Tim Gardner
2013-Feb-13 20:30 UTC
[Ocfs2-devel] [PATCH linux-next v2] ocfs2: remove kfree() redundant null checks
smatch analysis indicates a number of redundant NULL checks before
calling kfree(), e.g.,
fs/ocfs2/alloc.c:6138 ocfs2_begin_truncate_log_recovery() info:
redundant null check on *tl_copy calling kfree()
fs/ocfs2/alloc.c:6755 ocfs2_zero_range_for_truncate() info:
redundant null check on pages calling kfree()
etc....
Cc: Mark Fasheh <mfasheh at suse.com>
Cc: Joel Becker <jlbec at evilplan.org>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita at gmail.com>
Cc: Al Viro <viro at zeniv.linux.org.uk>
Cc: "David S. Miller" <davem at davemloft.net>
Cc: Tejun Heo <tj at kernel.org>
Cc: Jiri Kosina <jkosina at suse.cz>
Cc: ocfs2-devel at oss.oracle.com
Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
---
v2 - Decided to fix all the kfree() smatch warnings in one patch. Also
fixed an erroneous change to fs/ocfs2/alloc.c in v1.
fs/ocfs2/alloc.c | 5 ++---
fs/ocfs2/cluster/heartbeat.c | 6 ++----
fs/ocfs2/cluster/tcp.c | 6 ++----
fs/ocfs2/dlm/dlmdomain.c | 4 +---
fs/ocfs2/extent_map.c | 3 +--
fs/ocfs2/journal.c | 10 +++-------
fs/ocfs2/localalloc.c | 8 +++-----
fs/ocfs2/stack_o2cb.c | 2 +-
fs/ocfs2/super.c | 6 ++----
fs/ocfs2/sysfile.c | 3 +--
10 files changed, 18 insertions(+), 35 deletions(-)
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
index 31b9463..83a1a1d 100644
--- a/fs/ocfs2/alloc.c
+++ b/fs/ocfs2/alloc.c
@@ -6134,7 +6134,7 @@ bail:
iput(tl_inode);
brelse(tl_bh);
- if (status < 0 && (*tl_copy)) {
+ if (status < 0) {
kfree(*tl_copy);
*tl_copy = NULL;
mlog_errno(status);
@@ -6751,8 +6751,7 @@ int ocfs2_zero_range_for_truncate(struct inode *inode,
handle_t *handle,
mlog_errno(ret);
out:
- if (pages)
- kfree(pages);
+ kfree(pages);
return ret;
}
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index ff753bb..8c3318b 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -1449,8 +1449,7 @@ static void o2hb_region_release(struct config_item *item)
mlog(ML_HEARTBEAT, "hb region release (%s)\n", reg->hr_dev_name);
- if (reg->hr_tmp_block)
- kfree(reg->hr_tmp_block);
+ kfree(reg->hr_tmp_block);
if (reg->hr_slot_data) {
for (i = 0; i < reg->hr_num_pages; i++) {
@@ -1464,8 +1463,7 @@ static void o2hb_region_release(struct config_item *item)
if (reg->hr_bdev)
blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
- if (reg->hr_slots)
- kfree(reg->hr_slots);
+ kfree(reg->hr_slots);
kfree(reg->hr_db_regnum);
kfree(reg->hr_db_livenodes);
diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index 33b8924..aa88bd8 100644
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c
@@ -1159,10 +1159,8 @@ out:
o2net_debug_del_nst(&nst); /* must be before dropping sc and node */
if (sc)
sc_put(sc);
- if (vec)
- kfree(vec);
- if (msg)
- kfree(msg);
+ kfree(vec);
+ kfree(msg);
o2net_complete_nsw(nn, &nsw, 0, 0, 0);
return ret;
}
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 9e89d70..dbb17c0 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -319,9 +319,7 @@ static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
if (dlm->master_hash)
dlm_free_pagevec((void **)dlm->master_hash, DLM_HASH_PAGES);
- if (dlm->name)
- kfree(dlm->name);
-
+ kfree(dlm->name);
kfree(dlm);
}
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index f487aa3..1c39efb 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -282,8 +282,7 @@ search:
spin_unlock(&oi->ip_lock);
out:
- if (new_emi)
- kfree(new_emi);
+ kfree(new_emi);
}
static int ocfs2_last_eb_is_empty(struct inode *inode,
diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 2dd36af..8eccfab 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -1234,11 +1234,8 @@ static void ocfs2_queue_recovery_completion(struct
ocfs2_journal *journal,
/* Though we wish to avoid it, we are in fact safe in
* skipping local alloc cleanup as fsck.ocfs2 is more
* than capable of reclaiming unused space. */
