From ba9ef7fdee07c42bc772c8b515bc9d808c401112 Mon Sep 17 00:00:00 2001
From: Christian Helmuth <christian.helmuth@genode-labs.com>
Date: Thu, 15 Jun 2017 15:20:19 +0200
Subject: [PATCH] foc: use slab for meta-data in RPC cap factory

---
 .../src/core/include/rpc_cap_factory.h        | 22 ++++++++++++++++---
 repos/base-foc/src/core/rpc_cap_factory.cc    |  6 ++---
 repos/os/run/timer.run                        |  5 ++---
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/repos/base-foc/src/core/include/rpc_cap_factory.h b/repos/base-foc/src/core/include/rpc_cap_factory.h
index 0d45757ee4..41df0c1ce6 100644
--- a/repos/base-foc/src/core/include/rpc_cap_factory.h
+++ b/repos/base-foc/src/core/include/rpc_cap_factory.h
@@ -16,9 +16,14 @@
 
 /* Genode includes */
 #include <base/rpc_server.h>
-#include <base/allocator.h>
+#include <base/heap.h>
+#include <base/tslab.h>
 #include <base/object_pool.h>
 
+/* base-internal includes */
+#include <base/internal/page_size.h>
+
+
 namespace Genode { class Rpc_cap_factory; }
 
 class Genode::Rpc_cap_factory
@@ -31,11 +36,22 @@ class Genode::Rpc_cap_factory
 		};
 
 		Object_pool<Entry> _pool;
-		Allocator         &_md_alloc;
+
+		/*
+		 * Dimension '_entry_slab' such that slab blocks (including the
+		 * meta-data overhead of the sliced-heap blocks) are page sized.
+		 */
+		static constexpr size_t SLAB_BLOCK_SIZE =
+			get_page_size() - Sliced_heap::meta_data_size();
+
+		uint8_t _initial_sb[SLAB_BLOCK_SIZE];
+
+		Tslab<Entry, SLAB_BLOCK_SIZE> _entry_slab;
 
 	public:
 
-		Rpc_cap_factory(Allocator &md_alloc) : _md_alloc(md_alloc) { }
+		Rpc_cap_factory(Allocator &md_alloc)
+		: _entry_slab(md_alloc, _initial_sb) { }
 
 		~Rpc_cap_factory();
 
diff --git a/repos/base-foc/src/core/rpc_cap_factory.cc b/repos/base-foc/src/core/rpc_cap_factory.cc
index fefc8001fa..c18f5e6cb3 100644
--- a/repos/base-foc/src/core/rpc_cap_factory.cc
+++ b/repos/base-foc/src/core/rpc_cap_factory.cc
@@ -144,7 +144,7 @@ Native_capability Rpc_cap_factory::alloc(Native_capability ep)
 	 * so this is not an issue.
 	 */
 	if (cap.valid())
-		_pool.insert(new (_md_alloc) Entry(cap));
+		_pool.insert(new (_entry_slab) Entry(cap));
 	return cap;
 }
 
@@ -167,7 +167,7 @@ void Rpc_cap_factory::free(Native_capability cap)
 		} else
 			warning("Could not find capability to be deleted");
 	});
-	if (entry) destroy(_md_alloc, entry);
+	if (entry) destroy(_entry_slab, entry);
 }
 
 
@@ -175,7 +175,7 @@ Rpc_cap_factory::~Rpc_cap_factory()
 {
 	_pool.remove_all([this] (Entry *e) {
 		if (!e) return;
-		destroy(_md_alloc, e);
+		destroy(_entry_slab, e);
 	});
 }
 
diff --git a/repos/os/run/timer.run b/repos/os/run/timer.run
index d7018e5c4b..9d3a9bce67 100644
--- a/repos/os/run/timer.run
+++ b/repos/os/run/timer.run
@@ -26,12 +26,11 @@ install_config {
 	<default-route>
 		<any-service><parent/><any-child/></any-service>
 	</default-route>
-	<default caps="1000"/>
-	<start name="timer">
+	<start name="timer" caps="60">
 		<resource name="RAM" quantum="1M"/>
 		<provides><service name="Timer"/></provides>
 	</start>
-	<start name="client">
+	<start name="client" caps="300">
 		<binary name="test-timer"/>
 		<resource name="RAM" quantum="10M"/>
 	</start>