[PATCH 00/39] drop null test before destroy functions

[PATCH 00/39] drop null test before destroy functions

[Julia Lawall]

Recent commits to kernel/git/torvalds/linux.git have made the following
functions able to tolerate NULL arguments:

kmem_cache_destroy (commit 3942d29918522)
mempool_destroy (commit 4e3ca3e033d1)
dma_pool_destroy (commit 44d7175da6ea)

These patches remove the associated NULL tests for the files that I found
easy to compile test.  If these changes are OK, I will address the
remainder later.

---

 arch/x86/kvm/mmu.c                                 |    6 --
 block/bio-integrity.c                              |    7 --
 block/bio.c                                        |    7 --
 block/blk-core.c                                   |    3 -
 block/elevator.c                                   |    3 -
 drivers/atm/he.c                                   |    7 --
 drivers/block/aoe/aoedev.c                         |    3 -
 drivers/block/drbd/drbd_main.c                     |   21 ++-----
 drivers/block/pktcdvd.c                            |    3 -
 drivers/block/rbd.c                                |    6 --
 drivers/dma/dmaengine.c                            |    6 --
 drivers/firmware/google/gsmi.c                     |    3 -
 drivers/gpu/drm/i915/i915_dma.c                    |   19 ++----
 drivers/iommu/amd_iommu_init.c                     |    7 --
 drivers/md/bcache/bset.c                           |    3 -
 drivers/md/bcache/request.c                        |    3 -
 drivers/md/bcache/super.c                          |    9 +--
 drivers/md/dm-bufio.c                              |    3 -
 drivers/md/dm-cache-target.c                       |    3 -
 drivers/md/dm-crypt.c                              |    6 --
 drivers/md/dm-io.c                                 |    3 -
 drivers/md/dm-log-userspace-base.c                 |    3 -
 drivers/md/dm-region-hash.c                        |    4 -
 drivers/md/dm.c                                    |   13 +---
 drivers/md/multipath.c                             |    3 -
 drivers/md/raid1.c                                 |    6 --
 drivers/md/raid10.c                                |    9 +--
 drivers/md/raid5.c                                 |    3 -
 drivers/mtd/nand/nandsim.c                         |    3 -
 drivers/mtd/ubi/attach.c                           |    4 -
 drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c      |    3 -
 drivers/staging/lustre/lustre/llite/super25.c      |   16 +----
 drivers/staging/lustre/lustre/obdclass/genops.c    |   24 ++------
 drivers/staging/lustre/lustre/obdclass/lu_object.c |    6 --
 drivers/staging/rdma/hfi1/user_sdma.c              |    3 -
 drivers/thunderbolt/ctl.c                          |    3 -
 drivers/usb/gadget/udc/bdc/bdc_core.c              |    3 -
 drivers/usb/gadget/udc/gr_udc.c                    |    3 -
 drivers/usb/gadget/udc/mv_u3d_core.c               |    3 -
 drivers/usb/gadget/udc/mv_udc_core.c               |    3 -
 drivers/usb/host/fotg210-hcd.c                     |   12 +---
 drivers/usb/host/fusbh200-hcd.c                    |   12 +---
 drivers/usb/host/whci/init.c                       |    3 -
 drivers/usb/host/xhci-mem.c                        |   12 +---
 fs/btrfs/backref.c                                 |    3 -
 fs/btrfs/delayed-inode.c                           |    3 -
 fs/btrfs/delayed-ref.c                             |   12 +---
 fs/btrfs/disk-io.c                                 |    3 -
 fs/btrfs/extent_io.c                               |    6 --
 fs/btrfs/extent_map.c                              |    3 -
 fs/btrfs/file.c                                    |    3 -
 fs/btrfs/inode.c                                   |   18 ++----
 fs/btrfs/ordered-data.c                            |    3 -
 fs/dlm/memory.c                                    |    6 --
 fs/ecryptfs/main.c                                 |    3 -
 fs/ext4/crypto.c                                   |    9 +--
 fs/ext4/extents_status.c                           |    3 -
 fs/ext4/mballoc.c                                  |    3 -
 fs/f2fs/crypto.c                                   |    9 +--
 fs/gfs2/main.c                                     |   29 ++--------
 fs/jbd2/journal.c                                  |   15 +----
 fs/jbd2/revoke.c                                   |   12 +---
 fs/jbd2/transaction.c                              |    6 --
 fs/jffs2/malloc.c                                  |   27 +++------
 fs/nfsd/nfscache.c                                 |    6 --
 fs/nilfs2/super.c                                  |   12 +---
 fs/ocfs2/dlm/dlmlock.c                             |    3 -
 fs/ocfs2/dlm/dlmmaster.c                           |   16 +----
 fs/ocfs2/super.c                                   |   18 ++----
 fs/ocfs2/uptodate.c                                |    3 -
 lib/debugobjects.c                                 |    3 -
 net/core/sock.c                                    |   12 +---
 net/dccp/ackvec.c                                  |   12 +---
 net/dccp/ccid.c                                    |    3 -
 net/sunrpc/sched.c                                 |   12 +---
 75 files changed, 180 insertions(+), 381 deletions(-)

[PATCH 01/39] mtd: nandsim: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/mtd/nand/nandsim.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c
index 95d0cc4..b16d70a 100644
--- a/drivers/mtd/nand/nandsim.c
+++ b/drivers/mtd/nand/nandsim.c
@@ -649,8 +649,7 @@ static void free_device(struct nandsim *ns)
 				kmem_cache_free(ns->nand_pages_slab,
 						ns->pages[i].byte);
 		}
-		if (ns->nand_pages_slab)
-			kmem_cache_destroy(ns->nand_pages_slab);
+		kmem_cache_destroy(ns->nand_pages_slab);
 		vfree(ns->pages);
 	}
 }

Re: [PATCH 01/39] mtd: nandsim: drop null test before destroy functions

[Brian Norris]

On Sun, Sep 13, 2015 at 02:14:54PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied patches 1 and 36 to l2-mtd.git

[PATCH 02/39] nilfs2: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/nilfs2/super.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index f47585b..c69455a 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1405,14 +1405,10 @@ static void nilfs_destroy_cachep(void)
 	 */
 	rcu_barrier();
 
-	if (nilfs_inode_cachep)
-		kmem_cache_destroy(nilfs_inode_cachep);
-	if (nilfs_transaction_cachep)
-		kmem_cache_destroy(nilfs_transaction_cachep);
-	if (nilfs_segbuf_cachep)
-		kmem_cache_destroy(nilfs_segbuf_cachep);
-	if (nilfs_btree_path_cache)
-		kmem_cache_destroy(nilfs_btree_path_cache);
+	kmem_cache_destroy(nilfs_inode_cachep);
+	kmem_cache_destroy(nilfs_transaction_cachep);
+	kmem_cache_destroy(nilfs_segbuf_cachep);
+	kmem_cache_destroy(nilfs_btree_path_cache);
 }
 
 static int __init nilfs_init_cachep(void)

Re: [PATCH 02/39] nilfs2: drop null test before destroy functions

[Ryusuke Konishi]

On Sun, 13 Sep 2015 14:14:55 +0200, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Looks OK.  I'll queue this in my tree.

Thanks,
Ryusuke Konishi

> 
> ---
>  fs/nilfs2/super.c |   12 ++++--------
>  1 file changed, 4 insertions(+), 8 deletions(-)
> 
> diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
> index f47585b..c69455a 100644
> --- a/fs/nilfs2/super.c
> +++ b/fs/nilfs2/super.c
> @@ -1405,14 +1405,10 @@ static void nilfs_destroy_cachep(void)
>  	 */
>  	rcu_barrier();
>  
> -	if (nilfs_inode_cachep)
> -		kmem_cache_destroy(nilfs_inode_cachep);
> -	if (nilfs_transaction_cachep)
> -		kmem_cache_destroy(nilfs_transaction_cachep);
> -	if (nilfs_segbuf_cachep)
> -		kmem_cache_destroy(nilfs_segbuf_cachep);
> -	if (nilfs_btree_path_cache)
> -		kmem_cache_destroy(nilfs_btree_path_cache);
> +	kmem_cache_destroy(nilfs_inode_cachep);
> +	kmem_cache_destroy(nilfs_transaction_cachep);
> +	kmem_cache_destroy(nilfs_segbuf_cachep);
> +	kmem_cache_destroy(nilfs_btree_path_cache);
>  }
>  
>  static int __init nilfs_init_cachep(void)
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 03/39] firmware: google: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/firmware/google/gsmi.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c
index f1ab05e..c463871 100644
--- a/drivers/firmware/google/gsmi.c
+++ b/drivers/firmware/google/gsmi.c
@@ -910,8 +910,7 @@ out_err:
 	gsmi_buf_free(gsmi_dev.param_buf);
 	gsmi_buf_free(gsmi_dev.data_buf);
 	gsmi_buf_free(gsmi_dev.name_buf);
-	if (gsmi_dev.dma_pool)
-		dma_pool_destroy(gsmi_dev.dma_pool);
+	dma_pool_destroy(gsmi_dev.dma_pool);
 	platform_device_unregister(gsmi_dev.pdev);
 	pr_info("gsmi: failed to load: %d\n", ret);
 	return ret;

[PATCH 04/39] debugobjects: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 lib/debugobjects.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 547f7f9..7bf529f 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -1089,8 +1089,7 @@ void __init debug_objects_mem_init(void)
 
 	if (!obj_cache || debug_objects_replace_static_objects()) {
 		debug_objects_enabled = 0;
-		if (obj_cache)
-			kmem_cache_destroy(obj_cache);
+		kmem_cache_destroy(obj_cache);
 		pr_warn("out of memory.\n");
 	} else
 		debug_objects_selftest();

[PATCH 05/39] xhci: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/usb/host/xhci-mem.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 9a8c936..40618d1 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1829,24 +1829,20 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
 	for (i = 1; i < MAX_HC_SLOTS; ++i)
 		xhci_free_virt_device(xhci, i);
 
-	if (xhci->segment_pool)
-		dma_pool_destroy(xhci->segment_pool);
+	dma_pool_destroy(xhci->segment_pool);
 	xhci->segment_pool = NULL;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Freed segment pool");
 
-	if (xhci->device_pool)
-		dma_pool_destroy(xhci->device_pool);
+	dma_pool_destroy(xhci->device_pool);
 	xhci->device_pool = NULL;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Freed device context pool");
 
-	if (xhci->small_streams_pool)
-		dma_pool_destroy(xhci->small_streams_pool);
+	dma_pool_destroy(xhci->small_streams_pool);
 	xhci->small_streams_pool = NULL;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"Freed small stream array pool");
 
-	if (xhci->medium_streams_pool)
-		dma_pool_destroy(xhci->medium_streams_pool);
+	dma_pool_destroy(xhci->medium_streams_pool);
 	xhci->medium_streams_pool = NULL;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"Freed medium stream array pool");

[PATCH 06/39] Btrfs: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/btrfs/backref.c       |    3 +--
 fs/btrfs/delayed-inode.c |    3 +--
 fs/btrfs/delayed-ref.c   |   12 ++++--------
 fs/btrfs/disk-io.c       |    3 +--
 fs/btrfs/extent_io.c     |    6 ++----
 fs/btrfs/extent_map.c    |    3 +--
 fs/btrfs/file.c          |    3 +--
 fs/btrfs/inode.c         |   18 ++++++------------
 fs/btrfs/ordered-data.c  |    3 +--
 9 files changed, 18 insertions(+), 36 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 6a98bdd..6416c11 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -20,8 +20,7 @@ int __init extent_map_init(void)
 
 void extent_map_exit(void)
 {
-	if (extent_map_cache)
-		kmem_cache_destroy(extent_map_cache);
+	kmem_cache_destroy(extent_map_cache);
 }
 
 /**
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index ac3e81d..54ae98d 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -787,14 +787,10 @@ btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr)
 
 void btrfs_delayed_ref_exit(void)
 {
-	if (btrfs_delayed_ref_head_cachep)
-		kmem_cache_destroy(btrfs_delayed_ref_head_cachep);
-	if (btrfs_delayed_tree_ref_cachep)
-		kmem_cache_destroy(btrfs_delayed_tree_ref_cachep);
-	if (btrfs_delayed_data_ref_cachep)
-		kmem_cache_destroy(btrfs_delayed_data_ref_cachep);
-	if (btrfs_delayed_extent_op_cachep)
-		kmem_cache_destroy(btrfs_delayed_extent_op_cachep);
+	kmem_cache_destroy(btrfs_delayed_ref_head_cachep);
+	kmem_cache_destroy(btrfs_delayed_tree_ref_cachep);
+	kmem_cache_destroy(btrfs_delayed_data_ref_cachep);
+	kmem_cache_destroy(btrfs_delayed_extent_op_cachep);
 }
 
 int btrfs_delayed_ref_init(void)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 0d98aee..6cc044d 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -103,8 +103,7 @@ int __init btrfs_end_io_wq_init(void)
 
 void btrfs_end_io_wq_exit(void)
 {
-	if (btrfs_end_io_wq_cache)
-		kmem_cache_destroy(btrfs_end_io_wq_cache);
+	kmem_cache_destroy(btrfs_end_io_wq_cache);
 }
 
