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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0A6BFC25B75 for ; Wed, 15 May 2024 09:56:49 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1C68410E53B; Wed, 15 May 2024 09:56:48 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="i3buWgzr"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id 12B1C10E53B for ; Wed, 15 May 2024 09:56:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1715767006; x=1747303006; h=from:to:subject:in-reply-to:references:date:message-id: mime-version; bh=U+L4XsrB0uizqZ9ivxYWgSvRZV6FPutrCTtoT8FDyg4=; b=i3buWgzrmczfCZtusDnlqEVZBOg+OaBC67SwGViYLVKUP3F++1nTSYrK kDQUUfCyh66zJ+g0UBITBIEZt79lt0gu0nAiV5M4YQ1Mg8CB70CXmiU0l zrYedP0zoDDXHIFJCI3pxXcuVdECNIUrzxiGOWdaFlZ3Nj2Kf7XGIgvPU Mp/MojlMNDwt4vtyJHvkh5leSZFtcwevJmqEfna5RM1aToyLMcT6ykWse RSIvvgezi1D35oaHoDiIT3na+JefIa/BFyyqcnlsGuO9/XwGqsWPc6RhX fUE0iaU/mNK8gInYI5kEInJRJeDzYYI/lD7uy3kAtjdxlQvl4VlZ4EUgC g==; X-CSE-ConnectionGUID: p/0C87QsSS+a5qwWkhcHJQ== X-CSE-MsgGUID: CrwagrtmRw6KXXVgKlWFAA== X-IronPort-AV: E=McAfee;i="6600,9927,11073"; a="11749388" X-IronPort-AV: E=Sophos;i="6.08,161,1712646000"; d="scan'208";a="11749388" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 May 2024 02:56:10 -0700 X-CSE-ConnectionGUID: CI7I1U0nQ4CmVxrlcOmOxg== X-CSE-MsgGUID: x8z32otJTZ+ct5a4Nrh8yw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,161,1712646000"; d="scan'208";a="35546362" Received: from mwiniars-desk2.ger.corp.intel.com (HELO localhost) ([10.245.246.141]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 May 2024 02:56:08 -0700 From: Jani Nikula To: Michal Wajdeczko , dri-devel@lists.freedesktop.org Subject: Re: [RFC] drm/print: Introduce drm_line_printer In-Reply-To: <20240514145631.2128-1-michal.wajdeczko@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20240514145631.2128-1-michal.wajdeczko@intel.com> Date: Wed, 15 May 2024 12:56:05 +0300 Message-ID: <87seyjcsay.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, 14 May 2024, Michal Wajdeczko wrote: > This drm printer wrapper can be used to increase the robustness of > the captured output generated by any other drm_printer to make sure > we didn't lost any intermediate lines of the output by adding line > numbers to each output line. Helpful for capturing some crash data. Interesting. Nothing another level of abstraction can't solve. ;) Except maybe it'll make adding function names to debug printers harder. No strong feelings either way about it, I'll let others chime in. A few comments inline. BR, Jani. > > Signed-off-by: Michal Wajdeczko > --- > drivers/gpu/drm/drm_print.c | 9 +++++++++ > include/drm/drm_print.h | 37 +++++++++++++++++++++++++++++++++++++ > 2 files changed, 46 insertions(+) > > diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c > index cf2efb44722c..d6fb50d3407a 100644 > --- a/drivers/gpu/drm/drm_print.c > +++ b/drivers/gpu/drm/drm_print.c > @@ -214,6 +214,15 @@ void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf) > } > EXPORT_SYMBOL(__drm_printfn_err); > > +void __drm_printfn_line(struct drm_printer *p, struct va_format *vaf) > +{ > + unsigned int line = (uintptr_t)(++p->prefix); Subtle. Might warrant adding a union in struct drm_printer for clarity. > + struct drm_printer *dp = p->arg; > + > + drm_printf(dp, "%u: %pV", line, vaf); > +} > +EXPORT_SYMBOL(__drm_printfn_line); > + > /** > * drm_puts - print a const string to a &drm_printer stream > * @p: the &drm printer > diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h > index 089950ad8681..58cc73c53853 100644 > --- a/include/drm/drm_print.h > +++ b/include/drm/drm_print.h > @@ -186,6 +186,7 @@ void __drm_puts_seq_file(struct drm_printer *p, const char *str); > void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf); > void __drm_printfn_dbg(struct drm_printer *p, struct va_format *vaf); > void __drm_printfn_err(struct drm_printer *p, struct va_format *vaf); > +void __drm_printfn_line(struct drm_printer *p, struct va_format *vaf); > > __printf(2, 3) > void drm_printf(struct drm_printer *p, const char *f, ...); > @@ -357,6 +358,42 @@ static inline struct drm_printer drm_err_printer(struct drm_device *drm, > return p; > } > > +/** > + * drm_line_printer - construct a &drm_printer that prefixes outputs with line numbers > + * @dp: the &struct drm_printer which actually generates the output > + * > + * This printer can be used to increase the robustness of the captured output > + * to make sure we didn't lost any intermediate lines of the output. Helpful > + * while capturing some crash data. > + * > + * For example:: > + * > + * void crash_dump(struct drm_device *drm) > + * { > + * struct drm_printer dp = drm_err_printer(drm, "crash"); > + * struct drm_printer lp = drm_line_printer(&dp); > + * > + * drm_printf(&lp, "foo"); > + * drm_printf(&lp, "bar"); > + * } > + * > + * Above code will print into the dmesg something like:: > + * > + * [ ] 0000:00:00.0: [drm] *ERROR* crash 1: foo > + * [ ] 0000:00:00.0: [drm] *ERROR* crash 2: bar > + * > + * RETURNS: > + * The &drm_printer object > + */ > +static inline struct drm_printer drm_line_printer(struct drm_printer *dp) Just p is customary for the drm_printer. "dp" gives me too much Display Port vibes. > +{ > + struct drm_printer lp = { > + .printfn = __drm_printfn_line, > + .arg = dp, > + }; > + return lp; > +} > + > /* > * struct device based logging > * -- Jani Nikula, Intel