add patch series

4 files changed, 393 insertions, 0 deletions

diff --git a/debian/patches/0001-ipc-rework-the-kernel-message-buffer-cache.patch b/debian/patches/0001-ipc-rework-the-kernel-message-buffer-cache.patch
new file mode 100644
index 0000000..b166cf0
--- /dev/null
+++ b/debian/patches/0001-ipc-rework-the-kernel-message-buffer-cache.patch
@@ -0,0 +1,325 @@
+From e23a941eaf5aabe087f50700213c05c6d269d63b Mon Sep 17 00:00:00 2001
+From: Justus Winter <4winter@informatik.uni-hamburg.de>
+Date: Wed, 17 Dec 2014 14:21:15 +0100
+Subject: [PATCH gnumach 1/3] ipc: rework the kernel message buffer cache
+
+Keep a per-processor stack of free kernel messages buffers.
+
+* ipc/ipc_kmsg.h (IKM_CACHE_SIZE): New macro.
+(struct ipc_mksg_cpu_cache): New type.
+(ipc_kmsg_cache): Use the new type for the cache.
+(ikm_cache): Drop macro.
+(ikm_cache_get, ikm_cache_put): New functions.
+(ikm_free): Return buffers instead of freeing them.
+(_ikm_free): New version of `ikm_free' that only frees buffers.
+* ipc/ipc_kmsg.c (ipc_kmsg_cache): Use new type.
+(ipc_kmsg_get, ipc_kmsg_put): Use new functions.
+* ipc/mach_msg.c (mach_msg_trap): Likewise.
+* kern/exception.c (exception_raise): Likewise.
+(exception_parse_reply): Likewise.
+* kern/ipc_kobject.c (ipc_kobject_server): Likewise.
+---
+ ipc/ipc_kmsg.c     | 29 ++++---------------
+ ipc/ipc_kmsg.h     | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++--
+ ipc/mach_msg.c     | 14 ++++-----
+ kern/exception.c   | 28 ++++--------------
+ kern/ipc_kobject.c |  6 +---
+ 5 files changed, 97 insertions(+), 63 deletions(-)
+
+diff --git a/ipc/ipc_kmsg.c b/ipc/ipc_kmsg.c
+index 66643fd..04cdbc9 100644
+--- a/ipc/ipc_kmsg.c
++++ b/ipc/ipc_kmsg.c
+@@ -73,7 +73,7 @@
+ #define ptr_align(x)	\
+ 	( ( ((vm_offset_t)(x)) + (sizeof(vm_offset_t)-1) ) & ~(sizeof(vm_offset_t)-1) )
+ 
+-ipc_kmsg_t ipc_kmsg_cache[NCPUS];
++struct ipc_kmsg_cpu_cache ipc_kmsg_cache[NCPUS];
+ 
+ /*
+  *	Routine:	ipc_kmsg_enqueue
+@@ -506,23 +506,9 @@ ipc_kmsg_get(
+ 	if ((size < sizeof(mach_msg_header_t)) || (size & 3))
+ 		return MACH_SEND_MSG_TOO_SMALL;
+ 
+-	if (size <= IKM_SAVED_MSG_SIZE) {
+-		kmsg = ikm_cache();
+-		if (kmsg != IKM_NULL) {
+-			ikm_cache() = IKM_NULL;
+-			ikm_check_initialized(kmsg, IKM_SAVED_KMSG_SIZE);
