = memory_mmap_free
 };

tests/unit/memory.cpp

@@ -50,7 +50,7 @@ Theory((size_t len, size_t align, struct memory_type *mt), memory, aligned, .ini
 	cr_assert(IS_ALIGNED(ptr, align), "Memory at %p is not alligned to %#zx byte bounary", ptr, align);
 
 #ifndef __APPLE__
-	if (mt == &memory_hugepage) {
+	if (mt == &memory_mmap_hugetlb) {
 		cr_assert(IS_ALIGNED(ptr, HUGEPAGESIZE), "Memory at %p is not alligned to %#x byte bounary", ptr, HUGEPAGESIZE);
 	}
 #endif