* Re: blktrace hangs after "--kill" option
2009-01-02 5:59 blktrace hangs after "--kill" option Vinay Sridhar
@ 2009-01-05 9:15 ` Jens Axboe
2009-02-03 6:58 ` Vinay Sridhar
2009-02-03 7:06 ` Jens Axboe
2 siblings, 0 replies; 4+ messages in thread
From: Jens Axboe @ 2009-01-05 9:15 UTC (permalink / raw)
To: linux-btrace
On Fri, Jan 02 2009, Vinay Sridhar wrote:
> Hello,
>
> On executing "blktrace -k" on a running trace, the trace hangs. After
> killing the trace, rerunning it results in "BLKTRACESTOP: invalid
> argument" messages.
>
> This was discussed earlier here:
> http://www.mail-archive.com/linux-btrace@vger.kernel.org/msg00229.html
>
> But I dont see this fix to have been included as I'm still seeing this
> error with the the latest kernel. Could someone please indicate why this
> fix didnt go in? I was able to port the above suggested fix to 2.6.28.
I think I wanted to test it a bit more. I'll toss it in for 2.6.29 and
give it some testing! Thanks for the reminder...
>
>
> diff -Nuarp a/block/blktrace.c b/block/blktrace.c
> --- a/block/blktrace.c 2008-12-24 17:26:37.000000000 -0600
> +++ b/block/blktrace.c 2009-01-02 11:13:11.000000000 -0600
> @@ -181,59 +181,12 @@ EXPORT_SYMBOL_GPL(__blk_add_trace);
>
> static struct dentry *blk_tree_root;
> static DEFINE_MUTEX(blk_tree_mutex);
> -static unsigned int root_users;
> -
> -static inline void blk_remove_root(void)
> -{
> - if (blk_tree_root) {
> - debugfs_remove(blk_tree_root);
> - blk_tree_root = NULL;
> - }
> -}
> -
> -static void blk_remove_tree(struct dentry *dir)
> -{
> - mutex_lock(&blk_tree_mutex);
> - debugfs_remove(dir);
> - if (--root_users = 0)
> - blk_remove_root();
> - mutex_unlock(&blk_tree_mutex);
> -}
> -
> -static struct dentry *blk_create_tree(const char *blk_name)
> -{
> - struct dentry *dir = NULL;
> - int created = 0;
> -
> - mutex_lock(&blk_tree_mutex);
> -
> - if (!blk_tree_root) {
> - blk_tree_root = debugfs_create_dir("block", NULL);
> - if (!blk_tree_root)
> - goto err;
> - created = 1;
> - }
> -
> - dir = debugfs_create_dir(blk_name, blk_tree_root);
> - if (dir)
> - root_users++;
> - else {
> - /* Delete root only if we created it */
> - if (created)
> - blk_remove_root();
> - }
> -
> -err:
> - mutex_unlock(&blk_tree_mutex);
> - return dir;
> -}
>
> static void blk_trace_cleanup(struct blk_trace *bt)
> {
> - relay_close(bt->rchan);
> debugfs_remove(bt->msg_file);
> debugfs_remove(bt->dropped_file);
> - blk_remove_tree(bt->dir);
> + relay_close(bt->rchan);
> free_percpu(bt->sequence);
> free_percpu(bt->msg_data);
> kfree(bt);
> @@ -336,7 +289,18 @@ static int blk_subbuf_start_callback(str
>
> static int blk_remove_buf_file_callback(struct dentry *dentry)
> {
> + struct dentry *parent = dentry->d_parent;
> debugfs_remove(dentry);
> +
> + /*
> + * this will fail for all but the last file, but that is ok. what we
> + * care about is the top level buts->name directory going away, when
> + * the last trace file is gone. Then we don't have to rmdir() that
> + * manually on trace stop, so it nicely solves the issue with
> + * force killing of running traces.