+-		} else {
+-			kmsg = ikm_alloc(IKM_SAVED_MSG_SIZE);
+-			if (kmsg == IKM_NULL)
+-				return MACH_SEND_NO_BUFFER;
+-			ikm_init(kmsg, IKM_SAVED_MSG_SIZE);
+-		}
+-	} else {
+-		kmsg = ikm_alloc(size);
+-		if (kmsg == IKM_NULL)
+-			return MACH_SEND_NO_BUFFER;
+-		ikm_init(kmsg, size);
+-	}
++	kmsg = ikm_cache_get (size);
++	if (kmsg == IKM_NULL)
++		return MACH_SEND_NO_BUFFER;
+ 
+ 	if (copyinmsg(msg, &kmsg->ikm_header, size)) {
+ 		ikm_free(kmsg);
+@@ -599,12 +585,7 @@ ipc_kmsg_put(
+ 	else
+ 		mr = MACH_MSG_SUCCESS;
+ 
+-	if ((kmsg->ikm_size == IKM_SAVED_KMSG_SIZE) &&
+-	    (ikm_cache() == IKM_NULL))
+-		ikm_cache() = kmsg;
+-	else
+-		ikm_free(kmsg);
+-
++	ikm_cache_put (kmsg);
+ 	return mr;
+ }
+ 
+diff --git a/ipc/ipc_kmsg.h b/ipc/ipc_kmsg.h
+index 620785b..c676996 100644
+--- a/ipc/ipc_kmsg.h
++++ b/ipc/ipc_kmsg.h
+@@ -96,11 +96,36 @@ MACRO_END
+  *	The per-processor cache seems to miss less than a per-thread cache,
+  *	and it also uses less memory.  Access to the cache doesn't
+  *	require locking.
++ *
++ *	The per-processor cache is a stack containing unused kernel
++ *	message buffers.  We choose IKM_CACHE_SIZE so that the size of
++ *	the struct ipc_kmsg_cpu_cache is a multiple of a cache line,
++ *	to prevent it bouncing between per-cpu caches.
++ *
++ *	A kernel message buffer can be allocated using
++ *	`ikm_cache_get', and returned using `ikm_cache_put'.
+  */
+ 
+-extern ipc_kmsg_t	ipc_kmsg_cache[NCPUS];
++#define IKM_CACHE_SIZE	(((1 << CPU_L1_SHIFT) - sizeof (size_t))	\
++			 / sizeof (ipc_kmsg_t))
++
++struct ipc_kmsg_cpu_cache
++{
++	size_t		count;
++	ipc_kmsg_t	buffers[IKM_CACHE_SIZE];
++};
++
++extern struct ipc_kmsg_cpu_cache ipc_kmsg_cache[NCPUS];
++
++/* Return a kernel message buffer of at least SIZE size, preferably
++   from the cache.  This functions is defined below.  */
++static inline ipc_kmsg_t ikm_cache_get (mach_msg_size_t size)
++	__attribute__ ((always_inline));
+ 
+-#define ikm_cache()     ipc_kmsg_cache[cpu_number()]
++/* Return a kernel message buffer to the cache, or free it.  This
++   functions is defined below.  */
++static inline void ikm_cache_put (ipc_kmsg_t kmsg)
++	__attribute__ ((always_inline));
+ 
+ /*
+  *	The size of the kernel message buffers that will be cached.
