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=-13.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 41290C4361A for ; Sat, 5 Dec 2020 18:57:47 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 792D72310B for ; Sat, 5 Dec 2020 18:57:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 792D72310B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 155696E444; Sat, 5 Dec 2020 18:57:45 +0000 (UTC) Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by gabe.freedesktop.org (Postfix) with ESMTPS id C5FF86E444 for ; Sat, 5 Dec 2020 18:57:43 +0000 (UTC) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id D7CDBD2F; Sat, 5 Dec 2020 19:57:40 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1607194661; bh=iS269bbfYLp92PTNIyeM9gLH85gTe/Q/HC24LDmd6p8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LsDg6B2l1FkpVuX9YYxCU72f5ZrgkPRFiYHpg7IxeTimK8DMLLkY9NI2cM8whfG7p +XGuWGB/ubNLoypDjIrvD5oiBHSitw/Bks9QJwexGw4Gsnuv0+9ONzOb/e+I/OqrjD OPqly2/bqlexPyTaDB/fIf8S8RVwJpsE4sqLKW3g= Date: Sat, 5 Dec 2020 20:57:38 +0200 From: Laurent Pinchart To: Philipp Zabel Subject: Re: [PATCH v3 1/7] drm: add drmm_encoder_alloc() Message-ID: References: <20200911135724.25833-1-p.zabel@pengutronix.de> <20201204091732.GD4109@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: 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: , Cc: kernel@pengutronix.de, dri-devel@lists.freedesktop.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Philipp, On Fri, Dec 04, 2020 at 11:12:20AM +0100, Philipp Zabel wrote: > On Fri, 2020-12-04 at 11:17 +0200, Laurent Pinchart wrote: > > On Fri, Sep 11, 2020 at 03:57:18PM +0200, Philipp Zabel wrote: > > > Add an alternative to drm_encoder_init() that allocates and initializes > > > an encoder and registers drm_encoder_cleanup() with > > > drmm_add_action_or_reset(). > > > > > > Signed-off-by: Philipp Zabel > > > --- > > > Changes since v2: > > > - call va_start() / va_end() unconditionally > > > --- > > > drivers/gpu/drm/drm_encoder.c | 101 ++++++++++++++++++++++++++-------- > > > include/drm/drm_encoder.h | 30 ++++++++++ > > > 2 files changed, 108 insertions(+), 23 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/drm_encoder.c b/drivers/gpu/drm/drm_encoder.c > > > index e555281f43d4..f5414705f9ad 100644 > > > --- a/drivers/gpu/drm/drm_encoder.c > > > +++ b/drivers/gpu/drm/drm_encoder.c > > > @@ -26,6 +26,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > > > > #include "drm_crtc_internal.h" > > > > > > @@ -91,25 +92,11 @@ void drm_encoder_unregister_all(struct drm_device *dev) > > > } > > > } > > > > > > -/** > > > - * drm_encoder_init - Init a preallocated encoder > > > - * @dev: drm device > > > - * @encoder: the encoder to init > > > - * @funcs: callbacks for this encoder > > > - * @encoder_type: user visible type of the encoder > > > - * @name: printf style format string for the encoder name, or NULL for default name > > > - * > > > - * Initialises a preallocated encoder. Encoder should be subclassed as part of > > > - * driver encoder objects. At driver unload time drm_encoder_cleanup() should be > > > - * called from the driver's &drm_encoder_funcs.destroy hook. > > > - * > > > - * Returns: > > > - * Zero on success, error code on failure. > > > - */ > > > -int drm_encoder_init(struct drm_device *dev, > > > - struct drm_encoder *encoder, > > > - const struct drm_encoder_funcs *funcs, > > > - int encoder_type, const char *name, ...) > > > +__printf(5, 0) > > > +static int __drm_encoder_init(struct drm_device *dev, > > > + struct drm_encoder *encoder, > > > + const struct drm_encoder_funcs *funcs, > > > + int encoder_type, const char *name, va_list ap) > > > { > > > int ret; > > > > > > @@ -125,11 +112,7 @@ int drm_encoder_init(struct drm_device *dev, > > > encoder->encoder_type = encoder_type; > > > encoder->funcs = funcs; > > > if (name) { > > > - va_list ap; > > > - > > > - va_start(ap, name); > > > encoder->name = kvasprintf(GFP_KERNEL, name, ap); > > > - va_end(ap); > > > } else { > > > encoder->name = kasprintf(GFP_KERNEL, "%s-%d", > > > drm_encoder_enum_list[encoder_type].name, > > > @@ -150,6 +133,36 @@ int drm_encoder_init(struct drm_device *dev, > > > > > > return ret; > > > } > > > + > > > +/** > > > + * drm_encoder_init - Init a preallocated encoder > > > + * @dev: drm device > > > + * @encoder: the encoder to init > > > + * @funcs: callbacks for this encoder > > > + * @encoder_type: user visible type of the encoder > > > + * @name: printf style format string for the encoder name, or NULL for default name > > > + * > > > + * Initializes a preallocated encoder. Encoder should be subclassed as part of > > > + * driver encoder objects. At driver unload time drm_encoder_cleanup() should be > > > + * called from the driver's &drm_encoder_funcs.destroy hook. > > > + * > > > + * Returns: > > > + * Zero on success, error code on failure. > > > + */ > > > +int drm_encoder_init(struct drm_device *dev, > > > + struct drm_encoder *encoder, > > > + const struct drm_encoder_funcs *funcs, > > > + int encoder_type, const char *name, ...) > > > +{ > > > + va_list ap; > > > + int ret; > > > + > > > + va_start(ap, name); > > > + ret = __drm_encoder_init(dev, encoder, funcs, encoder_type, name, ap); > > > + va_end(ap); > > > + > > > + return ret; > > > +} > > > EXPORT_SYMBOL(drm_encoder_init); > > > > > > /** > > > @@ -181,6 +194,48 @@ void drm_encoder_cleanup(struct drm_encoder *encoder) > > > } > > > EXPORT_SYMBOL(drm_encoder_cleanup); > > > > > > +static void drmm_encoder_alloc_release(struct drm_device *dev, void *ptr) > > > +{ > > > + struct drm_encoder *encoder = ptr; > > > + > > > + if (WARN_ON(!encoder->dev)) > > > + return; > > > + > > > + drm_encoder_cleanup(encoder); > > > +} > > > + > > > +void *__drmm_encoder_alloc(struct drm_device *dev, size_t size, size_t offset, > > > + const struct drm_encoder_funcs *funcs, > > > + int encoder_type, const char *name, ...) > > > +{ > > > + void *container; > > > + struct drm_encoder *encoder; > > > + va_list ap; > > > + int ret; > > > + > > > + if (WARN_ON(!funcs || funcs->destroy)) > > > + return ERR_PTR(-EINVAL); > > > + > > > + container = drmm_kzalloc(dev, size, GFP_KERNEL); > > > + if (!container) > > > + return ERR_PTR(-EINVAL); > > > + > > > + encoder = container + offset; > > > + > > > + va_start(ap, name); > > > + ret = __drm_encoder_init(dev, encoder, funcs, encoder_type, name, ap); > > > + va_end(ap); > > > + if (ret) > > > + return ERR_PTR(ret); > > > + > > > + ret = drmm_add_action_or_reset(dev, drmm_encoder_alloc_release, encoder); > > > + if (ret) > > > + return ERR_PTR(ret); > > > > Given that drmm_encoder_alloc_release() will be called right before the > > kfree related to the above drmm_kzalloc(), wouldn't it be more efficient > > to replace drmm_kzalloc() with kzalloc() and add a kfree() in > > drmm_encoder_alloc_release() ? That will save one context allocation. > > That is not quite as trivial: drmm_encoder_alloc_release() doesn't know > the container pointer that must be passed to kfree(), nor the offset > between container and encoder. Indeed :-S Adding more context to the drmres when creating it with drmm_add_action_or_reset() would solve this, but it's probably overkill (although I think this would definitely be useful if/when we turn the DRM resource manager to a more generic component usable by other subsystems). > > With this addressed, > > > > Reviewed-by: Laurent Pinchart You can add my tag to this patch and the other ones in the series where I've made the same comment. -- Regards, Laurent Pinchart _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel