Re: [PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-05-01 Thread Greg KH
On Fri, May 01, 2020 at 03:06:26PM +, Luis Chamberlain wrote: > On Wed, Apr 29, 2020 at 11:49:37AM +0200, Greg KH wrote: > > On Wed, Apr 29, 2020 at 07:46:26AM +, Luis Chamberlain wrote: > > > diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c > > > index 5c52976bd762..383045f67

Re: [PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-05-01 Thread Luis Chamberlain
On Fri, May 1, 2020 at 9:40 AM Luis Chamberlain wrote: > > On Fri, May 01, 2020 at 08:34:23AM -0700, Christoph Hellwig wrote: > > On Fri, May 01, 2020 at 03:06:26PM +, Luis Chamberlain wrote: > > > > You have access to a block device here, please use dev_warn() instead > > > > here for that, t

Re: [PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-05-01 Thread Luis Chamberlain
On Fri, May 01, 2020 at 08:34:23AM -0700, Christoph Hellwig wrote: > On Fri, May 01, 2020 at 03:06:26PM +, Luis Chamberlain wrote: > > > You have access to a block device here, please use dev_warn() instead > > > here for that, that makes it obvious as to what device a "concurrent > > > blktrac

Re: [PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-05-01 Thread Christoph Hellwig
On Fri, May 01, 2020 at 03:06:26PM +, Luis Chamberlain wrote: > > You have access to a block device here, please use dev_warn() instead > > here for that, that makes it obvious as to what device a "concurrent > > blktrace" was attempted for. > > The block device may be empty, one example is fo

Re: [PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-05-01 Thread Luis Chamberlain
On Wed, Apr 29, 2020 at 11:49:37AM +0200, Greg KH wrote: > On Wed, Apr 29, 2020 at 07:46:26AM +, Luis Chamberlain wrote: > > diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c > > index 5c52976bd762..383045f67cb8 100644 > > --- a/kernel/trace/blktrace.c > > +++ b/kernel/trace/blktra

Re: [PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-04-29 Thread Greg KH
On Wed, Apr 29, 2020 at 07:46:26AM +, Luis Chamberlain wrote: > We use one blktrace per request_queue, that means one per the entire > disk. So we cannot run one blktrace on say /dev/vda and then /dev/vda1, > or just two calls on /dev/vda. > > We check for concurrent setup only at the very en

[PATCH v3 5/6] blktrace: break out of blktrace setup on concurrent calls

2020-04-29 Thread Luis Chamberlain
We use one blktrace per request_queue, that means one per the entire disk. So we cannot run one blktrace on say /dev/vda and then /dev/vda1, or just two calls on /dev/vda. We check for concurrent setup only at the very end of the blktrace setup though. If we try to run two concurrent blktraces o