new lockless refcount patches, disable the old ones

1 files changed, 133 insertions, 0 deletions

diff --git a/debian/patches/0003-libdiskfs-lock-less-reference-counting-for-peropen-o.patch b/debian/patches/0003-libdiskfs-lock-less-reference-counting-for-peropen-o.patch
new file mode 100644
index 00000000..04a9210c
--- /dev/null
+++ b/debian/patches/0003-libdiskfs-lock-less-reference-counting-for-peropen-o.patch
@@ -0,0 +1,133 @@
+From 124fef363dfd2326799dc884e4960a14f20b1e09 Mon Sep 17 00:00:00 2001
+From: Justus Winter <4winter@informatik.uni-hamburg.de>
+Date: Tue, 6 May 2014 18:58:10 +0200
+Subject: [PATCH 3/4] libdiskfs: lock-less reference counting for peropen
+ objects
+
+* libdiskfs/diskfs.h (struct peropen): Use refcount_t for field refcnt.
+* libdiskfs/peropen-make.c (diskfs_make_peropen): Initialize refcnt.
+* libdiskfs/peropen-rele.c (diskfs_release_peropen): Adjust accordingly.
+* libdiskfs/protid-make.c (diskfs_start_protid): Likewise.  Also, the
+node must no longer be locked, adjust comment accordingly.
+(diskfs_create_protid): Likewise.
+---
+ libdiskfs/diskfs.h       |  7 ++++---
+ libdiskfs/peropen-make.c |  2 +-
+ libdiskfs/peropen-rele.c | 11 +++--------
+ libdiskfs/protid-make.c  |  8 ++++----
+ 4 files changed, 12 insertions(+), 16 deletions(-)
+
+diff --git a/libdiskfs/diskfs.h b/libdiskfs/diskfs.h
+index 8151ddc..ae1a150 100644
+--- a/libdiskfs/diskfs.h
++++ b/libdiskfs/diskfs.h
+@@ -28,6 +28,7 @@
+ #include <hurd/iohelp.h>
+ #include <idvec.h>
+ #include <features.h>
++#include <refcount.h>
+ 
+ #ifdef DISKFS_DEFINE_EXTERN_INLINE
+ #define DISKFS_EXTERN_INLINE
+@@ -57,7 +58,7 @@ struct peropen
+ {
+   int filepointer;
+   int lock_status;
+-  int refcnt;
++  refcount_t refcnt;
+   int openstat;
+ 
+   struct node *np;
+@@ -792,12 +793,12 @@ diskfs_create_node (struct node *dir, const char *name, mode_t mode,
+ 		    struct dirstat *ds);
+ 
+ /* Create and return a protid for an existing peropen PO in CRED,
+-   referring to user USER.  The node PO->np must be locked. */
++   referring to user USER.  */
+ error_t diskfs_create_protid (struct peropen *po, struct iouser *user,
+ 			      struct protid **cred);
+ 
+ /* Build and return in CRED a protid which has no user identification, for
+-   peropen PO.  The node PO->np must be locked.  */
++   peropen PO.  */
+ error_t diskfs_start_protid (struct peropen *po, struct protid **cred);
+ 
+ /* Finish building protid CRED started with diskfs_start_protid;
+diff --git a/libdiskfs/peropen-make.c b/libdiskfs/peropen-make.c
+index eba037f..6d5ca01 100644
+--- a/libdiskfs/peropen-make.c
++++ b/libdiskfs/peropen-make.c
+@@ -31,7 +31,7 @@ diskfs_make_peropen (struct node *np, int flags, struct peropen *context,
+ 
+   po->filepointer = 0;
+   po->lock_status = LOCK_UN;
+-  po->refcnt = 0;
++  refcount_init (&po->refcnt, 0);
+   po->openstat = flags;
+   po->np = np;
+   po->path = NULL;
+diff --git a/libdiskfs/peropen-rele.c b/libdiskfs/peropen-rele.c
+index d3f7492..64cea18 100644
+--- a/libdiskfs/peropen-rele.c
++++ b/libdiskfs/peropen-rele.c
+@@ -22,13 +22,8 @@
+ void
+ diskfs_release_peropen (struct peropen *po)
+ {
+-  pthread_mutex_lock (&po->np->lock);
+-
+-  if (--po->refcnt)
+-    {
+-      pthread_mutex_unlock (&po->np->lock);
+-      return;
+-    }
++  if (refcount_deref (&po->refcnt) > 0)
++    return;
+ 
+   if (po->root_parent)
+     mach_port_deallocate (mach_task_self (), po->root_parent);
+@@ -43,7 +38,7 @@ diskfs_release_peropen (struct peropen *po)
+     fshelp_acquire_lock (&po->np->userlock, &po->lock_status,
+ 			 &po->np->lock, LOCK_UN);
+ 
+-  diskfs_nput (po->np);
++  diskfs_nrele (po->np);
+ 
+   free (po->path);
+   free (po);
+diff --git a/libdiskfs/protid-make.c b/libdiskfs/protid-make.c
+index b39b92a..22aaa2e 100644
+--- a/libdiskfs/protid-make.c
++++ b/libdiskfs/protid-make.c
+@@ -20,7 +20,7 @@
+ #include <assert.h>
+ 
+ /* Build and return in CRED a protid which has no user identification, for
+-   peropen PO.  The node PO->np must be locked.  */
++   peropen PO.  */
+ error_t
+ diskfs_start_protid (struct peropen *po, struct protid **cred)
+ {
+@@ -29,7 +29,7 @@ diskfs_start_protid (struct peropen *po, struct protid **cred)
+ 				 sizeof (struct protid), cred);
+   if (! err)
+     {
+-      po->refcnt++;
++      refcount_ref (&po->refcnt);
+       (*cred)->po = po;
+       (*cred)->shared_object = MACH_PORT_NULL;
+       (*cred)->mapped = 0;
+@@ -55,8 +55,8 @@ diskfs_finish_protid (struct protid *cred, struct iouser *user)
+   assert_perror (err);
+ }
+ 
+-/* Create and return a protid for an existing peropen PO in CRED for USER.
+-   The node PO->np must be locked. */
++/* Create and return a protid for an existing peropen PO in CRED for
++   USER.  */
+ error_t
+ diskfs_create_protid (struct peropen *po, struct iouser *user,
+ 		      struct protid **cred)
+-- 
+2.0.0.rc0
+