+@@ -150,11 +175,18 @@ MACRO_BEGIN								\
+ 	register vm_size_t _size = (kmsg)->ikm_size;			\
+ 									\
+ 	if ((integer_t)_size > 0)					\
+-		kfree((vm_offset_t) (kmsg), _size);			\
++		ikm_cache_put (kmsg);					\
+ 	else								\
+ 		ipc_kmsg_free(kmsg);					\
+ MACRO_END
+ 
++#define	_ikm_free(kmsg)							\
++MACRO_BEGIN								\
++	vm_size_t _size = (kmsg)->ikm_size;				\
++	assert (_size != IKM_SIZE_NETWORK);				\
++	kfree((vm_offset_t) (kmsg), _size);				\
++MACRO_END
++
+ /*
+  *	struct ipc_kmsg_queue is defined in ipc/ipc_kmsg_queue.h
+  */
+@@ -280,5 +312,50 @@ ipc_kmsg_copyout_pseudo(ipc_kmsg_t, ipc_space_t, vm_map_t);
+ 
+ extern void
+ ipc_kmsg_copyout_dest(ipc_kmsg_t, ipc_space_t);
++
++static inline ipc_kmsg_t
++ikm_cache_get (mach_msg_size_t size)
++{
++	ipc_kmsg_t kmsg;
++	struct ipc_kmsg_cpu_cache *c = &ipc_kmsg_cache[cpu_number ()];
++
++	if (size < IKM_SAVED_MSG_SIZE)
++		size = IKM_SAVED_MSG_SIZE;
++
++	if (size > IKM_SAVED_MSG_SIZE
++	    || c->count == 0) {
++		kmsg = ikm_alloc (size);
++		if (kmsg)
++			ikm_init (kmsg, size);
++		return kmsg;
++	}
++
++	c->count -= 1;
++	kmsg = c->buffers[c->count];
++
++#if	MACH_IPC_TEST
++	ikm_check_initialized (kmsg, IKM_SAVED_KMSG_SIZE);
++#endif	/* MACH_IPC_TEST */
++	return kmsg;
++}
++
++static inline void
++ikm_cache_put (ipc_kmsg_t kmsg)
++{
++	struct ipc_kmsg_cpu_cache *c = &ipc_kmsg_cache[cpu_number ()];
++
++	if (kmsg->ikm_size != IKM_SAVED_KMSG_SIZE
++	    || c->count == IKM_CACHE_SIZE) {
++		_ikm_free (kmsg);
++		return;
++	}
++
++	c->buffers[c->count] = kmsg;
++	c->count += 1;
++
++#if	MACH_IPC_TEST
++	ikm_check_initialized (kmsg, IKM_SAVED_KMSG_SIZE);
++#endif	/* MACH_IPC_TEST */
++}
+ 
+ #endif	/* _IPC_IPC_KMSG_H_ */
+diff --git a/ipc/mach_msg.c b/ipc/mach_msg.c
+index 1e122c7..cdf16ea 100644
+--- a/ipc/mach_msg.c
++++ b/ipc/mach_msg.c
+@@ -451,16 +451,14 @@ mach_msg_trap(
+ 
+ 		if ((send_size > IKM_SAVED_MSG_SIZE) ||
+ 		    (send_size < sizeof(mach_msg_header_t)) ||
+-		    (send_size & 3) ||
+-		    ((kmsg = ikm_cache()) == IKM_NULL))
++		    (send_size & 3))
+ 			goto slow_get;
+ 
+-		ikm_cache() = IKM_NULL;
+-		ikm_check_initialized(kmsg, IKM_SAVED_KMSG_SIZE);
++		kmsg = ikm_cache_get (IKM_SAVED_MSG_SIZE);
+ 
+ 		if (copyinmsg(msg, &kmsg->ikm_header,
+ 			      send_size)) {
+-			ikm_free(kmsg);
++			ikm_cache_put (kmsg);
+ 			goto slow_get;
+ 		}
+ 
+@@ -1263,18 +1261,16 @@ mach_msg_trap(
+ 		 *	We have the reply message data in kmsg,
+ 		 *	and the reply message size in reply_size.
+ 		 *	Just need to copy it out to the user and free kmsg.
+-		 *	We must check ikm_cache after copyoutmsg.
+ 		 */
+ 
+ 		ikm_check_initialized(kmsg, kmsg->ikm_size);
+ 
+ 		if ((kmsg->ikm_size != IKM_SAVED_KMSG_SIZE) ||
+ 		    copyoutmsg(&kmsg->ikm_header, msg,
+-			       reply_size) ||
+-		    (ikm_cache() != IKM_NULL))
++			       reply_size))
+ 			goto slow_put;
+ 
+-		ikm_cache() = kmsg;
++		ikm_cache_put (kmsg);
+ 		thread_syscall_return(MACH_MSG_SUCCESS);
+ 		/*NOTREACHED*/
+ 		return MACH_MSG_SUCCESS; /* help for the compiler */
+diff --git a/kern/exception.c b/kern/exception.c
+index 7954fba..72a4f29 100644
+--- a/kern/exception.c
++++ b/kern/exception.c
+@@ -348,16 +348,9 @@ exception_raise(
+ 	 *	and it will give the buffer back with its reply.
+ 	 */
+ 
+-	kmsg = ikm_cache();
+-	if (kmsg != IKM_NULL) {
+-		ikm_cache() = IKM_NULL;
+-		ikm_check_initialized(kmsg, IKM_SAVED_KMSG_SIZE);
+-	} else {
+-		kmsg = ikm_alloc(IKM_SAVED_MSG_SIZE);
+-		if (kmsg == IKM_NULL)
+-			panic("exception_raise");
+-		ikm_init(kmsg, IKM_SAVED_MSG_SIZE);
+-	}
++	kmsg = ikm_cache_get (IKM_SAVED_MSG_SIZE);
++	if (kmsg == IKM_NULL)
++		panic("exception_raise");
+ 
+ 	/*
+ 	 *	We need a reply port for the RPC.
+@@ -681,22 +674,19 @@ exception_raise(
+ 
+ 	/*
+ 	 *	Optimized version of ipc_kmsg_put.
+-	 *	We must check ikm_cache after copyoutmsg.
+ 	 */
+-
+ 	ikm_check_initialized(kmsg, kmsg->ikm_size);
+ 	assert(kmsg->ikm_size == IKM_SAVED_KMSG_SIZE);
+ 
+ 	if (copyoutmsg(&kmsg->ikm_header, receiver->ith_msg,
+-		       sizeof(struct mach_exception)) ||
+-	    (ikm_cache() != IKM_NULL)) {
++		       sizeof(struct mach_exception))) {
+ 		mr = ipc_kmsg_put(receiver->ith_msg, kmsg,
+ 				  kmsg->ikm_header.msgh_size);
+ 		thread_syscall_return(mr);
+ 		/*NOTREACHED*/
+ 	}
+ 
+-	ikm_cache() = kmsg;
++	ikm_cache_put (kmsg);
+ 	thread_syscall_return(MACH_MSG_SUCCESS);
+ 	/*NOTREACHED*/
+ #ifndef	__GNUC__
+@@ -809,13 +799,7 @@ exception_parse_reply(ipc_kmsg_t kmsg)
+ 	}
+ 
+ 	kr = msg->RetCode;
+-
+-	if ((kmsg->ikm_size == IKM_SAVED_KMSG_SIZE) &&
+-	    (ikm_cache() == IKM_NULL))
+-		ikm_cache() = kmsg;
+-	else
+-		ikm_free(kmsg);
+-
++	ikm_cache_put (kmsg);
+ 	return kr;
+ }
+ 
+diff --git a/kern/ipc_kobject.c b/kern/ipc_kobject.c
+index bf22028..27535b0 100644
+--- a/kern/ipc_kobject.c
++++ b/kern/ipc_kobject.c
+@@ -236,11 +236,7 @@ ipc_kobject_server(request)
+ 		/* like ipc_kmsg_put, but without the copyout */
+ 
+ 		ikm_check_initialized(request, request->ikm_size);
+-		if ((request->ikm_size == IKM_SAVED_KMSG_SIZE) &&
+-		    (ikm_cache() == IKM_NULL))
+-			ikm_cache() = request;
+-		else
+-			ikm_free(request);
++		ikm_cache_put (request);
+ 	} else {
+ 		/*
+ 		 *	The message contents of the request are intact.