- if (la_dinode)
- kfree(la_dinode);
-
- if (tl_dinode)
- kfree(tl_dinode);
+ kfree(la_dinode);
+ kfree(tl_dinode);
if (qrec)
ocfs2_free_quota_recovery(qrec);
@@ -1408,8 +1405,7 @@ bail:
mutex_unlock(&osb->recovery_lock);
- if (rm_quota)
- kfree(rm_quota);
+ kfree(rm_quota);
/* no one is callint kthread_stop() for us so the kthread() api
* requires that we call do_exit(). And it isn't exported, but
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
index a9f78c7..aebeacd 100644
--- a/fs/ocfs2/localalloc.c
+++ b/fs/ocfs2/localalloc.c
@@ -476,8 +476,7 @@ out:
if (local_alloc_inode)
iput(local_alloc_inode);
- if (alloc_copy)
- kfree(alloc_copy);
+ kfree(alloc_copy);
}
/*
@@ -534,7 +533,7 @@ int ocfs2_begin_local_alloc_recovery(struct ocfs2_super
*osb,
mlog_errno(status);
bail:
- if ((status < 0) && (*alloc_copy)) {
+ if (status < 0) {
kfree(*alloc_copy);
*alloc_copy = NULL;
}
@@ -1290,8 +1289,7 @@ bail:
if (main_bm_inode)
iput(main_bm_inode);
- if (alloc_copy)
- kfree(alloc_copy);
+ kfree(alloc_copy);
if (ac)
ocfs2_free_alloc_context(ac);
diff --git a/fs/ocfs2/stack_o2cb.c b/fs/ocfs2/stack_o2cb.c
index 9436801..bf1f893 100644
--- a/fs/ocfs2/stack_o2cb.c
+++ b/fs/ocfs2/stack_o2cb.c
@@ -376,7 +376,7 @@ static int o2cb_cluster_connect(struct
ocfs2_cluster_connection *conn)
dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
out_free:
- if (rc && conn->cc_private)
+ if (rc)
kfree(conn->cc_private);
out:
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 0e91ec2..9b6910d 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -2525,8 +2525,7 @@ static int ocfs2_check_volume(struct ocfs2_super *osb)
mlog_errno(status);
finally:
- if (local_alloc)
- kfree(local_alloc);
+ kfree(local_alloc);
if (status)
mlog_errno(status);
@@ -2553,8 +2552,7 @@ static void ocfs2_delete_osb(struct ocfs2_super *osb)
* we free it here.
*/
kfree(osb->journal);
- if (osb->local_alloc_copy)
- kfree(osb->local_alloc_copy);
+ kfree(osb->local_alloc_copy);
kfree(osb->uuid_str);
ocfs2_put_dlm_debug(osb->osb_dlm_debug);
memset(osb, 0, sizeof(struct ocfs2_super));
diff --git a/fs/ocfs2/sysfile.c b/fs/ocfs2/sysfile.c
index 3d635f4..f053688 100644
--- a/fs/ocfs2/sysfile.c
+++ b/fs/ocfs2/sysfile.c
@@ -91,8 +91,7 @@ static struct inode **get_local_system_inode(struct
ocfs2_super *osb,
} else
osb->local_system_inodes = local_system_inodes;
spin_unlock(&osb->osb_lock);
- if (unlikely(free))
- kfree(free);
+ kfree(free);
}
index = (slot * NUM_LOCAL_SYSTEM_INODES) +
--
1.7.9.5
Andrew Morton
2013-Feb-13 23:53 UTC
[Ocfs2-devel] [PATCH linux-next v2] ocfs2: remove kfree() redundant null checks
On Wed, 13 Feb 2013 13:29:45 -0700 Tim Gardner <tim.gardner at canonical.com> wrote:> smatch analysis indicates a number of redundant NULL checks before > calling kfree(), e.g., > > fs/ocfs2/alloc.c:6138 ocfs2_begin_truncate_log_recovery() info: > redundant null check on *tl_copy calling kfree() > > fs/ocfs2/alloc.c:6755 ocfs2_zero_range_for_truncate() info: > redundant null check on pages calling kfree() > > ... > > diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c > index 31b9463..83a1a1d 100644 > --- a/fs/ocfs2/alloc.c > +++ b/fs/ocfs2/alloc.c > @@ -6134,7 +6134,7 @@ bail: > iput(tl_inode); > brelse(tl_bh); > > - if (status < 0 && (*tl_copy)) { > + if (status < 0) { > kfree(*tl_copy); > *tl_copy = NULL; > mlog_errno(status);This change does other things. For example, if ocfs2_begin_truncate_log_recovery()'s first "goto bail" is taken, we will now call mlog_errno(status) twice. That function is pretty confused about its error recovery and logging. it needs some maintenance. I'll omit this hunk of your patch.> @@ -534,7 +533,7 @@ int ocfs2_begin_local_alloc_recovery(struct ocfs2_super *osb, > mlog_errno(status); > > bail: > - if ((status < 0) && (*alloc_copy)) { > + if (status < 0) { > kfree(*alloc_copy); > *alloc_copy = NULL; > }Similar, but this change lokos OK.