On Thu, Feb 02, 2017 at 11:58:53AM +0100, Greg Kroah-Hartman wrote: > On Wed, Feb 01, 2017 at 12:31:15AM -0800, Omar Sandoval wrote: > > On Wed, Feb 01, 2017 at 09:16:08AM +0100, Greg Kroah-Hartman wrote: > > > On Tue, Jan 31, 2017 at 02:53:16PM -0800, Omar Sandoval wrote: > > > > From: Omar Sandoval <osandov@xxxxxx> > > > > > > > > When I moved the blk-mq debugging information to debugfs, I didn't > > > > realize that blktrace also created directories in debugfs that > > > > conflicted with the blk-mq directories. This series fixes that. > > > > > > > > Patch 1 adds a new debugfs helper needed for patch 6. Greg, could I get > > > > an ack on that if it makes sense? Jens and I went back and forth on this > > > > for a little while, but patch 6 has more of the rationale on why we > > > > decided that this approach was the cleanest. > > > > > > I can't find patch 6, you only cc:ed me on the first patch :( > > > > > > Care to bounce them all to me? > > > > > > thanks, > > > > > > greg k-h > > > > Gah, I forgot --cc-cover to git-send-email. The series is all here: > > http://marc.info/?l=linux-block&r=1&b=201701&w=2. I can also send the > > patches directly to you if you prefer that. > > I don't understand the problem here. How do you not know if you have > created the debugfs file or not? You have the structure, with the > correct name, how could it have been created? Can't you save the dentry > to the debugfs file in the structure that has the name? > > thanks, > > greg k-h Hey, Greg, So here's the alternative to doing the lookup: diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 38052f625a0f..79ef6b9d1f96 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -470,12 +470,15 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, if (!blk_debugfs_root) goto err; - dir = debugfs_create_dir(buts->name, blk_debugfs_root); - +#ifdef CONFIG_BLK_DEBUG_FS + if (q->mq_ops && !bdev->bd_part.partno) + dir = q->debugfs_dir; +#endif + if (!dir) + bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root); if (!dir) goto err; - bt->dir = dir; bt->dev = dev; atomic_set(&bt->dropped, 0); INIT_LIST_HEAD(&bt->running_list); So we could figure out if it exists, but it's very special-cased and fragile. And then there's this further up: /* * some device names have larger paths - convert the slashes * to underscores for this to work as expected */ strreplace(buts->name, '/', '_'); which I'm not sure applies anymore but would also break this. Doing the lookup is just more foolproof. Thanks, Omar -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
