X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=module%2Fzfs%2Fzfs_rlock.c;h=136972b32d03dc7bb9554939b641234efb26e040;hb=refs%2Fheads%2Frertzinger%2Ffeature-zpool-get--p;hp=26ad58de8b83a1d6176bf2af07aec002ec0f9bca;hpb=8926ab7a50d60d855e4d49d2ed7bdef49dd56149;p=zfs.git

diff --git a/module/zfs/zfs_rlock.c b/module/zfs/zfs_rlock.c
index 26ad58d..136972b 100644
--- a/module/zfs/zfs_rlock.c
+++ b/module/zfs/zfs_rlock.c
@@ -22,6 +22,9 @@
  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
 
 /*
  * This file contains the code to implement file range locking in
@@ -199,7 +202,7 @@ zfs_range_proxify(avl_tree_t *tree, rl_t *rl)
 	rl->r_cnt = 0;
 
 	/* create a proxy range lock */
-	proxy = kmem_alloc(sizeof (rl_t), KM_SLEEP);
+	proxy = kmem_alloc(sizeof (rl_t), KM_PUSHPAGE);
 	proxy->r_off = rl->r_off;
 	proxy->r_len = rl->r_len;
 	proxy->r_cnt = 1;
@@ -228,7 +231,7 @@ zfs_range_split(avl_tree_t *tree, rl_t *rl, uint64_t off)
 	ASSERT(rl->r_read_wanted == B_FALSE);
 
 	/* create the rear proxy range lock */
-	rear = kmem_alloc(sizeof (rl_t), KM_SLEEP);
+	rear = kmem_alloc(sizeof (rl_t), KM_PUSHPAGE);
 	rear->r_off = off;
 	rear->r_len = rl->r_off + rl->r_len - off;
 	rear->r_cnt = rl->r_cnt;
@@ -253,7 +256,7 @@ zfs_range_new_proxy(avl_tree_t *tree, uint64_t off, uint64_t len)
 	rl_t *rl;
 
 	ASSERT(len);
-	rl = kmem_alloc(sizeof (rl_t), KM_SLEEP);
+	rl = kmem_alloc(sizeof (rl_t), KM_PUSHPAGE);
 	rl->r_off = off;
 	rl->r_len = len;
 	rl->r_cnt = 1;
@@ -426,7 +429,7 @@ zfs_range_lock(znode_t *zp, uint64_t off, uint64_t len, rl_type_t type)
 
 	ASSERT(type == RL_READER || type == RL_WRITER || type == RL_APPEND);
 
-	new = kmem_alloc(sizeof (rl_t), KM_SLEEP);
+	new = kmem_alloc(sizeof (rl_t), KM_PUSHPAGE);
 	new->r_zp = zp;
 	new->r_off = off;
 	if (len + off < off)	/* overflow */
@@ -471,7 +474,7 @@ zfs_range_free(void *arg)
  * Unlock a reader lock
  */
 static void
-zfs_range_unlock_reader(znode_t *zp, rl_t *remove)
+zfs_range_unlock_reader(znode_t *zp, rl_t *remove, list_t *free_list)
 {
 	avl_tree_t *tree = &zp->z_range_avl;
 	rl_t *rl, *next = NULL;
@@ -486,18 +489,18 @@ zfs_range_unlock_reader(znode_t *zp, rl_t *remove)
 	 */
 	if (remove->r_cnt == 1) {
 		avl_remove(tree, remove);
-		mutex_exit(&zp->z_range_lock);
+
 		if (remove->r_write_wanted)
 			cv_broadcast(&remove->r_wr_cv);
 
 		if (remove->r_read_wanted)
 			cv_broadcast(&remove->r_rd_cv);
 
-		taskq_dispatch(system_taskq, zfs_range_free, remove, 0);
+		list_insert_tail(free_list, remove);
 	} else {
-		ASSERT3U(remove->r_cnt, ==, 0);
-		ASSERT3U(remove->r_write_wanted, ==, 0);
-		ASSERT3U(remove->r_read_wanted, ==, 0);
+		ASSERT0(remove->r_cnt);
+		ASSERT0(remove->r_write_wanted);
+		ASSERT0(remove->r_read_wanted);
 		/*
 		 * Find start proxy representing this reader lock,
 		 * then decrement ref count on all proxies
@@ -526,12 +529,10 @@ zfs_range_unlock_reader(znode_t *zp, rl_t *remove)
 				if (rl->r_read_wanted)
 					cv_broadcast(&rl->r_rd_cv);
 
-				taskq_dispatch(system_taskq,
-				    zfs_range_free, rl, 0);
+				list_insert_tail(free_list, rl);
 			}
 		}
 
-		mutex_exit(&zp->z_range_lock);
 		kmem_free(remove, sizeof (rl_t));
 	}
 }
@@ -543,30 +544,40 @@ void
 zfs_range_unlock(rl_t *rl)
 {
 	znode_t *zp = rl->r_zp;
+	list_t free_list;
+	rl_t *free_rl;
 
 	ASSERT(rl->r_type == RL_WRITER || rl->r_type == RL_READER);
 	ASSERT(rl->r_cnt == 1 || rl->r_cnt == 0);
 	ASSERT(!rl->r_proxy);
+	list_create(&free_list, sizeof(rl_t), offsetof(rl_t, rl_node));
 
 	mutex_enter(&zp->z_range_lock);
 	if (rl->r_type == RL_WRITER) {
 		/* writer locks can't be shared or split */
 		avl_remove(&zp->z_range_avl, rl);
-		mutex_exit(&zp->z_range_lock);
 		if (rl->r_write_wanted)
 			cv_broadcast(&rl->r_wr_cv);
 
 		if (rl->r_read_wanted)
 			cv_broadcast(&rl->r_rd_cv);
 
-		taskq_dispatch(system_taskq, zfs_range_free, rl, 0);
+		list_insert_tail(&free_list, rl);
 	} else {
 		/*
 		 * lock may be shared, let zfs_range_unlock_reader()
 		 * release the zp->z_range_lock lock and free the rl_t
 		 */
-		zfs_range_unlock_reader(zp, rl);
+		zfs_range_unlock_reader(zp, rl, &free_list);
+	}
+	mutex_exit(&zp->z_range_lock);
+
+	while ((free_rl = list_head(&free_list)) != NULL) {
+		list_remove(&free_list, free_rl);
+		zfs_range_free(free_rl);
 	}
+
+	list_destroy(&free_list);
 }
 
 /*
@@ -590,11 +601,13 @@ zfs_range_reduce(rl_t *rl, uint64_t off, uint64_t len)
 	mutex_enter(&zp->z_range_lock);
 	rl->r_off = off;
 	rl->r_len = len;
-	mutex_exit(&zp->z_range_lock);
+
 	if (rl->r_write_wanted)
 		cv_broadcast(&rl->r_wr_cv);
 	if (rl->r_read_wanted)
 		cv_broadcast(&rl->r_rd_cv);
+
+	mutex_exit(&zp->z_range_lock);
 }
 
 /*