 /*
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index a2ae427..1fb6ce3 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -43,8 +43,7 @@ int __init btrfs_delayed_inode_init(void)
 
 void btrfs_delayed_inode_exit(void)
 {
-	if (delayed_node_cache)
-		kmem_cache_destroy(delayed_node_cache);
+	kmem_cache_destroy(delayed_node_cache);
 }
 
 static inline void btrfs_init_delayed_node(
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index b823fac..c8d0210 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2820,8 +2820,7 @@ const struct file_operations btrfs_file_operations = {
 
 void btrfs_auto_defrag_exit(void)
 {
-	if (btrfs_inode_defrag_cachep)
-		kmem_cache_destroy(btrfs_inode_defrag_cachep);
+	kmem_cache_destroy(btrfs_inode_defrag_cachep);
 }
 
 int btrfs_auto_defrag_init(void)
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 52170cf..2e5a1e1 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -1072,6 +1072,5 @@ int __init ordered_data_init(void)
 
 void ordered_data_exit(void)
 {
-	if (btrfs_ordered_extent_cache)
-		kmem_cache_destroy(btrfs_ordered_extent_cache);
+	kmem_cache_destroy(btrfs_ordered_extent_cache);
 }
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a0fa725..c7904d3 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -9031,18 +9031,12 @@ void btrfs_destroy_cachep(void)
 	 * destroy cache.
 	 */
 	rcu_barrier();
-	if (btrfs_inode_cachep)
-		kmem_cache_destroy(btrfs_inode_cachep);
-	if (btrfs_trans_handle_cachep)
-		kmem_cache_destroy(btrfs_trans_handle_cachep);
-	if (btrfs_transaction_cachep)
-		kmem_cache_destroy(btrfs_transaction_cachep);
-	if (btrfs_path_cachep)
-		kmem_cache_destroy(btrfs_path_cachep);
-	if (btrfs_free_space_cachep)
-		kmem_cache_destroy(btrfs_free_space_cachep);
-	if (btrfs_delalloc_work_cachep)
-		kmem_cache_destroy(btrfs_delalloc_work_cachep);
+	kmem_cache_destroy(btrfs_inode_cachep);
+	kmem_cache_destroy(btrfs_trans_handle_cachep);
+	kmem_cache_destroy(btrfs_transaction_cachep);
+	kmem_cache_destroy(btrfs_path_cachep);
+	kmem_cache_destroy(btrfs_free_space_cachep);
+	kmem_cache_destroy(btrfs_delalloc_work_cachep);
 }
 
 int btrfs_init_cachep(void)
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index ecbc63d..6763b1f 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -148,8 +148,7 @@ int __init btrfs_prelim_ref_init(void)
 
 void btrfs_prelim_ref_exit(void)
 {
-	if (btrfs_prelim_ref_cache)
-		kmem_cache_destroy(btrfs_prelim_ref_cache);
+	kmem_cache_destroy(btrfs_prelim_ref_cache);
 }
 
 /*
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index f1018cf..b538b3e 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -187,10 +187,8 @@ void extent_io_exit(void)
 	 * destroy caches.
 	 */
 	rcu_barrier();
-	if (extent_state_cache)
-		kmem_cache_destroy(extent_state_cache);
-	if (extent_buffer_cache)
-		kmem_cache_destroy(extent_buffer_cache);
+	kmem_cache_destroy(extent_state_cache);
+	kmem_cache_destroy(extent_buffer_cache);
 	if (btrfs_bioset)
 		bioset_free(btrfs_bioset);
 }

Re: [PATCH 06/39] Btrfs: drop null test before destroy functions

[David Sterba]

On Sun, Sep 13, 2015 at 02:14:59PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Acked-by: David Sterba <dsterba@suse.com>

[PATCH 07/39] fs: ext4: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/ext4/crypto.c         |    9 +++------
 fs/ext4/extents_status.c |    3 +--
 fs/ext4/mballoc.c        |    3 +--
 3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 26724ae..42096d3 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -161,8 +161,7 @@ int __init ext4_init_es(void)
 
 void ext4_exit_es(void)
 {
-	if (ext4_es_cachep)
-		kmem_cache_destroy(ext4_es_cachep);
+	kmem_cache_destroy(ext4_es_cachep);
 }
 
 void ext4_es_init_tree(struct ext4_es_tree *tree)
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 34b610e..b5adfb9 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2520,8 +2520,7 @@ static void ext4_groupinfo_destroy_slabs(void)
 	int i;
 
 	for (i = 0; i < NR_GRPINFO_CACHES; i++) {
-		if (ext4_groupinfo_caches[i])
-			kmem_cache_destroy(ext4_groupinfo_caches[i]);
+		kmem_cache_destroy(ext4_groupinfo_caches[i]);
 		ext4_groupinfo_caches[i] = NULL;
 	}
 }
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index 4573155..e4d6d30 100644
--- a/fs/ext4/crypto.c
+++ b/fs/ext4/crypto.c
@@ -153,17 +153,14 @@ void ext4_exit_crypto(void)
 	list_for_each_entry_safe(pos, n, &ext4_free_crypto_ctxs, free_list)
 		kmem_cache_free(ext4_crypto_ctx_cachep, pos);
 	INIT_LIST_HEAD(&ext4_free_crypto_ctxs);
-	if (ext4_bounce_page_pool)
-		mempool_destroy(ext4_bounce_page_pool);
+	mempool_destroy(ext4_bounce_page_pool);
 	ext4_bounce_page_pool = NULL;
 	if (ext4_read_workqueue)
 		destroy_workqueue(ext4_read_workqueue);
 	ext4_read_workqueue = NULL;
-	if (ext4_crypto_ctx_cachep)
-		kmem_cache_destroy(ext4_crypto_ctx_cachep);
+	kmem_cache_destroy(ext4_crypto_ctx_cachep);
 	ext4_crypto_ctx_cachep = NULL;
-	if (ext4_crypt_info_cachep)
-		kmem_cache_destroy(ext4_crypt_info_cachep);
+	kmem_cache_destroy(ext4_crypt_info_cachep);
 	ext4_crypt_info_cachep = NULL;
 }
 

[PATCH 08/39] pktcdvd: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/block/pktcdvd.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 7be2375..cd813f9 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2803,8 +2803,7 @@ out_new_dev:
 out_mem2:
 	put_disk(disk);
 out_mem:
-	if (pd->rb_pool)
-		mempool_destroy(pd->rb_pool);
+	mempool_destroy(pd->rb_pool);
 	kfree(pd);
 out_mutex:
 	mutex_unlock(&ctl_mutex);

Re: [PATCH 08/39] pktcdvd: drop null test before destroy functions

[Jiri Kosina]

On Sun, 13 Sep 2015, Julia Lawall wrote:

> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied, thanks.

-- 
Jiri Kosina
SUSE Labs

[PATCH 09/39] aoe: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/block/aoe/aoedev.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index ffd1947..efc8a8a 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -285,8 +285,7 @@ freedev(struct aoedev *d)
 	e = t + d->ntargets;
 	for (; t < e && *t; t++)
 		freetgt(d, *t);
-	if (d->bufpool)
-		mempool_destroy(d->bufpool);
+	mempool_destroy(d->bufpool);
 	skbpoolfree(d);
 	minor_free(d->sysminor);
 

Re: [PATCH 09/39] aoe: drop null test before destroy functions

[Ed Cashin]

ACK.  Thanks.

On 09/13/2015 08:15 AM, Julia Lawall wrote:
> Remove unneeded NULL test.
>
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>    \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>
> ---
>   drivers/block/aoe/aoedev.c |    3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
> index ffd1947..efc8a8a 100644
> --- a/drivers/block/aoe/aoedev.c
> +++ b/drivers/block/aoe/aoedev.c
> @@ -285,8 +285,7 @@ freedev(struct aoedev *d)
>   	e = t + d->ntargets;
>   	for (; t < e && *t; t++)
>   		freetgt(d, *t);
> -	if (d->bufpool)
> -		mempool_destroy(d->bufpool);
> +	mempool_destroy(d->bufpool);
>   	skbpoolfree(d);
>   	minor_free(d->sysminor);
>   
>

[PATCH 10/39] atm: he: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/atm/he.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/atm/he.c b/drivers/atm/he.c
index a8da3a5..0f5cb37 100644
--- a/drivers/atm/he.c
+++ b/drivers/atm/he.c
@@ -1578,9 +1578,7 @@ he_stop(struct he_dev *he_dev)
 
 	kfree(he_dev->rbpl_virt);
 	kfree(he_dev->rbpl_table);
-
-	if (he_dev->rbpl_pool)
-		dma_pool_destroy(he_dev->rbpl_pool);
+	dma_pool_destroy(he_dev->rbpl_pool);
 
 	if (he_dev->rbrq_base)
 		dma_free_coherent(&he_dev->pci_dev->dev, CONFIG_RBRQ_SIZE * sizeof(struct he_rbrq),
@@ -1594,8 +1592,7 @@ he_stop(struct he_dev *he_dev)
 		dma_free_coherent(&he_dev->pci_dev->dev, CONFIG_TBRQ_SIZE * sizeof(struct he_tbrq),
 				  he_dev->tpdrq_base, he_dev->tpdrq_phys);
 
-	if (he_dev->tpd_pool)
-		dma_pool_destroy(he_dev->tpd_pool);
+	dma_pool_destroy(he_dev->tpd_pool);
 
 	if (he_dev->pci_dev) {
 		pci_read_config_word(he_dev->pci_dev, PCI_COMMAND, &command);

Re: [PATCH 10/39] atm: he: drop null test before destroy functions

[David Miller]

From: Julia Lawall <Julia.Lawall@lip6.fr>
Date: Sun, 13 Sep 2015 14:15:03 +0200

> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied.

[PATCH 11/39] hfi1: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/staging/rdma/hfi1/user_sdma.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/staging/rdma/hfi1/user_sdma.c b/drivers/staging/rdma/hfi1/user_sdma.c
index 5552661..6620262 100644
--- a/drivers/staging/rdma/hfi1/user_sdma.c
+++ b/drivers/staging/rdma/hfi1/user_sdma.c
@@ -486,8 +486,7 @@ int hfi1_user_sdma_free_queues(struct hfi1_filedata *fd)
 			}
 			kfree(pq->reqs);
 		}
-		if (pq->txreq_cache)
-			kmem_cache_destroy(pq->txreq_cache);
+		kmem_cache_destroy(pq->txreq_cache);
 		kfree(pq);
 		fd->pq = NULL;
 	}

RE: [PATCH 11/39] hfi1: drop null test before destroy functions

[Marciniszyn, Mike]

> Subject: [PATCH 11/39] hfi1: drop null test before destroy functions
> 
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Thanks for the patch!

Acked-by: Mike Marciniszyn <mike.marciniszyn@intel.com>

[PATCH 12/39] dm: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/md/dm-bufio.c              |    3 +--
 drivers/md/dm-cache-target.c       |    3 +--
 drivers/md/dm-crypt.c              |    6 ++----
 drivers/md/dm-io.c                 |    3 +--
 drivers/md/dm-log-userspace-base.c |    3 +--
 drivers/md/dm-region-hash.c        |    4 +---
 drivers/md/dm.c                    |   13 ++++---------
 7 files changed, 11 insertions(+), 24 deletions(-)

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 83cc52e..8ad39b6 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -1864,8 +1864,7 @@ static void __exit dm_bufio_exit(void)
 	for (i = 0; i < ARRAY_SIZE(dm_bufio_caches); i++) {
 		struct kmem_cache *kc = dm_bufio_caches[i];
 
-		if (kc)
-			kmem_cache_destroy(kc);
+		kmem_cache_destroy(kc);
 	}
 
 	for (i = 0; i < ARRAY_SIZE(dm_bufio_cache_names); i++)
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 6264781..163de31 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2220,10 +2220,8 @@ static void cleanup_mapped_device(struct mapped_device *md)
 		destroy_workqueue(md->wq);
 	if (md->kworker_task)
 		kthread_stop(md->kworker_task);
-	if (md->io_pool)
-		mempool_destroy(md->io_pool);
-	if (md->rq_pool)
-		mempool_destroy(md->rq_pool);
+	mempool_destroy(md->io_pool);
+	mempool_destroy(md->rq_pool);
 	if (md->bs)
 		bioset_free(md->bs);
 
@@ -3508,11 +3506,8 @@ void dm_free_md_mempools(struct dm_md_mempools *pools)
 	if (!pools)
 		return;
 
-	if (pools->io_pool)
-		mempool_destroy(pools->io_pool);
-
-	if (pools->rq_pool)
-		mempool_destroy(pools->rq_pool);
+	mempool_destroy(pools->io_pool);
+	mempool_destroy(pools->rq_pool);
 
 	if (pools->bs)
 		bioset_free(pools->bs);
diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
index 058256d..53b7b06 100644
--- a/drivers/md/dm-log-userspace-base.c
+++ b/drivers/md/dm-log-userspace-base.c
@@ -313,8 +313,7 @@ static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
 out:
 	kfree(devices_rdata);
 	if (r) {
-		if (lc->flush_entry_pool)
-			mempool_destroy(lc->flush_entry_pool);
+		mempool_destroy(lc->flush_entry_pool);
 		kfree(lc);
 		kfree(ctr_str);
 	} else {
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 6f8e83b..81c5e1a 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -65,8 +65,7 @@ struct dm_io_client *dm_io_client_create(void)
 	return client;
 
    bad:
-	if (client->pool)
-		mempool_destroy(client->pool);
+	mempool_destroy(client->pool);
 	kfree(client);
 	return ERR_PTR(-ENOMEM);
 }
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index dd90d12..2fd4c82 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -2309,8 +2309,7 @@ static void destroy(struct cache *cache)
 {
 	unsigned i;
 
-	if (cache->migration_pool)
-		mempool_destroy(cache->migration_pool);
+	mempool_destroy(cache->migration_pool);
 
 	if (cache->all_io_ds)
 		dm_deferred_set_destroy(cache->all_io_ds);
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index d60c88d..cf91a96 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1543,10 +1543,8 @@ static void crypt_dtr(struct dm_target *ti)
 	if (cc->bs)
 		bioset_free(cc->bs);
 
-	if (cc->page_pool)
-		mempool_destroy(cc->page_pool);
-	if (cc->req_pool)
-		mempool_destroy(cc->req_pool);
+	mempool_destroy(cc->page_pool);
+	mempool_destroy(cc->req_pool);
 
 	if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
 		cc->iv_gen_ops->dtr(cc);
diff --git a/drivers/md/dm-region-hash.c b/drivers/md/dm-region-hash.c
index b929fd5..f3d608b 100644
--- a/drivers/md/dm-region-hash.c
+++ b/drivers/md/dm-region-hash.c
@@ -249,9 +249,7 @@ void dm_region_hash_destroy(struct dm_region_hash *rh)
 	if (rh->log)
 		dm_dirty_log_destroy(rh->log);
 
-	if (rh->region_pool)
-		mempool_destroy(rh->region_pool);
-
+	mempool_destroy(rh->region_pool);
 	vfree(rh->buckets);
 	kfree(rh);
 }

Re: [dm-devel] [PATCH 12/39] dm: drop null test before destroy functions

[Mikulas Patocka]

On Sun, 13 Sep 2015, Julia Lawall wrote:

> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  drivers/md/dm-bufio.c              |    3 +--
>  drivers/md/dm-cache-target.c       |    3 +--
>  drivers/md/dm-crypt.c              |    6 ++----
>  drivers/md/dm-io.c                 |    3 +--
>  drivers/md/dm-log-userspace-base.c |    3 +--
>  drivers/md/dm-region-hash.c        |    4 +---
>  drivers/md/dm.c                    |   13 ++++---------
>  7 files changed, 11 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
> index 83cc52e..8ad39b6 100644
> --- a/drivers/md/dm-bufio.c
> +++ b/drivers/md/dm-bufio.c
> @@ -1864,8 +1864,7 @@ static void __exit dm_bufio_exit(void)
>  	for (i = 0; i < ARRAY_SIZE(dm_bufio_caches); i++) {
>  		struct kmem_cache *kc = dm_bufio_caches[i];
>  
> -		if (kc)
> -			kmem_cache_destroy(kc);
> +		kmem_cache_destroy(kc);
>  	}

The variable here can be NULL. I don't know how did you conclude that it 
cannot. It seems that you didn't test the patch, if you did, you'd hit 
NULL pointer dereference here.

>  	for (i = 0; i < ARRAY_SIZE(dm_bufio_cache_names); i++)
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index 6264781..163de31 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -2220,10 +2220,8 @@ static void cleanup_mapped_device(struct mapped_device *md)
>  		destroy_workqueue(md->wq);
>  	if (md->kworker_task)
>  		kthread_stop(md->kworker_task);
> -	if (md->io_pool)
> -		mempool_destroy(md->io_pool);
> -	if (md->rq_pool)
> -		mempool_destroy(md->rq_pool);
> +	mempool_destroy(md->io_pool);
> +	mempool_destroy(md->rq_pool);

Likewise, these variables can be NULL.

>  	if (md->bs)
>  		bioset_free(md->bs);
>  
> @@ -3508,11 +3506,8 @@ void dm_free_md_mempools(struct dm_md_mempools *pools)
>  	if (!pools)
>  		return;
>  
> -	if (pools->io_pool)
> -		mempool_destroy(pools->io_pool);
> -
> -	if (pools->rq_pool)
> -		mempool_destroy(pools->rq_pool);
> +	mempool_destroy(pools->io_pool);
> +	mempool_destroy(pools->rq_pool);
>  
>  	if (pools->bs)
>  		bioset_free(pools->bs);

Likewise, it can be NULL, see for example this code path:
                pools->io_pool = mempool_create_slab_pool(pool_size, cachep);
                if (!pools->io_pool)
                        goto out;
out:
        dm_free_md_mempools(pools);
dm_free_md_mempools:
        if (pools->io_pool)
                mempool_destroy(pools->io_pool);

It seems that you set up the cocinelle tool incorrectly, so that it 
produces many bogus suggestions.

Mikulas

> diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
> index 058256d..53b7b06 100644
> --- a/drivers/md/dm-log-userspace-base.c
> +++ b/drivers/md/dm-log-userspace-base.c
> @@ -313,8 +313,7 @@ static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
>  out:
>  	kfree(devices_rdata);
>  	if (r) {
> -		if (lc->flush_entry_pool)
> -			mempool_destroy(lc->flush_entry_pool);
> +		mempool_destroy(lc->flush_entry_pool);
>  		kfree(lc);
>  		kfree(ctr_str);
>  	} else {
> diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
> index 6f8e83b..81c5e1a 100644
> --- a/drivers/md/dm-io.c
> +++ b/drivers/md/dm-io.c
> @@ -65,8 +65,7 @@ struct dm_io_client *dm_io_client_create(void)
>  	return client;
>  
>     bad:
> -	if (client->pool)
> -		mempool_destroy(client->pool);
> +	mempool_destroy(client->pool);
>  	kfree(client);
>  	return ERR_PTR(-ENOMEM);
>  }
> diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
> index dd90d12..2fd4c82 100644
> --- a/drivers/md/dm-cache-target.c
> +++ b/drivers/md/dm-cache-target.c
> @@ -2309,8 +2309,7 @@ static void destroy(struct cache *cache)
>  {
>  	unsigned i;
>  
> -	if (cache->migration_pool)
> -		mempool_destroy(cache->migration_pool);
> +	mempool_destroy(cache->migration_pool);
>  
>  	if (cache->all_io_ds)
>  		dm_deferred_set_destroy(cache->all_io_ds);
> diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
> index d60c88d..cf91a96 100644
> --- a/drivers/md/dm-crypt.c
> +++ b/drivers/md/dm-crypt.c
> @@ -1543,10 +1543,8 @@ static void crypt_dtr(struct dm_target *ti)
>  	if (cc->bs)
>  		bioset_free(cc->bs);
>  
> -	if (cc->page_pool)
> -		mempool_destroy(cc->page_pool);
> -	if (cc->req_pool)
> -		mempool_destroy(cc->req_pool);
> +	mempool_destroy(cc->page_pool);
> +	mempool_destroy(cc->req_pool);
>  
>  	if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
>  		cc->iv_gen_ops->dtr(cc);
> diff --git a/drivers/md/dm-region-hash.c b/drivers/md/dm-region-hash.c
> index b929fd5..f3d608b 100644
> --- a/drivers/md/dm-region-hash.c
> +++ b/drivers/md/dm-region-hash.c
> @@ -249,9 +249,7 @@ void dm_region_hash_destroy(struct dm_region_hash *rh)
>  	if (rh->log)
>  		dm_dirty_log_destroy(rh->log);
>  
> -	if (rh->region_pool)
> -		mempool_destroy(rh->region_pool);
> -
> +	mempool_destroy(rh->region_pool);
>  	vfree(rh->buckets);
>  	kfree(rh);
>  }
> 
> --
> dm-devel mailing list
> dm-devel@redhat.com
> https://www.redhat.com/mailman/listinfo/dm-devel
> 

Re: [PATCH 12/39] dm: drop null test before destroy functions

[Mike Snitzer]

On Mon, Sep 14 2015 at  9:46am -0400,
Mikulas Patocka <mpatocka@redhat.com> wrote:

> 
> 
> On Sun, 13 Sep 2015, Julia Lawall wrote:
> 
> > Remove unneeded NULL test.
> > 
> > The semantic patch that makes this change is as follows:
> > (http://coccinelle.lip6.fr/)
> > 
> > // <smpl>
> > @@ expression x; @@
> > -if (x != NULL)
> >   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> > // </smpl>
> > 
> > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> > 
> > ---
> >  drivers/md/dm-bufio.c              |    3 +--
> >  drivers/md/dm-cache-target.c       |    3 +--
> >  drivers/md/dm-crypt.c              |    6 ++----
> >  drivers/md/dm-io.c                 |    3 +--
> >  drivers/md/dm-log-userspace-base.c |    3 +--
> >  drivers/md/dm-region-hash.c        |    4 +---
> >  drivers/md/dm.c                    |   13 ++++---------
> >  7 files changed, 11 insertions(+), 24 deletions(-)
> > 
> > diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
> > index 83cc52e..8ad39b6 100644
> > --- a/drivers/md/dm-bufio.c
> > +++ b/drivers/md/dm-bufio.c
> > @@ -1864,8 +1864,7 @@ static void __exit dm_bufio_exit(void)
> >  	for (i = 0; i < ARRAY_SIZE(dm_bufio_caches); i++) {
> >  		struct kmem_cache *kc = dm_bufio_caches[i];
> >  
> > -		if (kc)
> > -			kmem_cache_destroy(kc);
> > +		kmem_cache_destroy(kc);
> >  	}
> 
> The variable here can be NULL. I don't know how did you conclude that it 
> cannot. It seems that you didn't test the patch, if you did, you'd hit 
> NULL pointer dereference here.

kmem_cache_destroy(), mempool_destroy(), etc all check for NULL and just
return.  So there is no need for the callers to check for NULL too.

Mike

Re: [PATCH 12/39] dm: drop null test before destroy functions

[Mikulas Patocka]

On Mon, 14 Sep 2015, Mike Snitzer wrote:

> On Mon, Sep 14 2015 at  9:46am -0400,
> Mikulas Patocka <mpatocka@redhat.com> wrote:
> 
> > 
> > 
> > On Sun, 13 Sep 2015, Julia Lawall wrote:
> > 
> > > Remove unneeded NULL test.
> > > 
> > > The semantic patch that makes this change is as follows:
> > > (http://coccinelle.lip6.fr/)
> > > 
> > > // <smpl>
> > > @@ expression x; @@
> > > -if (x != NULL)
> > >   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> > > // </smpl>
> > > 
> > > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> > > 
> > > ---
> > >  drivers/md/dm-bufio.c              |    3 +--
> > >  drivers/md/dm-cache-target.c       |    3 +--
> > >  drivers/md/dm-crypt.c              |    6 ++----
> > >  drivers/md/dm-io.c                 |    3 +--
> > >  drivers/md/dm-log-userspace-base.c |    3 +--
> > >  drivers/md/dm-region-hash.c        |    4 +---
> > >  drivers/md/dm.c                    |   13 ++++---------
> > >  7 files changed, 11 insertions(+), 24 deletions(-)
> > > 
> > > diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
> > > index 83cc52e..8ad39b6 100644
> > > --- a/drivers/md/dm-bufio.c
> > > +++ b/drivers/md/dm-bufio.c
> > > @@ -1864,8 +1864,7 @@ static void __exit dm_bufio_exit(void)
> > >  	for (i = 0; i < ARRAY_SIZE(dm_bufio_caches); i++) {
> > >  		struct kmem_cache *kc = dm_bufio_caches[i];
> > >  
> > > -		if (kc)
> > > -			kmem_cache_destroy(kc);
> > > +		kmem_cache_destroy(kc);
> > >  	}
> > 
> > The variable here can be NULL. I don't know how did you conclude that it 
> > cannot. It seems that you didn't test the patch, if you did, you'd hit 
> > NULL pointer dereference here.
> 
> kmem_cache_destroy(), mempool_destroy(), etc all check for NULL and just
> return.  So there is no need for the callers to check for NULL too.
> 
> Mike

I see. It was recent change that I missed.

Mikulas

Re: [PATCH 12/39] dm: drop null test before destroy functions

[Julia Lawall]

On Mon, 14 Sep 2015, Mikulas Patocka wrote:

> 
> 
> On Mon, 14 Sep 2015, Mike Snitzer wrote:
> 
> > On Mon, Sep 14 2015 at  9:46am -0400,
> > Mikulas Patocka <mpatocka@redhat.com> wrote:
> > 
> > > 
> > > 
> > > On Sun, 13 Sep 2015, Julia Lawall wrote:
> > > 
> > > > Remove unneeded NULL test.
> > > > 
> > > > The semantic patch that makes this change is as follows:
> > > > (http://coccinelle.lip6.fr/)
> > > > 
> > > > // <smpl>
> > > > @@ expression x; @@
> > > > -if (x != NULL)
> > > >   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> > > > // </smpl>
> > > > 
> > > > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> > > > 
> > > > ---
> > > >  drivers/md/dm-bufio.c              |    3 +--
> > > >  drivers/md/dm-cache-target.c       |    3 +--
> > > >  drivers/md/dm-crypt.c              |    6 ++----
> > > >  drivers/md/dm-io.c                 |    3 +--
> > > >  drivers/md/dm-log-userspace-base.c |    3 +--
> > > >  drivers/md/dm-region-hash.c        |    4 +---
> > > >  drivers/md/dm.c                    |   13 ++++---------
> > > >  7 files changed, 11 insertions(+), 24 deletions(-)
> > > > 
> > > > diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
> > > > index 83cc52e..8ad39b6 100644
> > > > --- a/drivers/md/dm-bufio.c
> > > > +++ b/drivers/md/dm-bufio.c
> > > > @@ -1864,8 +1864,7 @@ static void __exit dm_bufio_exit(void)
> > > >  	for (i = 0; i < ARRAY_SIZE(dm_bufio_caches); i++) {
> > > >  		struct kmem_cache *kc = dm_bufio_caches[i];
> > > >  
> > > > -		if (kc)
> > > > -			kmem_cache_destroy(kc);
> > > > +		kmem_cache_destroy(kc);
> > > >  	}
> > > 
> > > The variable here can be NULL. I don't know how did you conclude that it 
> > > cannot. It seems that you didn't test the patch, if you did, you'd hit 
> > > NULL pointer dereference here.
> > 
> > kmem_cache_destroy(), mempool_destroy(), etc all check for NULL and just
> > return.  So there is no need for the callers to check for NULL too.
> > 
> > Mike
> 
> I see. It was recent change that I missed.

The relevant commits were in the cover letter:

kmem_cache_destroy (commit 3942d29918522)
mempool_destroy (commit 4e3ca3e033d1)
dma_pool_destroy (commit 44d7175da6ea)

julia

Re: [dm-devel] [PATCH 12/39] dm: drop null test before destroy functions

[walter harms]

Am 14.09.2015 15:46, schrieb Mikulas Patocka:
> 
> On Sun, 13 Sep 2015, Julia Lawall wrote:
> 
>> > Remove unneeded NULL test.
>> > 
>> > The semantic patch that makes this change is as follows:
>> > (http://coccinelle.lip6.fr/)
>> > 
>> > // <smpl>
>> > @@ expression x; @@
>> > -if (x != NULL)
>> >   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>> > // </smpl>
>> > 
>> > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>> > 
>> > ---
>> >  drivers/md/dm-bufio.c              |    3 +--
>> >  drivers/md/dm-cache-target.c       |    3 +--
>> >  drivers/md/dm-crypt.c              |    6 ++----
>> >  drivers/md/dm-io.c                 |    3 +--
>> >  drivers/md/dm-log-userspace-base.c |    3 +--
>> >  drivers/md/dm-region-hash.c        |    4 +---
>> >  drivers/md/dm.c                    |   13 ++++---------
>> >  7 files changed, 11 insertions(+), 24 deletions(-)
>> > 
>> > diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
>> > index 83cc52e..8ad39b6 100644
>> > --- a/drivers/md/dm-bufio.c
>> > +++ b/drivers/md/dm-bufio.c
>> > @@ -1864,8 +1864,7 @@ static void __exit dm_bufio_exit(void)
>> >  	for (i = 0; i < ARRAY_SIZE(dm_bufio_caches); i++) {
>> >  		struct kmem_cache *kc = dm_bufio_caches[i];
>> >  
>> > -		if (kc)
>> > -			kmem_cache_destroy(kc);
>> > +		kmem_cache_destroy(kc);
>> >  	}


maybe you want to remove "kc" also
by calling kmem_cache_destroy(dm_bufio_caches[i]); directly ?

just a hint,
 wh

[PATCH 13/39] staging: lustre: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);

@@
expression x;
@@

-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/staging/lustre/lustre/llite/super25.c      |   16 +++-----------
 drivers/staging/lustre/lustre/obdclass/genops.c    |   24 +++++++--------------
 drivers/staging/lustre/lustre/obdclass/lu_object.c |    6 +----
 3 files changed, 14 insertions(+), 32 deletions(-)

diff --git a/drivers/staging/lustre/lustre/obdclass/lu_object.c b/drivers/staging/lustre/lustre/obdclass/lu_object.c
index 8e47232..e8101fe 100644
--- a/drivers/staging/lustre/lustre/obdclass/lu_object.c
+++ b/drivers/staging/lustre/lustre/obdclass/lu_object.c
@@ -2052,10 +2052,8 @@ EXPORT_SYMBOL(lu_kmem_init);
 void lu_kmem_fini(struct lu_kmem_descr *caches)
 {
 	for (; caches->ckd_cache != NULL; ++caches) {
-		if (*caches->ckd_cache != NULL) {
-			kmem_cache_destroy(*caches->ckd_cache);
-			*caches->ckd_cache = NULL;
-		}
+		kmem_cache_destroy(*caches->ckd_cache);
+		*caches->ckd_cache = NULL;
 	}
 }
 EXPORT_SYMBOL(lu_kmem_fini);
diff --git a/drivers/staging/lustre/lustre/obdclass/genops.c b/drivers/staging/lustre/lustre/obdclass/genops.c
index 0ca7309..ad78a04 100644
--- a/drivers/staging/lustre/lustre/obdclass/genops.c
+++ b/drivers/staging/lustre/lustre/obdclass/genops.c
@@ -638,22 +638,14 @@ EXPORT_SYMBOL(class_notify_sptlrpc_conf);
 
 void obd_cleanup_caches(void)
 {
-	if (obd_device_cachep) {
-		kmem_cache_destroy(obd_device_cachep);
-		obd_device_cachep = NULL;
-	}
-	if (obdo_cachep) {
-		kmem_cache_destroy(obdo_cachep);
-		obdo_cachep = NULL;
-	}
-	if (import_cachep) {
-		kmem_cache_destroy(import_cachep);
-		import_cachep = NULL;
-	}
-	if (capa_cachep) {
-		kmem_cache_destroy(capa_cachep);
-		capa_cachep = NULL;
-	}
+	kmem_cache_destroy(obd_device_cachep);
+	obd_device_cachep = NULL;
+	kmem_cache_destroy(obdo_cachep);
+	obdo_cachep = NULL;
+	kmem_cache_destroy(import_cachep);
+	import_cachep = NULL;
+	kmem_cache_destroy(capa_cachep);
+	capa_cachep = NULL;
 }
 
 int obd_init_caches(void)
diff --git a/drivers/staging/lustre/lustre/llite/super25.c b/drivers/staging/lustre/lustre/llite/super25.c
index e4020ce..4cf7af2 100644
--- a/drivers/staging/lustre/lustre/llite/super25.c
+++ b/drivers/staging/lustre/lustre/llite/super25.c
@@ -183,18 +183,10 @@ out_sysfs:
 out_debugfs:
 	debugfs_remove(llite_root);
 out_cache:
-	if (ll_inode_cachep != NULL)
-		kmem_cache_destroy(ll_inode_cachep);
-
-	if (ll_file_data_slab != NULL)
-		kmem_cache_destroy(ll_file_data_slab);
-
-	if (ll_remote_perm_cachep != NULL)
-		kmem_cache_destroy(ll_remote_perm_cachep);
-
-	if (ll_rmtperm_hash_cachep != NULL)
-		kmem_cache_destroy(ll_rmtperm_hash_cachep);
-
+	kmem_cache_destroy(ll_inode_cachep);
+	kmem_cache_destroy(ll_file_data_slab);
+	kmem_cache_destroy(ll_remote_perm_cachep);
+	kmem_cache_destroy(ll_rmtperm_hash_cachep);
 	return rc;
 }
 

[PATCH 14/39] SUNRPC: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 net/sunrpc/sched.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index b140c09..425ca2f 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -1092,14 +1092,10 @@ void
 rpc_destroy_mempool(void)
 {
 	rpciod_stop();
-	if (rpc_buffer_mempool)
-		mempool_destroy(rpc_buffer_mempool);
-	if (rpc_task_mempool)
-		mempool_destroy(rpc_task_mempool);
-	if (rpc_task_slabp)
-		kmem_cache_destroy(rpc_task_slabp);
-	if (rpc_buffer_slabp)
-		kmem_cache_destroy(rpc_buffer_slabp);
+	mempool_destroy(rpc_buffer_mempool);
+	mempool_destroy(rpc_task_mempool);
+	kmem_cache_destroy(rpc_task_slabp);
+	kmem_cache_destroy(rpc_buffer_slabp);
 	rpc_destroy_wait_queue(&delay_queue);
 }
 

Re: [PATCH 14/39] SUNRPC: drop null test before destroy functions

[J. Bruce Fields]

ACK, but assuming Trond takes this one.--b.

On Sun, Sep 13, 2015 at 02:15:07PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  net/sunrpc/sched.c |   12 ++++--------
>  1 file changed, 4 insertions(+), 8 deletions(-)
> 
> diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
> index b140c09..425ca2f 100644
> --- a/net/sunrpc/sched.c
> +++ b/net/sunrpc/sched.c
> @@ -1092,14 +1092,10 @@ void
>  rpc_destroy_mempool(void)
>  {
>  	rpciod_stop();
> -	if (rpc_buffer_mempool)
> -		mempool_destroy(rpc_buffer_mempool);
> -	if (rpc_task_mempool)
> -		mempool_destroy(rpc_task_mempool);
> -	if (rpc_task_slabp)
> -		kmem_cache_destroy(rpc_task_slabp);
> -	if (rpc_buffer_slabp)
> -		kmem_cache_destroy(rpc_buffer_slabp);
> +	mempool_destroy(rpc_buffer_mempool);
> +	mempool_destroy(rpc_task_mempool);
> +	kmem_cache_destroy(rpc_task_slabp);
> +	kmem_cache_destroy(rpc_buffer_slabp);
>  	rpc_destroy_wait_queue(&delay_queue);
>  }
>  

Re: [PATCH 14/39] SUNRPC: drop null test before destroy functions

[Trond Myklebust]

On Mon, Sep 14, 2015 at 12:07 PM, J. Bruce Fields <bfields@fieldses.org> wrote:
> ACK, but assuming Trond takes this one.--b.

No problem. I'll pick it up...

Cheers
  Trond

> On Sun, Sep 13, 2015 at 02:15:07PM +0200, Julia Lawall wrote:
>> Remove unneeded NULL test.
>>
>> The semantic patch that makes this change is as follows:
>> (http://coccinelle.lip6.fr/)
>>
>> // <smpl>
>> @@ expression x; @@
>> -if (x != NULL)
>>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>> // </smpl>
>>
>> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>>
>> ---
>>  net/sunrpc/sched.c |   12 ++++--------
>>  1 file changed, 4 insertions(+), 8 deletions(-)
>>
>> diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
>> index b140c09..425ca2f 100644
>> --- a/net/sunrpc/sched.c
>> +++ b/net/sunrpc/sched.c
>> @@ -1092,14 +1092,10 @@ void
>>  rpc_destroy_mempool(void)
>>  {
>>       rpciod_stop();
>> -     if (rpc_buffer_mempool)
>> -             mempool_destroy(rpc_buffer_mempool);
>> -     if (rpc_task_mempool)
>> -             mempool_destroy(rpc_task_mempool);
>> -     if (rpc_task_slabp)
>> -             kmem_cache_destroy(rpc_task_slabp);
>> -     if (rpc_buffer_slabp)
>> -             kmem_cache_destroy(rpc_buffer_slabp);
>> +     mempool_destroy(rpc_buffer_mempool);
>> +     mempool_destroy(rpc_task_mempool);
>> +     kmem_cache_destroy(rpc_task_slabp);
>> +     kmem_cache_destroy(rpc_buffer_slabp);
>>       rpc_destroy_wait_queue(&delay_queue);
>>  }
>>

[PATCH 15/39] bcache: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/md/bcache/bset.c    |    3 +--
 drivers/md/bcache/request.c |    3 +--
 drivers/md/bcache/super.c   |    9 +++------
 3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 8e9877b..bd4678c 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1145,8 +1145,7 @@ void bch_flash_dev_request_init(struct bcache_device *d)
 
 void bch_request_exit(void)
 {
-	if (bch_search_cache)
-		kmem_cache_destroy(bch_search_cache);
+	kmem_cache_destroy(bch_search_cache);
 }
 
 int __init bch_request_init(void)
diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index 646fe85..479117c 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -1116,8 +1116,7 @@ struct bkey *bch_btree_iter_next_filter(struct btree_iter *iter,
 
 void bch_bset_sort_state_free(struct bset_sort_state *state)
 {
-	if (state->pool)
-		mempool_destroy(state->pool);
+	mempool_destroy(state->pool);
 }
 
 int bch_bset_sort_state_init(struct bset_sort_state *state, unsigned page_order)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 679a093..c27a0ff 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1335,12 +1335,9 @@ static void cache_set_free(struct closure *cl)
 		destroy_workqueue(c->moving_gc_wq);
 	if (c->bio_split)
 		bioset_free(c->bio_split);
-	if (c->fill_iter)
-		mempool_destroy(c->fill_iter);
-	if (c->bio_meta)
-		mempool_destroy(c->bio_meta);
-	if (c->search)
-		mempool_destroy(c->search);
+	mempool_destroy(c->fill_iter);
+	mempool_destroy(c->bio_meta);
+	mempool_destroy(c->search);
 	kfree(c->devices);
 
 	mutex_lock(&bch_register_lock);

Re: [PATCH 15/39] bcache: drop null test before destroy functions

[Johannes Thumshirn]

Julia Lawall <Julia.Lawall@lip6.fr> writes:

> Remove unneeded NULL test.
>
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

>
> ---
>  drivers/md/bcache/bset.c    |    3 +--
>  drivers/md/bcache/request.c |    3 +--
>  drivers/md/bcache/super.c   |    9 +++------
>  3 files changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> index 8e9877b..bd4678c 100644
> --- a/drivers/md/bcache/request.c
> +++ b/drivers/md/bcache/request.c
> @@ -1145,8 +1145,7 @@ void bch_flash_dev_request_init(struct bcache_device *d)
>  
>  void bch_request_exit(void)
>  {
> -	if (bch_search_cache)
> -		kmem_cache_destroy(bch_search_cache);
> +	kmem_cache_destroy(bch_search_cache);
>  }
>  
>  int __init bch_request_init(void)
> diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
> index 646fe85..479117c 100644
> --- a/drivers/md/bcache/bset.c
> +++ b/drivers/md/bcache/bset.c
> @@ -1116,8 +1116,7 @@ struct bkey *bch_btree_iter_next_filter(struct btree_iter *iter,
>  
>  void bch_bset_sort_state_free(struct bset_sort_state *state)
>  {
> -	if (state->pool)
> -		mempool_destroy(state->pool);
> +	mempool_destroy(state->pool);
>  }
>  
>  int bch_bset_sort_state_init(struct bset_sort_state *state, unsigned page_order)
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index 679a093..c27a0ff 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -1335,12 +1335,9 @@ static void cache_set_free(struct closure *cl)
>  		destroy_workqueue(c->moving_gc_wq);
>  	if (c->bio_split)
>  		bioset_free(c->bio_split);
> -	if (c->fill_iter)
> -		mempool_destroy(c->fill_iter);
> -	if (c->bio_meta)
> -		mempool_destroy(c->bio_meta);
> -	if (c->search)
> -		mempool_destroy(c->search);
> +	mempool_destroy(c->fill_iter);
> +	mempool_destroy(c->bio_meta);
> +	mempool_destroy(c->search);
>  	kfree(c->devices);
>  
>  	mutex_lock(&bch_register_lock);
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bcache" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
Johannes Thumshirn                                           Storage
jthumshirn@suse.de                                 +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: Felix Imendörffer, Jane Smithard, Graham Norton
HRB 21284 (AG Nürnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600  D0D0 0393 969D 2D76 0850

