From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CAB91C433EF for ; Tue, 14 Sep 2021 07:01:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A7618604AC for ; Tue, 14 Sep 2021 07:01:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240421AbhINHDM (ORCPT ); Tue, 14 Sep 2021 03:03:12 -0400 Received: from mail-ua1-f41.google.com ([209.85.222.41]:36600 "EHLO mail-ua1-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240395AbhINHDE (ORCPT ); Tue, 14 Sep 2021 03:03:04 -0400 Received: by mail-ua1-f41.google.com with SMTP id u11so7979779uaw.3 for ; Tue, 14 Sep 2021 00:01:45 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tuysa/nqFrNnprxpuMVAoQ6N3N8odNTAhlZsCOvCuL8=; b=2Puh/FAyVywUeHNmmiCblUJNAa8kA5R2Et7vitToEChgbdUEQDIAKK+s//muhoWkkR 0Y10NwsOcbRaoKMC6TAWx/0V3f0UF3t9SKkyB/aSEyMNd2Tw96+TPHKRBgdPc4raSwQq t+HKOVd86+OisVyZ9yKxKS6GXiPyCtNsMjkX3LQajkRVAgMdFEHOLLdXWYky26xIJDtO G8Q2EZ6L1Gwka5V/mRxmPLholK4H+lBaK6nEHlAZLxH45mQJtZJ0/MmqtThbzyzS+ZUi TtJpBP76P8WUdJwzdwmYpDapDnoFDYnY23RJHgd3w/FXm7Xx6HunPBtgGMaYdjQzFfjD LiNQ== X-Gm-Message-State: AOAM533q8aUw3zrTUwJVbnX3TAqpxKxtMhsTA63tDf8Lv2f+izAbfrPW ji1n7A9bLWl1px3nDFYdSHTRnuhBm+5qH8O4dW0= X-Google-Smtp-Source: ABdhPJwv/7mKMEA/JE1yUMPoECGTyuAhyjzdKrZ0LmOopoEU1RtDvEhAABml2Yytaq6hUSdqfW2G9DkOEy6wvrUnYDU= X-Received: by 2002:ab0:4d5b:: with SMTP id k27mr2999788uag.78.1631602904013; Tue, 14 Sep 2021 00:01:44 -0700 (PDT) MIME-Version: 1.0 References: <20210914043928.4066136-1-saravanak@google.com> <20210914043928.4066136-3-saravanak@google.com> In-Reply-To: <20210914043928.4066136-3-saravanak@google.com> From: Geert Uytterhoeven Date: Tue, 14 Sep 2021 09:01:32 +0200 Message-ID: Subject: Re: [PATCH v1 2/5] driver core: Set deferred probe reason when deferred by driver core To: Saravana Kannan Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , John Stultz , Marek Szyprowski , Rob Herring , Andrew Lunn , Vladimir Oltean , Android Kernel Team , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Saravana, On Tue, Sep 14, 2021 at 6:39 AM Saravana Kannan wrote: > When the driver core defers the probe of a device, set the deferred > probe reason so that it's easier to debug. The deferred probe reason is > available in debugfs under devices_deferred. > > Signed-off-by: Saravana Kannan Thanks for your patch! > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -955,6 +955,29 @@ static void device_links_missing_supplier(struct device *dev) > } > } > > +/** > + * dev_set_def_probe_reason - Set the deferred probe reason for a device > + * @dev: the pointer to the struct device > + * @fmt: printf-style format string > + * @...: arguments as specified in the format string > + * > + * This is a more caller-friendly version of device_set_deferred_probe_reason() > + * that takes variable argument inputs similar to dev_info(). > + */ > +static void dev_set_def_probe_reason(const struct device *dev, const char *fmt, ...) So this is indeed similar to device_set_deferred_probe_reason(), but the function's name is completely different, unlike e.g. (v)printf()? > +{ > + struct va_format vaf; > + va_list args; > + > + va_start(args, fmt); > + vaf.fmt = fmt; > + vaf.va = &args; > + > + device_set_deferred_probe_reason(dev, &vaf); > + > + va_end(args); > +} I think you can just make this a macro wrapper calling dev_err_probe(dev, -EPROBE_DEFER, fmt, ...). Or open-code that below. > + > /** > * device_links_check_suppliers - Check presence of supplier drivers. > * @dev: Consumer device. > @@ -975,6 +998,7 @@ int device_links_check_suppliers(struct device *dev) > { > struct device_link *link; > int ret = 0; > + struct fwnode_handle *sup_fw; > > /* > * Device waiting for supplier to become available is not allowed to > @@ -983,10 +1007,13 @@ int device_links_check_suppliers(struct device *dev) > mutex_lock(&fwnode_link_lock); > if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) && > !fw_devlink_is_permissive()) { > + sup_fw = list_first_entry(&dev->fwnode->suppliers, > + struct fwnode_link, > + c_hook)->supplier; > dev_dbg(dev, "probe deferral - wait for supplier %pfwP\n", > - list_first_entry(&dev->fwnode->suppliers, > - struct fwnode_link, > - c_hook)->supplier); > + sup_fw); > + dev_set_def_probe_reason(dev, > + "wait for supplier %pfwP\n", sup_fw); dev_err_probe() would replace both the dev_dbg() and the dev_set_def_probe_reason(). > mutex_unlock(&fwnode_link_lock); > return -EPROBE_DEFER; > } > @@ -1003,6 +1030,9 @@ int device_links_check_suppliers(struct device *dev) > device_links_missing_supplier(dev); > dev_dbg(dev, "probe deferral - supplier %s not ready\n", > dev_name(link->supplier)); > + dev_set_def_probe_reason(dev, > + "supplier %s not ready\n", > + dev_name(link->supplier)); Likewise. > ret = -EPROBE_DEFER; > break; > } Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds