From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 854B2196C73 for ; Wed, 5 Jun 2024 12:11:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717589508; cv=none; b=W0Rl/EWDCnvQGl2UVxQ4AFOmhsDcbrH69VmXaNHvWzDwIgYMXn80bAOxMZJ4ewa/SpzAzociaE3/aIi/lijHTEseMgLTy+yWtjt3IvSwWQ0mHzGYvH9zOfJsRSTLqTvLExPZsSGzhpMBSMawKD2eoKDHlA66OXNRWHxhuCoPbss= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717589508; c=relaxed/simple; bh=cwTJba3C8Qwz1ZLeDncLpCLV7/mbQe8fxcLPmmDJQto=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=FoZNejn4E9LTOH0EEn7zzUsbXgz3Xu9vglTVOL2ixzZd3JVT8UYQfdL80H4zaDKj6xM7DzyEz3K4QEO1szv3uHmhZ12ROxq8kbcDs8EXFv5Q/H9YMlis3RevjulnmNRy/MiaYPwQc4H4Bvps1xQsqoNMeS43sG3fb6lclr4BJOg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AWKkrD6k; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AWKkrD6k" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6728EC32781; Wed, 5 Jun 2024 12:11:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717589508; bh=cwTJba3C8Qwz1ZLeDncLpCLV7/mbQe8fxcLPmmDJQto=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AWKkrD6kulejFb9Jcnx/Dpfk8fUAEF1BuapcvVUBFriLJ64IFO7T9o///SetkdC5j hRKoiH9NdxNg3aWmre+8+wZmMSGTuK5HXW1KCxtIptk3CEUWU17SjrLLVGUUrCy+Kx UZfx1egKTnttA1GOKyR/uhJIde6qZdSM/Hp5o3joj2v2s+Ldp2VCMSo4LZmb6cNCWI zf9hyiyq5gbMOJqPVWCA7Pg1gvRniuj6o4xgez74OtfbEXTIfDvJQCM/Lan5dNpZ0y MGxKcrKXmXXES50RTevVcy9X0okES53ldURt4qnI+BM8ZUpxlVGQSvyBll9rZr74Ea XvpEKlfHy9zCg== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1sEpUc-0000000079R-06fM; Wed, 05 Jun 2024 14:11:50 +0200 Date: Wed, 5 Jun 2024 14:11:50 +0200 From: Johan Hovold To: Pierre-Louis Bossart Cc: Johan Hovold , Vinod Koul , Bard Liao , Sanyog Kale , alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 3/4] soundwire: bus: clean up probe warnings Message-ID: References: <20240604075213.20815-1-johan+linaro@kernel.org> <20240604075213.20815-4-johan+linaro@kernel.org> <8dd7cadc-138c-4ef5-b06f-7177550b1215@linux.intel.com> <970501b1-09ae-4f2c-a078-2b4f23fe460e@linux.intel.com> <0d15954f-0158-4a56-afef-f0d043135146@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0d15954f-0158-4a56-afef-f0d043135146@linux.intel.com> On Tue, Jun 04, 2024 at 05:07:39PM +0200, Pierre-Louis Bossart wrote: > \ > >>>>> @@ -123,7 +123,7 @@ static int sdw_drv_probe(struct device *dev) > >>>>> /* init the dynamic sysfs attributes we need */ > >>>>> ret = sdw_slave_sysfs_dpn_init(slave); > >>>>> if (ret < 0) > >>>>> - dev_warn(dev, "Slave sysfs init failed:%d\n", ret); > >>>>> + dev_warn(dev, "failed to initialise sysfs: %d\n", ret); > >>>>> > >>>>> /* > >>>>> * Check for valid clk_stop_timeout, use DisCo worst case value of > >>>>> @@ -147,7 +147,7 @@ static int sdw_drv_probe(struct device *dev) > >>>>> if (drv->ops && drv->ops->update_status) { > >>>>> ret = drv->ops->update_status(slave, slave->status); > >>>>> if (ret < 0) > >>>>> - dev_warn(dev, "%s: update_status failed with status %d\n", __func__, ret); > >>>>> + dev_warn(dev, "failed to update status: %d\n", ret); > >>>> > >>>> the __func__ does help IMHO, 'failed to update status' is way too general... > >>> > >>> Error messages printed with dev_warn will include the device and driver > >>> names so this message will be quite specific still. > >> > >> The goal isn't to be 'quite specific' but rather 'completely > >> straightforward'. Everyone can lookup a function name in a xref tool and > >> quickly find out what happened. Doing 'git grep' on message logs isn't > >> great really, and over time logs tend to be copy-pasted. Just look at > >> the number of patches where we had to revisit the dev_err logs to make > >> then really unique/useful. > > > > Error message should be self-contained and give user's some idea of what > > went wrong and not leak implementation details like function names (and > > be greppable, which "%s:" is not). > > "Failed to update status" doesn't sound terribly self-contained to me. > > It's actually a great example of making the logs less clear with good > intentions. How many people know that the SoundWire bus exposes an > 'update_status' callback, and that callback can be invoked from two > completely different places (probe or on device attachment)? > > /* Ensure driver knows that peripheral unattached */ > ret = sdw_update_slave_status(slave, status[i]); > if (ret < 0) > dev_warn(&slave->dev, "Update Slave status failed:%d\n", ret); > > You absolutely want to know which of these two cases failed, but with > your changes they now look rather identical except for the order of > words. one would be 'failed to update status' and the other 'update > status failed'. > > What is much better is to know WHEN this failure happens, then folks > looking at logs to fix a problem don't need to worry about precise > wording or word order. > > It's a constant battle to get meaningful messages that are useful for > validation/integration folks, and my take is that it's a > windmill-fighting endeavor. The function name is actually more useful, > it's not an implementation detail, it's what you're looking for when > reverse-engineering problematic sequences from a series of CI logs. Just add "at probe" to differentiate the two cases if you really think this is an issue: dev_warn(dev, "failed to update status at probe: %d\n", ret); Johan