+-- 
+2.1.3
+
diff --git a/debian/patches/0002-ipc-also-use-the-kernel-message-buffer-cache-for-ker.patch b/debian/patches/0002-ipc-also-use-the-kernel-message-buffer-cache-for-ker.patch
new file mode 100644
index 0000000..aa64b34
--- /dev/null
+++ b/debian/patches/0002-ipc-also-use-the-kernel-message-buffer-cache-for-ker.patch
@@ -0,0 +1,40 @@
+From b4bfcd3564cd7443a44aa8f238c3c865a18a10f5 Mon Sep 17 00:00:00 2001
+From: Justus Winter <4winter@informatik.uni-hamburg.de>
+Date: Wed, 17 Dec 2014 14:47:19 +0100
+Subject: [PATCH gnumach 2/3] ipc: also use the kernel message buffer cache for
+ kernel messages
+
+* ipc/ipc_kmsg.c (ipc_kmsg_get_from_kernel): Use the ikm cache.
+(ipc_kmsg_put_to_kernel): Likewis.
+---
+ ipc/ipc_kmsg.c | 5 ++---
+ 1 file changed, 2 insertions(+), 3 deletions(-)
+
+diff --git a/ipc/ipc_kmsg.c b/ipc/ipc_kmsg.c
+index 04cdbc9..c26569b 100644
+--- a/ipc/ipc_kmsg.c
++++ b/ipc/ipc_kmsg.c
+@@ -544,10 +544,9 @@ ipc_kmsg_get_from_kernel(
+ 	assert(size >= sizeof(mach_msg_header_t));
+ 	assert((size & 3) == 0);
+ 
+-	kmsg = ikm_alloc(size);
++	kmsg = ikm_cache_get (size);
+ 	if (kmsg == IKM_NULL)
+ 		return MACH_SEND_NO_BUFFER;
+-	ikm_init(kmsg, size);
+ 
+ 	memcpy(&kmsg->ikm_header, msg, size);
+ 
+@@ -611,7 +610,7 @@ ipc_kmsg_put_to_kernel(
+ 
+ 	memcpy(msg, &kmsg->ikm_header, size);
+ 
+-	ikm_free(kmsg);
++	ikm_cache_put (kmsg);
+ }
+ 
+ /*
+-- 
+2.1.3
+
diff --git a/debian/patches/0003-doublesize-me.patch b/debian/patches/0003-doublesize-me.patch
new file mode 100644
index 0000000..9e2c569
--- /dev/null
+++ b/debian/patches/0003-doublesize-me.patch
@@ -0,0 +1,25 @@
+From bcf91ed9f1877a8b1eaacf2bcb1e74c29e4110a3 Mon Sep 17 00:00:00 2001
+From: Justus Winter <4winter@informatik.uni-hamburg.de>
+Date: Wed, 17 Dec 2014 16:50:29 +0100
+Subject: [PATCH gnumach 3/3] doublesize me
+
+---
+ ipc/ipc_kmsg.h | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/ipc/ipc_kmsg.h b/ipc/ipc_kmsg.h
+index c676996..a2ac8ba 100644
+--- a/ipc/ipc_kmsg.h
++++ b/ipc/ipc_kmsg.h
+@@ -106,7 +106,7 @@ MACRO_END
+  *	`ikm_cache_get', and returned using `ikm_cache_put'.
+  */
+ 
+-#define IKM_CACHE_SIZE	(((1 << CPU_L1_SHIFT) - sizeof (size_t))	\
++#define IKM_CACHE_SIZE	((4 * (1 << CPU_L1_SHIFT) - sizeof (size_t))	\
+ 			 / sizeof (ipc_kmsg_t))
+ 
+ struct ipc_kmsg_cpu_cache
+-- 
+2.1.3
+
diff --git a/debian/patches/series b/debian/patches/series
index 52021c2..e318856 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -6,3 +6,6 @@
 
 Add-some-padding-to-make-objects-fit-a-single-cache-.patch
 vm_cache_policy.patch
+0001-ipc-rework-the-kernel-message-buffer-cache.patch
+0002-ipc-also-use-the-kernel-message-buffer-cache-for-ker.patch
+0003-doublesize-me.patch