Messages in this thread |  | | Date | Wed, 1 Apr 2020 00:29:17 +0200 | From | Thierry Reding <> | Subject | Re: [PATCH] clocksource: Add debugfs support |
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On Wed, Apr 01, 2020 at 12:06:37AM +0200, Thomas Gleixner wrote: > Thierry, > > Thierry Reding <thierry.reding@gmail.com> writes: > > Add a top-level "clocksource" directory to debugfs. For each clocksource > > registered with the system, a subdirectory will be added with attributes > > that can be queried to obtain information about the clocksource. > > first of all this does tell what this patch does but omits the more > important information about the WHY. > > What's even worse is that the changelog is blantantly wrong. > > > +static int clocksource_debugfs_counter_show(struct seq_file *s, void *data) > > +{ > > + struct clocksource *cs = s->private; > > + > > + seq_printf(s, "%llu\n", cs->read(cs)); > > + > > + return 0; > > +} > > +DEFINE_SHOW_ATTRIBUTE(clocksource_debugfs_counter); > > + > > +static void clocksource_debugfs_add(struct clocksource *cs) > > +{ > > + if (!debugfs_root) > > + return; > > + > > + cs->debugfs = debugfs_create_dir(cs->name, debugfs_root); > > + > > + debugfs_create_file("counter", 0444, cs->debugfs, cs, > > + &clocksource_debugfs_counter_fops); > > +} > > It does not provide any information about the clocksource, it provides > an interface to read the counter - nothing else.
The counter is part of the information about a clocksource, isn't it? But yes, frankly I had anticipated that I'd be adding more files here and when I ended up not doing that I forgot to update the patch description.
I can also add some information about what I intend to use this for, though it'll be a bit boring because I really only want this as a way of testing that I'm reading from the right registers and that these counters are running. A debugfs interface seemed like a better and more widely useful way to achieve that than implementing some one-off hack to poll those registers.
Thierry [unhandled content-type:application/pgp-signature] |  |