> + */
> +
> + debugfs_remove(parent);
> return 0;
> }
>
> @@ -394,7 +358,15 @@ int do_blk_trace_setup(struct request_qu
> goto err;
>
> ret = -ENOENT;
> - dir = blk_create_tree(buts->name);
> +
> + if (!blk_tree_root) {
> + blk_tree_root = debugfs_create_dir("block", NULL);
> + if (!blk_tree_root)
> + return -ENOMEM;
> + }
> +
> + dir = debugfs_create_dir(buts->name, blk_tree_root);
> +
> if (!dir)
> goto err;
>
> @@ -437,8 +409,6 @@ int do_blk_trace_setup(struct request_qu
>
> return 0;
> err:
> - if (dir)
> - blk_remove_tree(dir);
> if (bt) {
> if (bt->msg_file)
> debugfs_remove(bt->msg_file);
>
>
>
> Vinay Sridhar,
> Linux Technology Center,
> IBM ISTL,
> Bangalore, India
>
>
--
Jens Axboe
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: blktrace hangs after "--kill" option
2009-01-02 5:59 blktrace hangs after "--kill" option Vinay Sridhar
2009-01-05 9:15 ` Jens Axboe
@ 2009-02-03 6:58 ` Vinay Sridhar
2009-02-03 7:06 ` Jens Axboe
2 siblings, 0 replies; 4+ messages in thread
From: Vinay Sridhar @ 2009-02-03 6:58 UTC (permalink / raw)
To: linux-btrace
Jens,
Any plans of including this in any of the 2.6.29 rc's?
Thanks,
Vinay
On Mon, 2009-01-05 at 10:15 +0100, Jens Axboe wrote:
> On Fri, Jan 02 2009, Vinay Sridhar wrote:
> > Hello,
> >
> > On executing "blktrace -k" on a running trace, the trace hangs. After
> > killing the trace, rerunning it results in "BLKTRACESTOP: invalid
> > argument" messages.
> >
> > This was discussed earlier here:
> > http://www.mail-archive.com/linux-btrace@vger.kernel.org/msg00229.html
> >
> > But I dont see this fix to have been included as I'm still seeing this
> > error with the the latest kernel. Could someone please indicate why this
> > fix didnt go in? I was able to port the above suggested fix to 2.6.28.
>
> I think I wanted to test it a bit more. I'll toss it in for 2.6.29 and
> give it some testing! Thanks for the reminder...
>
>
> >
> >
> > diff -Nuarp a/block/blktrace.c b/block/blktrace.c
> > --- a/block/blktrace.c 2008-12-24 17:26:37.000000000 -0600
> > +++ b/block/blktrace.c 2009-01-02 11:13:11.000000000 -0600
> > @@ -181,59 +181,12 @@ EXPORT_SYMBOL_GPL(__blk_add_trace);
> >
> > static struct dentry *blk_tree_root;
> > static DEFINE_MUTEX(blk_tree_mutex);
> > -static unsigned int root_users;
> > -
> > -static inline void blk_remove_root(void)
> > -{
> > - if (blk_tree_root) {
> > - debugfs_remove(blk_tree_root);
> > - blk_tree_root = NULL;
> > - }
> > -}
> > -
> > -static void blk_remove_tree(struct dentry *dir)
> > -{
> > - mutex_lock(&blk_tree_mutex);
> > - debugfs_remove(dir);
> > - if (--root_users = 0)
> > - blk_remove_root();
> > - mutex_unlock(&blk_tree_mutex);
> > -}
> > -
> > -static struct dentry *blk_create_tree(const char *blk_name)
> > -{
> > - struct dentry *dir = NULL;
> > - int created = 0;
> > -
> > - mutex_lock(&blk_tree_mutex);
> > -
> > - if (!blk_tree_root) {
> > - blk_tree_root = debugfs_create_dir("block", NULL);
> > - if (!blk_tree_root)
> > - goto err;
> > - created = 1;
> > - }
> > -
> > - dir = debugfs_create_dir(blk_name, blk_tree_root);
> > - if (dir)
> > - root_users++;
> > - else {
> > - /* Delete root only if we created it */
> > - if (created)
> > - blk_remove_root();
> > - }
> > -
> > -err:
> > - mutex_unlock(&blk_tree_mutex);
> > - return dir;
> > -}
> >
> > static void blk_trace_cleanup(struct blk_trace *bt)
> > {
> > - relay_close(bt->rchan);
> > debugfs_remove(bt->msg_file);
> > debugfs_remove(bt->dropped_file);
> > - blk_remove_tree(bt->dir);
> > + relay_close(bt->rchan);
> > free_percpu(bt->sequence);
> > free_percpu(bt->msg_data);
> > kfree(bt);
> > @@ -336,7 +289,18 @@ static int blk_subbuf_start_callback(str
> >
> > static int blk_remove_buf_file_callback(struct dentry *dentry)
> > {
> > + struct dentry *parent = dentry->d_parent;
> > debugfs_remove(dentry);
> > +
> > + /*
> > + * this will fail for all but the last file, but that is ok. what we
> > + * care about is the top level buts->name directory going away, when
> > + * the last trace file is gone. Then we don't have to rmdir() that
> > + * manually on trace stop, so it nicely solves the issue with
> > + * force killing of running traces.
> > + */
> > +
> > + debugfs_remove(parent);
> > return 0;
> > }
> >
> > @@ -394,7 +358,15 @@ int do_blk_trace_setup(struct request_qu
> > goto err;
> >
> > ret = -ENOENT;
> > - dir = blk_create_tree(buts->name);
> > +
> > + if (!blk_tree_root) {
> > + blk_tree_root = debugfs_create_dir("block", NULL);
> > + if (!blk_tree_root)
> > + return -ENOMEM;
> > + }
> > +
> > + dir = debugfs_create_dir(buts->name, blk_tree_root);
> > +
> > if (!dir)
> > goto err;
> >
> > @@ -437,8 +409,6 @@ int do_blk_trace_setup(struct request_qu
> >
> > return 0;
> > err:
> > - if (dir)
> > - blk_remove_tree(dir);
> > if (bt) {
> > if (bt->msg_file)
> > debugfs_remove(bt->msg_file);
> >
> >
> >
> > Vinay Sridhar,
> > Linux Technology Center,
> > IBM ISTL,
> > Bangalore, India
> >
> >
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: blktrace hangs after "--kill" option
2009-01-02 5:59 blktrace hangs after "--kill" option Vinay Sridhar
2009-01-05 9:15 ` Jens Axboe
2009-02-03 6:58 ` Vinay Sridhar
@ 2009-02-03 7:06 ` Jens Axboe
2 siblings, 0 replies; 4+ messages in thread
From: Jens Axboe @ 2009-02-03 7:06 UTC (permalink / raw)
To: linux-btrace
On Tue, Feb 03 2009, Vinay Sridhar wrote:
> Jens,
>
> Any plans of including this in any of the 2.6.29 rc's?
It's already included in 2.6.29-git, it'll be in the next -rc.
>
> Thanks,
> Vinay
>
> On Mon, 2009-01-05 at 10:15 +0100, Jens Axboe wrote:
> > On Fri, Jan 02 2009, Vinay Sridhar wrote:
> > > Hello,
> > >
> > > On executing "blktrace -k" on a running trace, the trace hangs. After
> > > killing the trace, rerunning it results in "BLKTRACESTOP: invalid
> > > argument" messages.
> > >
> > > This was discussed earlier here:
> > > http://www.mail-archive.com/linux-btrace@vger.kernel.org/msg00229.html
> > >
> > > But I dont see this fix to have been included as I'm still seeing this
> > > error with the the latest kernel. Could someone please indicate why this
> > > fix didnt go in? I was able to port the above suggested fix to 2.6.28.
> >
> > I think I wanted to test it a bit more. I'll toss it in for 2.6.29 and
> > give it some testing! Thanks for the reminder...
> >
> >
> > >
> > >
> > > diff -Nuarp a/block/blktrace.c b/block/blktrace.c
> > > --- a/block/blktrace.c 2008-12-24 17:26:37.000000000 -0600
> > > +++ b/block/blktrace.c 2009-01-02 11:13:11.000000000 -0600
> > > @@ -181,59 +181,12 @@ EXPORT_SYMBOL_GPL(__blk_add_trace);
> > >
> > > static struct dentry *blk_tree_root;
> > > static DEFINE_MUTEX(blk_tree_mutex);
> > > -static unsigned int root_users;
> > > -
> > > -static inline void blk_remove_root(void)
> > > -{
> > > - if (blk_tree_root) {
> > > - debugfs_remove(blk_tree_root);
> > > - blk_tree_root = NULL;
> > > - }
> > > -}
> > > -
> > > -static void blk_remove_tree(struct dentry *dir)
> > > -{
> > > - mutex_lock(&blk_tree_mutex);
> > > - debugfs_remove(dir);
> > > - if (--root_users = 0)
> > > - blk_remove_root();
> > > - mutex_unlock(&blk_tree_mutex);
> > > -}
> > > -
> > > -static struct dentry *blk_create_tree(const char *blk_name)
> > > -{
> > > - struct dentry *dir = NULL;
> > > - int created = 0;
> > > -
> > > - mutex_lock(&blk_tree_mutex);
> > > -
> > > - if (!blk_tree_root) {
> > > - blk_tree_root = debugfs_create_dir("block", NULL);
> > > - if (!blk_tree_root)
> > > - goto err;
> > > - created = 1;
> > > - }
> > > -
> > > - dir = debugfs_create_dir(blk_name, blk_tree_root);
> > > - if (dir)
> > > - root_users++;
> > > - else {
> > > - /* Delete root only if we created it */
> > > - if (created)
> > > - blk_remove_root();
> > > - }
> > > -
> > > -err:
> > > - mutex_unlock(&blk_tree_mutex);
> > > - return dir;
> > > -}
> > >
> > > static void blk_trace_cleanup(struct blk_trace *bt)
> > > {
> > > - relay_close(bt->rchan);
> > > debugfs_remove(bt->msg_file);
> > > debugfs_remove(bt->dropped_file);
> > > - blk_remove_tree(bt->dir);
> > > + relay_close(bt->rchan);
> > > free_percpu(bt->sequence);
> > > free_percpu(bt->msg_data);
> > > kfree(bt);
> > > @@ -336,7 +289,18 @@ static int blk_subbuf_start_callback(str
> > >
> > > static int blk_remove_buf_file_callback(struct dentry *dentry)
> > > {
> > > + struct dentry *parent = dentry->d_parent;
> > > debugfs_remove(dentry);
> > > +
> > > + /*
> > > + * this will fail for all but the last file, but that is ok. what we
> > > + * care about is the top level buts->name directory going away, when
> > > + * the last trace file is gone. Then we don't have to rmdir() that
> > > + * manually on trace stop, so it nicely solves the issue with
> > > + * force killing of running traces.
> > > + */
> > > +
> > > + debugfs_remove(parent);
> > > return 0;
> > > }
> > >
> > > @@ -394,7 +358,15 @@ int do_blk_trace_setup(struct request_qu
> > > goto err;
> > >
> > > ret = -ENOENT;
> > > - dir = blk_create_tree(buts->name);
> > > +
> > > + if (!blk_tree_root) {
> > > + blk_tree_root = debugfs_create_dir("block", NULL);
> > > + if (!blk_tree_root)
> > > + return -ENOMEM;
> > > + }
> > > +
> > > + dir = debugfs_create_dir(buts->name, blk_tree_root);
> > > +
> > > if (!dir)
> > > goto err;
> > >
> > > @@ -437,8 +409,6 @@ int do_blk_trace_setup(struct request_qu
> > >
> > > return 0;
> > > err:
> > > - if (dir)
> > > - blk_remove_tree(dir);
> > > if (bt) {
> > > if (bt->msg_file)
> > > debugfs_remove(bt->msg_file);
> > >
> > >
> > >
> > > Vinay Sridhar,
> > > Linux Technology Center,
> > > IBM ISTL,
> > > Bangalore, India
> > >
> > >
> >
>
--
Jens Axboe
^ permalink raw reply [flat|nested] 4+ messages in thread