[PATCH 16/39] usb: gadget: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/usb/gadget/udc/bdc/bdc_core.c |    3 +--
 drivers/usb/gadget/udc/gr_udc.c       |    3 +--
 drivers/usb/gadget/udc/mv_u3d_core.c  |    3 +--
 drivers/usb/gadget/udc/mv_udc_core.c  |    3 +--
 4 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/gadget/udc/mv_udc_core.c b/drivers/usb/gadget/udc/mv_udc_core.c
index 339af51..81b6229 100644
--- a/drivers/usb/gadget/udc/mv_udc_core.c
+++ b/drivers/usb/gadget/udc/mv_udc_core.c
@@ -2100,8 +2100,7 @@ static int mv_udc_remove(struct platform_device *pdev)
 	}
 
 	/* free memory allocated in probe */
-	if (udc->dtd_pool)
-		dma_pool_destroy(udc->dtd_pool);
+	dma_pool_destroy(udc->dtd_pool);
 
 	if (udc->ep_dqh)
 		dma_free_coherent(&pdev->dev, udc->ep_dqh_size,
diff --git a/drivers/usb/gadget/udc/gr_udc.c b/drivers/usb/gadget/udc/gr_udc.c
index 8aa2593..b9429bc 100644
--- a/drivers/usb/gadget/udc/gr_udc.c
+++ b/drivers/usb/gadget/udc/gr_udc.c
@@ -2117,8 +2117,7 @@ static int gr_remove(struct platform_device *pdev)
 		return -EBUSY;
 
 	gr_dfs_delete(dev);
-	if (dev->desc_pool)
-		dma_pool_destroy(dev->desc_pool);
+	dma_pool_destroy(dev->desc_pool);
 	platform_set_drvdata(pdev, NULL);
 
 	gr_free_request(&dev->epi[0].ep, &dev->ep0reqi->req);
diff --git a/drivers/usb/gadget/udc/mv_u3d_core.c b/drivers/usb/gadget/udc/mv_u3d_core.c
index 4c48969..dafe74e 100644
--- a/drivers/usb/gadget/udc/mv_u3d_core.c
+++ b/drivers/usb/gadget/udc/mv_u3d_core.c
@@ -1767,8 +1767,7 @@ static int mv_u3d_remove(struct platform_device *dev)
 	usb_del_gadget_udc(&u3d->gadget);
 
 	/* free memory allocated in probe */
-	if (u3d->trb_pool)
-		dma_pool_destroy(u3d->trb_pool);
+	dma_pool_destroy(u3d->trb_pool);
 
 	if (u3d->ep_context)
 		dma_free_coherent(&dev->dev, u3d->ep_context_size,
diff --git a/drivers/usb/gadget/udc/bdc/bdc_core.c b/drivers/usb/gadget/udc/bdc/bdc_core.c
index 5c8f4ef..ccb9c21 100644
--- a/drivers/usb/gadget/udc/bdc/bdc_core.c
+++ b/drivers/usb/gadget/udc/bdc/bdc_core.c
@@ -324,8 +324,7 @@ static void bdc_mem_free(struct bdc *bdc)
 				bdc->scratchpad.buff, bdc->scratchpad.sp_dma);
 
 	/* Destroy the dma pools */
-	if (bdc->bd_table_pool)
-		dma_pool_destroy(bdc->bd_table_pool);
+	dma_pool_destroy(bdc->bd_table_pool);
 
 	/* Free the bdc_ep array */
 	kfree(bdc->bdc_ep_array);

[PATCH 17/39] md: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/md/multipath.c |    3 +--
 drivers/md/raid1.c     |    6 ++----
 drivers/md/raid10.c    |    9 +++------
 drivers/md/raid5.c     |    3 +--
 4 files changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 15ef2c6..09a12d7 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2271,8 +2271,7 @@ static void shrink_stripes(struct r5conf *conf)
 	       drop_one_stripe(conf))
 		;
 
-	if (conf->slab_cache)
-		kmem_cache_destroy(conf->slab_cache);
+	kmem_cache_destroy(conf->slab_cache);
 	conf->slab_cache = NULL;
 }
 
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 4517f06..5f4f553 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2843,8 +2843,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
 
  abort:
 	if (conf) {
-		if (conf->r1bio_pool)
-			mempool_destroy(conf->r1bio_pool);
+		mempool_destroy(conf->r1bio_pool);
 		kfree(conf->mirrors);
 		safe_put_page(conf->tmppage);
 		kfree(conf->poolinfo);
@@ -2946,8 +2945,7 @@ static void raid1_free(struct mddev *mddev, void *priv)
 {
 	struct r1conf *conf = priv;
 
-	if (conf->r1bio_pool)
-		mempool_destroy(conf->r1bio_pool);
+	mempool_destroy(conf->r1bio_pool);
 	kfree(conf->mirrors);
 	safe_put_page(conf->tmppage);
 	kfree(conf->poolinfo);
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index d222522..d132f06 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -470,8 +470,7 @@ static int multipath_run (struct mddev *mddev)
 	return 0;
 
 out_free_conf:
-	if (conf->pool)
-		mempool_destroy(conf->pool);
+	mempool_destroy(conf->pool);
 	kfree(conf->multipaths);
 	kfree(conf);
 	mddev->private = NULL;
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 0fc33eb..7c99a40 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3486,8 +3486,7 @@ static struct r10conf *setup_conf(struct mddev *mddev)
 		printk(KERN_ERR "md/raid10:%s: couldn't allocate memory.\n",
 		       mdname(mddev));
 	if (conf) {
-		if (conf->r10bio_pool)
-			mempool_destroy(conf->r10bio_pool);
+		mempool_destroy(conf->r10bio_pool);
 		kfree(conf->mirrors);
 		safe_put_page(conf->tmppage);
 		kfree(conf);
@@ -3682,8 +3681,7 @@ static int run(struct mddev *mddev)
 
 out_free_conf:
 	md_unregister_thread(&mddev->thread);
-	if (conf->r10bio_pool)
-		mempool_destroy(conf->r10bio_pool);
+	mempool_destroy(conf->r10bio_pool);
 	safe_put_page(conf->tmppage);
 	kfree(conf->mirrors);
 	kfree(conf);
@@ -3696,8 +3694,7 @@ static void raid10_free(struct mddev *mddev, void *priv)
 {
 	struct r10conf *conf = priv;
 
-	if (conf->r10bio_pool)
-		mempool_destroy(conf->r10bio_pool);
+	mempool_destroy(conf->r10bio_pool);
 	safe_put_page(conf->tmppage);
 	kfree(conf->mirrors);
 	kfree(conf->mirrors_old);

Re: [PATCH 17/39] md: drop null test before destroy functions

[Neil Brown]

[-- Attachment #1: Type: text/plain, Size: 3464 bytes --]

Julia Lawall <Julia.Lawall@lip6.fr> writes:

> Remove unneeded NULL test.
>
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>
> ---
>  drivers/md/multipath.c |    3 +--
>  drivers/md/raid1.c     |    6 ++----
>  drivers/md/raid10.c    |    9 +++------
>  drivers/md/raid5.c     |    3 +--
>  4 files changed, 7 insertions(+), 14 deletions(-)

Applied, thanks.

NeilBrown


>
> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
> index 15ef2c6..09a12d7 100644
> --- a/drivers/md/raid5.c
> +++ b/drivers/md/raid5.c
> @@ -2271,8 +2271,7 @@ static void shrink_stripes(struct r5conf *conf)
>  	       drop_one_stripe(conf))
>  		;
>  
> -	if (conf->slab_cache)
> -		kmem_cache_destroy(conf->slab_cache);
> +	kmem_cache_destroy(conf->slab_cache);
>  	conf->slab_cache = NULL;
>  }
>  
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index 4517f06..5f4f553 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -2843,8 +2843,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
>  
>   abort:
>  	if (conf) {
> -		if (conf->r1bio_pool)
> -			mempool_destroy(conf->r1bio_pool);
> +		mempool_destroy(conf->r1bio_pool);
>  		kfree(conf->mirrors);
>  		safe_put_page(conf->tmppage);
>  		kfree(conf->poolinfo);
> @@ -2946,8 +2945,7 @@ static void raid1_free(struct mddev *mddev, void *priv)
>  {
>  	struct r1conf *conf = priv;
>  
> -	if (conf->r1bio_pool)
> -		mempool_destroy(conf->r1bio_pool);
> +	mempool_destroy(conf->r1bio_pool);
>  	kfree(conf->mirrors);
>  	safe_put_page(conf->tmppage);
>  	kfree(conf->poolinfo);
> diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
> index d222522..d132f06 100644
> --- a/drivers/md/multipath.c
> +++ b/drivers/md/multipath.c
> @@ -470,8 +470,7 @@ static int multipath_run (struct mddev *mddev)
>  	return 0;
>  
>  out_free_conf:
> -	if (conf->pool)
> -		mempool_destroy(conf->pool);
> +	mempool_destroy(conf->pool);
>  	kfree(conf->multipaths);
>  	kfree(conf);
>  	mddev->private = NULL;
> diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
> index 0fc33eb..7c99a40 100644
> --- a/drivers/md/raid10.c
> +++ b/drivers/md/raid10.c
> @@ -3486,8 +3486,7 @@ static struct r10conf *setup_conf(struct mddev *mddev)
>  		printk(KERN_ERR "md/raid10:%s: couldn't allocate memory.\n",
>  		       mdname(mddev));
>  	if (conf) {
> -		if (conf->r10bio_pool)
> -			mempool_destroy(conf->r10bio_pool);
> +		mempool_destroy(conf->r10bio_pool);
>  		kfree(conf->mirrors);
>  		safe_put_page(conf->tmppage);
>  		kfree(conf);
> @@ -3682,8 +3681,7 @@ static int run(struct mddev *mddev)
>  
>  out_free_conf:
>  	md_unregister_thread(&mddev->thread);
> -	if (conf->r10bio_pool)
> -		mempool_destroy(conf->r10bio_pool);
> +	mempool_destroy(conf->r10bio_pool);
>  	safe_put_page(conf->tmppage);
>  	kfree(conf->mirrors);
>  	kfree(conf);
> @@ -3696,8 +3694,7 @@ static void raid10_free(struct mddev *mddev, void *priv)
>  {
>  	struct r10conf *conf = priv;
>  
> -	if (conf->r10bio_pool)
> -		mempool_destroy(conf->r10bio_pool);
> +	mempool_destroy(conf->r10bio_pool);
>  	safe_put_page(conf->tmppage);
>  	kfree(conf->mirrors);
>  	kfree(conf->mirrors_old);

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 818 bytes --]

[PATCH 18/39] whci: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/usb/host/whci/init.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/host/whci/init.c b/drivers/usb/host/whci/init.c
index d3e13b6..e363723 100644
--- a/drivers/usb/host/whci/init.c
+++ b/drivers/usb/host/whci/init.c
@@ -175,8 +175,7 @@ void whc_clean_up(struct whc *whc)
 	pzl_clean_up(whc);
 	asl_clean_up(whc);
 
-	if (whc->qset_pool)
-		dma_pool_destroy(whc->qset_pool);
+	dma_pool_destroy(whc->qset_pool);
 
 	len   = resource_size(&whc->umc->resource);
 	if (whc->base)

[PATCH 19/39] jbd2: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);

@@
expression x;
@@

-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/jbd2/journal.c     |   15 +++++----------
 fs/jbd2/revoke.c      |   12 ++++--------
 fs/jbd2/transaction.c |    6 ++----
 3 files changed, 11 insertions(+), 22 deletions(-)

diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 6b8338e..ab26122 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -51,10 +51,8 @@ int __init jbd2_journal_init_transaction_cache(void)
 
 void jbd2_journal_destroy_transaction_cache(void)
 {
-	if (transaction_cache) {
-		kmem_cache_destroy(transaction_cache);
-		transaction_cache = NULL;
-	}
+	kmem_cache_destroy(transaction_cache);
+	transaction_cache = NULL;
 }
 
 void jbd2_journal_free_transaction(transaction_t *transaction)
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 8270fe9..6b8c2c5 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -2240,8 +2240,7 @@ static void jbd2_journal_destroy_slabs(void)
 	int i;
 
 	for (i = 0; i < JBD2_MAX_SLABS; i++) {
-		if (jbd2_slab[i])
-			kmem_cache_destroy(jbd2_slab[i]);
+		kmem_cache_destroy(jbd2_slab[i]);
 		jbd2_slab[i] = NULL;
 	}
 }
@@ -2360,10 +2359,8 @@ static int jbd2_journal_init_journal_head_cache(void)
 
 static void jbd2_journal_destroy_journal_head_cache(void)
 {
-	if (jbd2_journal_head_cache) {
-		kmem_cache_destroy(jbd2_journal_head_cache);
-		jbd2_journal_head_cache = NULL;
-	}
+	kmem_cache_destroy(jbd2_journal_head_cache);
+	jbd2_journal_head_cache = NULL;
 }
 
 /*
@@ -2621,10 +2618,8 @@ static int __init jbd2_journal_init_handle_cache(void)
 
 static void jbd2_journal_destroy_handle_cache(void)
 {
-	if (jbd2_handle_cache)
-		kmem_cache_destroy(jbd2_handle_cache);
-	if (jbd2_inode_cache)
-		kmem_cache_destroy(jbd2_inode_cache);
+	kmem_cache_destroy(jbd2_handle_cache);
+	kmem_cache_destroy(jbd2_inode_cache);
 
 }
 
diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c
index 0abf2e7..1e77a9d 100644
--- a/fs/jbd2/revoke.c
+++ b/fs/jbd2/revoke.c
@@ -183,14 +183,10 @@ static struct jbd2_revoke_record_s *find_revoke_record(journal_t *journal,
 
 void jbd2_journal_destroy_revoke_caches(void)
 {
-	if (jbd2_revoke_record_cache) {
-		kmem_cache_destroy(jbd2_revoke_record_cache);
-		jbd2_revoke_record_cache = NULL;
-	}
-	if (jbd2_revoke_table_cache) {
-		kmem_cache_destroy(jbd2_revoke_table_cache);
-		jbd2_revoke_table_cache = NULL;
-	}
+	kmem_cache_destroy(jbd2_revoke_record_cache);
+	jbd2_revoke_record_cache = NULL;
+	kmem_cache_destroy(jbd2_revoke_table_cache);
+	jbd2_revoke_table_cache = NULL;
 }
 
 int __init jbd2_journal_init_revoke_caches(void)

[PATCH 20/39] ixgbe: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
index 631c603..5f98870 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_fcoe.c
@@ -620,8 +620,7 @@ static void ixgbe_fcoe_dma_pool_free(struct ixgbe_fcoe *fcoe, unsigned int cpu)
 	struct ixgbe_fcoe_ddp_pool *ddp_pool;
 
 	ddp_pool = per_cpu_ptr(fcoe->ddp_pool, cpu);
-	if (ddp_pool->pool)
-		dma_pool_destroy(ddp_pool->pool);
+	dma_pool_destroy(ddp_pool->pool);
 	ddp_pool->pool = NULL;
 }
 

[PATCH 21/39] drbd: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/block/drbd/drbd_main.c |   21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 74d97f4..d98eeec 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2034,20 +2034,13 @@ static void drbd_destroy_mempools(void)
 
 	if (drbd_md_io_bio_set)
 		bioset_free(drbd_md_io_bio_set);
-	if (drbd_md_io_page_pool)
-		mempool_destroy(drbd_md_io_page_pool);
-	if (drbd_ee_mempool)
-		mempool_destroy(drbd_ee_mempool);
-	if (drbd_request_mempool)
-		mempool_destroy(drbd_request_mempool);
-	if (drbd_ee_cache)
-		kmem_cache_destroy(drbd_ee_cache);
-	if (drbd_request_cache)
-		kmem_cache_destroy(drbd_request_cache);
-	if (drbd_bm_ext_cache)
-		kmem_cache_destroy(drbd_bm_ext_cache);
-	if (drbd_al_ext_cache)
-		kmem_cache_destroy(drbd_al_ext_cache);
+	mempool_destroy(drbd_md_io_page_pool);
+	mempool_destroy(drbd_ee_mempool);
+	mempool_destroy(drbd_request_mempool);
+	kmem_cache_destroy(drbd_ee_cache);
+	kmem_cache_destroy(drbd_request_cache);
+	kmem_cache_destroy(drbd_bm_ext_cache);
+	kmem_cache_destroy(drbd_al_ext_cache);
 
 	drbd_md_io_bio_set   = NULL;
 	drbd_md_io_page_pool = NULL;

[PATCH 22/39] nfsd: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/nfsd/nfscache.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index 46ec934..116940c 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -217,10 +217,8 @@ void nfsd_reply_cache_shutdown(void)
 	drc_hashtbl = NULL;
 	drc_hashsize = 0;
 
-	if (drc_slab) {
-		kmem_cache_destroy(drc_slab);
-		drc_slab = NULL;
-	}
+	kmem_cache_destroy(drc_slab);
+	drc_slab = NULL;
 }
 
 /*

Re: [PATCH 22/39] nfsd: drop null test before destroy functions

[J. Bruce Fields]

Thanks, applying.--b.

On Sun, Sep 13, 2015 at 02:15:15PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL) {
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>   x = NULL;
> -}
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  fs/nfsd/nfscache.c |    6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
> index 46ec934..116940c 100644
> --- a/fs/nfsd/nfscache.c
> +++ b/fs/nfsd/nfscache.c
> @@ -217,10 +217,8 @@ void nfsd_reply_cache_shutdown(void)
>  	drc_hashtbl = NULL;
>  	drc_hashsize = 0;
>  
> -	if (drc_slab) {
> -		kmem_cache_destroy(drc_slab);
> -		drc_slab = NULL;
> -	}
> +	kmem_cache_destroy(drc_slab);
> +	drc_slab = NULL;
>  }
>  
>  /*

[PATCH 23/39] UBI: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/mtd/ubi/attach.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/mtd/ubi/attach.c b/drivers/mtd/ubi/attach.c
index 68eea5b..c1aaf03 100644
--- a/drivers/mtd/ubi/attach.c
+++ b/drivers/mtd/ubi/attach.c
@@ -1209,9 +1209,7 @@ static void destroy_ai(struct ubi_attach_info *ai)
 		}
 	}
 
-	if (ai->aeb_slab_cache)
-		kmem_cache_destroy(ai->aeb_slab_cache);
-
+	kmem_cache_destroy(ai->aeb_slab_cache);
 	kfree(ai);
 }
 

Re: [PATCH 23/39] UBI: drop null test before destroy functions

[Richard Weinberger]

Am 13.09.2015 um 14:15 schrieb Julia Lawall:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  drivers/mtd/ubi/attach.c |    4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/mtd/ubi/attach.c b/drivers/mtd/ubi/attach.c
> index 68eea5b..c1aaf03 100644
> --- a/drivers/mtd/ubi/attach.c
> +++ b/drivers/mtd/ubi/attach.c
> @@ -1209,9 +1209,7 @@ static void destroy_ai(struct ubi_attach_info *ai)
>  		}
>  	}
>  
> -	if (ai->aeb_slab_cache)
> -		kmem_cache_destroy(ai->aeb_slab_cache);
> -
> +	kmem_cache_destroy(ai->aeb_slab_cache);
>  	kfree(ai);
>  }

Applied!

Thanks,
//richard

[PATCH 24/39] dlm: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/dlm/memory.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/dlm/memory.c b/fs/dlm/memory.c
index 7cd24bc..0349c89 100644
--- a/fs/dlm/memory.c
+++ b/fs/dlm/memory.c
@@ -38,10 +38,8 @@ int __init dlm_memory_init(void)
 
 void dlm_memory_exit(void)
 {
-	if (lkb_cache)
-		kmem_cache_destroy(lkb_cache);
-	if (rsb_cache)
-		kmem_cache_destroy(rsb_cache);
+	kmem_cache_destroy(lkb_cache);
+	kmem_cache_destroy(rsb_cache);
 }
 
 char *dlm_allocate_lvb(struct dlm_ls *ls)

[PATCH 25/39] net: core: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 net/core/sock.c |   12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/net/core/sock.c b/net/core/sock.c
index ca2984a..3307c02 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2740,10 +2740,8 @@ static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
 		return;
 	kfree(rsk_prot->slab_name);
 	rsk_prot->slab_name = NULL;
-	if (rsk_prot->slab) {
-		kmem_cache_destroy(rsk_prot->slab);
-		rsk_prot->slab = NULL;
-	}
+	kmem_cache_destroy(rsk_prot->slab);
+	rsk_prot->slab = NULL;
 }
 
 static int req_prot_init(const struct proto *prot)
@@ -2828,10 +2826,8 @@ void proto_unregister(struct proto *prot)
 	list_del(&prot->node);
 	mutex_unlock(&proto_list_mutex);
 
-	if (prot->slab != NULL) {
-		kmem_cache_destroy(prot->slab);
-		prot->slab = NULL;
-	}
+	kmem_cache_destroy(prot->slab);
+	prot->slab = NULL;
 
 	req_prot_cleanup(prot->rsk_prot);
 

Re: [PATCH 25/39] net: core: drop null test before destroy functions

[David Miller]

From: Julia Lawall <Julia.Lawall@lip6.fr>
Date: Sun, 13 Sep 2015 14:15:18 +0200

> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL) {
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>   x = NULL;
> -}
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied.

[PATCH 26/39] dmaengine: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/dma/dmaengine.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 3ff284c..45df9a4 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -1066,11 +1066,9 @@ static void dmaengine_destroy_unmap_pool(void)
 	for (i = 0; i < ARRAY_SIZE(unmap_pool); i++) {
 		struct dmaengine_unmap_pool *p = &unmap_pool[i];
 
-		if (p->pool)
-			mempool_destroy(p->pool);
+		mempool_destroy(p->pool);
 		p->pool = NULL;
-		if (p->cache)
-			kmem_cache_destroy(p->cache);
+		kmem_cache_destroy(p->cache);
 		p->cache = NULL;
 	}
 }

Re: [PATCH 26/39] dmaengine: drop null test before destroy functions

[Vinod Koul]

On Sun, Sep 13, 2015 at 02:15:19PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 

Applied, thanks

-- 
~Vinod

[PATCH 27/39] ocfs2: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);

@@
expression x;
@@

-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/ocfs2/dlm/dlmlock.c   |    3 +--
 fs/ocfs2/dlm/dlmmaster.c |   16 +++++-----------
 fs/ocfs2/super.c         |   18 ++++++------------
 fs/ocfs2/uptodate.c      |    3 +--
 4 files changed, 13 insertions(+), 27 deletions(-)

diff --git a/fs/ocfs2/uptodate.c b/fs/ocfs2/uptodate.c
index 82e17b0..78f09c7 100644
--- a/fs/ocfs2/uptodate.c
+++ b/fs/ocfs2/uptodate.c
@@ -633,6 +633,5 @@ int __init init_ocfs2_uptodate_cache(void)
 
 void exit_ocfs2_uptodate_cache(void)
 {
-	if (ocfs2_uptodate_cachep)
-		kmem_cache_destroy(ocfs2_uptodate_cachep);
+	kmem_cache_destroy(ocfs2_uptodate_cachep);
 }
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index 46b8b2b..eb53b98 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -414,8 +414,7 @@ int dlm_init_mle_cache(void)
 
 void dlm_destroy_mle_cache(void)
 {
-	if (dlm_mle_cache)
-		kmem_cache_destroy(dlm_mle_cache);
+	kmem_cache_destroy(dlm_mle_cache);
 }
 
 static void dlm_mle_release(struct kref *kref)
@@ -472,15 +471,10 @@ bail:
 
 void dlm_destroy_master_caches(void)
 {
-	if (dlm_lockname_cache) {
-		kmem_cache_destroy(dlm_lockname_cache);
-		dlm_lockname_cache = NULL;
-	}
-
-	if (dlm_lockres_cache) {
-		kmem_cache_destroy(dlm_lockres_cache);
-		dlm_lockres_cache = NULL;
-	}
+	kmem_cache_destroy(dlm_lockname_cache);
+	dlm_lockname_cache = NULL;
+	kmem_cache_destroy(dlm_lockres_cache);
+	dlm_lockres_cache = NULL;
 }
 
 static void dlm_lockres_release(struct kref *kref)
diff --git a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c
index 66c2a49..7496231 100644
--- a/fs/ocfs2/dlm/dlmlock.c
+++ b/fs/ocfs2/dlm/dlmlock.c
@@ -77,8 +77,7 @@ int dlm_init_lock_cache(void)
 
 void dlm_destroy_lock_cache(void)
 {
-	if (dlm_lock_cache)
-		kmem_cache_destroy(dlm_lock_cache);
+	kmem_cache_destroy(dlm_lock_cache);
 }
 
 /* Tell us whether we can grant a new lock request.
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 2de4c8a..88396d2 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1786,12 +1786,9 @@ static int ocfs2_initialize_mem_caches(void)
 					NULL);
 	if (!ocfs2_inode_cachep || !ocfs2_dquot_cachep ||
 	    !ocfs2_qf_chunk_cachep) {
-		if (ocfs2_inode_cachep)
-			kmem_cache_destroy(ocfs2_inode_cachep);
-		if (ocfs2_dquot_cachep)
-			kmem_cache_destroy(ocfs2_dquot_cachep);
-		if (ocfs2_qf_chunk_cachep)
-			kmem_cache_destroy(ocfs2_qf_chunk_cachep);
+		kmem_cache_destroy(ocfs2_inode_cachep);
+		kmem_cache_destroy(ocfs2_dquot_cachep);
+		kmem_cache_destroy(ocfs2_qf_chunk_cachep);
 		return -ENOMEM;
 	}
 
@@ -1805,16 +1802,13 @@ static void ocfs2_free_mem_caches(void)
 	 * destroy cache.
 	 */
 	rcu_barrier();
-	if (ocfs2_inode_cachep)
-		kmem_cache_destroy(ocfs2_inode_cachep);
+	kmem_cache_destroy(ocfs2_inode_cachep);
 	ocfs2_inode_cachep = NULL;
 
-	if (ocfs2_dquot_cachep)
-		kmem_cache_destroy(ocfs2_dquot_cachep);
+	kmem_cache_destroy(ocfs2_dquot_cachep);
 	ocfs2_dquot_cachep = NULL;
 
-	if (ocfs2_qf_chunk_cachep)
-		kmem_cache_destroy(ocfs2_qf_chunk_cachep);
+	kmem_cache_destroy(ocfs2_qf_chunk_cachep);
 	ocfs2_qf_chunk_cachep = NULL;
 }
 

[PATCH 28/39] ecryptfs: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/ecryptfs/main.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index 4f4d047..e83f31c 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -737,8 +737,7 @@ static void ecryptfs_free_kmem_caches(void)
 		struct ecryptfs_cache_info *info;
 
 		info = &ecryptfs_cache_infos[i];
-		if (*(info->cache))
-			kmem_cache_destroy(*(info->cache));
+		kmem_cache_destroy(*(info->cache));
 	}
 }
 

Re: [PATCH 28/39] ecryptfs: drop null test before destroy functions

[Tyler Hicks]

[-- Attachment #1: Type: text/plain, Size: 1148 bytes --]

On 2015-09-13 14:15:21, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Acked-by: Tyler Hicks <tyhicks@canonical.com>

I assume that you'll be landing this patch set into Linus' tree all
together. Let me know if that's incorrect and I should take this single
patch into the eCryptfs dev tree.

