From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maciej Matraszek Subject: Re: [PATCH] PM / Domains: add debugfs listing of struct generic_pm_domain-s Date: Wed, 10 Sep 2014 17:38:13 +0200 Message-ID: <1410363493.15593.26.camel@AMDC723> References: <1410348536-15201-1-git-send-email-m.matraszek@samsung.com> <20140910144340.GA17967@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <20140910144340.GA17967@kroah.com> Sender: linux-kernel-owner@vger.kernel.org To: Greg Kroah-Hartman Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Len Brown , Pavel Machek , Krzysztof Kozlowski , Bartlomiej Zolnierkiewicz List-Id: linux-pm@vger.kernel.org Hi Greg, thanks for your reply! > > +static int __init pm_genpd_debug_init(void) > > +{ > > + struct dentry *d; > > + > > + pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL); > > + > > + /* No debugfs */ > > + if (IS_ERR(pm_genpd_debugfs_dir)) > > + return PTR_ERR(pm_genpd_debugfs_dir); > > You shouldn't care at all, just do this check: > > > + if (!pm_genpd_debugfs_dir) > > + return -ENOMEM; > > And all will be fine, because: > > > + d = debugfs_create_file("pm_genpd_summary", S_IRUGO, > > + pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops); > > That call will resolve away to nothing if debugfs is not enabled, and it > doesn't make much sense to do anything with an "error" of no debugfs. Great! I'll fix this bizarre double check. > > > + if (!d) > > + return -ENOMEM; > > + > > + return 0; > > +} > > +late_initcall(pm_genpd_debug_init); > > +#endif /* CONFIG_PM_ADVANCED_DEBUG */ > > No tear-down of the debugfs files on shutdown? In drivers/clk/clk.c, there is no tear-down of debugfs files paired with clk_debug_init(), same with wakeup_sources_debugfs_init() from drivers/base/power/wakeup.c. On the other hand, some subsystems perform it. What would you prefer? > > thanks, > > greg k-h Thanks, -- Maciej Matraszek Samsung R&D Institute Poland Samsung Electronics