| Message ID | 1374919965-11690-1-git-send-email-a3at.mail@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, Jul 27, 2013 at 2:12 PM, Azat Khuzhin <a3at.mail@gmail.com> wrote: > Replace list_for_each_entry() by list_for_each_entry_safe() in > __btrfs_close_devices() > > There is another place that delete items lock_stripe_add(), but there we > don't need safe version, because after deleting we exit from loop. > > Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com> > --- > fs/btrfs/volumes.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > index 78b8717..1d1b595 100644 > --- a/fs/btrfs/volumes.c > +++ b/fs/btrfs/volumes.c > @@ -616,13 +616,13 @@ static void free_device(struct rcu_head *head) > > static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) > { > - struct btrfs_device *device; > + struct btrfs_device *device, *next; > > if (--fs_devices->opened > 0) > return 0; > > mutex_lock(&fs_devices->device_list_mutex); > - list_for_each_entry(device, &fs_devices->devices, dev_list) { > + list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { > struct btrfs_device *new_device; > struct rcu_string *name; There is "kfree(device);" at the end of loop, maybe there must "goto again;" after it? (instead of this patch) > > -- > 1.7.10.4 >
On mon, 29 Jul 2013 11:48:32 +0400, Azat Khuzhin wrote: > On Sat, Jul 27, 2013 at 2:12 PM, Azat Khuzhin <a3at.mail@gmail.com> wrote: >> Replace list_for_each_entry() by list_for_each_entry_safe() in >> __btrfs_close_devices() >> >> There is another place that delete items lock_stripe_add(), but there we >> don't need safe version, because after deleting we exit from loop. >> >> Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com> >> --- >> fs/btrfs/volumes.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c >> index 78b8717..1d1b595 100644 >> --- a/fs/btrfs/volumes.c >> +++ b/fs/btrfs/volumes.c >> @@ -616,13 +616,13 @@ static void free_device(struct rcu_head *head) >> >> static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) >> { >> - struct btrfs_device *device; >> + struct btrfs_device *device, *next; >> >> if (--fs_devices->opened > 0) >> return 0; >> >> mutex_lock(&fs_devices->device_list_mutex); >> - list_for_each_entry(device, &fs_devices->devices, dev_list) { >> + list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { >> struct btrfs_device *new_device; >> struct rcu_string *name; > > There is "kfree(device);" at the end of loop, maybe there must "goto > again;" after it? > (instead of this patch) Your fix is right, we needn't search from the head once again. The other fix way is: call_rcu(&device->rcu, free_device); + device = new_device; } but from the viewpoint of the readability, this way is not so good. Reviewed-by: Miao Xie <miaox@cn.fujitsu.com> > >> >> -- >> 1.7.10.4 >> > > > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Jul 30, 2013 at 7:40 AM, Miao Xie <miaox@cn.fujitsu.com> wrote: > On mon, 29 Jul 2013 11:48:32 +0400, Azat Khuzhin wrote: >> On Sat, Jul 27, 2013 at 2:12 PM, Azat Khuzhin <a3at.mail@gmail.com> wrote: >>> Replace list_for_each_entry() by list_for_each_entry_safe() in >>> __btrfs_close_devices() >>> >>> There is another place that delete items lock_stripe_add(), but there we >>> don't need safe version, because after deleting we exit from loop. >>> >>> Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com> >>> --- >>> fs/btrfs/volumes.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c >>> index 78b8717..1d1b595 100644 >>> --- a/fs/btrfs/volumes.c >>> +++ b/fs/btrfs/volumes.c >>> @@ -616,13 +616,13 @@ static void free_device(struct rcu_head *head) >>> >>> static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) >>> { >>> - struct btrfs_device *device; >>> + struct btrfs_device *device, *next; >>> >>> if (--fs_devices->opened > 0) >>> return 0; >>> >>> mutex_lock(&fs_devices->device_list_mutex); >>> - list_for_each_entry(device, &fs_devices->devices, dev_list) { >>> + list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { >>> struct btrfs_device *new_device; >>> struct rcu_string *name; >> >> There is "kfree(device);" at the end of loop, maybe there must "goto >> again;" after it? >> (instead of this patch) Ugh. I was looking into another function! > > Your fix is right, we needn't search from the head once again. > > The other fix way is: > call_rcu(&device->rcu, free_device); > + device = new_device; > } > but from the viewpoint of the readability, this way is not so good. > > Reviewed-by: Miao Xie <miaox@cn.fujitsu.com> Thanks! Miao, should I resend patch with you reviewed-by? > >> >>> >>> -- >>> 1.7.10.4 >>> >> >> >> >
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 78b8717..1d1b595 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -616,13 +616,13 @@ static void free_device(struct rcu_head *head) static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) { - struct btrfs_device *device; + struct btrfs_device *device, *next; if (--fs_devices->opened > 0) return 0; mutex_lock(&fs_devices->device_list_mutex); - list_for_each_entry(device, &fs_devices->devices, dev_list) { + list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { struct btrfs_device *new_device; struct rcu_string *name;
Replace list_for_each_entry() by list_for_each_entry_safe() in __btrfs_close_devices() There is another place that delete items lock_stripe_add(), but there we don't need safe version, because after deleting we exit from loop. Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com> --- fs/btrfs/volumes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)