Thanks!

Tyler

> 
> ---
>  fs/ecryptfs/main.c |    3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
> index 4f4d047..e83f31c 100644
> --- a/fs/ecryptfs/main.c
> +++ b/fs/ecryptfs/main.c
> @@ -737,8 +737,7 @@ static void ecryptfs_free_kmem_caches(void)
>  		struct ecryptfs_cache_info *info;
>  
>  		info = &ecryptfs_cache_infos[i];
> -		if (*(info->cache))
> -			kmem_cache_destroy(*(info->cache));
> +		kmem_cache_destroy(*(info->cache));
>  	}
>  }
>  
> 

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Re: [PATCH 28/39] ecryptfs: drop null test before destroy functions

[Julia Lawall]

On Mon, 14 Sep 2015, Tyler Hicks wrote:

> On 2015-09-13 14:15:21, Julia Lawall wrote:
> > Remove unneeded NULL test.
> > 
> > The semantic patch that makes this change is as follows:
> > (http://coccinelle.lip6.fr/)
> > 
> > // <smpl>
> > @@ expression x; @@
> > -if (x != NULL)
> >   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> > // </smpl>
> > 
> > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> Acked-by: Tyler Hicks <tyhicks@canonical.com>
> 
> I assume that you'll be landing this patch set into Linus' tree all
> together. Let me know if that's incorrect and I should take this single
> patch into the eCryptfs dev tree.

I'm not doing anythign after this point.  Some others have taken the patch
into their trees.

julia

> 
> Thanks!
> 
> Tyler
> 
> > 
> > ---
> >  fs/ecryptfs/main.c |    3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> > 
> > diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
> > index 4f4d047..e83f31c 100644
> > --- a/fs/ecryptfs/main.c
> > +++ b/fs/ecryptfs/main.c
> > @@ -737,8 +737,7 @@ static void ecryptfs_free_kmem_caches(void)
> >  		struct ecryptfs_cache_info *info;
> >  
> >  		info = &ecryptfs_cache_infos[i];
> > -		if (*(info->cache))
> > -			kmem_cache_destroy(*(info->cache));
> > +		kmem_cache_destroy(*(info->cache));
> >  	}
> >  }
> >  
> > 
> 

Re: [PATCH 28/39] ecryptfs: drop null test before destroy functions

[Tyler Hicks]

[-- Attachment #1: Type: text/plain, Size: 1810 bytes --]

On 2015-09-15 06:36:30, Julia Lawall wrote:
> 
> 
> On Mon, 14 Sep 2015, Tyler Hicks wrote:
> 
> > On 2015-09-13 14:15:21, Julia Lawall wrote:
> > > Remove unneeded NULL test.
> > > 
> > > The semantic patch that makes this change is as follows:
> > > (http://coccinelle.lip6.fr/)
> > > 
> > > // <smpl>
> > > @@ expression x; @@
> > > -if (x != NULL)
> > >   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> > > // </smpl>
> > > 
> > > Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> > 
> > Acked-by: Tyler Hicks <tyhicks@canonical.com>
> > 
> > I assume that you'll be landing this patch set into Linus' tree all
> > together. Let me know if that's incorrect and I should take this single
> > patch into the eCryptfs dev tree.
> 
> I'm not doing anythign after this point.  Some others have taken the patch
> into their trees.

I've taken it into my tree. Thanks again.

Tyler

> 
> julia
> 
> > 
> > Thanks!
> > 
> > Tyler
> > 
> > > 
> > > ---
> > >  fs/ecryptfs/main.c |    3 +--
> > >  1 file changed, 1 insertion(+), 2 deletions(-)
> > > 
> > > diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
> > > index 4f4d047..e83f31c 100644
> > > --- a/fs/ecryptfs/main.c
> > > +++ b/fs/ecryptfs/main.c
> > > @@ -737,8 +737,7 @@ static void ecryptfs_free_kmem_caches(void)
> > >  		struct ecryptfs_cache_info *info;
> > >  
> > >  		info = &ecryptfs_cache_infos[i];
> > > -		if (*(info->cache))
> > > -			kmem_cache_destroy(*(info->cache));
> > > +		kmem_cache_destroy(*(info->cache));
> > >  	}
> > >  }
> > >  
> > > 
> > 
> --
> To unsubscribe from this list: send the line "unsubscribe ecryptfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

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[PATCH 29/39] thunderbolt: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/thunderbolt/ctl.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c
index 799634b..163b283 100644
--- a/drivers/thunderbolt/ctl.c
+++ b/drivers/thunderbolt/ctl.c
@@ -530,8 +530,7 @@ void tb_ctl_free(struct tb_ctl *ctl)
 		tb_ctl_pkg_free(ctl->rx_packets[i]);
 
 
-	if (ctl->frame_pool)
-		dma_pool_destroy(ctl->frame_pool);
+	dma_pool_destroy(ctl->frame_pool);
 	kfree(ctl);
 }
 

[PATCH 30/39] block: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 block/bio-integrity.c |    7 ++-----
 block/bio.c           |    7 ++-----
 block/blk-core.c      |    3 +--
 block/elevator.c      |    3 +--
 4 files changed, 6 insertions(+), 14 deletions(-)

diff --git a/block/elevator.c b/block/elevator.c
index 84d6394..e3e9021 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -847,8 +847,7 @@ int elv_register(struct elevator_type *e)
 	spin_lock(&elv_list_lock);
 	if (elevator_find(e->elevator_name)) {
 		spin_unlock(&elv_list_lock);
-		if (e->icq_cache)
-			kmem_cache_destroy(e->icq_cache);
+		kmem_cache_destroy(e->icq_cache);
 		return -EBUSY;
 	}
 	list_add_tail(&e->list, &elv_list);
diff --git a/block/bio.c b/block/bio.c
index ad3f276..aee3290 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1850,11 +1850,8 @@ void bioset_free(struct bio_set *bs)
 	if (bs->rescue_workqueue)
 		destroy_workqueue(bs->rescue_workqueue);
 
-	if (bs->bio_pool)
-		mempool_destroy(bs->bio_pool);
-
-	if (bs->bvec_pool)
-		mempool_destroy(bs->bvec_pool);
+	mempool_destroy(bs->bio_pool);
+	mempool_destroy(bs->bvec_pool);
 
 	bioset_integrity_free(bs);
 	bio_put_slab(bs);
diff --git a/block/blk-core.c b/block/blk-core.c
index 2eb722d..7dbebd9 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -619,8 +619,7 @@ int blk_init_rl(struct request_list *rl, struct request_queue *q,
 
 void blk_exit_rl(struct request_list *rl)
 {
-	if (rl->rq_pool)
-		mempool_destroy(rl->rq_pool);
+	mempool_destroy(rl->rq_pool);
 }
 
 struct request_queue *blk_alloc_queue(gfp_t gfp_mask)
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 4aecca7..d3e3046 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -490,11 +490,8 @@ EXPORT_SYMBOL(bioset_integrity_create);
 
 void bioset_integrity_free(struct bio_set *bs)
 {
-	if (bs->bio_integrity_pool)
-		mempool_destroy(bs->bio_integrity_pool);
-
-	if (bs->bvec_integrity_pool)
-		mempool_destroy(bs->bvec_integrity_pool);
+	mempool_destroy(bs->bio_integrity_pool);
+	mempool_destroy(bs->bvec_integrity_pool);
 }
 EXPORT_SYMBOL(bioset_integrity_free);
 

[PATCH 31/39] KVM: MMU: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 arch/x86/kvm/mmu.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 69088a1..fb0c1bd 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -4883,10 +4883,8 @@ static struct shrinker mmu_shrinker = {
 
 static void mmu_destroy_caches(void)
 {
-	if (pte_list_desc_cache)
-		kmem_cache_destroy(pte_list_desc_cache);
-	if (mmu_page_header_cache)
-		kmem_cache_destroy(mmu_page_header_cache);
+	kmem_cache_destroy(pte_list_desc_cache);
+	kmem_cache_destroy(mmu_page_header_cache);
 }
 
 int kvm_mmu_module_init(void)

Re: [PATCH 31/39] KVM: MMU: drop null test before destroy functions

[Paolo Bonzini]

On 13/09/2015 14:15, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  arch/x86/kvm/mmu.c |    6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index 69088a1..fb0c1bd 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -4883,10 +4883,8 @@ static struct shrinker mmu_shrinker = {
>  
>  static void mmu_destroy_caches(void)
>  {
> -	if (pte_list_desc_cache)
> -		kmem_cache_destroy(pte_list_desc_cache);
> -	if (mmu_page_header_cache)
> -		kmem_cache_destroy(mmu_page_header_cache);
> +	kmem_cache_destroy(pte_list_desc_cache);
> +	kmem_cache_destroy(mmu_page_header_cache);
>  }
>  
>  int kvm_mmu_module_init(void)
> 

Acked-by: Paolo Bonzini <pbonzini@redhat.com>

[PATCH 32/39] drm: i915: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/gpu/drm/i915/i915_dma.c |   19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index ab37d11..1dc7c21 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1059,12 +1059,9 @@ out_freecsr:
 put_bridge:
 	pci_dev_put(dev_priv->bridge_dev);
 free_priv:
-	if (dev_priv->requests)
-		kmem_cache_destroy(dev_priv->requests);
-	if (dev_priv->vmas)
-		kmem_cache_destroy(dev_priv->vmas);
-	if (dev_priv->objects)
-		kmem_cache_destroy(dev_priv->objects);
+	kmem_cache_destroy(dev_priv->requests);
+	kmem_cache_destroy(dev_priv->vmas);
+	kmem_cache_destroy(dev_priv->objects);
 	kfree(dev_priv);
 	return ret;
 }
@@ -1150,13 +1147,9 @@ int i915_driver_unload(struct drm_device *dev)
 	if (dev_priv->regs != NULL)
 		pci_iounmap(dev->pdev, dev_priv->regs);
 
-	if (dev_priv->requests)
-		kmem_cache_destroy(dev_priv->requests);
-	if (dev_priv->vmas)
-		kmem_cache_destroy(dev_priv->vmas);
-	if (dev_priv->objects)
-		kmem_cache_destroy(dev_priv->objects);
-
+	kmem_cache_destroy(dev_priv->requests);
+	kmem_cache_destroy(dev_priv->vmas);
+	kmem_cache_destroy(dev_priv->objects);
 	pci_dev_put(dev_priv->bridge_dev);
 	kfree(dev_priv);
 

Re: [Intel-gfx] [PATCH 32/39] drm: i915: drop null test before destroy functions

[Daniel Vetter]

On Sun, Sep 13, 2015 at 02:15:25PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Queued for -next, thanks for the patch.
-Daniel

> 
> ---
>  drivers/gpu/drm/i915/i915_dma.c |   19 ++++++-------------
>  1 file changed, 6 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index ab37d11..1dc7c21 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -1059,12 +1059,9 @@ out_freecsr:
>  put_bridge:
>  	pci_dev_put(dev_priv->bridge_dev);
>  free_priv:
> -	if (dev_priv->requests)
> -		kmem_cache_destroy(dev_priv->requests);
> -	if (dev_priv->vmas)
> -		kmem_cache_destroy(dev_priv->vmas);
> -	if (dev_priv->objects)
> -		kmem_cache_destroy(dev_priv->objects);
> +	kmem_cache_destroy(dev_priv->requests);
> +	kmem_cache_destroy(dev_priv->vmas);
> +	kmem_cache_destroy(dev_priv->objects);
>  	kfree(dev_priv);
>  	return ret;
>  }
> @@ -1150,13 +1147,9 @@ int i915_driver_unload(struct drm_device *dev)
>  	if (dev_priv->regs != NULL)
>  		pci_iounmap(dev->pdev, dev_priv->regs);
>  
> -	if (dev_priv->requests)
> -		kmem_cache_destroy(dev_priv->requests);
> -	if (dev_priv->vmas)
> -		kmem_cache_destroy(dev_priv->vmas);
> -	if (dev_priv->objects)
> -		kmem_cache_destroy(dev_priv->objects);
> -
> +	kmem_cache_destroy(dev_priv->requests);
> +	kmem_cache_destroy(dev_priv->vmas);
> +	kmem_cache_destroy(dev_priv->objects);
>  	pci_dev_put(dev_priv->bridge_dev);
>  	kfree(dev_priv);
>  
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

[PATCH 33/39] rbd: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/block/rbd.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index d93a037..0507246 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -5645,10 +5645,8 @@ static int rbd_slab_init(void)
 	if (rbd_segment_name_cache)
 		return 0;
 out_err:
-	if (rbd_obj_request_cache) {
-		kmem_cache_destroy(rbd_obj_request_cache);
-		rbd_obj_request_cache = NULL;
-	}
+	kmem_cache_destroy(rbd_obj_request_cache);
+	rbd_obj_request_cache = NULL;
 
 	kmem_cache_destroy(rbd_img_request_cache);
 	rbd_img_request_cache = NULL;

Re: [PATCH 33/39] rbd: drop null test before destroy functions

[Ilya Dryomov]

On Sun, Sep 13, 2015 at 3:15 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:
> Remove unneeded NULL test.
>
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@ expression x; @@
> -if (x != NULL) {
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>   x = NULL;
> -}
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
>
> ---
>  drivers/block/rbd.c |    6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
> index d93a037..0507246 100644
> --- a/drivers/block/rbd.c
> +++ b/drivers/block/rbd.c
> @@ -5645,10 +5645,8 @@ static int rbd_slab_init(void)
>         if (rbd_segment_name_cache)
>                 return 0;
>  out_err:
> -       if (rbd_obj_request_cache) {
> -               kmem_cache_destroy(rbd_obj_request_cache);
> -               rbd_obj_request_cache = NULL;
> -       }
> +       kmem_cache_destroy(rbd_obj_request_cache);
> +       rbd_obj_request_cache = NULL;
>
>         kmem_cache_destroy(rbd_img_request_cache);
>         rbd_img_request_cache = NULL;

Applied.

Thanks,

                Ilya

[PATCH 34/39] dccp: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);

@@
expression x;
@@

-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 net/dccp/ackvec.c |   12 ++++--------
 net/dccp/ccid.c   |    3 +--
 2 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/net/dccp/ccid.c b/net/dccp/ccid.c
index 8349897..90f77d0 100644
--- a/net/dccp/ccid.c
+++ b/net/dccp/ccid.c
@@ -95,8 +95,7 @@ static struct kmem_cache *ccid_kmem_cache_create(int obj_size, char *slab_name_f
 
 static void ccid_kmem_cache_destroy(struct kmem_cache *slab)
 {
-	if (slab != NULL)
-		kmem_cache_destroy(slab);
+	kmem_cache_destroy(slab);
 }
 
 static int __init ccid_activate(struct ccid_operations *ccid_ops)
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index bd9e718..3de0d03 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -398,12 +398,8 @@ out_err:
 
 void dccp_ackvec_exit(void)
 {
-	if (dccp_ackvec_slab != NULL) {
-		kmem_cache_destroy(dccp_ackvec_slab);
-		dccp_ackvec_slab = NULL;
-	}
-	if (dccp_ackvec_record_slab != NULL) {
-		kmem_cache_destroy(dccp_ackvec_record_slab);
-		dccp_ackvec_record_slab = NULL;
-	}
+	kmem_cache_destroy(dccp_ackvec_slab);
+	dccp_ackvec_slab = NULL;
+	kmem_cache_destroy(dccp_ackvec_record_slab);
+	dccp_ackvec_record_slab = NULL;
 }

Re: [PATCH 34/39] dccp: drop null test before destroy functions

[David Miller]

From: Julia Lawall <Julia.Lawall@lip6.fr>
Date: Sun, 13 Sep 2015 14:15:27 +0200

> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@
> expression x;
> @@
> 
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> 
> @@
> expression x;
> @@
> 
> -if (x != NULL) {
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>   x = NULL;
> -}
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied.

[PATCH 35/39] GFS2: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/gfs2/main.c |   29 +++++++----------------------
 1 file changed, 7 insertions(+), 22 deletions(-)

diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index 241a399..4d78c3e 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -192,28 +192,13 @@ fail:
 fail_lru:
 	unregister_shrinker(&gfs2_qd_shrinker);
 	gfs2_glock_exit();
-
-	if (gfs2_rsrv_cachep)
-		kmem_cache_destroy(gfs2_rsrv_cachep);
-
-	if (gfs2_quotad_cachep)
-		kmem_cache_destroy(gfs2_quotad_cachep);
-
-	if (gfs2_rgrpd_cachep)
-		kmem_cache_destroy(gfs2_rgrpd_cachep);
-
-	if (gfs2_bufdata_cachep)
-		kmem_cache_destroy(gfs2_bufdata_cachep);
-
-	if (gfs2_inode_cachep)
-		kmem_cache_destroy(gfs2_inode_cachep);
-
-	if (gfs2_glock_aspace_cachep)
-		kmem_cache_destroy(gfs2_glock_aspace_cachep);
-
-	if (gfs2_glock_cachep)
-		kmem_cache_destroy(gfs2_glock_cachep);
-
+	kmem_cache_destroy(gfs2_rsrv_cachep);
+	kmem_cache_destroy(gfs2_quotad_cachep);
+	kmem_cache_destroy(gfs2_rgrpd_cachep);
+	kmem_cache_destroy(gfs2_bufdata_cachep);
+	kmem_cache_destroy(gfs2_inode_cachep);
+	kmem_cache_destroy(gfs2_glock_aspace_cachep);
+	kmem_cache_destroy(gfs2_glock_cachep);
 	gfs2_sys_uninit();
 	return error;
 }

[PATCH 36/39] jffs2: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/jffs2/malloc.c |   27 +++++++++------------------
 1 file changed, 9 insertions(+), 18 deletions(-)

diff --git a/fs/jffs2/malloc.c b/fs/jffs2/malloc.c
index b8fd651..ce11897 100644
--- a/fs/jffs2/malloc.c
+++ b/fs/jffs2/malloc.c
@@ -97,25 +97,16 @@ int __init jffs2_create_slab_caches(void)
 
 void jffs2_destroy_slab_caches(void)
 {
-	if(full_dnode_slab)
-		kmem_cache_destroy(full_dnode_slab);
-	if(raw_dirent_slab)
-		kmem_cache_destroy(raw_dirent_slab);
-	if(raw_inode_slab)
-		kmem_cache_destroy(raw_inode_slab);
-	if(tmp_dnode_info_slab)
-		kmem_cache_destroy(tmp_dnode_info_slab);
-	if(raw_node_ref_slab)
-		kmem_cache_destroy(raw_node_ref_slab);
-	if(node_frag_slab)
-		kmem_cache_destroy(node_frag_slab);
-	if(inode_cache_slab)
-		kmem_cache_destroy(inode_cache_slab);
+	kmem_cache_destroy(full_dnode_slab);
+	kmem_cache_destroy(raw_dirent_slab);
+	kmem_cache_destroy(raw_inode_slab);
+	kmem_cache_destroy(tmp_dnode_info_slab);
+	kmem_cache_destroy(raw_node_ref_slab);
+	kmem_cache_destroy(node_frag_slab);
+	kmem_cache_destroy(inode_cache_slab);
 #ifdef CONFIG_JFFS2_FS_XATTR
-	if (xattr_datum_cache)
-		kmem_cache_destroy(xattr_datum_cache);
-	if (xattr_ref_cache)
-		kmem_cache_destroy(xattr_ref_cache);
+	kmem_cache_destroy(xattr_datum_cache);
+	kmem_cache_destroy(xattr_ref_cache);
 #endif
 }
 

[PATCH 37/39] f2fs crypto: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 fs/f2fs/crypto.c |    9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/crypto.c b/fs/f2fs/crypto.c
index 4a62ef1..3c27f04 100644
--- a/fs/f2fs/crypto.c
+++ b/fs/f2fs/crypto.c
@@ -183,8 +183,7 @@ static void f2fs_crypto_destroy(void)
 	list_for_each_entry_safe(pos, n, &f2fs_free_crypto_ctxs, free_list)
 		kmem_cache_free(f2fs_crypto_ctx_cachep, pos);
 	INIT_LIST_HEAD(&f2fs_free_crypto_ctxs);
-	if (f2fs_bounce_page_pool)
-		mempool_destroy(f2fs_bounce_page_pool);
+	mempool_destroy(f2fs_bounce_page_pool);
 	f2fs_bounce_page_pool = NULL;
 }
 
@@ -240,10 +239,8 @@ void f2fs_exit_crypto(void)
 
 	if (f2fs_read_workqueue)
 		destroy_workqueue(f2fs_read_workqueue);
-	if (f2fs_crypto_ctx_cachep)
-		kmem_cache_destroy(f2fs_crypto_ctx_cachep);
-	if (f2fs_crypt_info_cachep)
-		kmem_cache_destroy(f2fs_crypt_info_cachep);
+	kmem_cache_destroy(f2fs_crypto_ctx_cachep);
+	kmem_cache_destroy(f2fs_crypt_info_cachep);
 }
 
 int __init f2fs_init_crypto(void)

RE: [PATCH 37/39] f2fs crypto: drop null test before destroy functions

[Chao Yu]

> -----Original Message-----
> From: Julia Lawall [mailto:Julia.Lawall@lip6.fr]
> Sent: Sunday, September 13, 2015 8:16 PM
> To: Jaegeuk Kim
> Cc: sergey.senozhatsky@gmail.com; kernel-janitors@vger.kernel.org; Changman Lee; Chao Yu;
> linux-f2fs-devel@lists.sourceforge.net; linux-kernel@vger.kernel.org
> Subject: [PATCH 37/39] f2fs crypto: drop null test before destroy functions
> 
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL)
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Acked-by: Chao Yu <chao2.yu@samsung.com>

[PATCH 38/39] iommu/amd: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/iommu/amd_iommu_init.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 5ef347a..5fb59cc 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1755,11 +1755,8 @@ static void __init free_on_init_error(void)
 	free_pages((unsigned long)irq_lookup_table,
 		   get_order(rlookup_table_size));
 
-	if (amd_iommu_irq_cache) {
-		kmem_cache_destroy(amd_iommu_irq_cache);
-		amd_iommu_irq_cache = NULL;
-
-	}
+	kmem_cache_destroy(amd_iommu_irq_cache);
+	amd_iommu_irq_cache = NULL;
 
 	free_pages((unsigned long)amd_iommu_rlookup_table,
 		   get_order(rlookup_table_size));

Re: [PATCH 38/39] iommu/amd: drop null test before destroy functions

[Joerg Roedel]

On Sun, Sep 13, 2015 at 02:15:31PM +0200, Julia Lawall wrote:
> Remove unneeded NULL test.
> 
> The semantic patch that makes this change is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@ expression x; @@
> -if (x != NULL) {
>   \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
>   x = NULL;
> -}
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> ---
>  drivers/iommu/amd_iommu_init.c |    7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)

Applied, thanks.

[PATCH 39/39] usb: host: drop null test before destroy functions

[Julia Lawall]

Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

-if (x != NULL)
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);

@@
expression x;
@@

-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/usb/host/fotg210-hcd.c  |   12 ++++--------
 drivers/usb/host/fusbh200-hcd.c |   12 ++++--------
 2 files changed, 8 insertions(+), 16 deletions(-)

diff --git a/drivers/usb/host/fotg210-hcd.c b/drivers/usb/host/fotg210-hcd.c
index 000ed80..287d595 100644
--- a/drivers/usb/host/fotg210-hcd.c
+++ b/drivers/usb/host/fotg210-hcd.c
@@ -1976,17 +1976,13 @@ static void fotg210_mem_cleanup(struct fotg210_hcd *fotg210)
 	fotg210->dummy = NULL;
 
 	/* DMA consistent memory and pools */
-	if (fotg210->qtd_pool)
-		dma_pool_destroy(fotg210->qtd_pool);
+	dma_pool_destroy(fotg210->qtd_pool);
 	fotg210->qtd_pool = NULL;
 
-	if (fotg210->qh_pool) {
-		dma_pool_destroy(fotg210->qh_pool);
-		fotg210->qh_pool = NULL;
-	}
+	dma_pool_destroy(fotg210->qh_pool);
+	fotg210->qh_pool = NULL;
 
-	if (fotg210->itd_pool)
-		dma_pool_destroy(fotg210->itd_pool);
+	dma_pool_destroy(fotg210->itd_pool);
 	fotg210->itd_pool = NULL;
 
 	if (fotg210->periodic)
diff --git a/drivers/usb/host/fusbh200-hcd.c b/drivers/usb/host/fusbh200-hcd.c
index 1fd8718..b247d71 100644
--- a/drivers/usb/host/fusbh200-hcd.c
+++ b/drivers/usb/host/fusbh200-hcd.c
@@ -1927,17 +1927,13 @@ static void fusbh200_mem_cleanup (struct fusbh200_hcd *fusbh200)
 	fusbh200->dummy = NULL;
 
 	/* DMA consistent memory and pools */
-	if (fusbh200->qtd_pool)
-		dma_pool_destroy (fusbh200->qtd_pool);
+	dma_pool_destroy(fusbh200->qtd_pool);
 	fusbh200->qtd_pool = NULL;
 
-	if (fusbh200->qh_pool) {
-		dma_pool_destroy (fusbh200->qh_pool);
-		fusbh200->qh_pool = NULL;
-	}
+	dma_pool_destroy(fusbh200->qh_pool);
+	fusbh200->qh_pool = NULL;
 
-	if (fusbh200->itd_pool)
-		dma_pool_destroy (fusbh200->itd_pool);
+	dma_pool_destroy(fusbh200->itd_pool);
 	fusbh200->itd_pool = NULL;
 
 	if (fusbh200->periodic)

Re: [PATCH 00/39] drop null test before destroy functions

[SF Markus Elfring]

> Recent commits to kernel/git/torvalds/linux.git have made the following
> functions able to tolerate NULL arguments:
>
> kmem_cache_destroy (commit 3942d29918522)
> mempool_destroy (commit 4e3ca3e033d1)
> dma_pool_destroy (commit 44d7175da6ea)

How do you think about to extend an other SmPL script?

Related topic:
scripts/coccinelle/free: Delete NULL test before freeing functions
https://systeme.lip6.fr/pipermail/cocci/2015-May/001960.html
https://www.mail-archive.com/cocci@systeme.lip6.fr/msg01855.html


> If these changes are OK, I will address the remainder later.

Would anybody like to reuse my general SmPL approach for similar source
code clean-up?

Regards,
Markus